CCOM Pty Ltd v Jiejing Pty Ltd

I certify that this and the preceding three (3) pages are a true copy of the Reasons for Judgment herein of the Honourable Justice Burchett

On appeal from a Judge of the Federal Court of Australia

JUDGES: BURCHETT, CARR & GOLDBERG JJ DATE: 23 October 1998 PLACE: MELBOURNE

REASONS FOR JUDGMENT CARR and GOLDBERG JJ: INTRODUCTION In this matter RGC Mineral Sands Ltd ("RGC"), the respondent at first instance, applies for leave to appeal and, subject to the grant of such leave, seeks to appeal from part of orders made by a judge of the Court in proceedings for infringement of patent brought by Wimmera Industrial Minerals Pty Limited ("Wimmera"), the applicant at first instance. In the abovementioned orders, the learned trial judge, on Wimmera's application, directed the amendment of Wimmera's patent in the terms sought in a notice of motion filed in the course of the infringement proceedings. The infringement proceedings were initially based on a petty patent granted to Wimmera and published on 2 June 1994. However, by amendments to the pleadings, the proceedings have focussed on a standard patent granted to Wimmera on 11 May 1994. That standard patent (Australian Letters Patent No. 639,089 of which Wimmera is the registered proprietor) is for an invention entitled "Production of Synthetic Rutile" ("the Patent"). At this stage it is sufficient to summarise the invention briefly in terms which draw fairly heavily on the learned primary judge's own description. The invention provides a process for producing synthetic rutile from a titaniferous ore, in three basic steps. The first is a reduction step whereby the iron content of the ore is partially converted to metal by gaseous or carbothermic reduction. In the second step the product of the first step is subjected to an aqueous treatment which results either in the dissolution of the metallic iron content of the mineral or in the conversion of the metallic iron to a separable iron oxide product. In the third step the titaniferous product of the second step is subjected to a leaching treatment for at least partial removal of residual iron, magnesium, manganese and aluminium. The titaniferous product of that leaching will have a particularly high titanium content and may be used in place of natural rutile or other materials with a high titanium content. By its amended defence and cross‑claim RGC contends that both the petty patent and the Patent are wholly invalid and seeks an order that they be revoked. Wimmera filed its specification for the Patent on 1 March 1991. The specification as filed was altered in a number of respects before acceptance by the Patents Office on 15 July 1993. In his reasons for judgment, the learned primary judge described in detail the specification as filed and summarised the material differences between that document and the specification as accepted. His Honour then set out the amendments sought by Wimmera in its amended notice of motion. Annexed to these reasons are three schedules, namely Schedule A, Schedule B and Schedule C. The content of those schedules comes almost entirely from his Honour's reasons. Schedule A is a description of the specification as filed, starting with the description of the prior art. Schedule B is his Honour's summary of the material differences between the specification as filed and the specification as accepted. The specification as accepted is how it stood when Wimmera's motion was heard at first instance. Schedule C is a description of the amendments for which Wimmera applied and which his Honour directed to be made. His Honour made orders which in effect allowed all of the amendments sought by the respondent. In summary, his Honour rejected RGC's contentions that as a result of the amendments: . the specification would claim matter not in substance disclosed in the specification as filed - s 102(1) of the Patents Act 1990 ("the Act"); . certain of the claims would not in substance fall within the scope of the claims of the specification before amendment - s 102(2)(a) of the Act; and

. certain of the claims would not be clear and succinct and fairly based on the matter described in the specification - s 102(2)(b) when read with s 40(3) of the Act. Only the first of the above issues remained live in the appeal. Furthermore, as will be seen below, the appellant's challenge is confined to so much of the amendments allowed as would permit two additional claims ("additional claims 4 and 5"). RGC had, at first instance, also advanced various matters by reason of which it contended that the learned primary judge should exercise his discretion against ordering the amendments. His Honour rejected those contentions. The appellant does not appeal against the discretionary aspects of his Honour's judgment. THE STATUTORY REGIME Section 105(1) of the Act empowers the Court in any "relevant proceedings" in relation to a patent, on the application of the patentee, to direct the amendment of a patent. "Relevant proceedings" in relation to a patent means court proceedings for infringement or for revocation of a patent or in which the validity of the patent, or of a claim, is in dispute - see the definition in Schedule 1 to the Act. Section 105(4) provides that an amendment is not to be directed which is not allowable under s 102. Section 102 relevantly provides as follows: "(1) An amendment of a complete specification is not allowable if, as a result of the amendment, the specification would claim matter not in substance disclosed in the specification as filed. (2) An amendment of a complete specification is not allowable after the specification has been accepted if, as a result of the amendment: (a) a claim of the specification would not in substance fall within the scope of the claims of the specification before amendment; or (b) the specification would not comply with subsection 40(2) or (3). (3) This section does not apply to an amendment for the purpose of correcting a clerical error or an obvious mistake made in, or in relation to, a complete specification." Section 40(2) of the Act requires that a complete specification describe the invention fully, including the best method known to the applicant of performing the invention, and end with a claim or claims defining the invention. Section 40(3) requires the claim or claims to be clear and succinct and fairly based on the matter described in the specification. LEAVE TO APPEAL There does not appear to be any authority squarely in point on the question whether an order made under s 105(1) of the Act is interlocutory or final. Mr D K Catterns QC, who with Mr A J Ryan appeared as senior counsel for Wimmera, told us that they had not found any authority on that particular point. None was otherwise cited to us. In deference to counsel, we have not searched for any such authority. We treat the matter as being a case of first impression but, of course, one which is to be decided by applying the principles explained in the leading cases such as Licul v Corney (1976) 8 ALR 437 at 446; Carr v Finance Corporation of Australia Ltd [No 1] (1981) 147 CLR 246 at 248 and Computer Edge Pty Ltd v Apple Computer Inc. (1984) 54 ALR 767 at 768. We think that we are constrained by those authorities to hold that the orders made at first instance in this matter were interlocutory. They cannot be said finally to have determined, in a legal sense, all the rights of the parties that were in issue in these proceedings. If we were not so constrained, we would have been inclined to hold that the orders were relevantly final. The orders which RGC seeks to challenge were granted as a result of a motion, notice of which was filed within the proceedings that comprise the original application. But to characterise the challenged orders as interlocutory rather than final, so it seems to us, is to attach too much importance to form over substance. The true characterisation of what happened is that Wimmera has successfully invoked the Court's jurisdiction and power to direct amendment of the Patent, over the objections of RGC. The consequence of that is that the Patent will be amended once a copy of the order is filed at the Patent Office - see s 105(6). Wimmera's right to amend its patent has been finally determined by the orders made. That is a valuable right, conferred by the Act in relation to a public document. An example of the importance and value of that statutory right can be seen, in the context of the United Kingdom statutory equivalent, in May & Baker Ltd v Boots Pure Drug Co Ltd (1948) 65 RPC 255; (1948) 66 RPC 8; (1950) RPC 23. The appeals in that case, to the Court of Appeal and eventually to the House of Lords were not against the judgment that the patent was bad and had to be revoked, but were against the refusal of leave to amend. In any event, we consider that leave to appeal should be granted because important matters of public law are involved, in an area where it cannot be said that the law has been clearly settled. We think that this case thus raises "special considerations" - see Decor Corporation Pty Ltd v Dart Industries Inc (1991) 33 FCR 397 at 399. THE APPEAL As mentioned above, the appeal was confined to so much of his Honour's decision as granted Wimmera leave to amend its patent by adding additional claims 4 and 5. Those claims read as follows: "4. A process according to any one of the preceding claims further comprising mixing an additive into the titaniferous ore or concentrate to encourage the formation of the separate minor impurity bearing titaniferous phase in the reduced product of step (i). 5. A process according to claim 4 wherein the additive is an oxide or oxides." It was common ground that additional claim 5 stood or fell with additional claim 4, so attention may be confined to additional claim 4. The complete specification, incorporating the amendments made before acceptance, contains the following: "Accordingly, the present invention provides a process for upgrading the titania content of a titaniferous ore or concentrate which process comprises the steps of: (i) reducing the titaniferous ore or concentrate using a solid carbonaceous reductant under temperature conditions which promote the formation of metallic iron, a major rutile phase, and a separate minor impurity bearing titaniferous phase to produce a reduced product; (ii) . . ." In the body of the specification as filed there were contained a number of optional additional steps which could be incorporated in the process. The second of those additional steps ("the additive option") was described in the following terms: "2 Additives, such as chlorides or oxides (eg. Mn O2)may be mixed into the titaniferous mineral prior to reduction in order to redistribute the metallic iron produced via segregation reactions, thereby influencing metallic iron removal, or to encourage the formation of an acid leachable minor impurity bearing phase." The learned primary judge found that the verbal difference between the proposed claim 4 and the specification as filed did not result from the proposed amendment. This was, so his Honour reasoned, because as a matter of construction of the specification as it then stood, the phrase in the additive option "minor impurity bearing phase" meant the minor impurity bearing titaniferous phase. Step (i) in the consistory clause spoke of reducing the titaniferous ore under temperature conditions which promote the formation of, inter alia, a separate minor impurity bearing titaniferous phase. The description of step (i) in the body of the specification, so his Honour found, disclosed that the various impurities are predominantly concentrated into a small amount of a separate titaniferous phase. Step (i) of claim 1 repeated the phrase in the consistory clause - "separate minor impurity-bearing titaniferous phase". His Honour noted that any additive was to be mixed into the titaniferous mineral prior to reduction. In those circumstances, his Honour held that the reference in the additive option to a "minor impurity-bearing phase" must be to a minor impurity-bearing titaniferous phase, because that was the result, elsewhere described in the document, of the reduction process. The amendment converted an optional feature of the invention into an essential one. However, as that optional feature was in substance disclosed by the specification, the amendment was unobjectionable, as had been held in AMP Incorporated v Hellerman [1962] RPC 55. WHETHER THE PRIMARY JUDGE MISCONSTRUED S 102(1) OF THE ACT? RGC accepted, subject to a proviso, the approach which his Honour held that s 102(1) required, i.e. a comparison between: . "the matter" which "the specification would claim", "as a result of the amendment" (on RGC's case, the whole of additional claims 4 and 5, respectively); and . "the matter", disclosed "in the specification as filed". In particular, again subject to the same proviso, RGC agreed that the first stage is to identify "the matter resulting from the amendment", the phrase used by his Honour. In that stage, as his Honour observed, the "specification as it stands" is compared with "how it would stand after amendment". The proviso for which RGC contended is that his Honour's phrase "the matter resulting from the amendment", in s 102(1) should be understood as meaning "the matter claimed as a result of the amendment" (emphasis added). RGC contended that the result of the first stage must be relevantly to identify additional claims 4 and 5 as matter claimed as a result of the amendment. It submitted that those claims had no equivalent in the specification as filed. RGC acknowledged that those claims were dependent on existing claims. RGC contended that his Honour had undertaken an incorrect comparison between additional claim 4 and the specification as it stood (i.e. as amended between filing and acceptance) including the consistory clause as it had been amended and step (i) of claim 1 as so amended. On behalf of RGC it was submitted that nowhere in the specification as filed was the phrase or concept of a "minor impurity bearing titaniferous phase" mentioned or discussed or, critically, described as a feature of the invention. The introduction, in additional claim 4, of the concept of the use of an additive to "encourage the formation of" a "minor impurity bearing titaniferous phase" therefore, so it was contended, offended s 102(1). This was because it claimed matter not in substance disclosed in the specification as filed. The presence of the word titaniferous in claim 1 and the consistory clause as amended was, so RGC submitted, irrelevant. We do not accept the submissions thus advanced on behalf of RGC. The suggested proviso, subtle as it is, in our opinion, puts an unnecessary gloss on s 102(1). That subsection requires one first to identify precisely what is the amendment. In this case that is done by identifying the difference between the specification as accepted (and as it stood at the hearing of the motion at first instance) on the one hand and, on the other hand, as the specification would read if amended in the manner sought. Then one reads the specification as a whole (as so amended in the manner sought) to see whether as a result of the amendments sought (which must mean by reason of the amendment sought) the specification would claim matter not in substance disclosed in the specification as filed. The subsection focuses on the amendment proposed and it must be that amendment which has the result of pushing the claimed matter over the line defined by the expression "matter not in substance disclosed in the specification as filed." The key point to keep in mind is, as counsel for the respondent contended (in our view correctly), that the words "as a result of the amendment" are not to be confused with the expression "after the amendment". RGC complained that the primary judge compared what was then the proposed new claim 4, not with the specification as filed, but as it then stood. Counsel for RGC took us to page 19 of the primary judge's reasons, where his Honour referred to: (a) the description of step (i) in the body of the specification as it then stood; and (b) step (i) of claim 1; as each containing the words "separate minor impurity bearing titaniferous phase", whereas in fact the specification as filed did not contain that phrase. But his Honour can be seen to have done this only as part of the process of identifying the precise nature of the proposed amendment - what was it that was to be changed? This may be described as the "first stage". The first stage, which requires a comparison between the specification as it stands and how it would stand after amendment, enables the identification of what matter results from the amendment. It is only after one determines what matter results from the amendment that one turns to a consideration of, or comparison with, the specification as filed. Optional step 2 - the additive option - did not, in the specification as filed describe the "minor impurity bearing phase" as a "minor impurity bearing titaniferous phase". However, when identifying the matter resulting from the amendment, the description of the additive option in the specification as filed had to be construed by reference to: . the expression "a separate minor impurity bearing titaniferous phase" in step (i) of the consistory clause of the specification as it stood; . the description of step (i) in the body of the specification as it stood as disclosing that the various impurities are predominantly concentrated into "a small amount of a separate titaniferous phase"; . step (i) of claim 1 in the specification as it stood which repeated the phrase "a separate minor impurity bearing titaniferous phase"; and . the fact that any additive is to be mixed into the titaniferous material prior to reduction. So construed, the additive option in the specification as filed, while not expressed in terms of an acid leachable minor impurity bearing titaniferous phase must be taken as having that meaning. RGC submitted that the claim in claim 4 in relation to the separate minor impurity bearing titaniferous phase is a claim in relation to matter not in substance disclosed in the specification as filed because claim 1 in the specification as filed only refers to a minor impurity bearing phase. But the claim in claim 4 in relation to the separate minor impurity bearing titaniferous phase is not a matter resulting from the amendment. Prior to the amendment such a matter was disclosed in the specification as it stands. The matter resulting from the amendment is the claim in relation to the mixing of an additive and it is therefore that matter which must be compared with the specification as filed. One does not compare claim 1 in the specification as filed with the claims after amendment to determine what matter results from the amendment; one compares claim 1 in the specification as it stands before the proposed amendment with the claims and specification after amendment to determine what matter results from the amendment. Having thus determined the matter resulting from the amendment, i.e. the mixing of the additive to encourage the separate minor impurity bearing titaniferous phase, his Honour determined that such a matter was disclosed in the specification as filed because the reference to the mixing of additives "to encourage the formation of an acid leachable minor impurity bearing phase" was, in context and on its proper construction, a reference to a separate minor impurity bearing titaniferous phase. It can be seen that additional claim 4 has two relevant aspects. One is the reference to "the separate impurity bearing titaniferous phase". But that reference to the phase being titaniferous is not an amendment to the specification. That is already part of step (i) of claim 1 and optional step 2 and hence part of the specification when construed in the manner referred to immediately above. The second relevant aspect is the reference to "further comprising mixing an additive into the titaniferous ore or concentrate to encourage ...". That is, in our view, a relevant amendment by way of adding a limitation to the three preceding claims. The amendment has the result of claiming that matter ("the additive") as part of the invention. The question is - was that matter in substance disclosed in the specification as filed? WHETHER THE CLAIMED MATTER WAS IN SUBSTANCE DISCLOSED IN THE SPECIFICATION AS FILED? The essence of RGC's submission on this point was that this optional feature must have been disclosed as part of the invention. Alternatively, RGC contended that his Honour had erred in failing to consider whether, in truth, the statement of the optional feature in the second of the additional steps which may be incorporated in the process, in the specification as filed, constituted sufficient disclosure within s 102(1). RGC did not contend that the "additive of claims 4 and 5" had to be "an essential integer" or "essential feature" of the specification as filed. It suggested that such an approach might be "too restrictive against the patentee". Relying fairly heavily on the decision of the Full Court of this Court in Coopers Animal Health Australia Ltd v Western Stock Distributors Pty Ltd (1986) 15 FCR 382, counsel for RGC submitted that the amendment was impermissible because the use of an additive was not disclosed as part of the invention in the specification as filed. We shall deal with the alternative submission first. In our opinion his Honour was quite right in holding that the optional feature was in substance disclosed by the specification as filed. We have set out above the description of what we have termed "the additive option". In our view that description in substance discloses, by way of an option, the matter which is now claimed in additional claim 4 by way of limitation. We think that Coopers can and should be distinguished from the present matter. To start with, Coopers was not concerned with the application of s 102(1) of the Act. The question in Coopers was whether so much of the invention claimed as involved the use of the solvent diethylene glycol mono-butyl ether ("DGBE") was fairly based on a provisional specification. It had transpired that the use of DGBE was the only matter which could possibly have been inventive. As can be seen from the reasons of Fox J at p 390-391, the use of DGBE as part of the matter claimed resulted from further experimentation after the provisional specification had been filed. At 390 his Honour referred to the indirect mention of DGBE in the provisional specification and what we would describe as the relatively unimportant role assigned to DGBE in that document. Accepting for present purposes (but without deciding) that there are analogies between the fair basing test [then contained in s 45A(2) of the Patents Act 1952 (Cth) and applied by the Full Court in Coopers] and the test for whether matter was in substance disclosed in the specification as filed for the purposes of s 102(1) of the Act, we do not think that too much should be made of the references by Fox J (at the top of 391) and Spender J (at 401) to disclosure "as part of the invention" in the sense of being strictly claimed matter. When their Honours refer to "part of the invention claimed in the provisional specification", we think it is acceptable and appropriate to treat the word "claimed" as being a reference to "described" - see for example the discussion at 388. So read, Coopers is easily reconciled with the House of Lords decision in the AMP case. In AMP the relevant feature was clearly disclosed in the specification as an optional part of the device. The House of Lords, by a majority, held that it did not matter that it was an optional part. It was sufficient that the optional part was in substance disclosed in the original specification. That is all that is required by s 102(1). In our opinion, to require such disclosure to be part of the invention would be to place an unnecessary and restrictive gloss on a section which cases such as Ethyl Corporation's Patent [1972] RPC 169 and AMP itself show should be given a liberal interpretation - see Lord Denning MR at 195 in the former case.

WHETHER THE APPELLANT SHOULD BE PERMITTED TO RAISE AN ADDITIONAL GROUND OF APPEAL?

RGC sought to argue that the primary judge ought to have held that the use of an additive as described in the additive option was limited to use "prior to reduction". Because, so it was submitted, additional claim 4 lacked that limitation RGC sought to argue that the claim offended s 102(1) of the Act by claiming matter not in substance disclosed in the specification as filed. It was common ground that this point was not argued before his Honour. Senior counsel for the respondent told us that if this matter had been in issue before his Honour technical evidence could have been led. In those circumstances, in our view, the point should not be raised for the first time at appellate level - see the well‑known passage in Water Board v Moustakas (1988) 180 CLR 491 at 497. CONCLUSIONS For the above reasons, although we would grant leave to appeal, we would dismiss the appeal. I certify that this and the preceding eleven (11) pages are a true copy of the Reasons for Judgment of Justices Carr and Goldberg.

Associate: Dated: 23 October 1998 Counsel for the Appellant: Mr D K Catterns QC with Mr A J Ryan

Counsel for the Respondent: Dr J McL Emmerson QC with Mr P W Collinson

Solicitor for the Respondent: Arthur Robinson & Hedderwicks

SCHEDULE A Description of the Specification as filed

(a) Prior Art Four techniques are described: (1) In the most commonly used technique the titaniferous mineral is reduced with coal or char in a rotary kiln at temperatures in excess of 1100oC. In this process the iron content of the mineral is substantially metallised. Sulphur is added to convert manganese impurities to sulphides. Following reduction the metallised product is cooled, separated from associated char, and subjected to aqueous aeration for removal of virtually all metallic iron as a separable fine iron oxide. The titaniferous product of separation is treated with 2‑5% aqueous sulphuric acid for dissolution of manganese and some residual iron. There is no substantial removal of magnesium or aluminium from the product at any stage, and iron removal is only effected in the aeration step. After calcination the synthetic rutile contains approximately 92% titanium dioxide and 1‑2% iron as oxide. The fact that this process does not remove the magnesium and aluminium in the titaniferous material is a drawback, because those impurities have deleterious effects in the production of white titanium dioxide pigment from synthetic rutile via the chloride process. This is the major use of synthetic rutile. (This technique is known as the "modified Becher process": Australian Patent 516,155 ‑ Hockin and Rolfe). (2) In another technique the ore (ilmenite) is thermally reduced to substantially complete reduction of its ferric oxide content, normally in a rotary kiln. The cooled reduced product is then leached under 35 psi pressure at 140‑150oC with excess 20% hydrochloric acid for removal of iron, magnesium, aluminium and manganese. The leach liquors are spray roasted for regeneration of hydrogen chloride, which is recirculated to the leaching step. (3) A third technique involves subjecting the ilmenite to grain refinement by thermal oxidation followed by thermal reduction in either a fluidised bed or rotary kiln. The cooled reduced product is then subjected to atmospheric leaching with excess 20% hydrochloric acid for removal of the deleterious impurities. Acid regeneration is also performed by spray roasting. (4) The final technique involves thermal reduction of ilmenite (without metallisation) with carbon in a rotary kiln, followed by cooling in a non oxidising atmosphere. The cooled reduced product is leached under 20‑30 psi gauge pressure at 130C with 10‑60% sulphuric acid in the presence of a seed material which assists hydrolysis of dissolved titanium, and consequently assists leaching of impurities. Hydrochloric acid can be used in this process instead of sulphuric acid. The major disadvantages of all processes using hydrochloric acid or sulphuric acid are then pointed out. In summary of the disadvantages of the prior art generally, it is said that existing processes will either not be effective in removing deleterious impurities, or will not be cost effective due to the need to regenerate large quantities of expensive reagents or to neutralise and dispose of large volumes of leachate liquors. It is the object of WIM's invention to overcome or at least alleviate some of these difficulties. (b) Consistory clause The steps involved in the invention are then set out: (i) reducing the titaniferous ore or concentrate under conditions which promote the formation of metallic iron, a major rutile phase and a minor impurity bearing phase; (ii) cooling the product of step (i) in an oxygen free environment; (iii) subjecting the cooled product of step (i) to a first stage leaching or aeration to convert metallised iron into a readily removable form; (iv) removing iron from the product of step (iii); (v) subjecting the product of step (iv) to a second stage leaching to convert other impurity elements to a removable form; and (vi) removing the other impurity elements from the product of step (v). (c) Body of specification The elements of the invention are then described in more detail. The iron present in the ore can be partially reduced to metallic iron by the use of coke, char or coal, gaseous fuels such as hydrogen, natural and petroleum gas, or liquid fuels. The temperature of reduction should be above 900oC in the case of solid carbonaceous reductants and above 600oC in the case of hydrogen-bearing gaseous reductants. The preferred apparatus for reduction is a rotary kiln charged with a solid carbonaceous reductant such as coal, char or coke and operated with a maximum temperature in the range 950‑1050oC. Higher temperatures may be used, but should not exceed 1200oC because at that temperature large quantities of non rutile phases, particularly the anosovite/pseudobrookite like phase (M3O5), will be formed, and there will be a tendency for the mineral to sinter and accrete. Formation of M3O5 rather than metatitinate (M2O3) will result in the need to use more aggressive conditions in leaching. In general, degrees of metallisation in the range 50‑95%, depending on mineral composition, will be suitable. An appropriate degree of metallisation can be achieved by roasting the ore in the kiln for between 30 minutes and several hours at or above 900oC. After cooling and separation of carbonaceous material from minerals, metal may be removed by any suitable means. The preferred method is aqueous aeration, which converts the metal to iron oxides. After separation of the titaniferous product from the iron oxides, the product contains virtually all of its original magnesium, manganese and aluminium. It may also contain substantial quantities of residual iron oxides which have not been metallised or have adhered during an aeration process. Leaching with strong mineral acid, such as hydrochloric or sulphuric acid, is effective in removing these impurities. The preferred leaching is with excess 18‑20 wt% HCI. Greater than 80% removal of iron, magnesium and manganese, and partial removal of aluminium, may easily be achieved by this process. After separation of the leach liquor from the mineral, the mineral product is dried and calcined to remove moisture. The resulting synthetic rutile will contain more than 90% TiO2, depending on the level of impurities in the original titaniferous material and the presence of non titaniferous grains in the original mineral which are retained through the process. A number of optional additional steps can be incorporated in the process. Only one need be mentioned. In involves the mixing of additives, such as chlorides or oxides (eg MnO2), into the titaniferous material prior to reduction in order to redistribute the metallic iron produced via segregation reactions, thereby influencing metallic iron removal, or to encourage the formation of an acid leachable minor impurity bearing phase. Seven examples of laboratory and pilot scale tests illustrating the techniques disclosed are then given. It is not necessary to describe them. (d) The claims The claims with which the specification concludes are: 1. A Process for upgrading the titania content of a titaniferous ore or concentrate which process comprises the steps of:‑ (i) reducing the titaniferous ore or concentrate under conditions which promote the formation of metallic iron, a major rutile phase and a minor impurity bearing phase; (ii) cooling the product of step (i) in an oxygen free environment; (iii) subjecting the cooled product of step (i) to a first stage leaching or aeration to convert metallised iron into a readily removable form; (iv) removing leached or aerated iron from the product of step (iii); (v) subjecting the product of step (iv) to further leaching processes to convert other impurity elements to a readily removable form; and (vi) removing the other impurity elements from the product of step (v). 2. A process according to claim 1 wherein the minor impurity bearing phase is metatitanate (M2O3) or anosovite - pseudobrookite like phase (M3O5). 3. A process according to claim 1 or claim 2 wherein step (iii) comprises blowing air through an agitated aqueous suspension of the cooled product of step (i) in the presence of an agent that promotes the formation of oxides of iron. 4. A process according to claim 1 or claim 2 wherein step (iii) comprises leaching the cooled product of step (i) in a solution of a strong mineral acid. 5. A process according to any one of the preceding claims wherein step (v) comprises leaching the product of step (iv) in an agitated solution of a strong mineral acid. 6. A process according to claim 5 wherein the solution of strong mineral acid has an initial concentration in the range from 4 to 50 wt%. 7. A process according to claim 5 or claim 6 wherein the solution of strong mineral acid is maintained at a temperature in the range from 80 to 150oC. 8. A process according to claim 7 wherein the solution of strong mineral acid is refluxed. 9. A process according to any one of claims 4 to 8 wherein the strong mineral acid is hydrochloric acid or sulphuric acid. 10. A process according to any one of the preceding claims wherein step (i) comprises reducing the titaniferous ore or concentrate with a solid carbonaceous reductant at a temperature in the range from 900oC to 1200oC. 11. A process according to claim 10 wherein step (i) is performed at a temperature in the range from 900oC to 1050oC. 12. A process according to any one of claims 1 to 9 wherein step (i) comprises reducing the titaniferous ore or concentrate with a hydrogen bearing gaseous reductant at a temperature in the range from 600oC to 1200oC. 13. A process according to any one of the preceding claims wherein the process includes the preliminary step of oxidizing the titaniferous ore or concentrate at a temperature in excess of 700oC. 14. A process according to claim 1 wherein the minor impurity bearing phase is anosovite or pseudobrookite and step (v) comprises leaching the product of step (iv) in excess sulphuric acid whilst agitating the heated sulphuric acid for a period of from 15 minutes to 24 hours. 15. A process according to claim 14 wherein the acid has an initial concentration of up to 50 wt%. 16. A process according to claim 1 wherein the carbonaceous reductant is a sub‑bituminous or lignitic coal or char derived therefrom.

SCHEDULE B A description of the material differences between the specification as filed and the specification as accepted on 15 July 1993 The material differences between the two documents can be summarised as follows: (a) In the specification as accepted the first example of prior art is amplified by the statement that the addition of sulphur into the kiln has the negative environmental impact of producing sulphurous kiln exit gases. In the acid leach stage malodorous sulphide gases are commonly produced. The cost of countering these environmental impacts is considerable, and has been influential in preventing the use of sulphur in at least one synthetic rutile installation. (b) A further example of prior art is given in the specification as accepted. In this process ilmenite is first metallised by fluidised bed reduction with hydrogen or carbon monoxide, followed by aqueous aeration for metallic iron removal as separable iron oxides. The titaniferous product of aeration is then optionally acid leached for upgrading from 85‑89% to about 96% TiO2, with removal of residual impurities. The weaknesses of this process are that the use of gaseous reductants is associated with poor single pass reductant utilisation, fluidised beds are limited in maximum temperature when applied to ilmenite metallisation by gaseous reductants since bed sintering occurs at temperatures over 800‑900oC, and metallisation rates at lower temperatures at which effective fluidisation is achieved are low. Consequently, either highly inefficient use of reductant at low intensities is involved, or high pressure processing with reductant recycle is required. (This technique is known as "the Auger process"). (c) After the examples of prior art, and before the summary of the shortcomings of the existing processes, the specification as accepted contains additional material which can be summarized as follows. The prior art is silent on the possibility of metallisation of magnesium and manganese rich ilmenites using solid carbonaceous reductant at temperatures above 900oC followed by aeration for metal removal and acid leaching for removal of magnesium and other residual impurities. At temperatures above about 900oC carbothermic metallisation of ilmenite becomes achievable under practical conditions. However, as presently disclosed, under many conditions a residual impurity bearing titanium phase which cannot easily be leached of all impurities is formed. In particular, the formation of this phase is enhanced by the presence of magnesium in the original ilmenite. There has been no prior disclosure of the required thermal processing or leach conditions which encourage particular impurity bearing phases to form and then be effectively leached. The lower temperature fluidised bed metallisation work has allowed successful leaching of impurities due to a structure present in the residual impurity bearing phase which has not previously been reported as exclusively available under product metallisation conditions at higher temperature. (d) The cost penalties listed in the summary of deficiencies of the existing processes is expanded by reference to the need to operate largely impractical and economically unattractive thermal processing schemes. (e) The consistory clause is amended in one important respect. In step (i) the expression "a separate minor impurity bearing phase" is replaced by "a separate minor impurity bearing titaniferous phase". Changes of a cosmetic nature are made to other steps. (f) The description of step (i) in the body of the specification as accepted no longer refers to gaseous or liquid fuel reductants. (g) The claims defining the invention are reduced by the omission of the former claim 13. The steps of claim 1 have been recast and are: (i) reducing the titaniferous ore or concentrate using a solid carbonaceous reductant under temperature conditions which promote the formation of metallic iron, a major rutile phase and a separate minor impurity bearing titaniferous phase to produce a reduced product; (ii) cooling the reduced product of step (i) in an oxygen free environment to produce a cooled reduced product; (iii) subjecting the cooled reduced product of step (i) to a first stage leaching or aeration to convert metallised iron into a readily removable form to produce a leached or aerated product; (iv) removing iron from the leached or aerated product of step (iii) to produce an intermediate product; (v) subjecting the intermediate product of step (iv) to further leaching processes to form a residue and convert other impurity elements to a readily removable form; and (vi) removing the other impurity elements from the residue of step (v) to produce a synthetic rutile. The principal change is in step (i). The expression "a minor impurity bearing phase" is replaced by "a separate minor impurity bearing titaniferous phase", and "conditions which promote" has been changed to "temperature conditions which promote". The changes to other steps are of a cosmetic nature. Some of the later claims have been amended to reflect those cosmetic changes. Step 12 has been altered by the deletion of the words "at a temperature in the range from 600oC to 1200oC".

SCHEDULE C A summary of the amendments sought by Wimmera

The amendments sought relate to the consistory clause and the claims defining the invention. The amendments to the former reflect certain of the amendments to the latter, and it is not necessary to note them separately. The changes to claims 1 and 2 can be seen from the following marked up claims in which the passages in square brackets are to be deleted and the underlined passages are to be added: 1. A process for upgrading the titania content of a titaniferous ore or concentrate which process comprises the steps of:‑ (i) reducing the titaniferous ore or concentrate using a solid carbonaceous reductant at a temperature of at least 900oC to form [under temperature conditions which promote the formation of] metallic iron, a major rutile phase and a separate minor impurity bearing titaniferous phase containing impurities that are in the titaniferous ore or concentrate to produce a reduced product; (ii) cooling the reduced product of step (i) in an oxygen free environment to produce a cooled reduced product; (iii) subjecting the cooled reduced product of step (ii) [(i)] to a first stage leaching or aeration to convert metallised iron into a readily removable form to produce a leached or aerated product; (iv) removing the readily removable form of the iron from the leached or aerated product of step (iii) to produce an intermediate product; (v) subjecting the intermediate product of step (iv) to [further] leaching [processes] with a solution of a strong acid to form a residue and convert other impurity elements to a readily removable form, said other impurity elements being impurities in the separate minor impurity bearing titaniferous phase in the reduced product of step (i); and (vi) removing the readily removable form of the other impurity elements from the residue of step (v) to produce a synthetic rutile. 2. A process according to claim 1 wherein the separate minor impurity bearing titaniferous phase in the reduced product of step (i) is a metatitanate (M2O3) phase [or a anosovite/pseudobrookite like phase (M3O5)]. Claims 3 to 8, which are to be added, are as follows: 3. A process according to claim 1 wherein the separate minor impurity bearing titaniferous phase in the reduced product of step (i) is an anosovite/pseudobrookite phase (M3O5). 4. A process according to any one of the preceding claims further comprising mixing an additive into the titaniferous ore or concentrate to encourage the formation of the separate minor impurity bearing titaniferous phase in the reduced product of step (i). 5. A process according to claim 4 wherein the additive is an oxide or oxides. 6. A process according to any one of the preceding claims comprising reducing the titaniferous ore or concentrate in step (i) under conditions which minimise the amount of an anosovite/pseudobrookite (M3O5) phase relative to an alternative separate minor impurity bearing titaniferous phase in the reduced product of step (i). 7. A process according to any one of the preceding claims wherein the degree of conversion of iron in the titaniferous ore or concentrate to metallic iron in reduction step (i) is at least 50%. 8. A process according to claim 7 wherein the degree of conversion of iron in the titaniferous ore or concentrate to metallic iron in reduction step (i) is in the range of 50‑95%. Claim 10, which is to be renumbered 9, is to be amended as follows: 9. A process according to any one of the preceding claims wherein the reduction temperature of step (i) is less than [step (i) comprises reducing the titaniferous ore or concentrate with a solid carbonaceous reductant at a temperature in the range from 900oC to] 1200oC. The new claim 10 will read: 10. A process according to any one of the preceding claims wherein step (i) is carried out in a rotary kiln operated at a maximum temperature greater than 950oC. Claim 11 is to be amended as follows: 11. A process according to any one of the preceding claims [claim 10] wherein step (i) is carried out in a rotary kiln operated at a maximum temperature less than [performed at a temperature in the range from 900oC to] 1050oC. Claims 12 to 14 are to be deleted. Claims 12 to 24, which are to be added, are as follows: 12. A process according to any one of the preceding claims wherein step (i) is carried out in a rotary kiln operated at a maximum temperature in the range of 950‑1050oC. 13. A process according to any one of the preceding claims wherein the impurities that are in the titaniferous ore or concentrate comprise any one or more of manganese, magnesium, and aluminium. 14. A process according to claim 13 wherein step (v) converts at least part of the manganese that is in the titaniferous ore or concentrate to the readily removable form. 15. A process according to claim 13 or claim 14 wherein step (v) converts at least part of the magnesium that is in the titaniferous ore or concentrate to the readily removable form. 16. A process according to any one of claims 13 to 15 wherein step (v) converts at least part of the aluminium that is in the titaniferous ore or concentrate to the readily removable form. 17. A process according to any one of the preceding claims wherein step (v) converts at least part of the iron that is not removed in step (iv) to a readily removable form. 18. A process according to claim 13 wherein step (i) concentrates manganese in the titaniferous ore or concentrate into the separate minor impurity bearing titaniferous phase in the reduced product of step (i). 19. A process according to claim 18 wherein step (v) converts a substantial part of the manganese in the separate minor impurity bearing titaniferous phase in the reduced product of step (i) to the readily removable form. 20. A process according to claim 19 wherein step (v) converts at least 80% of the manganese in the separate minor impurity bearing titaniferous phase in the reduced product of step (i) to the readily removable form. 21. A process according to any one of claims 13 and 18 to 20 wherein step (i) concentrates magnesium in the titaniferous ore or concentrate into the separate minor impurity bearing titaniferous phase in the reduced product of step (i). 22. A process according to claim 21 wherein step (v) converts a substantial part of the magnesium in the separate minor impurity bearing titaniferous phase in the reduced product of step (i) to the readily removable form. 23. A process according to claim 22 wherein step (v) converts at least 80% of the magnesium in the separate minor impurity bearing titaniferous phase in the reduced product of step (i) to the readily removable form. 24. A process according to any one of claims 13 and 18 to 23 wherein step (v) converts at least a part of the aluminium in the separate minor impurity bearing titaniferous phase in the reduced product of step (i) to the readily removable form. Claims 3 to 5, which are to be renumbered 25 to 27, are to be amended as follows: 25. A process according to any one of the preceding claims [claim 1 or claim 2] wherein step (iii) comprises blowing air through an agitated aqueous suspension of the cooled reduced product of step [(i)] (ii) in the presence of an agent that promotes the formation of oxides of iron. 26. A process according to any one of the preceding claims [claim 1 or claim 2] wherein step (iii) comprises acid leaching the cooled reduced product of step (ii) [(i) in a solution of a strong mineral acid]. 27. A process according to any one of the preceding claims wherein the strong acid in [step (v) comprises leaching the intermediate product of] step (v) is [in] an agitated solution of a strong mineral acid. A new claim 28 is to be added: 28. A process according to claim 27 wherein the solution of the strong mineral acid has a concentration in the range of 4‑20wt%. Claims 6 to 9 and 15, which are to be renumbered 29 to 33, are to be amended as follows: 29. A process according to claim 27 [5] wherein the solution of the strong mineral acid has a [an initial] concentration in the range of 4‑50 [4 to 50] wt%. 30. A process according to any one of claims 27 to 29 [claim 5 or claim 6] wherein the solution of the strong mineral acid is maintained at a temperature in the range from 80 to 150oC. 31. A process according to claim 30 [7] wherein the solution of the strong mineral acid is refluxed. 32. A process according to any one of claims 27 to 31 [4 to 8] wherein the strong mineral acid is hydrochloric [acid] or sulphuric acid. 33. A process according to any one of the preceding claims [claim 1] wherein the solid carbonaceous reductant is sub‑bituminous or lignitic coal or char derived therefrom.