[1993] FCA 404; (1993) 44 FCR 239

Patents - Compact low-pressure mercury vapour discharge lamp - infringement of patent - construction of "contains a luminescent material" in patent specification - validity of patent - sufficiency of description - fair basing - invention or manner of manufacture - want of novelty - utility - effect of Patents Act 1990 on patents granted under Patents Act 1952 - revocation of patents granted under 1952 Act using provision of 1990 Act.

Patents Act 1990

D Ryan

Solicitors for the Appellants : Sly and Weigall

Counsel for the Respondent : D K Catterns QC

Dr A C Bennett

Solicitors for the Respondent : Williams Niblett

1. The order for costs made by Wilcox J be varied by ordering the

appellants to pay two-thirds of the costs of the respondent of the

principal proceeding and the cross-claim;

2. Otherwise, the appeal be dismissed;

3. The appellants pay two-thirds of the cost of the respondent of

the appeal.

Note: Settlement and entry of orders is dealt with in Order 36 of the Federal Court Rules.

NORTHROP J I agree with the orders proposed by Lockhart J and concur with his Honour's reasons for making those orders.

LOCKHART J This appeal from the judgment of a judge of the Court (Wilcox J) concerns a patent for a "low-pressure mercury vapour discharge lamp". The patent enables the manufacture of a compact fluorescent lamp which saves energy and has a long life. It represents the development from fluorescent lamps with tubes of various lengths with which we are familiar. The patent was granted to the first appellant under the Patents Act 1952 ("the 1952 Act") on 27 January 1983 for a term of 16 years commencing on 21 August 1978. The priority date is 23 August 1977. The first appellant is a Netherlands corporation and the second appellant is an Australian subsidiary of it. The appellants manufacture and distribute lamps, including compact lamps, known as Philips' lamps.

2. The respondent distributes in Australia compact lamps which are known as Mirabella PLC-E type lamps ("Mirabella lamps"). These lamps, apparently imported from China, are similar in appearance to Philips' compact lamps. The appellants claimed that the Mirabella lamps infringed the first appellant's patent. They sought a declaration to that effect together with an injunction restraining the respondent from making, causing to be made, importing, selling, offering for sale, or distributing Mirabella lamps in Australia. They also sought an order for the delivery up or destruction of all Mirabella lamps in the possession or control of the respondent, together with damages or an account of profits. The respondent disputed these claims and denied infringement. By its cross-claim it challenged the validity of the patent in suit and sought its revocation. Five grounds were mentioned in the cross-claim of the respondent: failure to comply with the requirements of s. 40 of the Patents Act 1990 ("the 1990 Act"), want of novelty, that the subject of the patent is not an invention or manner of manufacture, obviousness and lack of utility. Obviousness was abandoned at the commencement of the trial, but the other grounds have been maintained throughout the proceeding.

3. The learned primary Judge found that there was no infringement by the respondent of the patent in suit and that it was invalid. His Honour ordered that the application be dismissed and that the patent be revoked. He found that the specification did not comply with s. 40 of the 1990 Act and that the invention claimed in the patent was not an invention or a manner of new manufacture; but he found in favour of the appellants on certain of the issues raised by the respondent's cross-claim. He held that the patent sufficiently or fully described the invention; that claims 1 to 5 were fairly based on the matter described in the specification; and that the invention disclosed in the patent was useful and novel. On appeal to this Full Court the parties challenged all findings of his Honour adverse to them.

The compact low-pressure mercury vapour discharge lamp

4. It is necessary to describe a compact low-pressure mercury vapour discharge lamp of the kind with which this case is concerned.

5. A fluorescent lamp is a gas discharge tube, the inner surface of which is coated with a luminescent material comprising a given mixture of fluorescent salts, also known as phosphors. The tube is filled with an inert gas, normally argon, with a small amount of mercury. A gas which is suitable for use in fluorescent lamps is mercury vapour. Discharge lamps using mercury vapour can be of the high pressure type, where the lamp is operated with the mercury vapour at a pressure in the region of 25 kPa or one quarter of atmospheric pressure, or even at far higher pressure. Fluorescent lamps of the kind with which the patent in suit is concerned are of the low pressure type in which the mercury vapour pressure during operation of the lamp is of the order of O.8 kPa, which is eight one-millionth parts of atmospheric pressure. The gas used in the lamp is enclosed within a sealed glass envelope and at each end of the envelope there is an electrical conductor called an electrode which looks rather like the filament of an incandescent lamp. Each electrode has an electrical connection through the wall of the envelope for the supply of electric current to the lamp. During operation of the lamp with alternating current the electrodes are alternately supplying electric current to the lamp and drawing current from it. The electrode which is supplying current is called the anode and the other electrode is called the cathode.

6. When an electric voltage is applied between the electrodes in the tube an electric discharge is struck, initially in the inert gas. The heating of the tube which results from the discharge vaporises the mercury. Energy is then transfered from the free electrons of the gas discharge to the atoms of mercury vapour. Free electrons excite high energy levels of the mercury atoms which, on relaxing, emit radiation at a number of discrete wavelengths. This radiation consists for the most part of invisible ultraviolet rays. The ultraviolet radiation is absorbed by the phosphor which in turn emits radiation with longer wavelengths in the visible region of the spectrum, and, depending on the given mixture of phosphors, different "colours". Speaking generally, it is desirable to have a white light rather than one that is bluish or pinkish in hue. The use of a blend of phosphors has been common industry practice since about 1972. Often a phosphor component is chosen to emit primarily in one colour. By combining phosphors which emit in the red, green and blue portions of the spectrum, a combined emission which appears as white light is obtained. Fluorescent lamps in relatively tubular forms have been known for many years as efficient sources of light; they are more efficient than normal incandescent lamps.

7. The first fluorescent lamps to become widely used in domestic and commercial applications were developed in Europe and the United States during the period 1945-50. These lamps used luminescent materials which provided light emission over a broad region of the visible spectrum. The fluorescent tube used throughout the world during the 1960's had a tubular glass envelope of 38 mm diameter which has as its luminescent material a calcium halophosphate crystalline powder, using various activators such as manganese and antimony, chosen to give a broad spectrum radiation of the required colour temperature. During that period 38 mm was considered to be the diameter which gave optimum efficiency from the gas discharge.

8. About 1970, Westinghouse in the USA and the first appellant in the Netherlands independently arrived at a new approach to the choice of luminescent materials. Instead of employing a single luminescent material capable of emitting light over a broad portion of the visible spectrum, it was found to be more efficient to employ three materials, each of which was an efficient emitter of light in a narrow wavelength band. By choosing the three materials so that their respective emission bands (that is to say, the colours of their emitted light) complemented each other, the eye mixed these three colours to see white light. By using three narrow band phosphors no energy was wasted through radiation at wavelengths to which the eye is relatively insensitive, and the colour of the lamp could be finely tuned by the adjustment of the relative quantities of the three luminescent materials used. This became known as the "three band principle".

9. During the early 1970's luminescent materials, based on crystal lattices of aluminium oxide, and using as activators the rare elements europium, cerium and terbium, emerged from work conducted by the first appellant in the Netherlands as the most suitable green and blue emitting phosphors for use in a commercial lamp employing the three band principle. The most suitable red emitting phosphor appeared to be yttrium oxide. Lamps employing these phosphors were introduced in Europe in 1974. Although these three band luminescent materials were expensive, they enabled greater lamp efficacy to be achieved, with good colour rendering.

10. Luminescent materials or phosphors are materials which have the property of emitting visible light when irradiated with ultraviolet radiation. The ability of a material to do this depends on the energy levels of the material in its solid state. High energy photons of ultraviolet light are absorbed by the phosphor, which then emits less energetic photons of visible light. (A photon of light is analogous to an atom of matter). The early known phosphors involved compounds of barium, magnesium and calcium. There are many hundreds of phosphors, including some natural minerals and biological compounds. New phosphors are constantly being discovered or synthesised; but at any one time less than one hundred phosphors are commercially manufactured on a large scale.

11. Phosphors for use in fluorescent lamps must be efficient, maintain their properties in the atmosphere of the mercury discharge and have their emission in desirable regions of the visible spectrum, so that the total light emitted is "white", rather than looking bluish or pinkish. A range of phosphors having these basic properties was well known for many years prior to 1977. Other considerations such as cost and ease of manufacture further limit the choice of phosphors.

12. A phosphor mixture is selected to meet the particular required criteria, for example, to produce spectral components of emitted light which together look white or withstand radiation at wavelengths of 185 nanometres (which has been known since at least 1963 to degrade some phosphors). (A nanometre is one millionth of a millimetre or 10-9 metres and is commonly abbreviated as "nm"). Since about 1974, for example, it was known that phosphors containing terbium (green/red) and europium (red) could be used to increase the red component of the emitted light to obtain a "warmer" light.

13. Appropriate phosphors and mixtures of phosphors have been selected largely by experimentation. Whether or not a particular phosphor or phosphor mixture has the desired characteristics is determined by standard laboratory techniques.

14. One of the most important characteristics of a phosphor is its efficiency in converting the ultraviolet radiation into visible light in given circumstances. The overall efficiency of a light source is expressed in terms of lumens per watt. (A lumen is the measure of radiant power evaluated according to the ability of the light source to produce the visual sensation of light.) Efficiency will be reduced if power is lost in heat or because of degradation of the phosphor. Most phosphors will have high efficiency, but degrade quickly; whereas others will be less efficient, but have a longer life. The light provided by a lamp is measured by luminous flux in lumens. If the phosphor of a fluorescent lamp is efficient with a high number of lumens per watt then the luminous flux will be high.

15. Compact fluorescent lamps are characterized by small size, energy efficiency and long life. As a consequence of their small size, the luminescent coating of these lamps covers a relatively small area, and therefore receives a high density of radiation from the discharge. The energy loading on the luminescent layer is measured by the "wall loading", which is the power (in watts) dissipated in the mercury vapour discharge column per square metre of luminescent material surface. Expressed another way, the term "wall-loading" is used to describe the ratio between the electrical power input to the lamp and the area of the inside surface of the lamp. Compact lamps, because of their smaller size, have a higher wall-loading than conventional lamps that use the same wattage. A lamp with a high wall-loading is often called a "high-loaded" lamp.

16. The problem addressed by the invention of the patent in suit is the inefficiency of known lamps having high wall loadings. The invention resides in the choice of luminescent materials employed in lamps having a wall loading of at least 400 W/m2. (There is some conflict in the evidence as to whether the minimum is 400 or 500 W/m2, but nothing turns on this.)

17. The most obvious differences between a compact lamp and a conventional fluorescent lamp are size and shape. Whereas the conventional lamp is long and thin (typically a metre or more in length and 3-4 cm in diameter), the compact lamp is small and comparatively squat. Sometimes it is straight, sometimes curved, like an incandescent light globe. But, regardless of shape and size, the principle behind a compact lamp is the same as that behind a conventional fluorescent lamp. The essence of its operation is its ability to convert electrical energy into light by the production of radiation lying within that part of the radiation spectrum which is visible to the human eye.

18. Using the same phosphors, a compact lamp is less efficient than a conventional fluorescent lamp. This is a result of the lamp's smaller size. There are two aspects to this: there is an increase in the proportion of energy which is expended at the electrodes to sustain the discharge and, thus, is lost as heat; and there is a greater proportion of ion recombination at the wall of the tube. The smaller the diameter of the tube, the more readily will ions diffuse to the walls and recombine. Their recombination energy is largely expended as heat, rather than used to produce visible light.

19. The radiation from a low-pressure mercury vapour discharge lamp occurs primarily at two wavelengths: 185 nanometres ("nm") and 254 nm. Radiation at 185 nm has a degrading effect on phosphors, leading to a loss of luminous flux. This loss is often called "short term decrease" or "STD", the name stemming from the fact that the loss occurs within the first few minutes after the lamp is switched on. STD is not cumulative. It persists whilst the lamp is illuminated and recurs, to about the same extent and from about the same base, when the lamp is next switched on. The effect of STD is to reduce the lamp's operating efficiency. Some phosphors are more resistant to STD than others; hence it is important to select phosphors whose characteristics include high STD resistance.

20. Radiation at 254 nm does not degrade phosphors. Indeed, it seems to have a beneficial effect by repairing colour centre damage resulting from the 185 nm radiation. Accordingly, it is desirable to design the lamp in such a manner as to minimise 185 nm radiation and maximise 254 nm radiation. A problem with compact lamps compared with conventional fluorescent lamps, is that their smaller size leads to an increase in the 185 nm/254 nm ratio, thus increasing the problem of phosphor degradation.

21. The phenomenon of electro-negativity ("e.n") was described by Professor Linus Pauling (who in 1945 compiled a list of the e.n of all known elements) as "the power of an atom in a molecule to attract electrons to itself". The combination of cations (the positively charged mercury ions) suitable for a compact lamp must have a relatively low electro-negativity in order to resist degradation of the phosphor by the mercury atoms.

22. Other expressions which require definition to understand the issues in the case shall be dealt with briefly. Atomic number is the number of protons in the nucleus of an atom. The number is unique for any given element.

23. The periodic table is a table of elements arranged in order of increasing atomic number. The various properties recur periodically throughout the sequence of elements. Elements with similar arrangements of electrons are placed under each other in vertical columns called groups. Elements within a group therefore have similar properties. There are eight main groups designated as I to VII, and 0. Group I, for example, includes hydrogen and the alkaline metals such as lithium and sodium. Group VII contains the halides; and group 0 contains the inert gases. A horizontal sequence of the periodic table is called a "period". They are numbered from the top down from 1 to 7.

24. Rare earth elements are elements in a group of elements consisting of lustrous silvery-white metals. They occur naturally as oxides (earths) and are widely distributed throughout the earth's crust. The rare earths consist of 17 elements in the periodic table, 15 with atomic numbers ranging from lanthanum with an atomic number of 57, to lutetium with an atomic number of 71, and including cerium (atomic number 58), europium (atomic number 63) and terbium (atomic number 65) (together known as "the lanthanide series"), and scandium (atomic number 21) and yttrium (atomic number 39).

25. Scandium, yttrium and the lanthanide series belong to the sub-group III(a) of the periodic table. The lanthanides all occupy the same position in the sixth period below yttrium which in turn is below scandium.

26. All the rare earth elements have a similar chemical structure and similar properties. They are all transition elements. The patent specification

27. The specification of the patent in suit commences as follows:

"The invention relates to a low-pressure mercury

vapour discharge lamp having a vacuum-tight

radiation-permeable envelope provided with a

luminescent layer, a gas filling comprising

mercury and a rare gas, and means for

maintaining a column discharge in the gas

filling, the power consumed by the column being

at least 500 W per m2 surface area of the

luminescent layer."

28. The specification then outlines the principles underlying low-pressure mercury vapour discharge lamps, their physical descriptions and manner of operation. Reference is made to conventional fluorescent lamps, the statement being made that the 40 watt T-12 lamp (a lamp 1.2 metres in length and 37 mm in diameter) generally has a wall-loading of about 300 watts per square metre ("W/m2").

29. The specification then says that low-pressure mercury vapour discharge lamps have already been made, wherein a higher wall-loading, of 500 W/m2, is applied. This is said to have been done "with the object of obtaining small and compact lamps". Reference is made to German and United States patents disclosing small lamps with wall-loadings of 2,500 W/m2 and 25,000 W/m2 respectively.

"A great drawback of the prior art lamps with a

relatively high wall load is that the efficiency

of the lamp, that is to say the radiant flux or

luminous flux of the useful radiation emitted by

the luminescent layer ... appears to have a low

value. In particular this efficiency is

considerably lower than that of the normal lamp

(for example the 40 W/T12-lamp). This drawback

is especially felt with the compact lamps and is

one of the reasons that this lamp type, which

might offer great advantages for practical

applications, for example as a substitute for

normal incandescent lamps, has as yet not been

introduced. The reason why it appeared to be

impossible to produce lamps having a high power

input per unit volume and with an efficiency

comparable to that of the normal lamps was not

understood. Also known insights as regards the

optimum mercury vapour pressure ... and means

for controlling the mercury vapour pressure

(amalgams etc) did not lead to the desired

result. It has, therefore, been considered that

producing a compact lamp, for example by

reducing the diameter whilst maintaining the

electric power supplied must inevitably be

accompanied by loss in efficiency."

31. Continuing, the specification deals with the object of the invention in these terms:

"... to provide low-pressure mercury vapour

discharge lamps which in operation has (sic) a

high density of the consumed power and a high

radiation efficiency, so that on the one hand

compact lamps with an efficiency substantially

equal to that of the normal low-pressure mercury

vapour discharge lamps and, on the other hand,

lamps having high current densities with an

improved radiation efficiency become available."

32. The substance of claim 1, with one variation to which I will refer later, is then set out (the consistory clause). It is followed by this description of the course of investigations:

"During the investigations which led to the

invention, it was found that an efficient

conversion of the electric power into ultra-violet

radiation is possible in a highly loaded

lamp. It was surprisingly found that the

efficiency of this conversion can be

substantially equal to that of the normal

40W/T12 lamp. It was found to be a prerequisite

that the electron temperature in the highly

loaded lamp assumes a value which is not lower,

and is, preferably higher than that in the

normal lamp. Various measures are possible to

achieve this. Starting, for example, from the

normal lamp, the required high electron

temperature is maintained if the discharge tube

has a smaller diameter, while the electric power

supplied to the lamp is kept substantially

constant. Compared to the normal lamps, the

electric field strength is then higher, the lamp

current is lower and the wall load is higher

than in the normal lamps. Experiments showed

that said high efficiency of the conversion into

ultra-violet radiation can also be obtained with

very low diameters of the discharge tube (from

one to a few mm). Another measure which makes

it possible to maintain a high electron

temperature is to reduce the rare gas pressure

in the lamp whilst increasing the supplied

electric power. Compared to the normal lamps

the lamp current is then considerably greater

and the electric field strength is substantially

the same or is somewhat lower. The wall load in

these lamps is of course higher.

It was furthermore found that with an efficient

production of ultra-violet radiation in highly

loaded lamps, there is not only a high ultra-violet

radiation density at the wall but also

the share of the radiation having a wavelength

of 185 nm is relatively higher than in normal

lamps. This unexpectedly high ratio between the

185 nm radiation and the 254 nm radiation

combined with the increased density of the total

ultra-violet radiation produced results in the

185 nm-load of the wall of such lamps being

considerably higher than in normal lamps."

33. The specification then identifies the invention:

"The invention is based on the recognition that

failure of the prior art lamps with high wall

load is not due to a low efficiency of the

conversion into ultra-violet radiation, as has

been generally assumed so far, but is due to the

luminescent materials used. The invention

provides suitable luminescent materials as a

measure for obtaining efficient, highly loaded

lamps. Consequently, the present invention

opens the way to an entirely new lamp type,

namely the compact low-pressure mercury vapour

discharge lamp which can replace the normal

incandescent lamp which is used in very great

numbers. As the efficiency of the low-pressure

mercury vapour discharge lamp is approximately 5

times greater than that of the incandescent

lamp, a very considerable saving in energy is

possible." (Emphasis added).

34. It seems to be common ground that the phrase "as a measure for" in the emphasised sentence of this extract is synonymous with "as a means of". So, the essence of the claimed invention is that it "provides suitable luminescent materials" as a means of obtaining efficient, highly loaded lamps. Although, according to the specification, the investigators surprisingly discovered that it is possible to convert electric power into ultra-violet radiation as efficiently in a highly loaded lamp as in a normal 40W/T12 lamp, and although the authors describe how this can be done, this discovery and information is not part of their claimed invention. Rather, in describing the invention, they start from the position that there is equal conversion efficiency between a 40W/T12 lamp and a highly loaded lamp, and address the question why, in that situation, highly loaded lamps are less efficient in producing visible light. The problem, they say, lies in the luminescent materials that have been used. The solution is to select suitable luminescent materials; and the purpose of the invention is to guide that choice, thus opening the way for a new type of lamp: the compact low-pressure mercury vapour discharge lamp.

35. The specification turns to embodiments. It says that, in a lamp according to the invention:

"a luminescent material is used which is, on the

one hand, highly resistant against 185 nm

radiation, that is to say it has only a very

slight decrease in the luminous flux (on

excitation by 254 nm radiation) owing to

irradiation by 185 nm rays and which, on the

other hand, has a high mercury resistance".

No luminescent material is identified. The specification goes on to set boundaries for acceptable short-term decrease of the luminous flux of the material when it is irradiated for 15 minutes:

"by radiation having wave lengths of mainly 185

nm and 254 nm with a radiation density between

150 and 500 W/m2 and with a ratio of 185 nm

power to 254 nm power between 0.20 and 0.40".

The specification refers to an apparatus for measuring this short-term decrease which is described and illustrated later in the document. The specification stipulates that the STD after 15 minutes "shall not be more than 5%". The embodiment proceeds to deal with electro-negativity, stating that:

"the luminescent material must not only satisfy

the requirement as regards the short-term

decrease but also the requirement for a higher

degree of mercury resistance."

"been found that the luminescent layer in highly

loaded lamps is exposed to a much greater number

of collisions with excited mercury atoms and

mercury ions than is the case in normal lamps

... A measure of the mercury resistance of a

luminescent material is found in the

electro-negativity (e.n) of the cations of the

luminescent material".

36. After stating that "it is now clear that mercury ... will attack luminescent materials whose cation has e.n >-1.9" the embodiment specifies an e.n of not more than 1.4, measured according to the Pauling table.

37. It is not necessary to detail all the remaining embodiments. A number reflect the various claims without identifying any particular luminescent material as meeting the specified criteria or being otherwise suitable for use in compact lamps. However, at page 13, the specification refers to an embodiment containing as luminescent material

"a red-luminescing, trivalent europium-activated

rare earth metal oxide having a composition

defined by the formula Ln2o3:pEu3+, where Ln

represents at least one of the elements Y, Gd

and Lu and where 0.01
luminescent oxides, which are known per se,

appear to have a very small short term decrease

and are highly resistant to mercury, so that

they can be used with great advantage in lamps

according to the invention".

The compound referred to in this embodiment is generally known as "YOX". This embodiment is reflected in claim 6.

38. The next embodiment refers to a group of luminescent aluminates, known per se under the sobriquet "CAT". It is said that these materials have a small short-term decrease and a good mercury resistance. Claim 7 is based on this embodiment.

39. The next embodiment contains a reference to a further group of luminescent aluminates, known per se and often called "BAM". They are said to have very low short-term decrease and good mercury resistance: see claim 8.

"The luminescent layer in a lamp according to

the invention may contain a luminescent material from

the group consisting of bivalent europium-activated

strontium tetraborate, lead-activated

barium disilicate, bivalent europium-activated

strontium chlorophosphate with an apatite

crystal structure, gadolinium metaborate

activated by cerium and terbium and gadolinium

borate activated by trivalent bismuth and

trivalent europium."

41. It is said that these materials have an excellent STD and that their mercury resistance "is very favourable": see claim 9.

42. The specification refers to two diagrams. Figure 1 illustrates "a low-pressure mercury vapour discharge lamp according to the invention". Figure 2 is a diagrammatic representation of the apparatus for measuring STD. Both diagrams are described at length. It is important to note that the STD specified in the claims (5% and 3%) is the decrease in luminosity of the luminescent material when measured by the particular apparatus in the way prescribed in this embodiment.

43. The specification refers to some tables. Table I sets out the electro-negativity, STD and luminous flux of ten different compounds, including YOX, CAT and BAM, as measured in discharge tubes with an inside diameter of 10.3 mm. The specification comments:

"It is clear that reducing the diameter, which

results in highly loaded lamps, in accordance

with the invention, is not accompanied by a loss

in column efficiency".

44. Table II sets out measurements of the luminous flux of lamps of 7.8, 10.3 and 14.5 mm inside diameter, containing "a blue luminescing material", BAM, after various numbers of hours of operation. Table III conveys similar information concerning YOX, a red luminescing material. Example 17 gives the same information for CAT, a green luminescing material, but only in respect of a 7.8mm tube. There is information in Tables IV and V (examples 18 to 26) regarding a mixture of YOX and CAT. Examples 27, 28, 29 provide some information about a mixture of YOX, CAT and BAM.

45. At the end of this section of the specification the words appear:

"It is clear that the abovementioned embodiments

only serve to illustrate the invention.

On the basis of the requirements formulated in

this description as regards short term decrease

and mercury resistance and by means of the

methods described for determining these

properties, a person skilled in the art can

easily ascertain which luminescent materials are

suitable for use in lamps according to the

invention. Furthermore it should be noted that

a luminescent material which, for example, does

not satisfy the requirements imposed on the

short-term decrease can be made suitable, for

example by optimizing the preparation of this

material. It is possible that a luminescent

material becomes sufficiently resistant to

attack by mercury by coating the material with a

protective layer."

46. The claims to the invention follow. Because of its central importance to the argument, I set out claim 1 in full:

"1. A low-pressure mercury vapour discharge lamp

having a vacuum-tight, radiation-permeable

envelope bearing a luminescent

layer and containing a gas filling

comprising mercury and a rare gas, and

means for maintaining a column discharge

in the gas filling, the power consumed

during operation by the column discharge

being at least 500 W per m2 surface area

of the luminescent layer, wherein the

luminescent layer contains a luminescent

material which has the property of having

at 254 nm-excitation a luminous flux

which, after the material has been

subjected for 15 minutes to ultraviolet

radiation consisting substantially of the

wavelengths 185 and 254 nm, having a

radiation density between 150 and 300 W/m2

and having a ratio of 185 nm power to 254

nm power between 0.20 and 0.40, is not

more than 5% lower than the initial

luminous flux of the material at 254 nm

excitation and measured under identical

circumstances, and wherein the combination

of cations (as hereinbefore defined) in the

luminescent material has an electro-negativity

of not more than 1.4."

(emphasis added)

47. Claim 2 refers to a lamp as claimed in Claim 1, but with an STD of not more than 3%, rather than the 5% mentioned in Claim 1.

48. Claim 3 refers to a lamp, as claimed in Claim 1 or Claim 2:

"wherein an electric field strength of 150 to

1000 V/m (volts per metre) is maintained in the

column discharge during operation of the lamp".

It is common ground between the parties that this claim envisages a compact lamp, the stipulated electric field strength being appropriate only to such a lamp. The earlier claims do not mention electric field strength.

49. Claim 4 refers to a lamp, as claimed in Claim 3:

"wherein the envelope has a tubular shape, whose

cross-section perpendicular to the axis of the

tube is substantially circular and whose inside

diameter is from 3 to 15 mm".

50. Claim 5 refers to a lamp, as claimed in Claim 1 or Claim 2, wherein an electric current of a current density of at least 0.5 A/cm2 (Amps per square centimetre) is maintained in the column discharge during operation of the lamp.

51. Claims 6, 7, 8 and 9 each claims a lamp as claimed in any one of Claims 1 to 5 wherein a particular luminescent material is used: in the case of Claim 6, YOX; in the case of Claim 7, CAT; in the case of Claim 8, BAM; and in the case of Claim 9 a compound from the group described above immediately before my reference to the diagrams.

The effect of the 1990 Act on patents granted under the 1952 Act

52. The primary Judge dealt at the commencement of his reasons for judgment with the question of the implications for patents granted under the 1952 Act of the repeal of that Act and its replacement by the 1990 Act. It is to that question that I turn first.

53. The 1952 Act was repealed by s. 230 of the 1990 Act. The 1990 Act contained transitional and savings provisions in Chapter 23. An important section in Chapter 23 is s. 233 which provides as follows:

"233(1) Subject to this Chapter and the

regulations, this Act applies in relation to a

standard patent or a petty patent granted under

the 1952 Act as if the patent had been granted

under this Act.

(2) A patent mentioned in subsection (1) does

not have effect in any place in which it did not

have effect immediately before the commencing day.

(3) Chapter 9 of this Act does not apply in

relation to a patent mentioned in subsection (1).

(4) Objection cannot be taken to a patent

mentioned in subsection (1), and such a patent

is not invalid, so far as the invention is

claimed in any claim, on any ground that would

not have been available against the patent under

the 1952 Act."

54. His Honour found that the purpose of sub-s. (4) is to ensure that a person who obtained a patent under the 1952 Act would not be exposed, by the repeal of that Act and the substitution of the 1990 Act, to an attack on the validity of the patent on a ground which would not previously have been available. His Honour found that a person who challenges the validity of the 1952 Act patent must do so under the 1990 Act, but that a ground of revocation available under that Act must also have been a ground of revocation under the 1952 Act. His Honour expressed this view subject to a qualification arising from reg. 23.26(1) of the Patents Regulations 1991 which provides that the 1952 Act applies to an action or proceeding, made or started under that Act and not finally dealt with or determined before the commencing day of the 1990 Act, in which the validity of a patent is disputed or which concerns infringement of a patent. As the present proceeding was instituted on 5 July 1991 (after the commencement of the 1990 Act on 30 April 1991), the regulation has no application to it so that it is not a proceeding commenced under the 1952 Act. His Honour therefore ignored the qualification. He found that to obtain a revocation order in the present case the respondent must make out at least one ground of invalidity under the 1990 Act which is also a ground of invalidity under the 1952 Act. He found that the purpose of s. 233(4) is to maintain the existing rights of holders of patents under the 1952 Act, but no more and that this purpose may be achieved by an interpretation:

"that requires an applicant for revocation under

the 1990 Act to establish, not only the facts

needed to make out the relevant ground under the

1990 Act, but also facts that would have led to

revocation upon an equivalent basis under the

1952 Act. That interpretation means that,

whilst 1952 Act patents remain in contention,

there must be a dual inquiry, the Court testing

the facts against the invoked ground of

invalidity, however described, in each Act. If

the proved facts satisfy the requirements of

each Act, s. 233(4) permits revocation under the

1990 Act of the 1952 Act patent; but not otherwise." (755)

55. It is plain that the Parliament did not intend by the repeal of the 1952 Act to leave the work of preservation of accrued rights and liabilities to the Acts Interpretation Act 1901 ("the Interpretation Act"). Chapter 23, in particular s. 233, evidences a plain intention to deal with the effect of the repeal and thus to express a contrary intention within the meaning of the introductory words of s. 8 of the Interpretation Act.

56. The initial Bill for an Act that became the 1990 Act did not include s. 233, which suggests that it was initially thought by parliamentary counsel that reliance would be placed upon the Interpretation Act to ensure continuation of relevant rights and liabilities under the 1952 Act; but obviously a change of mind and policy occurred. Clearly the rights of a patentee of a 1952 Act patent would have survived the commencement of the 1990 Act by the operation of s. 8(c) of the Interpretation Act. The patentee may have spent large sums of money developing the invention or, indeed may have assigned it for a large sum; obviously it would be not have been the intention of the Parliament to deprive the patentee or assignee of that benefit. But in the absence of Chapter 23 of the 1990 Act there would have been real doubt if a 1952 patent could have been revoked after the commencement of the 1990 Act. The language of s. 8 of the Interpretation Act probably would not have been a sufficiently strong vehicle to achieve the continued susceptibility of a 1952 Act patent to revocation: see Esber v The Commonwealth [1992] HCA 20; (1992) 66 ALJR 373 at 377; Norman v Federal Commissioner of Taxation (1963) 109 CLR at 16; and Mathieson v Burton [1971] HCA 4; (1971) 124 CLR 1 at 23.

57. In my opinion, the transitional and savings provisions in Chapter 23 of the 1990 Act are conclusive of the question of whether the 1990 Act is exhaustive of the grounds of revocation that may be relied upon with respect to a 1952 Act patent. The point becomes clear when reference is made to the relevant sections of the 1990 Act. The effect of s. 233(1) is that the 1990 Act applies in relation to a standard patent or a petty patent granted under the 1952 Act "as if the patent had been granted under this Act". A patent mentioned in sub-s. (1) does not have effect in any place in which it did not have effect immediately before the commencing day of the 1990 Act (sub-s. (2)). Chapter 9 is expressly excluded by sub-s. (3) from application in relation to a patent mentioned in sub-s. (1). Chapter 9 relates to re-examination by the Commissioner of complete specifications where the grant of a patent is opposed. Sub-section (4) states that objection cannot be taken to a patent mentioned in sub-s. (1) and that such a patent is not invalid, so far as the invention is claimed, in any claim on any ground that would not have been available against the patent under the 1952 Act.

58. Section 234(1) provides for the case where before the commencing day a patent application and provisional application had been lodged under the 1952 Act and the complete specification had not been lodged under that Act in respect of the application and the application had not been withdrawn; and states that, subject to Chapter 23 and the regulations, the 1990 Act applies in relation to the application on and after that day (that is the commencing day) as if it were a provisional application under the 1990 Act. Where, before the commencing day a patent application had been lodged under the 1952 Act and a complete specification or a petty patent specification had been lodged under that Act in respect of the application and the application had not been withdrawn or finally dealt with, subject again to Chapter 23 and the regulations, the 1990 Act is expressed to apply on or after that date in relation to the application as if it were a complete application made under the 1990 Act and in relation to the petty patent specification as if it were a complete specification filed under the 1990 Act in respect of the application (s. 234(2)).

59. Section 234(3) provides that Chapter 5 of the 1990 Act does not apply in relation to an application mentioned in sub-s. (2); but Part V of the 1952 Act as in force immediately before the commencing day continues to apply in relation to such application. Sub-section (4) provides that Chapter 9 of the Act does not apply in relation to applications mentioned in sub-s. (2) or patents granted under such applications. Sub-section (5) provides that objection cannot be taken to applications mentioned in sub-s. (2) or patents granted on such applications and that patents are not invalid, so far as the invention is claimed in any claim, on any ground that would not have been available against the applications or patents under the 1952 Act. Sub-section (6) provides that a petty patent specification to which sub-s. (2) applies cannot be amended under the 1990 Act so as to include more than one claim.

60. Section 235 provides for the application of the 1990 Act to applications, requests, actions or proceedings made or started under the 1952 Act and not finally dealt with or determined under that Act before the commencing day of the 1990 Act as if the applications, requests, actions or proceedings had been made or started under the corresponding provision of the 1990 Act. Provision is made by s. 236 that ss. 41 and 42 of the 1990 Act do not apply in relation to specifications lodged before 7 July 1987. Section 237 continues the effect of reports, orders or directions made or given under the 1952 Act and in force immediately before the commencing day as if they had been made or given under a corresponding provision of the 1990 Act.

61. Section 238, 239 and 240 provide for the continuance in office of persons holding office as Commissioner of Patents and Deputy Commissioner of Patents immediately before the commencing day (s. 238); for the Register of Patents under the 1952 Act to be taken as forming part of the Register of Patents under the 1990 Act; for the Register of Patent Attorneys under the 1952 Act to be taken to form part of the Register of Patent Attorneys under the 1990 Act (s. 239); and for the application of the 1990 Act to persons who were registered patent attorneys under the 1952 Act as if they had been registered as patent attorneys under the 1990 Act (s. 240).

62. These provisions in Chapter 23 lead to the conclusion that the express provision which the 1990 Act makes with respect to these matters must be read as exhaustive and that there is no room for the application of s. 8 of the Acts Interpretation Act. This is also consistent with the explanatory statement that accompanied the Bill which became the 1990 Act.

63. Counsel for the appellants argued that s. 233 plainly operates to permit revocation of a patent granted under the 1952 Act or the 1990 Act solely on grounds available under the 1990 Act, but only to the extent that those grounds are precise reflections of grounds of revocation previously available under the 1952 Act.

64. In my opinion the evident intent of s. 233(4) is to ensure that the grounds of revocation under the 1990 Act (which, though in some cases are expressed in different terms, are essentially the same as the grounds previously available under s. 100 of the 1952 Act) apply as the grounds for revocation of a 1952 Act patent; but with this important qualification, namely, that the elements of each ground of revocation under the 1990 Act apply only to the extent that they replicate in substance the elements that previously constituted a ground of revocation under the 1952 Act. Hence, if a ground of revocation under the 1990 Act omits an element which was a necessary part of a ground under the 1952 Act, the patentee has the benefit of it. On the other hand, if a ground under the 1990 Act contains an element not previously present under the 1952 Act, it cannot apply in aid of revocation of the 1952 Act patent. In short, a 1952 Act patentee is not to be worse off than he would have been if the 1952 Act had continued to operate, but he may be better off if the 1990 Act treats a former element of a ground of revocation as being no longer necessary.

65. A reading of the reasons for judgment of the primary Judge suggests that his Honour probably had the same approach in mind, though he did describe it as requiring a "dual inquiry". If his Honour meant by that expression that a ground of revocation under the 1952 Act still survives after its repeal by the 1990 Act, I respectfully disagree with him; but I do not think that is what his Honour intended by his observations on this question. His Honour's reasoning, as I understand it, was that an applicant for revocation under the 1990 Act of a 1952 Act patent must establish so many of the facts available as are needed to make out the relevant ground under the 1990 Act as were required under the 1952 Act. I think his Honour was in substance adopting the same approach as I have adopted.

66. I turn to the provisions of the 1990 Act relating to the grounds of invalidity asserted by the respondent.

67. The available grounds of revocation under the 1990 Act are set out in s. 138(3). Section 138 provides as follows:

"138(1) The Minister or any other person may

apply to a prescribed court for an order

revoking a patent.

(2) At the hearing of the application, the

respondent is entitled to begin and give

evidence in support of the patent and, if the

applicant gives evidence disputing the validity

of the patent, the respondent is entitled to reply.

(3) After hearing the application, the court

may, by order, revoke the patent, either wholly

or so far as it relates to a claim, on one or

more of the following grounds, but on no other ground:

(a) that the patentee is not entitled to the patent;

(b) that the invention is not a patentable invention;

(c) that the patentee has contravened a condition in the patent;

(d) that the patent was obtained by fraud, false suggestion or

misrepresentation;

(e) that an amendment of the patent request or the complete

specification was made or obtained by fraud, false suggestion or

misrepresentation;

(f) that the specification does not comply with subsection 40(2)

or (3)."

68. It is ground (b) "that the invention is not a patentable invention" with which this case is concerned. The expression "patentable invention" is defined by the 1990 Act's dictionary (a combination of s. 3 and Schedule 1 to the Act) as meaning "an invention of the kind mentioned in section 18". Section 18 provides:

"18(1) Subject to subsection (2), a

patentable invention is an invention that, so

far as claimed in any claim:

(a) is a manner of manufacture within the meaning of section

6 of the Statute of Monopolies; and

(b) when compared with the prior art base as it existed before

the priority date of that claim:

(i) is novel; and

(ii) involves an inventive step and

(c) is useful; and

(d) was not secretly used in the patent area before the priority

date of that claim by, or on behalf of, or with the authority of,

the patentee or nominated person or the patentee's or nominated

person's predecessor in title to the invention.

(2) Human beings, and the biological processes for their

generation, are not patentable inventions."

69. It is thus one of the essential features of a patentable invention that, when compared with the prior art base as it existed before the priority date of the claim, the invention is novel (s. 18(1)(b)(i)). Hence, lack of novelty deprives an invention of the status of being a "patentable invention" and constitutes a ground of revocation under s. 138(3)(b). It will be remembered that want of novelty is a ground of objection asserted by the respondent.

70. The respondent also asserts that the invention in suit did not involve an inventive step. Section 18(1) of the 1990 Act requires that a patentable invention is an invention that so far as claimed "when compared with the prior art base as it existed before the priority date of the claim ... involved an inventive step" (s. 18(1)(b)(ii)).

71. Section 7 of the 1990 Act deals with novelty and inventive steps in these terms:

"7(1) For the purposes of this Act, an invention

is to be taken to be novel when compared with

the prior art base unless it is not novel in the

light of any one of the following kinds of

information, each of which must be considered separately:

(a) prior art information (other than that

mentioned in paragraph (c)) made publicly

available in a single document or through

doing a single act;

(b) prior art information (other than that

mentioned in paragraph (c)) made publicly

available in 2 or more related documents,

or through doing 2 or more related acts,

if the relationship between the documents

or acts is such that a person skilled in

the relevant art in the patent area would

treat them as a single source of that information;

(c) prior art information contained in a

single specification of the kind mentioned

in subparagraph (b)(ii) of the definition

of 'prior art base' in Schedule 1.

(2) For the purposes of this Act, an invention

is to be taken to involve an inventive step when

compared with the prior art base unless the

invention would have been obvious to a person

skilled in the relevant art in the light of the

common general knowledge as it existed in the

patent area before the priority date of the

relevant claim, whether that knowledge is

considered separately or together with either of

the kinds of information mentioned in subsection

(3), each of which must be considered separately.

(3) For the purposes of subsection 92), the

kinds of information are:

(a) prior art information made publicly

available in a single document or through

doing a single act; and

(b) prior art information made publicly

available in 2 or more related documents,

or through doing 2 or more related acts,

if the relationship between the documents

or acts is such that a person skilled in

the relevant art in the patent area would

treat them as a single source of that information;

being information that the skilled person

mentioned in subsection (2) could, before the

priority date of the relevant claim, be

reasonably expected to have ascertained,

understood and regarded as relevant to work in

the relevant art in the patent area."

72. An invention that fails to involve an inventive step is therefore not a "patentable invention" and is revocable under s. 138(3(b).

73. Another ground of objection on which reliance is placed by the respondent is that the subject of the patent is not an invention that is a manner of manufacture within the meaning of s. 6 of the Statute of Monopolies (s. 18(1)(a)). The dictionary to the 1990 Act defines "invention" as meaning "any manner of new manufacture the subject of letters patent and grant of privilege within section 6 of the Statute of Monopolies, and includes an alleged invention".

74. Under the 1990 Act a "patentable invention" must be useful: see s. 18(1)(c). An invention which is not useful is revocable under s. 138(3)(b). I shall deal later, when considering each of the grounds of revocation upon which reliance is placed by the respondent, with the provisions of the 1952 Act that relate to them and their interaction with the provisions of the 1990 Act.

75. Reference must be made to s. 40 of the 1990 Act which sets out the formal requirements for provisional specifications and complete specifications. This case is concerned with a complete specification. Section 40 provides:

"40(1) A provisional specification must describe the invention.

(2) A complete specification must:

(a) describe the invention fully, including

the best method known to the applicant of

performing the invention; and

(b) where it relates to an application for a

standard patent - end with a claim or

claims defining the invention; and

(c) where it relates to an application for a

petty patent - end with a single claim, or

a single independent claim and not more

than 2 dependent claims, defining the invention.

(3) The claim or claims must be clear

and succinct and fairly based on the matter

described in the specification.

(4) The claim or claims must relate to one invention only."

76. The respondent asserts two infringements of s. 40: first, that the complete specification does not describe the invention fully (s. 40(2)(a)); and, second, that the claims of the complete specification are not fairly based on the matter described in the specification (s. 40(3)).

77. The applicants do not claim that the respondent has infringed any of Claims 6 to 9, the reason being that the luminescent material used in the respondent's lamp does not correspond with the material mentioned in any one of those claims. They assert that the respondent's luminescent material is a mixture of YOX, CAT and BAM, the three phosphors separately referred to in Claims 6, 7 and 8. But they accept that a mixture of the three phosphors is a different luminescent material from any of them individually and is therefore different from the relevant integer in any of these three claims.

78. At the trial the applicants asserted infringement of claims 1 to 5. It was not disputed at the trial that, if the case for infringement of claim 1 is established, infringement will also be established of claims 2, 3, 4 and 5. The argument on appeal and substantially at the trial centred on claim 1. Subject to one question of construction of claim 1, the primary Judge found that the Mirabella lamp answered the STD requirements of claim 1 and, provided the construction question is answered in favour of the appellant, there is infringement by the respondent of claim 1 and therefore claims 2, 3, 4 and 5. I turn to the question of construction of claim 1.

79. Questions of construction of claim 1 are critical to the issue of infringement. His Honour construed the words in the claim "wherein the luminescent layer contains a luminescent material ..." as meaning a luminescent layer which comprises a single phosphor or single chemical compound with defined properties. His Honour said that the word "contains" is ambiguous and that it may mean "comprises" or "includes". He looked to the body of the specification and concluded that the expression "contains a luminescent material" in claim 1 means comprises a single phosphor and not a mixture of phosphors. As the respondent's lamp embodies three phosphors, his Honour held that there was no infringement. This was the only basis on which it was contended before his Honour that there would not have been infringement, assuming the validity of the patent.

80. The relevant principles of construction of the claim where ambiguity is asserted are clear. If the meaning of a word in a claim is not clear then it is permissible to resort to the body of the specification to define or clarify the meaning of the word "without infringing the rule that clear and unambiguous words in the claim cannot be varied or qualified by reference to the body of the specification": see Interlego AG v Toltoys Pty Limited [1973] HCA 1; (1973) 130 CLR 461 per Barwick CJ and Mason J at 478-9 and the cases there cited. See also Decor Corporation Pty Limited v Dart Industries Inc (1989( AIPC 90-549 per Lockhart J at 38,827 and Sheppard J at 38,834.

81. The word "contains" is susceptible of more than one meaning. So far as relevant in this case it may mean "contains" in the sense of "comprises or consists of" or in the sense of "has within it", though, depending on the context, there is overlap between these concepts. The dictionaries attribute either meaning to the word. The word "material" is also capable of bearing more than one construction, again depending on the context in which it appears. It may mean "the substance of which a thing is made" or "composed of a component or constituent matter" as in a raw material; again, depending on the context, the two ideas may overlap. But the fact that a word may be susceptible of different meanings derived from its context does not mean that its meaning is ambiguous.

82. I respectfully differ on this question from the primary Judge. I do not discern ambiguity in the word "contains" where it appears in the relevant part of claim 1. It means that the luminescent layer has within it a luminescent material. The word "material", according to its ordinary English usage, may mean that the material is itself a mixture of other materials or compounds. It is perfectly apt to describe the resultant mixture as itself a material. I read the expression "contains a luminescent material" as meaning that the luminescent layer has within it a phosphor or mixture of phosphors. I see no warrant for reading the words "luminescent material" as being confined to a single phosphor or single chemical compound. Earlier in the claim, reference is made to the lamp the subject of the invention as having a "vacuum-tight radiation-permeable envelope bearing a luminescent layer and containing a gas filling comprising mercury and a rare gas ..." There the draftsman has used the word "containing" in the sense of having within it. In my view the reference a little later in the claim to the word "contains" is to be read in the same sense as the word "containing" which precedes it by some four lines. I discern no ambiguity. It is neither necessary nor permissible in my view to resort to the body of the specification in these circumstances.

83. However, if there is ambiguity in the words "contains a luminescent material" then resort to the body of the specification is justified. But if one proceeds down that path, I reach the conclusion that the luminescent layer has within it a single phosphor or a mixture of phosphors and not necessarily a single chemical compound or single phosphor.

84. Where necessary, the interpretation of the specification should be approached from the viewpoint of the skilled addressee in the art: Henricksen v Tallon (1965( RPC 434 at 443; General Tire and Rubber Co v Firestone Tyre and Rubber Co Ltd (1972( RPC 457 at 485; Nicaro Holdings Pty Ltd v Martin Engineering Co [1990] FCA 40; (1990) 91 ALR 513 at 523-4. In my opinion it is clear that the skilled addressee at the priority date, namely, 23 August 1977, would interpret the specification as referring to a luminescent layer which has within it a phosphor or a mixture of phosphors. The principal object of the invention was for a lamp which may be substituted for conventional incandescent lamps (see p 5 of the specification). The examples given in the specification contain examples 18, 19, 20, 27, 28 and 29, each of which involves mixtures of phosphors. Examples 27, 28 and 29 are CAT, BAM and YOX mixtures and it is said on p 25 of the specification that lamps made with mixtures of those three luminescent materials "only serve to illustrate the invention".

85. Also, it is clear from the evidence of Robert Bruce Sommerville, an electrical engineer experienced in the Australian fluorescent lamp industry, that the skilled addressee would recognize that the individual phosphors of the type mentioned in the specification, namely, CAT, BAM and YOX, would not by themselves give a "white light" sufficient to allow a lamp to be substituted for normal incandescent lamps. The phosphor CAT enables the production of a light of greenish-yellowish colour, BAM a bluish coloured light and YOX a reddish colour light; but it requires the mixture of the phosphors to give the white light which is sufficient to allow the invention to perform its primary function of substitution for normal incandescent lamps.

86. That the skilled addressee would at the date of publication interpret the specification as referring to a mixture of phosphors seems clear to me from the evidence of Dr Lowke, Dr Simpson and Mr Sommerville, although strictly the only witness whose evidence would be relevant on this question is the witness who was the skilled addressee in Australia, namely, Mr Sommerville. Mr Sommerville gave evidence that his knowledge of the three band lamps and the phosphors BAM and CAT came from the first appellant, particularly from a visit which he made to its establishment in Holland in 1976. On that visit he investigated the possibility of manufacturing three band lamps by Electric Lamp Manufacturers (Australia) Pty Limited ("ELMA"), his then employer, using the new phosphors which provided similar efficiency as the calcium halophosphates used in ELMA's standard fluorescent lamps, but which combined this with the superior colour rendering, previously only obtainable in so-called "Deluxe" lamps, which were also manufactured in Australia. Mr Sommerville concluded that their manufacture by ELMA would have been inadvisable since the skills of the present factory staff were inadequate and additional staff would have been required. Lamps employing three band phosphors such as CAT, BAM or YOX had never been manufactured in Australia. Mr Sommerville said that prior to about 1975 the choice in fluorescent lamps was between efficient lamps with less than optimum colour rendering, or where good colour rendering was required, so called deluxe lamps were used. Deluxe lamps employed phosphors which gave better colour rendering at the expense of efficacy. Later the so-called three band lamps and the phosphors CAT and BAM were developed to provide a lamp which combined colour rendering as good as the deluxe lamps with the efficacy of the high efficiency lamps.

87. In my opinion it is wrong to construe claim 1 from the viewpoint of the skilled addressee claiming a lamp with the luminescent layer which consists of one phosphor only or a single chemical compound. This would defeat the primary object of the invention. Certainly the claim includes this, but it includes also a mixture of phosphors. Otherwise the invention cannot be achieved. The invention is for a lamp which embodies phosphors suitable for highly loaded conditions with the requisite STD and EN characteristics to produce a white light.

88. As the Mirabella lamps produced by the respondent use three phosphors, namely, CAT, BAM and YOX phosphors, their use by the respondent infringes the first claim.

89. It is not necessary to consider the alternative submission put by counsel for the appellants that, if his Honour correctly construed the claim, the doctrine of mechanical equivalence applies and that the "pith and marrow" of the invention which underlies the mere accident of form has been pirated by the respondent: Clark v Adie (1875) 10 Ch App 667 at 675; Populin v H B Nominees Pty Ltd [1982] FCA 45; (1981) 59 FLR 37 at 41-43.

90. I turn to the grounds of invalidity alleged in the respondent's cross-claim.

Section 40: sufficiency of description and fair basing

91. The respondent asserted that the patent is invalid because the specification does not comply with the requirements of s. 40(2) of the 1990 Act; in particular, it does not describe the invention fully (s. 40(2)(a)) and the claims of the specification are not fairly based on the matter described in the specification (s. 40(3)). I have already stated the terms of s. 40(2) and (3). They are, relevantly, in essentially the same terms as those of s. 40(1) and (2) of the 1952 Act. The primary Judge found that, if either complaint is made out, it is effective to achieve revocation; and this finding was not challenged on appeal.

92. His Honour held that, based on the construction of Claim 1 which he preferred, namely, that a luminescent layer will contain only one luminescent material, the patent sufficiently or fully described the invention and that claims 1 to 5 were fairly based on the matters described in the specification.

93. On appeal, counsel for the respondent argued that the specification does not describe any of the following:

(a) the means of selecting luminescent material appropriate for

subjection to the prescribed STD and e.n measurements;

(b) the means of selecting from luminescent materials within the

described class (that is those that comply with the STD and e.n

criteria) the particular materials that will provide an efficient

lamp;

(c) the means of selecting luminescent materials outside those

disclosed and exemplified in the patent itself;

(d) the means of selecting luminescent materials covered by claims

6, 7 and 8, but not specifically exemplified in the specification;

(e) to the extent that the patent claims a luminescent layer

consisting of more than one luminescent material, the identity and

proportions of the remainder of the luminescent layer; and

(f) the method of preparation of luminescent materials.

94. Counsel for the respondent argued before us that, if, contrary to the findings of his Honour, the term "a luminescent material" in claim 1 is construed as including a mixture, then to the extent that the combinations of luminescent materials are claimed, and in the absence of any indication in the specification of how to choose other combinations, the only combinations which are fairly based on the patent are the precise combinations exemplified. In view of the construction of the words "a luminescent material" in claim 1 this question did not arise before his Honour.

95. The second argument advanced by counsel was that the claims are for a broad range of compounds, of which only a few are exemplified. To the extent that they claim luminescent material not known at the priority date, it was argued that they are speculative and not fairly based on the specification. The primary Judge said that the answer must be the same as with respect to the complaint of inadequate description, namely, if it is enough for claims 1 to 5 to refer to "a luminescent material, because a skilled addressee would understand that this refers to a phosphor with the characteristics mentioned by Dr Lowke (the former Head of Division of Applied Physics at the CSIRO) it does not matter that the relevant part of the body in the specification does the same."

96. In essence his Honour held that there would be a fair basing problem under s. 40 with the patent in suit if "a luminescent material" extended to a mixture of phosphors. His Honour noted that the body of the specification refers to five specified mixtures and that it contains no suggestion that other mixtures might constitute acceptable luminescent material. This finding was strongly criticized by counsel for the appellants. His Honour asked a series of questions, including "what might those mixtures be?", "Is it necessary that each ingredient in the mixture be luminescent, that is, be itself a phosphor?" and "Must the mixture as a whole meet the STD and e.n. criteria?" He found that it would require expertise beyond that of a skilled technician to know the answers to these questions because the answers might depend upon chemical reactions between the ingredients in the mixture. His Honour said that if the claim was fairly based upon a specification which fairly describes the invention, there would be no room for questions such as those which he posed.

97. Questions of sufficiency of instruction is a pure question of fact to be determined generally by the evidence of addressees of the specification: British Dynamite Co v Krebs (1896) 13 RPC 190 at 192. It is true that the specification must disclose the method of carrying out the invention and not merely the result to be obtained; but any general description is sufficient if in fact the desired result can be obtained with certainty and without invention: No-fume Limited v Frank Pitchford and Co Limited (1935) 52 RPC 231; Blanco White, Patents for Invention, 5th ed., at 4-505.

98. Assuming that "a luminescent material" (Claim 1) extends to a mixture of phosphors, and I think it does, the device which the patent teaches is useful if made only with single phosphors. Dr Lowke gave evidence that the device was useful if made only with single phosphors and not with mixtures. It is true that the specification discloses only five specific mixtures of phosphors, but these mixtures produce, according to the evidence, a satisfactory and efficient compact lamp. In my view this proceeds a fair distance down the path of indicating to the public that the device is useful if made either with single phosphors or with one or more of five specific mixtures of phosphors. As the specification teaches the requisite STD and e.n criteria, a reasonably competent skilled addressee (who could choose which among the available phosphors were worth subjecting to the STD and e.n tests specified by the patent (a conclusion which his Honour reached)), the reasonably competent skilled addressee would know the answer to the question posed by his Honour and mentioned above.

99. Mr Sommerville was aware in the 1970's of the three band lamps employing a mixture of three phosphors and his evidence was not challenged by the respondents. Persons skilled in the art would know what to do in relation to both single phosphors and mixtures of phosphors.

100. There is therefore no substance in this point made by the respondent.

101. His Honour made the finding that, if he was wrong on the question of construction of the expression "a luminescent material" in Claim 1, there would be an insufficient description for another reason, namely, that the nature of the remaining ingredients in the luminescent layer may be critical to overall compliance with the stipulated STD and e.n values and, therefore, the performance of the lamp; yet, he said they would be neither identified nor described. This too is essentially a statement of his Honour's perception of a fair basing problem.

102. In my opinion, if properly construed, the various claims envisage that a luminescent layer will contain only one luminescent material and that the specification is sufficient for a single phosphor, it must surely be sufficient for a mixture of phosphors because the same information provided in the body of the specification can be used to select, not just a single phosphor, but each constituent phosphor that constitutes the mixture.

103. Also, it was for the respondent to adduce evidence to establish its case of alleged insufficiency of description. It did not adduce such evidence so it must fail on this question: see British Dynamite Co v Krebs (1896( 13 RPC 190 at 192.

104. The respondent therefore fails in its case based on s. 40 of the 1990 Act.

105. His Honour held that the 1990 Act requires that the subject matter of a patent be an invention by definition under that Act, namely, that it is a "manner of new manufacture" within the meaning of s. 6 of the Statute of Monopolies (s. 18 and the Dictionary). He said that this position did not differ in substance from that pertaining under the 1952 Act (s. 100(1)(d)) and the definition of "invention" in s. 6 and its predecessor, the 1903 Act, which was considered in Commissioner of Patents v Microcell Limited [1959] HCA 71; (1958) 102 CLR 232.

106. The primary Judge found that the patent in suit does not claim the discovery by the patentee of any new property of phosphors, making them suitable for use in highly loaded low-pressure mercury vapour discharge lamps. He said that the luminescent qualities of phosphors had long been known and that a mere skilled technician would know which to try. He said that the patent did not claim that the patentee discovered that phosphors are subject to STD and that this inherent characteristic of phosphors was well known. His Honour found that the suggestion that the invention claimed in the patent in suit is not an "invention" or a "manner of new manufacture" is well founded and that accordingly the invention is not a "patentable invention" within the meaning of s. 18 of the 1990 Act. Being also within s. 100(1)(d) of the 1952 Act the patent is susceptible to revocation under s. 138(3)(b) of the 1990 Act.

107. This finding of his Honour was challenged by counsel for the appellants on a number of grounds. It was argued that the omission of the word "new" in the phrase "manner of manufacture", where appearing in s. 18(1)(a) of the 1990 Act was deliberate and is separate from the question of whether such manufacture be a new manufacture. It was argued that this distinction was recognized in certain of the cases including Re L and G's Application (1940) 58 RPC 21 and by the High Court in Microcell. It was said by counsel for the appellants that the 1990 Act now makes a careful distinction between the lack of an inventive step as such and the old "subject matter" objection which was used in circumstances where an objection of lack of inventive step was not otherwise available. The 1990 Act provides for novelty and obviousness in ss. 7 and 18 and contains a specific provision for manner of manufacture in the "industrial applicability" requirement in s. 18(a). Counsel for the appellants challenged his Honour's finding that this case did not involve the discovery of a new property of a known material and that "neither the patent nor the evidence suggests that the STD and e.n values stipulated in the patent reflect any discovery or new scientific insight by the patentees".

108. Counsel for the appellants argued that if, contrary to their submission, the test to be applied for determination of whether an inventive idea or step is disclosed in the specification, the evidence supports the contention that there was an inventive step comprising:

(a) the identification of the erroneous assumption that it was an

electrical discharge problem which prevented the making of a

useful compact lamp;

(b) the realization that there were criteria of performance in

phosphors, not recognized at that date, which would determine

their performance in compact lamps; and

(c) the experimentation analysis of the phenomena discovered by the

first appellant and the precise identification of those new

characteristics in the patent in suit in the STD and e.n

characteristics.

It was argued that the patent was the product of considerable research and was a "finding"; and that from the literature relied upon by the respondent itself it is clear that there was an inventive step and that what was done by the first appellant was not obvious at all.

109. The first of these questions relates to the proper construction of the 1990 Act which requires that the subject matter of a patent be an invention that is a "manner of new manufacture" within the meaning of s. 6 of the Statute of Monopolies (s. 18 and the Dictionary). I reject the argument advanced on behalf of the appellants that there was a substantial and deliberate change introduced into the 1990 Act between the concepts of "manner of manufacture" and what was said to be a separate question of whether such manufacture be a new manufacture. In my opinion the combination of s. 18(1)(a) of the 1990 Act and Schedule 1 thereto (where it defines "invention") continues in force the notion of "manner of new manufacture" present in s. 100(1)(d) of the 1952 Act. Although the language of the 1990 Act leaves something to be desired, that this was the intention of the Parliament appears sufficiently clearly from the explanatory memorandum which accompanied the Bill which became the 1990 Act (clause 18), the responsible Minister's Second Reading Speech and the ICAC Report recommendation number 12 which was accepted by the Government.

110. I turn to the important question whether an inventive idea or step is disclosed in the specification in suit which his Honour answered unfavourably to the appellants.

111. Although grounds of objection in patent law sometimes overlap, objections of want of novelty and obviousness are nevertheless essentially distinct from each other. Likewise, the requirement that a patentable invention be a manner of new manufacture is inherently distinct from the requirements of novelty, lack of obviousness, involving an inventive step and utility as required by s. 18 of the 1990 Act. See Blanco White, Patents for Inventors, 5th ed., paragraphs 4-901 to 4-908; Rickettson, Law of Intellectual Property, paragraph 48.17; R D Werner and Co Inc v Bailey Aluminium Products Pty Ltd (1989) 25 FCR 565; Lane Fox v The Kensington and Knightsbridge Electric Lighting Co Limited (1892) 9 RPC 413.

112. It is important to remember that the patent in suit does not claim a compact lamp per se; it claims the provision of suitable luminescent materials in the manufacture of compact lamps.

113. The primary Judge placed considerable reliance upon the Microcell case to support his conclusion that the subject matter of the patent in suit is not a manner of new manufacture. In Microcell the High Court considered various authorities including L and G's Application (1940) 58 RPC 21 where Morton J said at 23 that:

"The matter claimed is merely the use of a known

material, having its surface oxidised by a known

treatment, in the manufacture of known article,

for the reason that this material so treated,

possesses a known property rendering it useful

for this purpose." (at 248)

"Many valid patents are for new uses of old

things. But it is not an inventive idea for

which a monopoly can be claimed to take a

substance which is known and used for the making

of various articles, and make out of it an

article for which its known properties make it

suitable, although it has not in fact been used

to make that article before."

Their Honours held at 250 that the specification in suit did not disclose "more than a new use of a particular known product", that the properties of the materials to be used in the manufacture of the articles were well known as was the fact that those properties made them especially suitable for use in the article. Their Honours concluded at 251:

"We have in truth nothing but a claim for the

use of a known material in the manufacture of

known articles for the purpose of which its

known properties make that material suitable. A

claim for nothing more than that cannot be

subject matter for a patent, and the position

cannot be affected either by the fact that

nobody thought of doing the thing before, or by

the fact that, when somebody did think of doing

it, it was found to be a good thing to do."

115. The primary Judge found that this is not a case of a person discovering a new property in a known material which for the first time made it apparent that the material was suitable for a new use, in which case the discovery would amount to an invention and the claim of the patent would be for a manner of new manufacture. He said that the patent in suit:

"does not claim the discovery by the patentees

of any new property of phosphors, making them

suitable for use in highly loaded low-pressure

mercury vapour discharge lamps. The luminescent

qualities of phosphors had long been known.

Indeed, it is the applicants' case on

sufficiency of description - which I accept -

that the luminescent qualities of the relevant

phosphors were so well-known that it was

unnecessary to identify the phosphors to be

selected for STD testing and e.n. evaluation. A

mere skilled technician would know which to try.

Nor does the patent claim that the patentees

discovered that phosphors are subject to STD.

This inherent characteristic of phosphors was

well-known. Similarly it was known that the

mercury ions would attack substances with a

higher e.n than mercury (1.9) and zinc, which

has an e.n of 1.6. (The only explanation of the

patents selection of 1.4 as the appropriate e.n

limit was to stipulate a figure lower than that

of zinc.(" (811)

116. His Honour observed that the contribution to the art claimed by the patentees in relation to Claims 1 to 5 is to specify desirable STD and e.n limits for phosphors used in highly loaded lamps. No claim is made that a phosphor the STD or e.n of which exceeds one or both of those limits will be unsuitable for use in a highly loaded lamp; it is simply that the lamp will be less efficient than a conventional fluorescent lamp and presumably less competitive with incandescent lamps. His Honour said:

"Neither the patent nor the evidence suggests

the STD and e.n values stipulated in the patent

reflect any discovery or new scientific insight

by the patentees; rather they were figures

chosen to reflect the patentees' judgment as to

the degree of efficiency-loss from these two

causes which would be commercially acceptable. (812)"

"... it seems to me that it is not an invention,

or a manner of new manufacture, for someone to

specify the criteria required to be met, in the

manufacture of a known product from known

materials, in order to achieve vendibility. As

was said by Dixon CJ, Kitto and Windeyer JJ

in National Research Development Corporation v

Commissioner of Patents [1959] HCA 67; (1959) 102 CLR 252 at

262: 'Unless invention is found in some new

method of using the material or some new

adaptation of it so as to serve the new purpose,

no valid patent can be granted'."

118. It is not in dispute that each of the groups of luminescent materials, YOX, CAT and BAM, is admitted by the patentee to be "known per se". The patentee also admits that low pressure mercury vapour discharge lamps with high wall loads were known, with the object of obtaining small and compact lamps. I agree with the primary Judge that it would not be an invention for the patentee merely to use these known phosphors in known lamps with high wall loads, and that Microcell is closely in point here. See also NRDC v Commissioner of Patents [1959] HCA 67; (1959) 102 CLR 252 at 262.

119. I accept the correctness of the submission of counsel for the respondent that what the patentee has done in this case is to choose two desirable characteristics of the known phosphors and to claim lamps using all phosphors, present and future, possessing those characteristics. The evidence of Dr Verhaar, a scientist employed by the first appellant, makes this point in clear terms. The two desirable characteristics of the known phosphors which were admittedly known were:- (a) short term initial lumens depreciation, or "short term decrease",as it is described in certain of the evidence (that is to say in a lamp according to the invention, luminescent material must satisfy the requirement of short term decrease); and (b) a lamp according to the invention must also satisfy the requirement of a higher degree of mercury resistance or long term maintenance. I accept the correctness of counsel for the respondent's submission that the patentee has essentially "formulated requirements" "as regards short term decrease and mercury resistance" (to use the words of the specification (at 26) "formulated requirements") and claimed them as limitations on the luminescent material. I agree with his Honour's finding that this is not an invention.

120. Many of the submissions made by counsel for the appellants on this point blurred the distinction between the requirement that the invention be a manner of new manufacture and obviousness. The respondent did not press its case at the trial (nor therefore on appeal) on obviousness, no doubt, at least in part, because the respondent could not establish that what is described in the evidence as the Vrenken Article was common general knowledge in Australia.

121. Essentially what the patentee claims in the patent in suit is a lamp that has two basic characteristics, namely, short term depreciation which is related to efficiency of light and electronegativity which is a function of a relevant chemical formula. This is not a patentable invention as his Honour correctly found. His Honour carefully drew the distinction between the use of the word "inventive" in the sense of obviousness and a manner of new manufacture.

122. As mentioned earlier the expressions "manner of new manufacture" and "manner of manufacture" in this branch of the law under the 1990 Act mean the same thing and involve the same concepts as they have been understood and developed since 1623 when the Statute of Monopolies was passed.

123. In R D Werner and Co Inc v Bailey Aluminium Products Pty Limited (1989) 25 FCR 565 I examined the history of the law of patents bearing on the distinction between novelty, obviousness and manner of new manufacture, distinctions which were developed in comparatively recent times. The court does not enquire too finely or minutely into the degree of ingenuity involved to determine whether or not an invention is patentable once it is satisfied that some independent invention has been applied. It is sufficient that there has been some substantial exercise of the inventive faculty: Werner v Bailey per Lockhart J at 574. As to this distinction see also the judgment in Werner v Bailey of Gummow J at 591-602.

124. In my opinion his Honour correctly held that the subject manner of the patent in suit is not an invention.

125. The appellants succeeded on this point before the primary Judge. His Honour found that the evidence established the publication before the priority date of a great deal of relevant information. He considered the paper called "Verstegen 2" which referred to the discovery of "a new class of phosphors based on hexagonal aluminate host lattices", where the authors of the paper said that "several representatives" of this class were suited to application in fluorescent lamps. The identified phosphors included BAM, CAT and YOX. Reference was made to the "new generation" lamps enabled by the new phosphors, which would be superior both in luminous output and colour rendering capability. The authors claimed that an advantage of the new phosphors was their high efficiency at elevated temperatures, making them suitable for high-loaded lamps in which the mercury pressure is amalgam-regulated. The lamp, according to the invention, is such a lamp. The paper called "Verstegen 1" gives considerable further detail about the phosphors, as does the 1976 article by another of the first appellant, Mr L E Vrenken. Mr Vrenken specifically mentions BAM, CAT and YOX as being "well suited for application in fluorescent lamps". He also makes the point that the new phosphors are suitable for compact lamps:

"The use of the new phosphors is not restricted

to 40W T12 lamps. An advantage of the rare

earth activated phosphors is their high

efficiency at elevated temperatures, which makes

them suitable for those situations where the

bulb wall temperature is relatively high e.g.

with normal lamps in closed luminaries or with

highly loaded lamps".

126. The primary Judge accepted the argument of counsel for the appellants that none of the prior publications reveal the actual wall loading that could be expected in a compact lamp. He applied the words of Sach LJ in General Tire and Rubber Co v Firestone Tyre and Rubber Co Ltd (1972) RPC 457 at 485-6:

"a signpost, however clear, upon the road to the

patentee's invention will not suffice. A prior

inventor must be clearly shown to have planted

his flag at the precise destination before the patentee."

127. The second reason for his Honour's rejection of the respondent's argument relating to novelty arose out of the fact that the phosphors referred to in the three articles are not limited to BAM, CAT and YOX. His Honour posed the relevant question as being whether an implementer of the teaching contained in one of the prior publications would "inevitably" breach the subject patent (the "reverse infringement test": see General Tire and Rubber per Sachs LJ at 486). His Honour said that if that person used BAM, CAT or YOX or a mixture of two or more of them in a 500 W/m2 lamp that patent would be breached. He held:

"But, although these three phosphors take the

limelight, there are other phosphors amongst the

group discussed in the article. As I understand

the evidence, they do not all have STD and e.n

characteristics within the claims of the patent.

So a person could implement the teaching of the

prior publication but not transgress the limits

of the monopoly claimed in this patent."

128. The respondent's attack upon his Honour's findings have not been made out so, in my opinion, the primary Judge's findings stand.

129. His Honour held that the invention disclosed in the patent in suit was useful. He found that the specification sufficiently describes invention.

130. Counsel for the respondent challenged this finding of his Honour. It was argued that where the claim is for a class of chemical substances, specified in chemical terms, there can normally be no room for a construction that would exclude any of them, however obviously useless. Accordingly, if any of them is proved to be useless for the patentee's purposes, the claim is invalid. The duty of the patentee is to formulate his claim in such a way as to define with clarity the area of his monopoly. Counsel for the respondent argued that in the patent in suit many phosphors would satisfy the STD and e.n measurements which would not be useful for the purposes stated and that the patent does not teach any methods of preparation of phosphors, which may affect the STD measurements.

131. His Honour adopted the following passage from Lahore and Ors at para. 1.5.072 of Patents Designs and Trademarks Law as an accurate statement of what is required of a patent for it to be useful:-

"What is required is that the invention should

enable the addressee to achieve the result

claimed by the patentee as being attainable

through the use of that invention. If the

claimed invention provides a product or process

better than what was previously known, as good

but cheaper, an alternative method of achieving

an old result or it gives the public a useful

choice, that is enough. It is not necessary

that the invention should be a commercial

success unless that is promised by the patentee

and it is immaterial, for the purposes of

judging utility, that the invention has never

been used; it is enough that it could have been."

132. His Honour expressed the view that the specification in suit sufficiently described the invention and he approached the question of utility on the basis that an issue as to utility does not arise unless the patent is formally valid which means, amongst other things, that it sufficiently describes the invention and describes something that is in truth an invention and a manner of new manufacture. His Honour found that a skilled addressee would know which phosphors, amongst the range of known phosphors, have the necessary qualities, sufficient luminescence and appropriate visual spectrum, to make them worth testing and would appreciate the necessity for proper preparation. In view of these conclusions his Honour rejected the argument that the invention lacked utility.

133. In my opinion his Honour's findings have not been shown to be in correct and should not be disturbed.

134. In the result, I differ from the primary Judge's construction of the critical words in Claim 1 of the patent in suit; so that if the cross-claim had failed there would have been infringement by the respondent. Also, I take a different view from his Honour on the question of fair basing. The central finding on the cross-claim of his Honour was, however, with respect to the question of invention and manner of new manufacture, a finding with which I agree. The orders made by his Honour should stand.

135. As to costs of the proceedings at first instance I would vary the primary Judge's order (namely that the appellants must pay the costs of the respondent, both of the principal proceeding and the cross-claim) because the appellants have succeeded on the question of construction of the claims of the patent in suit. I do not think their limited success on the questions of fair basing should alter the result as to costs either at first instance or on appeal. I would order the appellants to pay one-half of the cost of the respondent of the principal proceeding at first instance and to pay the costs of the respondent of the cross-claim. As to the costs of the appeal, I would order the appellants to pay two-thirds of the cost of the respondent of the appeal.

136. By consent on 16 July 1992 a judge of the Court ordered that orders 1 and 2 made by the primary Judge on 14 July 1992 (namely, that the application be dismissed and that the patent in suit be revoked) be varied so as to state in each case that the order is made without prejudice to the right of the respondent to recover damages pursuant to the undertakings of the applicants given to the Court on 10 July 1991 (with any extensions thereof).

137. Accordingly, I would make the following orders:

1. That the order for costs made by Wilcox J be varied by ordering

the appellants to pay two-thirds of the costs of the respondent,

of the principal proceeding and the cross-claim;

2. Otherwise, the appeal be dismissed;

3. The appellants pay two-thirds of the cost of the respondent of

the appeal.

BURCHETT J In this appeal, subject to what follows and except with respect to the question whether the patent is valid in so far as it relates to a new "manner of manufacture within the meaning of s. 6 of the Statute of Monopolies" (see s. 18(1)(a) of the Patents Act 1990), I agree generally with the reasons for judgment of Lockhart J In these reasons, I shall confine myself, first, to the particular question I have mentioned; secondly, to some aspects of the principles applicable to the construction of a complete specification; and thirdly, to some comments on the question of novelty, as it arises in this case.

2. The learned trial judge drew attention to the terms of s. 18(1)(a) of the Patents Act 1990 and the definition of "invention" contained in what is called the "Dictionary" in schedule one of that Act. Reading these provisions together, he concluded that the subject matter of a patent must be an invention that is a "manner of new manufacture" within the meaning of s. 6 of the Statute of Monopolies. He added that substantially the same situation obtained under the Patents Act 1952, by virtue of the definition of "invention" in s. 6 and the terms of s. 100(1)(d).

3. Counsel for the appellants pointed out that the Patents Act 1990, by s. 138, provides relevantly a single ground for revocation, "that the invention is not a patentable invention"; but nevertheless, by s. 18, provides a modified form of the old division of that question into a series of separate issues - whether the claimed invention is "a manner of manufacture within the meaning of s. 6 of the Statute of Monopolies", whether it is novel, whether it involves an inventive step, whether it is useful, and whether it was secretly used. It was submitted that the question whether the invention was a manner of new manufacture was deliberately omitted.

4. It would be very odd if Parliament, having carefully set the parameters for a determination of the questions of novelty and obviousness (see s. 18(1)(b) and s. 7), intended either to provide for an unfettered determination of the same issues by virtue of the use of the word "new" in the definition of "invention", or to provide for a duplication, by virtue of that definition, of the very questions of novelty and obviousness as set by the statute. But it does not follow that the question of new manufacture is excluded from s. 18. That is because an interpretation is open which, without evading or duplicating the statutory provisions in respect of novelty and obviousness, allows meaning to be given to the expression "manner of new manufacture". That this was the intention seems to me to follow, not only from the language of s. 18 read in the light of the definition of "invention", but also from a consideration of the structure of the Act as a whole, in the light of the history of the development of patent law, and of the explanatory memorandum and the report of the Industrial Property Advisory Committee of 1984 entitled "Patents, Innovation and Competition in Australia", to which the explanatory memorandum informs us the Act was a response. Under the heading "Manner of Manufacture", the Committee pointed out that the concept of s. 6 of the Statute of Monopolies involved three primary tests: "The invention must be new, inventive (not obvious), and capable of industrial application." The Committee went on to draw attention to the fact that under the existing law (the 1952 Act), as was in fact to be the position under the 1990 Act, the requirements of novelty and invention were the subject of express grounds of invalidity, while "the industrial capability requirement" arose from the reference to s. 6 of the Statute of Monopolies and the words "manner of ... manufacture". The Committee commented: "This concept involves little more than that an invention must belong to the useful arts rather than the fine arts." It added:

"Over the last 350 years the courts have interpreted and

applied the concept of manner of manufacture in an

expanding and generally non-selective fashion, except for a

tendency to focus on manufacturing industry, more or less

in accordance with the expansion of technology and

industrial activity, and the needs and understanding of the times."

5. The Committee concluded its discussion on this point with the following remarks:

"Finally, it has often been suggested that the reference to

'manner of manufacture' as the touchstone of patentability

should be replaced by an explicit statement of what is and

what is not patentable. For example, a codified definition

was substituted in the UK Patents Act for the former

reference to manner of manufacture to bring that

legislation into line with the European Patent Convention.

We consider that the existing concept operates quite

satisfactorily. It has the advantage of being underpinned

by an extensive body of decided case law which facilitates

its application in particular circumstances. At the same

time it has, in the past, exhibited a capacity to respond

to new developments. To replace it with a codification

would be likely to produce far more problems, with

attendant costs, than it would solve."

I note that although this passage refers to the different approach in the current United Kingdom legislation, the report of the Departmental Committee on the Patents and Designs Acts (1931), in the United Kingdom, contained a recommendation in terms similar to those of the passage I have cited from the Australian report. In the Australian report, the final recommendation on this matter took the following form:

"WE RECOMMEND that the present threshold test of

patentability by reference to section 6 of the Statute of

Monopolies and to the expression 'manner of new

manufacture' be retained, without specific legislative

inclusions or exclusions."

6. The explanatory memorandum, in relation to s. 18, refers expressly to the definition of "invention" and to the requirement "that an invention, in order to be patentable, must be a 'manner of manufacture'", and comments that this

"invokes a long line of UK and Australian court decisions.

... The Government accepted the Industrial Property

Advisory Committee's recommendation that this flexible

threshold test of patentability be retained in preference

to adopting a more inflexible codified definition."

7. Accordingly, I think it is appropriate to look at the position established by the case law prior to the enactment of s. 18. The case law did lay down a threshold test of patentability by reference to the expression "manner of new manufacture". The answer to the question posed by that test, however, as the High Court pointed out in National Research Development Corporation v. Commissioner of Patents [1959] HCA 67; (1959) 102 CLR 252 at 269, does not depend upon verbal analysis, but rather upon whether the claimed invention falls within "the whole category under which all grants of patents which may be made in accordance with the developed principles of patent law are to be subsumed". And "(t)he right question is: 'Is this a proper subject of letters patent according to the principles which have been developed for the application of s. 6 of the Statute of Monopolies?'" (Cf. Joos v. Commissioner of Patents [1972] HCA 38; (1972) 126 CLR 611 at 617.) That question, it may be added, ought not to be answered on the basis of any narrow view of what is a proper subject of letters patent. For, as Dixon J said in Maeder v. Busch [1938] HCA 8; (1938) 59 CLR 684 at 706 (and see National Research Development Corporation at 255), "a widening conception of a manner of new manufacture has been a characteristic of the growth of patent law".

8. When the question is seen as a preliminary question whether the application for a patent falls within the category of things with which patent law is concerned, or whether its subject "is outside the whole scope of what is known as invention" (Commissioner of Patents v. Microcell Limited [1959] HCA 71; (1959) 102 CLR 232 at 247), the difficulty of apparent internal conflict within s. 18 disappears. If it can be said that what is proposed as an invention is not a proper subject of letters patent, that is enough. This proposition, as was said in Microcell at 246, will include the case of a specification of which it can be said that it is "clear on its face that the specification discloses no inventive step". But where, although it is not clear on the face of the specification that there is no inventive step, an attack is launched on the basis that there is no inventive step (that is, on the ground of obviousness), or on the ground of novelty (which is what Terrell on the Law of Patents, 13th ed. (1982) at para. 2.02 takes to be the real point of "new" in the phrase "manner of new manufacture"; and see also T.A. Blanco White, Patents for Inventions, 5th ed. (1983) para. 4-904), the attack is not made under s. 18(1)(a), but under s. 18(1)(b) and s. 7. Hill J took a similar view of the position under the Patents Act 1952, in Advanced Building Systems Pty Ltd v. Ramset Fasteners (Aust) Pty Ltd (unreported, 23 April 1993, at 43-44). This conclusion is important, as a general proposition, because of the establishment by s. 18(1)(b) and s. 7 of the limits of the grounds, and, textually, it is emphasized by the draftsman's omission of the word "new" from para. (a). In the particular circumstances of the present case, it has special significance because any reliance on the ground of obviousness was expressly abandoned at the hearing, and lack of novelty has not been established.

9. It is, of course, not possible to discuss whether the specification is concerned with a proper subject of letters patent, or whether on its face it discloses no inventive step, except by reference to the specification itself. Having regard to the arguments which have been advanced in this case, there is particular importance in understanding what the specification actually states. Unfortunately, the specification is quite long, but I think a substantial part of it should be set out verbatim. The title is: "COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: 'LOW-PRESSURE MERCURY VAPOUR DISCHARGE LAMP'." The specification then contains the following:

"The invention relates to a low-pressure mercury vapour

discharge lamp having a vacuum-tight radiation-permeable

envelope provided with a luminescent layer, a gas filling

comprising mercury and a rare gas, and means for

maintaining a column discharge in the gas filling, the

power consumed by the column being at least 500 W/m2

surface area of the luminescent layer.

Low-pressure mercury vapour discharge lamps are

radiation sources which are used on a very large scale both

for general illumination and for special purposes (for

example, activating photochemical processes), because they

convert the electric power supplied very efficiently into

radiation. In general these lamps consist of a tubular

envelop which may be straight or curved, for example in the

form of a circle or U-shaped. This envelope contains a gas

mixture comprising mercury and one or more rare gases in

which a column discharge is produced. This column

discharge is maintained by supplying electric energy to the

gas mixture, usually through two electrodes. Mainly

ultra-violet radiation is produced in the discharge, a

comparatively small part of which radiation has wavelengths

of approximately 185 nm, the greatest part of the radiation

having wavelengths of approximately 254 nm. This

ultra-violet radiation is converted by means of a luminescent

layer located on the inner wall of the lamp envelope, into

radiation having a longer wavelength and a spectral

distribution, depending on the luminescent material used,

in the near ultra-violet or in the visible part of the

spectrum.

One of the commonest types of low-pressure mercury

vapour discharge lamp is the so-called 40 W/T12-lamp

consisting of a straight tube which has a length of

approximately 1.20 (meters) and an internal diameter of

approximately 37 mm, and consuming a power of approximately

40 W. In general this lamp is operated with a lamp current

of approximately 400 mA and an electric field strength in

the column of approximately 80 V/m. The temperature of the

coldest spot of the envelope of such a lamp which is

free-burning in air is, in these circumstances approximately

40 degrees, at which temperature there is a mercury vapour

pressure of approximately 6x10-3 torr in the lamp. It

appeared that these circumstances are substantially optimal

as regards the production of ultra-violet radiation. Other

frequently occurring lamp types have in operation lamp

current, electric field and mercury vapour pressure values

which correspond to the above-mentioned values or do not

deviate much therefrom. The wall load of these lamps, that

is to say the power input of the column per surface unit of

the luminescent layer, has a value of approximately 300

W/m2 in these lamps.

Low-pressure mercury vapour discharge lamps have

already been made, wherein a considerably higher wall

load, namely 500 W/m2 is applied, so that the electric

power input per volume unit of the lamp becomes

considerably greater. This was done in the first place

with the object of obtaining small and compact lamps.

German Offenlegungsschrift 2,109,898, for example,

discloses small lamps having wall loads up to approximately

2500 W/m2. The electric field strength in these lamps is

higher than in the normal lamps and has, for example, a

value of the order of 600V/m. In the second place, the use

of high current densities (from 0.5 to 25 A/cm2) enabled

the production of lamps whose wall is loaded very highly.

These lamps are, for example, disclosed in United States

Patent Specifications 3,778,662 and 3,679,928. Wall loads

of the order of 25,000 W/m2 may occur in these lamps.

A great drawback of the prior art lamps with a

relatively high wall load is that the efficiency of the

lamp, that is to say the radiant flux or luminous flux of

the useful radiation emitted by the luminescent layer (the

output of useful radiation per unit of electric power

applied to the lamp) appears to have a low value. In

particular this efficiency is considerably lower than that

of the normal lamp (for example the 40 W/T12-lamp). This

drawback is especially felt with the compact lamps and is

one of the reasons that this lamp type, which might offer

great advantages for practical applications, for example as

a substitute for normal incandescent lamps, has as yet not

been introduced. The reason why it appeared to be

impossible to produce lamps having a high power input per

unit volume and with an efficiency comparable to that of

the normal lamps was not understood. Also known insights

as regards the optimum mercury vapour pressure (which

appears to be higher for lamps which are loaded to a

greater extent, for example to 0.75 Torr at a temperature

of the coldest spot of the lamp of 120 degrees C) and means for

controlling the mercury vapour pressure (amalgams etc) did

not lead to the desired result. It has, therefore, been

considered that producing a compact lamp, for example by

reducing the diameter whilst maintaining the electric power

supplied must inevitably be accompanied by loss in

efficiency.

The invention has for its object to provide low-pressure

mercury vapour discharge lamps which in operation

has (have) a high density of the consumed power and a high

radiation efficiency, so that on the one hand compact lamps

with an efficiency substantially equal to that of the

normal low-pressure mercury vapour discharge lamps and, on

the other hand, lamps having high current densities with an

improved radiation efficiency become available.

The invention provides a low-pressure mercury vapour

discharge lamp having a vacuum-tight radiation-permeable

envelope bearing a luminescent layer and containing a gas

filling comprising mercury and a rare gas, and means for

maintaining a column discharge in the gas filling, the

power consumed during operation of the lamp by the column

discharge being at least 500 W/m2 of the surface area

of the luminescent layer, wherein the luminescent layer

comprises a luminescent material which has the property of

having at 254 nm excitation a luminous flux, which after

the material has been subjected for 15 minutes to

ultra-violet radiation consisting substantially of the

wavelengths 185 and 254 nm, having a radiating density

between 150 and 500 W/m2 and having a ratio of 185 nm power

to 254 nm power between 0.20 and 0.40, is not more than 5%

lower than the initial luminous flux of the material at 254

nm excitation and measured in identical circumstances, and

wherein the combination of cations (as hereinafter defined)

in the luminescent material has an electronegativity of not

more than 1.4.

During the investigations which led to the invention,

it was found that an efficient conversion of the electric

power into ultra-violet radiation is possible in a highly

loaded lamp. It was surprisingly found that the efficiency

of this conversion can be substantially equal to that of

the normal 40W/T12 lamp. It was found to be a prerequisite

that the electron temperature in the highly loaded lamp

assumes a value which is not lower, and is, preferably

higher than that in the normal lamp. Various measures are

possible to achieve this. Starting, for example, from the

normal lamp, the required high electron temperature is

maintained if the discharge tube has a smaller diameter,

while the electric power supplied to the lamp is kept

substantially constant. Compared to the normal lamps, the

electric field strength is then higher, the lamp current is

lower and the wall load is higher than in the normal lamps.

Experiments showed that said high efficiency of the

conversion into ultra-violet radiation can also be obtained

with very low diameters of the discharge tube (from one to

a few mm). Another measure which makes it possible to

maintain a high electron temperature is to reduce the rare

gas pressure in the lamp whilst increasing the supplied

electric power. Compared to the normal lamps the lamp

current is then considerably greater and the electric field

strength is substantially the same or is somewhat lower.

The wall load in these lamps is of course higher.

It was furthermore found that with an efficient

production of ultra-violet radiation in highly loaded

lamps, there is not only a high ultra-violet radiation

density at the wall but also the share of the radiation

having a wavelength of 185 nm is relatively higher than in

normal lamps. This unexpectedly high ratio between the 185

nm radiation and the 254 nm radiation combined with the

increased density of the total ultra-violet radiation

produced results in the 185 nm-load of the wall of such

lamps being considerably higher than in normal lamps.

The invention is based on the recognition that

failure of the prior art lamps with high wall load is not

due to a low efficiency of the conversion into ultra-violet

radiation, as has been generally assumed so far, but is due

to the luminescent materials used. The invention provides

suitable luminescent materials as a measure for obtaining

efficient, highly loaded lamps. Consequently, the present

invention opens the way to an entirely new lamp type,

namely the compact low-pressure mercury vapour discharge

lamp which can replace the normal incandescent lamp which

is used in very great numbers. As the efficiency of the

low-pressure mercury vapour discharge lamp is approximately

5 times greater than that of the incandescent lamp, a very

considerable saving in energy is possible. In a lamp

according to the invention a luminescent material is used

which is, on the one hand, highly resistant against 185 nm

radiation, that is to say it has only a very slight

decrease in the luminous flux (on excitation by 254 nm

radiation) owing to irradiation by 185 nm rays and which,

on the other hand, has a high mercury resistance.

It is known that subjecting a luminescent material to

185 nm radiation has in general even after a very short

period of time a detrimental effect on the luminous flux of

the luminescent material. As a measure of the resistance

to 185 nm radiation the so-called short term decrease is

used, which in this description is understood to mean the

decrease (in %) in the luminous flux of the material, when

excited by 254 nm radiation) (sic) as the result of an

irradiation for fifteen minutes by radiation having wave

lengths of mainly 185 nm and 254 nm with a radiation

density between 150 and 500 W/m2 and with a ratio of 185 nm

power to 254 nm- power between 0.20 and 0.40. An

arrangement for determining the short term decrease as well

as the value of this decrease for some luminescent

materials is known from "Illuminating Engineering" 59

(1964), pages 59-66. Such an arrangement will be described

in greater detail below. Owing to the high density of 185

nm radiation, high requirements are imposed in lamps

according to the invention on the short term decrease of

the luminescent material. This decrease shall not be more

than 5%. It has been found that for a higher value of this

decrease, lamps are obtained which furnish an unacceptably

low luminous flux after having burned for the few minutes

which are required for obtaining a steadily burning lamp;

in practice the short term decrease has already taken place

when the luminous flux of the lamp is measured at 0 hour.

In a lamp according to the invention the luminescent

material must not only satisfy the requirement as regards

the short term decrease but also the requirement for a

higher degree of mercury resistance. It has, namely, been

found that the luminous layer in highly loaded lamps is

exposed to a much greater number of collisions with excited

mercury atoms and mercury ions than is the case in normal

lamps. The highly energetic mercury atoms and ions can be

absorbed at the surface of the luminescent layer and/or

react with the luminescent material. Consequently a

darkening of the luminescent layer occurs which

considerably reduces the luminous flux of the lamp. A

measure of the mercury resistance of a luminescent material

is found in the electro-negativity (e.n.) of the cations of

the luminescent material. In this description and the

claims, cations is defined to mean the metals from the

series 1A, 1B, 2A, 2B and 3B of the periodic system of

elements as specified in "Handbook of Chemistry and

Physics", Cleveland (Ohio). The further elements are here

considered as anions or anion-forming elements. The values

of the electronegativity (e.n.) of the elements are given

in L. Pauling "The Nature of the Chemical Bond", New York

(1945). If the elements are arranged in a series on the

basis of an increasing value of the e.n. the so-called

electromotive series of the elements is obtained. In

principle a certain element can displace all elements from

this series having the same or a higher value for the e.n.

from a compound. It is now clear that mercury (which has

an electronegativity of 1.9) will attack luminescent

materials whose cation has e.n.>- 1.9 (these cations are

equally noble or nobler than mercury). It was (has) now

been found that the cation of a luminescent material

suitable for lamps according to the invention must have a

relatively low e.n., namely not more than 1.4. This can be

explained from the fact that the mercury in the discharge

plasma is richer in energy than neutral mercury and from

the fact that the number of times the mercury collides with

the luminescent layer is high. It was found, for example,

that a luminescent material containing zinc (e.n. = 1.6) as

a cation, which in normal lamps shows some mercury attack

only after a relatively long operating period can

definitely not be used in highly-loaded lamps because the

luminescent layer is already markedly darkened after the

lamp has burnt for a period of from some minutes to some

hours. If a luminescent material contains several cations,

for example if the element used as an activator is a

cation, the combination of cations should have an e.n. of

not more than 1.4, which in the description and claims is

defined to mean, the weighted average of the

electronegativities of the cations shall not be more than

1.4. In that case it is possible that a small part of the

cations in the luminescent material per se has for itself

an e.n. higher than 1.4.

Preference is given to low-pressure mercury vapour

discharge lamps according to the invention containing a

luminescent material which has the property that it

furnishes, after the above-described ultra-violet

irradiation for 15 minutes, a luminous flux which is not

more than 3% smaller than the initial luminous flux.

Luminescent materials which have such a low short term

decrease result in lamps having a very high luminous flux,

also with very high wall loads.

In lamps according to the invention an electric field

strength of 150 to 1000 V/m is preferably maintained in the

column discharge during operation. This relatively high

field strength can be obtained by using an envelope having

a relatively small diameter. With a relatively low lamp

current, compact, highly loaded lamps having a high

luminous flux are then obtained."

10. The specification continues with descriptions of a number of embodiments, and with tables showing results of measurements of electronegativity and short term decrease of particular substances, and other experimental measurements. The claims follow. I set out claim one:

"A low-pressure mercury vapour discharge lamp having a

vacuum-tight, radiation-permeable envelope bearing a

luminescent layer and containing a gas filling comprising

mercury and a rare gas, and means for maintaining a column

discharge in the gas filling, the power consumed during

operation by the column discharge being at least 500 W/m2

surface area of the luminescent layer, wherein the

luminescent layer contains a luminescent material which has

the property of having at 254 nm-excitation a luminous flux

which, after the material has been subjected for 15 minutes

to ultraviolet radiation consisting substantially of the

wavelengths 185 and 254 nm, having a radiation density

between 150 and 500 W/m2 and having a ratio of 185 nm power

to 254 nm power between 0.20 and 0.40, is not more than 5%

lower than the initial luminous flux of the material at 254

nm excitation and measured under identical circumstances,

and wherein the combination of cations (as hereinbefore

defined) in the luminescent material has an

electronegativity of not more than 1.4."

11. Central to the argument whether this specification concerns a proper subject of letters patent are the two cases which I have already cited, Microcell and National Research Development Corporation. The alleged invention in Microcell, as appeared from the specification, was for a tubular self-propelled rocket projector made of reinforced plastic. Both a tubular self-propelled rocket projector and the particular plastic material were well known; but the plastic material had not previously been used in the making of such a projector, although it had been used in the manufacture of a wide variety of articles. The specification accordingly made no suggestion of novelty in relation to the article to be manufactured or the material to be used. Some evidence suggesting the prior existence of a misconception about the suitability of plastic was regarded by the High Court as of no weight since the truth was also known,

"and the specification contains not the slightest hint or

suggestion that the use of reinforced plastic for rocket

projectors has been made possible by the discovery of some

'hitherto unknown or unsuspected property of the material'.

We have in truth nothing but a claim for the use of a known

material in the manufacture of known articles for the

purpose of which its known properties make that material

suitable. A claim for nothing more than that cannot be

subject matter for a patent, and the position cannot be

affected either by the fact that nobody thought of doing

the thing before, or by the fact that, when somebody did

think of doing it, it was found to be a good thing to do."

(The facts of the case as I have stated them, and this passage, appear at pp 250-251 of the report.)

12. The judgment of Dixon CJ, McTiernan, Fullagar, Taylor and Windeyer JJ in Microcell contains a number of passages which support, or state in different terms, the proposition I have quoted. The court cited (at 248) a statement of Morton J in which the expression is used "the matter claimed is merely the use of a known material". The court also cited (at 247) a statement by Sir Stanley Buckmaster S.-G. (as he then was)

"that the mere discovery of a new use of a particular known

product is not what is meant by invention within the

meaning of the Patents Acts ... I can nowhere find any case

that throws doubt on the proposition that where by the

alleged invention no new product is obtained, no new method

of manufacture suggested nor an old one improved, the

discovery cannot be protected by a grant of Letters Patent."

The judgment comments on these statements (at 249) as follows:

"In the first passage quoted above from the judgment of

Morton J emphasis must, of course, be placed on the word

'merely', as it must be placed on the word 'mere' in Lord

Buckmaster's statement of the principle. Many valid

patents are for new uses of old things. But it is not an

inventive idea for which a monopoly can be claimed to take

a substance which is known and used for the making of

various articles, and make out of it an article for which

its known properties make it suitable, although it has not

in fact been used to make that article before."

13. National Research Development Corporation concerned a method of weed eradication to deal with the problem of weeds growing in a crop, in the manner of the scriptural tares in the wheat, so that spraying with weedicide would generally kill the crop as well as the weeds. Invention lay in the observation of the practical significance of the fact that some common weeds have an enzyme system which will break down certain otherwise inactive acids into the weedicide acetic acid. The enzyme systems of the crops to be benefited by the invention had no such effect, so that the inactive acid, when sprayed on them, remained inactive, while it was converted in the weeds into acetic acid which killed them. A patent was refused on the ground that the substances in question were known and that "the use of a known substance is not an invention", and further on the ground that "a method or use of a substance not resulting in a vendible product cannot be an invention" (at 255). Aickin QC (as he then was) submitted (at 254-255):

"These are the two half-truths which have confused the issue

for many years. The first is a complete misconception and

is quite inconsistent with the authorities which show that

a patent may be granted for the use of a known substance

where there is a novel and non-analogous mode of use, as

opposed to mere novelty of purpose".

"The initial discovery in this case is that certain weeds do,

and certain valuable crops do not, have an enzyme system

such as brings about this inter-action; the useful

application is the carrying out of selective weed control

in crops of that kind affected by weeds of that kind. The

invention lies in observing the practical significance of

the initial discovery ... . ... The whole object of the

invention is to take advantage of the discovery; that it is

a simple step to do so does not mean that there is no step."

14. The judgment of the Court (Dixon CJ, Kitto and Windeyer JJ) refers (at 262) to the proposition discussed in Microcell, that a claim

"may be seen from the specification, considered as a whole,

to be 'outside the whole scope of what is known as

invention' because, in the words of Lord Buckmaster, when

Solicitor-General, in Re B.A.'s Application (1915) 32

RPC 348 it is 'nothing but a claim for a new use of an

old substance'".

"But, as the Microcell case emphasizes, it must always be

remembered how much is wrapped up in the 'nothing but'.

Lord Buckmaster did not use the words without explanation:-

'... when once a substance is known,' he said, 'its methods

of production ascertained, its characteristics and its

constituents well defined, you cannot patent the use of

that for a purpose which was hitherto unknown' (1915) 32

RPC, at p 349. And why? Because in the postulated

state of knowledge the new purpose is no more than

analogous to the purposes for which the utility of the

substance is already known, and therefore your suggestion

of the new purpose lacks the quality of inventiveness: see

per Bowen LJ in Elias v. Grovesend Tinplate Co. (1890) 7

RPC 455, at p 468. Unless invention is found in some

new method of using the material or some new adaptation of

it so as to serve the new purpose, no valid patent can be

granted: see Moser v. Marsden (1893) 10 RPC 350, at p

358; Pirrie v. York Street Flax Spinning Co., Ltd. (1894)

11 RPC 429, at p 452. If, however, the new use that is

proposed consists in taking advantage of a hitherto unknown

or unsuspected property of the material, the situation is

not that to which Lord Buckmaster's language refers. In

that case there may be invention in the suggestion that the

substance may be used to serve the new purpose; and then,

provided that a practical method of so using it is

disclosed and that the process comes within the concept of

patent law ultimately traceable to the use in the Statute

of Monopolies of the words 'manner of manufacture,' all the

elements of a patentable invention are present: see the

Microcell Case. It is not necessary that in addition the

proposed method should itself be novel or involve any

inventive step: Hickton's Patent Syndicate v. Patents and

Machine Improvements Co. Ltd. (1909) 26 RPC 339."

15. Their Honours continued (at 263) by referring to a statement of Lindley LJ

"that the discovery how to use a known thing for a new

purpose will be a patentable invention if there is novelty

in the mode of using it as distinguished from novelty of

purpose, or if any new modification of the thing or any new

appliance is necessary for using it for its new purpose,

and if such mode of user, or modification, or appliance

involves any appreciable merit."

"But the whole passage is directed to the case of a thing

which is known - not only the existence of which is known

as a scientific fact, but the characteristics and

properties of which are understood, so that the

'appreciable merit' (1892) 3 Ch., at p 429; (1892) 9

RPC, at p 416 which is requisite for a patentable

invention must be found, if it is to be found at all,

exclusively in something which the alleged invention has

superadded to the existing knowledge concerning the thing.

There is nothing in the judgment of Lindley LJ to justify

a denial that, in respect of a process for achieving a

useful result by the employment of a substance to produce

effects which antecedently it was not understood to be

capable of producing, the inventiveness which is essential

for a valid grant of a patent may be found in the step

which consists of suggesting the use of the thing for the

new purpose, notwithstanding that there is not novelty or

'appreciable merit' in any suggested mode of using the

thing, or any modification of the thing or of an appliance

necessary for using it for the new purpose."

"There is a clear assertion of a discovery that a useful

result can be attained by doing something which the

applicant's research has shown for the first time to be

capable of producing that result. This is not a claim

which can be put aside as a claim for a new use of an old

substance, true though it be that the chemicals themselves

were known to science before the applicant's investigations

began. It is a claim which denies that the chemicals are

old substances in the sense in which the expression has

been used in such cases as Re A.F.'s Application (1913) 31

RPC 58; Re B.A.'s Application (1915) 32 RPC 348 and

Re C.G.R.'s Application (1924) 42 RPC 320. It treats

them as substances which in the relevant sense are new,

that is to say as substances which formerly were known only

partially and, so far as weed-killing potentialities are

concerned, were unknown; ... ."

16. After summarizing the specification in some detail, the judgment proceeds (at 268):

"The purpose of going thus fully into the contents of the

specification is to show that it is out of the question to

hold that on the face of the document, properly construed,

the process the subject of the first three claims appears

as nothing but a new use of an old substance. If credit be

given to the case which is made, the process differs from

the previously-known processes of its kind in this, that it

employs substances the suggestion of which for the purpose

in hand was new, was not obvious, and was to be arrived at

only by an exercise of scientific ingenuity, based upon

knowledge and applied in experimental research. The fact

that the substances themselves were already known to man

affords no valid reason for denying that the suggestion was

inventive."

17. Having looked at Microcell and National Research Development Corporation, I can now consider what is revealed by the specification in the present case. It commences by declaring that the invention relates to a low pressure mercury vapour discharge lamp, but not an ordinary one, which would have a power consumption of about 300 watts per square metre of surface area of its luminescent layer, but a highly loaded lamp, and not just any highly loaded lamp, but one in which the power consumed is at least 500 watts per square meter of surface area of the luminescent layer. (A lamp might be described as highly loaded at 400 watts per square meter of surface area of the luminescent layer.) The specification describes how to make a lamp of this kind, which will not be significantly less efficient than the ordinary low pressure mercury vapour discharge lamp.

18. The specification does not suggest that highly loaded lamps could not have been, or had not been, made previously. It appears that the most useful embodiment of the invention, the compact lamp, had not previously been made, or not with any success. But the highly loaded lamps made previously are said to have suffered from a serious disadvantage of poor efficiency, and the fact that they did so was not in dispute in this case. Indeed, the evidence of Dr Lowke, a well qualified expert, so far as the electrical discharge side of the problem was concerned, who was called by the respondent, was to the effect that there would inevitably be in a highly loaded lamp reductions of discharge efficiency which would have to be compensated for by increasing the overall efficiency of the phosphors. He said: "(T)he only way to correct for that, that I know of, is to have a more efficient phosphor."

19. The specification claims, of the investigations which led to the invention, that it was found an efficient conversion of electric power into ultra-violet radiation was possible in a highly loaded lamp, yielding an efficiency substantially equal to that of the normal lamp. But it was also found that the share of the radiation having a wave length of 185 nm was relatively higher than in normal lamps. The specification then claims that

"(t)he invention is based on the recognition that failure of

the prior art lamps with high wall load is not due to a low

efficiency of the conversion into ultra-violet radiation,

as has been generally assumed so far, but is due to the

luminescent materials used."

The defect in the luminescent materials was not their efficiency under normal conditions, but their sensitivity to 185 nm radiation, and to attack by mercury. The specification does not claim that either of these effects was in itself not known previously, but neither of them presented the same problem for a normal lamp which it presented for a highly loaded lamp. This is because in a highly loaded lamp the 185 nm radiation forms a higher proportion of the total radiation, and in addition, the luminous layer in highly loaded lamps is exposed to a much greater number of collisions with excited mercury atoms or mercury ions than is the case in normal lamps. In the words of one of the inventors, Dr Ligthart:

"The old thinking was that it was the discharge which was

defective in lamps of small diameter such as a 10 mm lamp.

What we proved both empirically and in our modelling, was

that in fact it was not the discharge, but it was

characteristics of the phosphor itself which led to the

problem of efficient compact lamps. The discharge in a 10

mm lamp in fact performs very well. The insight that we

achieved in 1977 was that with the recognition of the right

characteristics to search for in the lamp, an efficient

discharge, albeit with a very high 185 nm content, could be

used to produce a practical and efficient compact

fluorescent lamp."

That the discharge was thought to be the problem was plainly confirmed by the respondent's witness Dr Lowke, who had worked at Westinghouse, the major United States competitor of the appellant, until the end of 1975. Dr Lowke said that, at Westinghouse, consideration was given to developing a compact fluorescent lamp, and

"my answer was that it would be hard to do because there

would be inevitable losses in efficiency due to the reasons

I described (i.e. the discharge problems) and that the only

way you could make a lamp of acceptable efficacy was to

have better phosphors and that's hard to do and would

require a lot of work over a lot of years and a lot of

experimentation ... ."

20. (There is a quite independent importance to be attached to this evidence of Dr Lowke. The appellant relied on the commercial success of the invention, which is relevant to novelty as well as to obviousness, and therefore to whether there is a manner of new manufacture (see Fox, The Canadian Law and Practice relating to Letters Patent for Inventions, 4th ed. (1969) 73 et seq., 102). But the learned trial judge, in a passage I shall quote, discounted that success as due to "the higher cost of electricity, making (the invention's) energy-efficiency more important to consumers". With respect, the observation does not meet the point. Westinghouse, as well as Philips, thought a compact lamp desirable, and they thought so in the period before the priority date, when higher energy costs had already affected the entire industrial world, and their continuance was, in actual fact, perhaps more feared than subsequent economic history has justified. Events of such notoriety are a fit subject of judicial notice, but in any case, there was evidence that "(t)he 1973 oil crisis set off unprecedented demand for energy efficient appliances, of which lighting products were an important part". That was four years before the priority date. The appellants' point - which the authorities support - is that their own success in solving a problem which was recognized by others; awaited solution for several years; and could be seen to be blocking a potentially profitable development, tends to confirm that what they achieved was an invention. The force of such an argument always depends upon showing that there was reason for others to try to do, or that others have in fact been shown to have tried to do, what only the patentee achieved. The inference is then that the invention is no mere analogous use of a well known thing, nor was the advance made an obvious one. See The General Tire and Rubber Company v. The Firestone Tyre and Rubber Company Limited (1972) RPC 457 at 503; Allsop Inc v. Bintang Ltd [1989] FCA 297; (1989) 15 IPR 686 at 702-703. Here, Dr Lowke's evidence shows Westinghouse discussed making a compact fluorescent lamp, only to accept that it could not; and the invention, when made, had the commercial success which had been anticipated for it.)

21. If obviousness had not been abandoned, there might have been a question whether it was obvious to seek to use, in a highly loaded lamp, the particular phosphors which answered the requirements as to electronegativity and short term decrease required by the patent. There were of course many phosphors, and some of those which were efficient and useful in ordinary lamps failed to meet one or other of these criteria. While ever the view prevailed that what was needed was additional efficiency, which the evidence shows was only being achieved in the order of one or two percent, the reaction at Westinghouse was perhaps to be expected. But, at all events, obviousness is not in issue, and the question is whether there is any basis on which it can be said that the invention claimed in the specification was not a manner of new manufacture within the meaning of the Act.

22. It seems to me it cannot be said that the appellants' discovery involved on its face (or, indeed, on all the evidence) merely taking phosphors which were known and used for fluorescent lamps, so as to "make out of (them) an article for which (their) known properties make (them) suitable", within the meaning of the passage I have quoted earlier from Microcell. On the contrary, the particular properties which are relevant, the short term decrease and electronegativity levels identified in the specification, although the existence of the phenomena in question was known in the same way as a host of other unimportant facts were known, were not thought to be requisite for efficient fluorescent lamps, and were not in fact requisite for such lamps if the lamps were not highly loaded. The properties which made certain phosphors suitable for use in highly loaded lamps were properties which had not been recognized as significant for that purpose, and certainly not as essential criteria. It is important, too, to note the explication of this ground of rejection of a claim for a patent, that it is nothing but a claim for a new use of an old substance, in National Research Development Corporation (at 262). The proposition is concerned with a substance the characteristics of which are well defined, the new use of which is merely analogous to the purposes for which its utility is already known. This cannot be said here, where it was previously thought that only a more efficient phosphor would be of any utility in producing an efficient highly loaded lamp, and the relevant characteristics were not thought of importance.

23. Although it might be said, as a matter of simple English, that use in a highly loaded lamp is analogous to use in an ordinary lamp, that is not the meaning which "analogous" has in patent law. An analogous use in patent law is one which presents no difficulty to be overcome, the adoption of which requires no inventive step. The example commonly given is illuminating. The first person to use stainless steel to make a sink would have applied to an analogous use (analogous to a great number of other uses to which it had already been put) a material already known to have every quality required, and he would have made an item each feature of which was already completely understood; he would have overcome no difficulty at all. Similarly, the simple transfer to the front wheels of a carriage of the type of spring already in use for the back wheels exemplified analogous purpose, and was not inventive: Morgan and Co. v. Windover and Co. (1890) 7 RPC 131.

24. But the succeeding words in the judgment of Dixon CJ, Kitto and Windeyer JJ in National Research Development Corporation (at 262), after their reference to the ground of rejection under discussion, do apply. There is here invention "found in some new method of using the material or some new adaptation of it so as to serve the new purpose". An advantage is taken of a hitherto unrecognised characteristic of the apparent severe loss of efficiency in a highly loaded lamp, namely, the much greater effect of 185 nm radiation and mercury attack upon an otherwise perfectly efficient phosphor when utilized in such a lamp, and the ability of those phosphors only which are identified in the specification to utilize such radiation and resist such attack in the new kind of lamp. Indeed, the appellants' lamp falls squarely within the language of the court in National Research Development Corporation (at 263): the specification describes

"a process for achieving a useful result by the employment of

a substance to produce effects which antecedently it was

not understood to be capable of producing, the

inventiveness which is essential for a valid grant of a

patent (being( found in the step which consists of

suggesting the use of the thing for the new purpose".

Dr Lowke's evidence clearly acknowledges the assertion in the specification that existing phosphors were not understood to be capable of producing the effect of efficient luminous flux, under the conditions present in a highly loaded lamp, which was in fact obtained by the appellants' lamp. In the words their Honours used in the same case (at 265), the specification asserts

"a discovery that a useful result can be attained by doing

something which the (appellants') research has shown for

the first time to be capable of producing that result. ...

It is a claim which denies that the (phosphors) are old

substances in the sense in which the expression has been

used in (the relevant authorities). It treats them as

substances which in the relevant sense are new, that is to

say as substances which formerly were known only partially

and, (so far as relevant potentialities to resist the

greater short term decrease effect and greater mercury

attack involved in a highly loaded lamp are concerned),

were unknown ... ."

(They were unknown in the sense that their significance was not appreciated, and therefore it had not been thought necessary to undertake any detailed examination and estimation of the relevant characteristics of the materials.)

25. The course which this appeal has taken makes it desirable to add that it is only in the clearest of cases that the question of analogous use can properly arise under s. 18(1)(a). I have already explained how I understand that provision. Unless on the face of the specification the question arises, it seems to me that analogous use must be raised, if at all, under the ground of obviousness (which has here been abandoned). Both Terrell (op cit) and Blanco White (op cit) treat analogous use under the heading of obviousness, the former in para. 5.113, and the latter in para. 4-216 (and see secs. 4-906 and 4-907). When it is recognized that the point is in its nature an obviousness point, its difficulties in this case, on the most favourable view of the evidence for the respondent, must be increased by the argument from the compact fluorescent lamp's commercial success.

26. The trial judge noted the concession of counsel for the respondent that the short term decrease and electronegativity figures "were not already well-known parameters of a useful phosphor"; but he said she submitted the case was

"nothing more than a claim for the use of a known material (a

phosphor) in the manufacture of known articles (low-pressure

mercury vapour discharge lamps) for the purpose for which its

known properties (luminescence) make that material suitable".

He recorded that, in making that submission, she conceded

"that the realization that the problem about compact lamps

lay, not in the efficiency of their conversion of

electrical energy into ultra-violet radiation, but in the

efficiency of the phosphor, may have been a break-through

in the development of compact lamps. But she says that

this discovery was not patentable."

With respect, his Honour does not seem to have noticed that the last concession contained a serious error. The break-through was not at all in realizing that the problem lay in the efficiency of the phosphor. Some very efficient phosphors, according to the evidence, were quite unsuitable for use in compact lamps. The break-through was in realizing that the efficiency of an efficient phosphor would be destroyed in the environment of a highly loaded lamp, if its short term decrease or its electronegativity characteristics were other than those identified by the patentee. But even more importantly, counsel's argument was a classical example of a faulty syllogism. All compact low pressure mercury vapour discharge lamps are low pressure mercury vapour discharge lamps, but not all low pressure mercury vapour discharge lamps are compact lamps. The known property of luminescence made a number of phosphors suitable in normal low pressure mercury vapour discharge lamps, but it did not follow that the same property made them all suitable in a compact lamp, and in fact those which did not fulfil the criteria specified in the patent were quite unsuitable.

27. The ground on which his Honour decided that the patent did not relate to a manner of new manufacture is to be found in the following passages from his reasons:

"I think everyone would agree that, if a person discovered a

new property in a known material which, for the first time,

made it apparent that the material was suitable for a new

use, the discovery would amount to an invention and the

claim of the patent would be for a manner of new

manufacture. But that is not this case. The present

patent does not claim the discovery by the patentees of any

new property of phosphors, making them suitable for use in

highly loaded low-pressure mercury vapour discharge lamps.

The luminescent qualities of phosphors had long been known.

. . .

The contribution to the art claimed by the patentees -

in relation to Claims 1 to 5, the only contribution they

claim - is to specify desirable STD and e.n limits for

phosphors used in highly loaded lamps. They make no claim

that a phosphor whose STD or e.n exceeds one or both of

those limits will be unsuitable for use in a highly-loaded

lamp; it is just that the lamp will be less efficient than

a conventional fluorescent lamp and, presumably, less

competitive with incandescent lamps. Neither the patent

nor the evidence suggests that the STD and e.n values

stipulated in the patent reflect any discovery or new

scientific insight by the patentees; rather they were

figures chosen to reflect the patentees' judgment as to the

degree of efficiency-loss from these two causes which would

be commercially acceptable. No doubt the choices were

carefully calculated, and I do not doubt that phosphors

meeting those parameters have enabled Philips to market a

successful product; but the stipulated figures are

arbitrary, in the non-pejorative sense of depending upon

the will or discretion of the patentees.

During the course of their oral submissions, counsel

for the applicants described Claim 1 as 'a statement of the

criteria to be met by manufacturers to achieve a vendible

product. The patent tells people how to make the lamp.

They know about phosphors but this tells them in two

important respects'; that is, STD and e.n. In support of

that position, counsel pointed to evidence establishing

that, since the priority date, compact highly-loaded lamps

have begun to be manufactured and, especially in recent

years, have sold in significant numbers.

There is no doubt about the increasing use of compact

highly-loaded lamps. There is some dispute as to its

cause. There is evidence that a major factor in the

growing popularity of compact lamps is the higher cost of

electricity, making their energy-efficiency more important

to purchasers. But, be that as it may and accepting the

success of the Philips product, it seems to me that it is

not an invention, or a manner of new manufacture, for

someone to specify the criteria required to be met, in the

manufacture of a known product from known materials, in

order to achieve vendibility. As was said by Dixon CJ,

Kitto and Windeyer JJ in National Research Development

Corporation v Commissioner of Patents [1959] HCA 67; (1959) 102 CLR 252 at

262: 'Unless invention is found in some new method of using

the material or some new adaptation of it so as to serve

the new purpose, no valid patent can be granted'."

28. In my respectful opinion the statement that "(t)he luminescent qualities of phosphors had long been known" is irrelevant. The patentee did not claim the discovery of these luminescent qualities. What was claimed was that the inefficient use of these qualities in highly loaded lamps in accordance with the prior art, so inefficient that compact lamps were not made and other highly loaded lamps were only made for use in circumstances where inefficiency could be accepted, was attributable to factors quite different from that previously thought responsible, and was remediable by the utilization of characteristics of some phosphors which had not previously been recognized as important for the purpose, so that no appropriate selection had been made. This discovery his Honour, elsewhere in his judgment, acknowledged to have been "truly inventive", but he said that no patent had been granted in respect of it. However, no patent could have been granted in respect of the mere discovery. The discovery of a phenomenon of nature is not a fit subject for a patent: Gottschalk, Acting Commissioner of Patents v. Benson [1972] USSC 223; 409 US 63 (1972); International Business Machines Corporation v. Commissioner of Patents [1991] FCA 625; (1991) 22 IPR 417 at 419, 423, 425; Arrhythmia Research Technology Inc. v. Corazonix Corp. 22 USPQ 2d 1033 (1992) at 1035; Goldsmith, Patents of Invention (1981) 54; Terrell op cit secs. 2.05, 2.06. The specification claims a patent for the true subject of a patent, the practical application of the discovery in the production of a vendible product. As National Research Development Corporation and other authorities show, the patent would still be good if construed as for a method of application of the discovery in order to achieve a result falling within the concept of a manner of new manufacture, but the mere discovery of the scientific explanation for the failure of the prior art was not patentable.

29. However, the claim made by the specification is not limited to the delineation of desirable short term decrease and electronegativity limits, and it is simply not correct to suggest that the patentee "make(s) no claim that a phosphor whose STD or e.n exceeds one or both of those limits will be unsuitable for use in a highly loaded lamp". The specification directly states, as to short term decrease, a finding "that for a higher value of this decrease lamps are obtained which furnish an unacceptably low luminous flux after having burned for the few minutes which are required for obtaining a steadily burning lamp"; and as to electronegativity, a finding

"that the cation of a luminescent material suitable for lamps

according to the invention must have a relatively low e.n.,

namely not more than 1.4. ... (F)or example, ... a

luminescent material containing zinc (e.n equals 1.6) as a

cation, which in normal lamps shows some mercury attack

only after a relatively long operating period, can

definitely not be used in highly-loaded lamps because the

luminescent layer is already markedly darkened after the

lamp has burnt for a period of from some minutes to some

hours." (Emphases added.)

Indeed, the respondent's expert, Dr Lowke, in a passage I have quoted, plainly acknowledged that, in accordance with the prior art, Westinghouse could not make a compact luminescent lamp "of acceptable efficacy".

30. The essence of the invention, as described in the specification, is to provide an efficient highly loaded lamp where previously none was thought possible without the development of phosphors of sufficiently greater efficiency to make up for the losses believed to be inevitable in such a lamp and, in the most important commercial application of the invention, to provide a compact lamp where none at all existed before. It is inadequate to the point of error to describe this as merely the specification of desirable short term decrease and electronegativity limits for phosphors used in highly loaded lamps. What the patentee has done falls precisely within the often-cited words of Lindley LJ which Lord Morton of Henryton, in a speech that commanded the unanimous assent of the House of Lords, adopted in Benmax v. Austin Motor Company Ld. (1955) 72 RPC 39 at 45:

"(A) patent for a new use of a known contrivance is good and

can be supported if the new use involves practical

difficulties which the patentee has been the first to see

and overcome by some ingenuity of his own".

31. On the question of construction of the words "contains a luminescent material", in claim one, I have already said that I agree in the conclusion reached by Lockhart J. However, I desire to add something about the question of the use of the body of the specification as a context for the understanding of an expression in a claim. In argument in the present appeal, it was suggested that the expression under consideration must be understood as it appears in the claim, without reference to the other parts of the specification. Authorities were cited containing statements such as the proposition which Lord Evershed MR, in Rosedale Associated Manufacturers Ld. v. Carlton Tyre Saving Coy. Ld. (1960) RPC 59 at 69, drew from the speech of Lord Russell of Killowen in Electric and Musical Industries Ld. v. Lissen Ld. (1938) 56 RPC 23, when he said:

"It is no doubt true and has been well established ... that

you must construe the claims according to their terms upon

ordinary principles, and that it is not legitimate to

confine the scope of the claims by reference to some

limitation which may be found in the body of the

specification but is not expressly or by proper inference

reproduced in the claims themselves. On the other hand, it

is clearly no less legitimate and appropriate in

approaching the construction of the claims to read the

specification as a whole. Thereby the necessary background

is obtained and in some cases the meaning of the words used

in the claims may be affected or defined by what is said in

the body of the specification."

Such statements give only qualified support to the idea that the reader's attention should be confined to the four walls of the claim itself. They do, however, emphasize a consequence of the special function of a claim as a statement defining the monopoly claimed.

32. It is of course important, when construing any document, to take account of the particular nature of the document in question, which may provide reasons for preferring one approach to construction over another. A claim in a specification does have a special nature, one consequence of which bases the submission. At the same time, one should not lose sight of the considerations favouring a beneficial construction discussed by Taylor J in Martin v. Scribal Pty Ltd [1954] HCA 48; (1954) 92 CLR 17 at 97, 102-103, and mentioned in the other authorities cited in Elconnex Pty Limited v. Gerard Industries Pty Limited [1991] FCA 567; (1991) 32 FCR 491 at 512-514.

33. Although, in patent law, the rules of construction of documents are applied to a distinctive category of document, with very special characteristics, which may influence the result of their application, the rules of construction themselves do not change because they are applied to specifications or claims. Those rules relate to the use of language, and to the laws of thought and its expression, which have the same general application in patent law as in other areas of the law. While suggestions have been made that an unambiguous statement in a part of a document, such as a claim, may preclude resort to a wider context, the modern view is that whether a statement is unambiguous should only be decided after the context has been taken into account. Mason J stated this principle in his dissenting judgment in K and S Lake City Freighters Proprietary Limited v. Gordon and Gotch Limited [1985] HCA 48; (1985) 157 CLR 309 at 315:

"Problems of legal interpretation are not solved

satisfactorily by ritual incantations which emphasize the

clarity of meaning which words have when viewed in

isolation, divorced from their context. The modern

approach to interpretation insists that the context be

considered in the first instance, especially in the case of

general words, and not merely at some later stage when

ambiguity might be thought to arise."

In Short v. F.W. Hercus Pty Ltd [1993] FCA 51; (1993) 46 IR 128 at 134-136, in a judgment with which Drummond J (at 138 and 139) expressed his agreement, I discussed the width of the context of which account may be taken in the construction of a document, and cited this passage as being "a broad proposition, applicable to problems of construction generally, although it was put forward in the context of statutory interpretation." In my opinion, there is no special exception which makes it inapplicable to the construction of a claim in a specification. In particular, it is not excluded by the accepted rules stated by Sheppard J in Decor Corporation Pty Ltd v. Dart Industries Inc (1988) 13 IPR 385 at 400. See also Blanco White, op cit para. 2-101 et seq.

34. When the context of the specification as a whole is considered, as well as the wider context of the established practice of the industry of using mixtures of phosphors (which must be taken into account if the claim is to be construed, "not as a matter of abstract uninformed construction", but making "a common-sense assessment" of what it would convey to the skilled reader: see Populin v. H B Nominees Pty Ltd [1982] FCA 45; (1982) 41 ALR 471 at 476; Allsop Inc v. Bintang Ltd (supra, at 693)), there can be no doubt of the meaning of the claim. Indeed, in that light, the construction for which the respondent contends can be seen to be one "which leads to an absurd result": Henriksen v. Tallon Limited (1965) RPC 434 at 443, per Lord Reid; and see Rescare Ltd v. Anaesthetic Supplies Pty Ltd (1992) 25 IPR 119 at 143.

35. Finally, with respect to novelty, as I have indicated, I am in agreement with what Lockhart J has written. However, I shall add some discussion of my own.

36. The anticipation pressed upon the Court, in argument on behalf of the respondent, is documentary. It is not suggested that an efficient highly loaded lamp, as described in the specification, had been made as at the priority date. But the respondent relies on certain papers, published in scientific journals, relating to the then quite newly discovered three phosphors, YOX, BAM and CAT. In the course of the articles, comments were made such as that in a paper presented at New Orleans in July 1974 by J.M.P.J. Verstegen, D. Radielovic and L.E. Vrenken: "An advantage of the rare earth-activated phosphors is their high efficiency at elevated temperatures. This makes them suitable for high-loaded lamps in which the Hg pressure is amalgam-regulated." (Hg of course refers to mercury.) Another paper, presented by L.E. Vrenken at a conference in 1976, discusses the use of these phosphors in luminaires. (A luminaire is an enclosed fitting containing a lamp.) The paper includes a table setting out various lamp types, which does not suggest that compact lamps were in mind; but it does contain the statement:

"The use of the new phosphors is not restricted to 40W T 12

lamps. An advantage of the rare earth activated phosphors

is their high efficiency at elevated temperatures, which

makes them suitable for those situations where the bulb

wall temperature is relatively high, e.g. with normal lamps

enclosed in luminaires or with highly loaded lamps."

37. The first thing which should be said about these papers is that the law requires them to be construed on the basis of their meaning at the date when they were written: Blanco White op cit para. 4-105. It will be noticed that their language does not suggest the contemplation of a then future development of some new lamp type. On the contrary, in the course of papers directed to other subjects, they make the comment that certain phosphors are suitable in certain apparently known situations involving elevated temperatures. In each case, the reference to highly loaded lamps is a reference to an example of such a situation, as is also the reference to the use of luminaires. The papers are simply not directed to the development of a new type of efficient highly loaded lamp.

38. The point I have been making is sufficient in itself to demonstrate that the papers do not reveal "the same information as is given by the later patent so far as it relates to the particular claim concerned" (Blanco White op cit para. 4-105), as is requisite to establish an anticipation. The papers neither suggest that an entirely new type of lamp is possible, which would overcome the discharge problem believed to exist, nor contain any directions for the making of such a lamp.

39. But the matter does not end there. At the times, before the priority date, when these papers were written, the references to temperature would have directed attention away from the problem later dealt with by the invention. Amalgam regulation had nothing to do with high loading, as that concept is understood in the specification: amalgam regulation was concerned with the problem of high temperature, encountered particularly in a closed luminaire, which leads to too high a mercury pressure, affecting luminous efficacy. With an amalgam regulated lamp the pressure is reduced by, for example, the application of indium amalgam. In this context, Dr Lowke made it clear that he did not understand the Vrenken paper as intending to mention the possibility of new lamps, although he contended a person alert to new possibilities would, on reading the paper, think the particular phosphors were prime candidates for other possible applications where lamps would be highly loaded. That, of course, is not a denial of novelty, but an argument directed to obviousness.

40. Furthermore, and this is a perfectly natural consequence of the fact that the papers are not concerned with the present problem, there is no reference in them to any definition of what is meant by "highly loaded". The evidence shows that, before the priority date, lamps could be referred to as highly loaded, the wall loading of which was 400 watts per square meter of the luminescent layer, that is to say, lamps which would not be highly loaded lamps within the meaning of the patent. It follows that the language of the papers is perfectly consistent with them referring to lamps not covered by the specification. Dr Lowke conceded that he would not have known in 1977, from the information in the papers, whether the new phosphors in question would have worked in a compact lamp which consumed power in excess of 500 watts per square meter, that is, a highly loaded lamp within the meaning of the specification.

41. For these reasons, as well as those given by Lockhart J, I think the respondent did not make out its case on the ground of novelty.

42. In my opinion, the appeal should be allowed with costs; the orders made at first instance should be set aside; and the appellants should be directed to bring in, on a date to be fixed, orders in accordance with the reasons of this Court, to be made in lieu of the orders made at first instance.