Minnesota Mining and Manufacturing Co v Beiersdorf - [1980] HCA 9 - HCA 1980 case summary — Zoe

CTHHCA

Minnesota Mining and Manufacturing Co v Beiersdorf

[1980] HCA 9

High Court of Australia|1980-04-16|Before: Wilson JJ, Stephen J, Mason J

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Source facts

Court

High Court of Australia

Decision date

1980-04-16

Before

Wilson JJ, Stephen J, Mason J

Source

Original judgment source is linked above.

Judgment (172 paragraphs)

[1]

For the reasons given by Aickin J., I am of opinion that claims 7, 8 and 9 of the first appellant's patent were valid and have been infringed. I would therefore allow the appeal and dismiss the respondent's cross-appeal.

[2]

I may say that I have examined the backing (Ex. Y) and the Leukopor tape (Ex. X) by hand pulling such as would be applied to the finished product in ordinary use as a surgical tape and I found that neither the backing nor the tape was extensible, though, like Aickin J., I found that the expenditure of greater effort produced a small degree of extension.

[3]

This is an appeal by Minnesota Mining and Manufacturing Co. and its subsidiary 3M (Australia) Pty. Ltd. (the appellants) which were the plaintiffs in a patent suit brought in the original jurisdiction of this Court in which Beiersdorf (Australia) Ltd. (the respondent) was the defendant. The proceeding was heard before Murphy J. who dismissed the suit on 15th March 1978. The first appellant (an American corporation) was the registered proprietor under the Patents Act 1952-1969 Cth of letters patent No. 260,604 dated 5th April 1961 for an invention entitled "Breathable Adhesive Tapes". The second appellant was a corporation incorporated in the State of New South Wales and had been granted by the first appellant an exclusive licence to make, use exercise and vend the invention throughout Australia. The appellant claimed that the defendant had infringed and threatened to continue to infringe the letters patent and sought an injunction restraining further infringement and an account of profits or an inquiry as to the loss and damage sustained by the appellants by reason of the infringements. The respondent denied infringement and also said by way of defence that the letters patent were and at all material times had been invalid. The respondent also counterclaimed for revocation based on the particulars of objection served with the statement of claim. The particulars were amended on 11th November 1975 and specified most of the possible grounds of objection. However in this Court the principal ground of invalidity relied upon was the particulars of objection which alleged that the invention as claimed in each of claims 7, 8 and 9 was obvious in the light of what was known in Australia at the priority date. Reliance was placed on seven prior publications, namely, two Australian patent specifications, one French patent specification, one United Kingdom patent specification and three United States patent specifications. The particulars of objection also alleged want of novelty but that point was not relied on before the trial judge, but in a written reply in this Court the respondent sought to rely on that ground. This aspect is referred to below.

[15]

The specification then says that: The preferred backing is a nonwoven compacted tissue formed of interlaced staple rayon (or equivalent) textile fibers (having a length of about 1 to 2 inches (2.5 to 5 cm)) which is unified by impregnation with a water-insoluble rubbery fiber-binding sizing agent (such as a rubbery acrylate polymer latex) that coats the individual fibers (without filling the interstices) and bonds them together at their crossing points; such as to result in a thin, pliable, inextensible, resilient, water-resistant, translucent, porous, clothlike fabric that is strong and tough enough for surgical tape usage and yet is finger-tearable so that the tape can be applied from a roll without having to be cut. Rubbery, as used herein, refers to a material which is elastic and resilient as distinguished from materials which are plastic or brittle and nonelastic. This unified nonwoven reticular fibrous backing has a very large number of minute interfilar passageways per square inch (or square centimeter) and is highoy [sic] porous. The reticulate structure of the backing performs a physical function in bringing about the transformation of the applied adhesive coating from a non-porous to a porous state during manufacture of the tape, by the process presently to be described, and the preferred nonwoven type of backing is particularly well suited to perform this function. The specification then states: In any case, the viscoelastic pressure-sensitive adhesive is applied to the porous backing fabric in such a way as to provide thereon a continuous soft sticky viscid coating containing a volatile vehicle which is in small enough proportion to avoid wicking or penetration of the adhesive through the body of the porous backing, when it is promptly dried after application. The volatile vehicle is, however, present in sufficient substantial proportion to enable the viscid adhesive coating to penetrate into and interlock with the backing and to have a tendency to be drawn by capillarity into the pores. Further drying of this semi-dry adhesive coating results in progressive loss of the residual volatile vehicle and a shrinkage of the coating. These capillary and shrinkage effects produce a strain in each tiny portion of the viscoelastic adhesive film which bridges a backing passageway, and in yielding to this strain one or more minute openings (pores) are autogenously formed therein. In this way the entire adhesive coating, during drying, autogenously develops a vast number of closely spaced pores, producing a microporous structure in an adhesive film that remains visibly continuous.

[97]

However there are some things which the microphotographs in evidence demonstrate which are not in dispute between the parties. I have referred above to the fact that when viewed under the microscope the surface of the nonwoven backing is by no means smooth and continuous as it appears to the naked eye but, as the specification makes clear, highly porous so that the surface is markedly discontinuous and the random interlacing of the individual fibres makes that part of the surface rough and discontinuous, in both horizontal and vertical planes. Mr. Simmens had taken a substantial number of both optical and electron microphotographs at varying degrees of magnification, and he gave evidence about them, in particular about certain of the photographs which comprised Ex. 8.1 and 8.2. He said, after discussing the particular photographs, "I find the adhesive to be interlocked securely with the backing material and the whole to be a unitary integrated structure." He pointed out in relation to certain of the photographs (LT 13-16) that the outlines of individual fibres were clearly visible on the surface and were coated by the adhesive. He said in a written report admitted in evidence that photographs LT 13 to LT 18 revealed that "a smooth unbroken surface can be seen commencing at the upper adhesive face and continuing down into the pore and coating one or more fibres". He also referred to photographs LT 23 to LT 31 and said that the appearance of a cross section of the tape, when examined under the electron miscroscope, revealed fibres within the adhesive layer and that the particular microphotographs of the cross section showed fibres positioned very close to the adhesive surface. He based his conclusion that the adhesive interlocked securely with the backing material and the whole was a unitary integrated structure upon the disposition of the fibres on the adhesive side of the tape as viewed by optical and scanning electron microscopes and on his observation of the continuity of the upper (adhesive) surface down into the pores and around the individual fibres. The respondent's expert witness on this matter was Professor Ayscough. Dr. Mueller disclaimed any skill in the interpretation of microphotographs but said that the manufacturing process used at or about the relevant time was as described in the respondent's patent (Ex. 17 - Australian Patent No. 418938), save for the thickness of the adhesive applied to the backing. That specification states that:

[101]

Professor Ayscough was one of the expert witnesses called by the respondent who dealt with this same matter. It may be noted that at no stage in his evidence did he say that there had been no penetration of the adhesive into the backing of the Leukopor tape and he refers to the manufacturing process and states that the rollers exert very high pressure on the adhesive and the backing. However he said, contrary to what is said in the specification, that the purpose of the passing through the rollers under very high pressure was "not to achieve an adhesive bond, the purpose is to bring the two layers into intimate, physical contact but more particularly to rupture the membrane around the vesicles and to ensure that the vesicular film is porous". The specification however makes it clear that the purpose of this is to create adhesion as well as to rupture the membrane of the adhesive but it is significant that Professor Ayscough acknowledged that there was "intimate physical contact". The nature of the nonwoven backing makes it clear that no "intimate physical contact" could occur without there being penetration for some distance into the highly porous material. Professor Ayscough maintained however that the degree of penetration was minimal. The microphotograph ( LB 1 in Ex. 8.2) shows the defendant's backing before the adhesive is applied to it and clearly demonstrates the open irregular surface and the open structure of the interior. The effect of the calendering between the rollers is seen in Ex. 8.2 when photograph LT 13 which is the tape with the adhesive on it is compared with photograph LB 1. Professor Ayscough did not advert to the fact that according to the patent specification the chemical reaction only takes place during the subsequent stage if heating is applied. Professor Ayscough produced certain photographs, which had been taken by a Dr. Robinson, of the respondent's tape and certain diagrams which he had prepared reproducing what was visible by the use of the microscope. He had drawn a line on certain of those photographs marking the boundary between the adhesive layer and the backing of the defendant's tapes but admitted in cross examination that there were fibres above the line and appearing in the area which he said represented the adhesive. He also observed that the backing was "quite irregular".

[165]

Mr. Rose, a surgeon practising in Sydney also gave evidence. He had numerous qualifications in surgery, being a Fellow of the Royal College of Surgeons of England and of the Royal Australian College of Surgeons and the American College of Surgeons. He had for a substantial time been Honorary Surgeon at the Royal North Shore Hospital and other hospitals. He said that he first became aware of Micropore tape in approximately 1963-1964 and that prior to that time during his experience as a surgeon since graduating in 1933 the type of tape used was that known as "Elastoplast" or its equivalent which consisted of a woven backing applied to which was an adhesive generally containing zinc oxide. He said the disadvantages of those tapes were that they caused irritation to patients on application and removal and that in about ten per cent of cases caused allergic reactions or blistering. They did not permit the skin to breathe and irritation of the skin resulted and the risk of infection was increased. He said that because of those disadvantages it was necessary to disturb dressings sooner than was desirable and that as it was not possible to see through the tapes discharge from wounds was not visible, and the process of healing could not be estimated. He also said that they were difficult to handle with rubber gloves in an operating theatre because of the extreme stickiness and they had to be cut with scissors. He said that since about 1963-1964 he had used Micropore tape and that its usage had increased to the extent that it was used for all dressings after operations in the vast majority of cases. He said that it had a number of advantages including that under normal conditions of surgical use it did not stretch with normal hand pulling but could be easily torn. He stated that it did not irritate the skin with normal patients in any way and that all pores in it allowed sweat and other secretions of the skin or the wound to seep through and evaporate and that the progress of healing could be observed to a "fair extent". He also said that it was easier to handle in the operating theatre with rubber gloves and that the fact that the skin could breathe through the minute pores was one of its great advantages, whilst the fact that it permits skin closures without stitches where there are small wounds was also a great advantage. Finally he stated that use of Micropore had obliterated complaints which he had heard for many years from patients and other practitioners arising out of the defects of the older type of surgical tape.