Bayer Corporation v the Dow Chemical Company
[1997] APO 7
•7 March 1997
official notice
decision of a delegate of the commissioner of patents
Application : No. 610381 in the name of BAYER CORPORATION
Title: STAIN RESISTANT POLYCARBONATE PANELS
Action: Opposition by THE DOW CHEMICAL COMPANY
Decision: Issued .
Abstract
.
Claims 1 to 4 do not comply with section 40 because they are not fairly based on the matter described in the specification. The applicant is allowed 60 days from the date of this decision to propose relevant amendments to overcome these deficiencies
Opposition fails on all other grounds.
In determining whether the invention was obvious and did not involve an inventive step the problem that could be reasonably inferred from the specification as a whole was considered.
patents act 1990
decision of a delegate of the commissioner of patents
Re:Patent Application No. 610381 by BAYER CORPORATION and opposition thereto by THE DOW CHEMICAL COMPANY
background
Patent application 610381 was filed on 24 April 1989 in the name of Mobay Corporation. The application was advertised accepted on 16 May 1991. On 14 August 1991 The Dow Chemical Company (Dow) filed a notice of opposition to the grant of a patent. As the application was filed before, but accepted after, the commencement of the Patents Act 1990, section 59 of the Patents Act 1952 and Chapter 5 of the Patents Regulations 1991 apply in relation to the opposition
A statement of grounds and particulars was filed, and a copy was served on the applicant on 16 September 1991. An amendment to the statement was allowed on 29 April 1993. Serving of evidence was completed on 2 September 1994. On 24 April 1996 in accordance with a request dated 22 March 1996 the name of the applicant was amended to Bayer Corporation (Bayer).
A hearing to determine the matter took place in Canberra on 5 and 6 November 1996. Bayer was represented by Dr Peter Stearne and Mr James Siely both patent attorneys of Davies Collison Cave, Sydney. Dow was represented by Mr Paul Jones and Mr Raymond Evans, both patent attorneys of Phillips, Ormonde and Fitzpatrick, Melbourne.
the specification
The specification is entitled “Stain resistant polycarbonate panels”. It states that the invention relates to stain resistant panels made primarily of polycarbonate resin.
The prior art is then described. Apparently one of the drawbacks to the use of polycarbonate panels in vending machines is that they stain upon coming into contact with staining foods. An object of the invention is to provide polycarbonate based sheets which are resistant to such staining. The prior art cited in the application relates mainly to co-extruded sheets containing a UV absorber. A prior art document of particular note is DE 3617978 which discloses co-extruded sheets based on a polycarbonate resin which sheets are covered by a UV absorbing layer made from a branched polycarbonate resin containing the bis-benzotriazole used in the present invention.
The invention is summarised as providing an improved stain resistant polycarbonate sheet by coating at least one of its surfaces with an adherent layer which comprises a linear polycarbonate resin and a certain bis-benzotriazole. In a preferred embodiment the sheet and the layer are co-extruded and brought into contact at their surfaces while both are at elevated temperature resulting from the extrusion to effect adhesion.
The detailed description of the invention gives details of the type of polycarbonate resins useful in the practice of the invention and preferred options for the bis-benzotriazole. The invention is illustrated by way of an example in which a panel was prepared wherein the adherent layer containing the preferred bisbenzotriazole (5) of the invention and compared to a panel containing the analogous monomer (4) as a control.
The panels were then tested in accordance with ASTM D 2255-68 against various staining food materials and the haze was measured. The following results were obtained:
Invention Control control 0.17 0.15 mustard 0.79 0.87 ketchup 0.33 0.47 mayonnaise 0.55 0.62 relish 0.37 1.12 beer 0.20 0.36 coke* 0.31 0.39 grape juice
chocolate milk0.33
0.710.43
1.11
* Registered trade mark
It was concluded that there is less food staining associated with the sheets of the invention.
The melt stability of the panel of the invention is then discussed. For coextruded panels it is important to have good melt stability for the resin for preparing the adherent layer. It is stated that it was surprising and unexpected that the melt stability of linear polycarbonate which contains the bisbenzotrialzole (5) is better than that of a corresponding branched resin and of either linear or branched resins which contain the analogous benzotriazole (4) of the control. The melt stability was determined according to ASTM D 3835 for resins which contained 10% of the additive. The following results of polycarbonate melt viscosity (Pa.s) were obtained:
benzotriazole
linear branchedbisbenzotriazole
linear branched5 min. at 56.7 sec-1 227 288 443 644 35 113 84 356 423 65
loss (%) over 60 min.84 39
63 86
309 257
30 60
The specification ends with 5 claims. Claim 1 reads as follows:
“A polycarbonate panel comprising a polycarbonate sheet to which at least one of its surfaces there is bonded an adherent layer which includes a linear polycarbonate resin and 1 - 15% of a bis-benzotriazole conforming to
wherein R1 and R2 independent of each other are a hydrogen or halogen atom, a c1 - C12 alkoxy, C7 - C18 aryloxy or a C1 - C10 alkyl, cycloalkyl, arylalkyl or an aryl radical and R3 and R4 independent of each other are a hydrogen atom, a C1 - C10 alkyl, cycloalkyl, arylalkyl or an aryl radical, n is an integer of 0 - 4 and m is an integer of 1 to 3,(Bridge)is eitheror
where p is 0 - 3, q is 1 - 10 Y denotes any of
R3 and R4 independently denote a hydrogen atom a C1 - C10 alkyl, cycloalkyl, arylalkyl or an aryl radical characterised in that said adherent layer is about 5 to 100 microns in thickness and in that only one of its surfaces is bonded.”
Claims 2 to 4 are dependent claims that specify the nature and amount of the bis-benzotriazole. Claim 5 defines a method of preparing the polycarbonate panel of the invention.
There is one important difference between the wording of claim 1 and the corresponding part of the description. The description states that the adherent layer comprises a linear polycarbonate resin and a certain bis-benzotriazole whereas in claim 1 the word includes is used instead of comprising. In the absence of the disclosure of any other component I think it reasonable to construe the word “comprising” in the description as excluding the presence of other elements in the layer. I note that the description also states that “The adherent layer of the invention comprises a polycarbonate resin and about 1 to 15 percent, relative to its weight , of the bis-benzotriazole ...” which seems to exclude the presence of, for example, a branched polycarbonate in the layer.
On the other hand the layer in the claim is not so limited. The word “includes” would not normally suggest or require that the linear polycarbonate is present in any particular amount.
the grounds of opposition
The statement of grounds and particulars of the opposition lists the grounds as set out in sections 59(1) (c) to (i). There was also a statement to the effect that the opponent reserved the right to contest the claim to the priority date. In a decision dated 20 May 1992 (Mobay Corp v The Dow Chemical Co, 24 IPR 379, (1992) AIPC 90-895) the Delegate of the Commissioner decided that the statement of grounds and particulars provided no support for the grounds of opposition as set out in sections 59(1)(c) and 59(1)(d) (prior claiming). These grounds were not pursued.
evidence
Evidence in Support
The evidence in support comprises a number of declarations of which I have summarised the most relevant:
Nancy J Schrock
Dr Schrock is the supervisor of the Polycarbonate Product Development Group of The Dow Chemical Company in the United States. In her declaration she states that in order to establish the relevance and technical accuracy of the experimental data in the opposed specification she directed and supervised further experiments. In her view these experiments showed only the predictable and expected melt viscosity characteristics of the linear and branched polycarbonate resins containing the well-known UV resistance additives.
Darrell James Murray
Mr Murray is the Managing Director of Polycarb Australia. He states that polycarbonate sheet products were in common use in Australia in 1987 and that coextruded polycarbonate sheets were also well known and commercially available in Australia before 22 April 1988. He states that his records show that sheets of MAKROLON LONGLIFE were purchased from Plastral Trading and installed on a customer’s premises on 4 March 1988. (No records were provided.) He understood this product to be a polycarbonate coextruded sheet having a thin surface layer which was stabilised against UV light. The side of the sheet which had the UV-stabilised layer was used in glazing applications as the sun exposed surface of the sheet
Mr Murray refers to exhibit DJM-1 which is a copy of a brochure (undated) obtained from Plastral Trading which identifies Rohm plastics as the source of the product. He also asserts that the product was also known in Australia from advertisements and articles in plastics magazines, copies of which were supplied as exhibits to the declaration. I note from the exhibits that Macrolon is described as a co-extruded polycarbonate sheet with a weather-resistant coating. The composition of the coating is not disclosed.
Euan C Lockie
Mr Lockie has worked in the plastics industry since 1973. His most relevant experience seems to be from 1983 to 1986 as technical manager of GE Plastics Australia involved in development and introduction to the market place of new plastics products including polycarbonate resins and products formed of polycarbonates. From 1986 to 1989 he was quality manager of the same company. Mr Lockie states that he kept abreast of developments in the field by reading trade literature, technical journals and the patent literature.
Mr Lockie states that although it was known that branching agents could be used in the preparation of polycarbonate resins, the most commonly used polycarbonates in Australia before 22 April 1988 were those that did not use a branching agent. He also states that practitioners in Australia were well aquainted with the need to use UV-absorbers to prevent yellowing and loss of gloss. The major class of UV stabiliser used were benzophenones and benzotriazoles. High molecular weight benzotriazoles were preferred due to low volatility.
Mr Lockie states that the technology involved in preparing polycarbonate sheet was well known in Australia prior to 22 April 1988 and the technology used in providing surface coatings, including coextrusion, were well known.
Paul Haemhouts
In the period prior to 1987 Mr Haemhouts worked for Egan Equipment Company in Belgium. He states that he worked extensively with customers providing advice on the utilisation of thermoplastic resin in co-extrusion equipment. Since 1987 he has worked in a similar capacity for Dow Benelux N.V. Mr Haemhouts’ evidence as to “details of the common general knowledge in the art throughout the world prior to the priority date” is similar to that provided by Mr Lockie, supra.
In addition Mr Haemhouts refers to an extract from a publication entitled “Plastics Technology” published in 1973 (Exhibit PH-2A) which list the properties of polycarbonate as including excellent resistance to food staining.
Mr Haemhouts also states that bis-benzotriazoles were known as UV-absorbers prior to the priority date. In particular he states that in 1987 bis-benzotriazole UV-stabilisers became commercially available and as with other benzotriazoles they were known to be particularly suited to use in stabilising polycarbonate. He refers to a Material Safety Data Sheet (exhibit PH-7) relating to a substance available under the trade mark TINUVIN 840 and also referred to as “CGL 084” which was a bis-benzotriazole available from Ciba-Geigy. Mr Haemhouts gives the chemical structure of the compound named in the sheets as the same as the preferred embodiment of the opposed application. He states that the bis-benzotriazoles were promoted for use in polycarbonates and were well known to reduce the volatility problems of conventional benzotriazoles in extruded sheets but this information is not apparent from the data sheets. He concludes that it would be obvious to use them in a co-extruded polycarbonate sheet as a replacement of analogous conventional benzotriazole to reduce the volatility problem.
In respect of the haze tests in the specification, Mr Haemhouts refers to a copy of ASTM D 1003-61 (Exhibit PH-9) which states that the test precision is + 0.1%. He asserts that when the test results are converted to the appropriate number of significant figures and viewed as being + 0.1% it is apparent that the test results do not scientifically prove that any benefit has been obtained. In fact the ASTM states that differences of this order are rarely detectable visually and that the accuracy of test results obtained by different operators and equipment is of the order of + 0.3% haze.
Mr Haemhouts adds that the melt stability data in the specification merely provides inherent properties of compositions disclosed in the prior art and that the conditions used in the melt stability tests are not representative of conditions which would be required to form the claimed polycarbonate panel by the exemplified method in that it uses heating times of 65 minutes whereas a maximum of 5 to 8 minutes is typically required in the polycarbonate melting and sheet extrusion process.
Mr Haemhouts then discusses the disclosure of various patent specifications. I will refer to his observations where appropriate later in this decision.
Alan J Young
Mr Young is the Operations Director of G E Plastics (Australia) Pty Ltd and states that he has access to the business records of that company. This company is and was, prior to 1988, a major manufacturer of polycarbonate compounds and distributed a range of polycarbonate glazing sheets.
Mr Young states that he recalls in September 1987 G E Plastics received 25 kilograms of dimeric benzotriazole UV stabiliser from Ciba-Geigy under the trade name “TINUVIN 840”. (He does not state whether he was aware of the composition of the product at the time of purchase.) He refers to a copy of a computer record (exhibit AJY-1) which is purported to be a record of 1987 purchases by G E Plastics from Ciba Geigy including a sale in September of the “Tinuvin 840”. (It should be noted here that the year of the record is not given on the exhibited copy nor is there a record of the date of receipt of the material.) Mr Young states further that although a data sheet and safety information were received with this purchase he is unable to locate the documents. He refers to copies of the current (1992) sheets which he understands are substantially identical to those provided in 1987 (exhibits AYJ-2 and AJY-3). These sheets give the chemical name and structure of the additive which identify it as the preferred bis-benzotriazole of the opposed application.
He states that at the time of purchase he was aware that the product was developed for UV performance in polycarbonates and was known to have low volatility.
Evidence in Answer
Winfried Georg Paul
Dr Paul is one of the inventors of the opposed application. He sets out the background to the invention, in particular that he discovered that a panel according to the invention showed an unexpected resistance to staining. He states that prior to April 1988 an ongoing problem of concern to Mobay was foodstuff staining of polycarbonate sheets and panels.
In answer to the comments of Dr Schrock regarding melt stabilities, Dr Paul states that the art does not recognise a substantial difference between the melt stabilities of linear and branched polycarbonate resins and, furthermore, the present invention is concerned with compositions and not the resin per se. The behaviour of these compositions cannot be fairly predicted from knowledge of the pure resins. From the results given in the specification the melt stability of linear polycarbonate resin containing the additive is greater than that of a corresponding system based on a branched resin (30% loss of viscosity compared to 60%). This gives the composition a distinct advantage. The results also show the advantage of the bisbenzotriazole compared to the alternative benzotriazole. He does not comment on the relevance of the period of heating time
Silvaram Krishnan
Since 1973 Dr Krishnan worked at both Mobay and Bayer primarily in the field of polycarbonate resins. In a first declaration he confirms the statement by Dr Paul that it was surprising to discover that the panel of the invention showed unexpected resistance to staining.
In a second declaration Dr Krishnan addresses the comments made by Dr Haemhouts on the haze experiments. In particular he points out that the experiments were performed by the same operator using the same equipment.
Heinrich Haehnsen
Since 1985 Dr Haehnsen has been a research officer in the polycarbonate division of Bayer in Germany. He generally supports the comments made by Dr Paul. In particular, he firmly denies the allegation made by Dr Haemhouts regarding the melt stability tests. He acknowledges that bis-benzotriazoles were known for their low volatility but states that the object of the present invention is not related to problems pertaining to volatility.
Evidence in reply
Paul Haemhouts
Dr Haemhouts states that in late 1987 the bis-benzotriazole UV stabiliser MIXXIM LA-31 was promoted in International Plastics Journal (exhibit PH-2 - the publication date in Australia of 17 September 1987 is established elsewhere in the evidence). The journal article refers to the substance as a “developmental benzotriazole”. It states that it is designed to withstand processing temperatures as high as 705F, is recommended for use in polycarbonate and that the company expected its major applications to be automotive. The journal article does not give the chemical formula or identify the product as a bis-benzotriazole.
Nancy J Schrock
In her second declaration Dr Schrock states that, based on her previously described experiments and further data supplied in the declaration, the reported differences in melt stability between stabilised linear polycarbonate and stabilised branched polycarbonate are entirely attributable to differences in the melt stabilities of linear and branched polycarbonate base resins. She also makes some comments as to the validity of the data supplied by the applicants, in particular that the monomeric UV absorber chosen for comparison was already known to be inferior with regard to polycarbonate melt stability.
Dr Schrock refers to copies of three product marketing information sheets relating to dimeric benzotriazole products MIXXIM LA-31, later MIXXIM BB/100 (exhibits NJS-2 to -4). From the dates of these sheets she concludes that the product LA-31 was available at least as early as October 1986. This data was apparently available to journal readers requesting further information offered in the journal articles. The evidence does not establish whether this material was available in Australia.
Dr Schrock then makes reference to a product marketing information sheet distributed by the Applicant with regard to the UV concentrate resins used to prepare sheet structures according to the opposed specification (NJS-5) and a promotional journal advertisement (NJS-6) for sheet structures. In the exhibits only the low volatility and UV weathering properties are mentioned. Dr Schrock concludes that this is evidence that the structures of the opposed specification do not, in fact, exhibit any improved stain resistance properties that can be represented or warranted to the makers or users of the claimed sheet structures and/or that such alleged stain resistance is actually of no consequence.
Dr Schrock refers to US Patent 5108835 (equivalent to DE 3739765) filed in November 1987 by coworkers of the inventors of the opposed specification including Haehnsen. The claims of this patent are directed to double walled sheets with core and coating of a similar composition to the opposed specification for improved UV- and weather stabilisation. The advantages of the sheets are described in terms of low electrostatic chargeability, better weathering and a higher toughness level. This document was published in the US on 28 April 1992.
Robert John Bolton
Since 1977 Mr Bolton has been employed by Ciba-Geigy Australia Limited who are a major supplier of additives to plastics and surface coating industry in Australia. His job involved marketing and providing technical service to customers. Since 1983 he has been responsible for plastic, polymer and coatings additives. He states that as part of his employment he has maintained a close contact with technical staff in the plastics, polymer and surface coating industry.
Mr Bolton states that it was well known to those skilled in the art in Australia prior to 22 April 1988 that benzotriazoles could be used to stabilise polycarbonate panels used in glazing applications. It was well known that stabilisation of the polycarbonate glazing panel could be achieved by applying a coating containing a high concentration of UV absorber, the coating being applied as a lacquer or a coextruded thin layer of polycarbonate.
Mr Bolton states that since 1986 Ciba-Geigy Australia has been selling bis-benzotriazoles as UV stabilisers including a substance known as TINUVIN 1130. He refers to a copy of a brochure relating to TINUVIN 1130 which he states was circulated to customers before April 1988. In the brochure the product is described as the reaction product between methyl-3-[3-(2H-benzotriazol-2-yl)-5-tert.butyl-4-hydroxyphenyl]propionate with polyethylene glycol 300 with an average molecular weight greater than 600. In his declaration Mr Bolton states that the TINUVIN 1130 composition comprises about 55% of a benzotriazole dimer which formula falls within the scope of the dimer of the opposed application. This information is not disclosed in the brochure.
Mr Bolton also refers to TINUVIN 840. He states that the low volatility of TINUVIN 840 was made known to customers in 1987. This low volatility was a property particularly sought after in benzotriazole UV absorbers by those involved in the extrusion and coextrusion of polycarbonate products. He states that 25 kilograms of Tinuvin 840 was sold and delivered to GE Plastics of Dandenong, Victoria during 1987. He refers to a sales record which is identical to AJY-1 and which he states is a copy of an extract from the sales records of Ciba-Geigy for the year 1987. (The year is not stated on the record.)
Priority Date
At the hearing the opponent disputed the priority date of the claims. Mr Jones submitted that the statement in the declaration that the basic application filed in the US on 22 April 1988 was the first application made in a Convention country in respect of the invention the subject of the application was false. He argued that because of this false statement the claim to priority could not stand. In support of this Mr Jones submitted that US Patent 5108835 (an exhibit to the second Schrock declaration) was based on DE 3739765 which was filed on 24 November 1987 and that DE 3739765 disclosed the invention of the opposed application.
I cannot accept Mr Jones’ submission that the contents of US 5018835 fairly indicates the contents of the basic document. DE 3739765 does not form part of the evidence on file. At the hearing I informed Mr Jones that I was not prepared to consider the document at that time and that if he wished to have it considered in the present proceeding he would first have to file an application to file further evidence. Mr Jones declined to do this but stated that the onus was now on the applicant to prove priority. He referred to the decision Fujisawa Pharmaceutical Co Ltd v Banyu Pharmaceutical Co Ltd, (1995) AIPC 91-172 in which the Deputy Commissioner of Patents stated that it was for the applicant to establish any claim to a priority date earlier than the filing date of the specification.
I consider that the applicant has already adequately established the earlier filing date by lodging a declaration claiming Convention priority and filing a copy of the basic document. (The fair basing of the claims on the basic document was not in question.) As DE 3739765 does not form part of the evidence I have no basis to question the statement on the declaration that the basic application filed in the US on 22 April 1988 was the first application made in a Convention country in respect of the invention the subject of the application. I do not believe that in Fujisawa, supra the Deputy Commissioner was contemplating that an applicant should have to individually distinguish their invention from each and every other application they had filed in a Convention country prior to the priority date.
The earlier priority date needs only to be established with certainty if a decision on one of the grounds of opposition is dependant upon it. None of the documents relied upon for novelty was published after the earlier priority date. The opponent has asserted that in establishing that the invention was obvious I should consider that any information that purported to be common general knowledge at the earlier priority date would be even more likely to be generally accepted at the later priority date. I do not accept this assertion and as there is no evidence to the effect that certain common general knowledge was available at the later date but not at the earlier date it is not necessary for me to make a final determination of the priority date in this case.
novelty
The statement of grounds and particulars set out six documents under this ground. At the hearing the opponent relied on only one prior art document, a patent specification, DE 3617978 in the name of Bayer AG and open to public inspection in Australia on 4 March 1988.
The generally accepted test for anticipation is the "reverse infringement" test as set out in Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228 at 235 where Aickin J stated:
"The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement."
Infringement of a claim occurs when each and every one of the essential integers of the claim have been taken (Rodi and Wienenberger AG v Henry Showell Ltd [1969] RPC 367). There is no reason to assume anything other than that all the features of claim 1 are essential features.
The invention disclosed in DE 3617978 is directed to branched thermoplastic polycarbonates with improved protection against UV light. Claim 1 of the citation defines a branched thermoplastic polycarbonate characterised by the fact that it contains a hydroxybenzotriazole of formula I, which compound falls within the scope of formula (3) of the opposed application. The specification further discloses the use of this polycarbonate for the preparation of a multilayered plastic panel in which the layer thickness is 10 to 50 microns and the additive is present in an amount of 1 to 15%. It is clear that this specification discloses a product very similar in structure to that defined by the opposed claims except that it does not disclose the inclusion of a linear polycarbonate in the protective layer.
Mr Jones submitted that in the field of polycarbonate chemistry “linear polycarbonates” are usually named simply by the term “polycarbonate”. He submitted further that as the citation disclosed a panel with a branched polycarbonate coating it was a case of the disclosure of a specific form (branched) disclosing the general form (linear). I do not agree with this submission. It is quite clear from the language of the citation that linear and branched polycarbonates were considered to be distinct polymers and it is also apparent from the opposed specification that the term “linear polycarbonate” in the claim is not a general term that encompasses “branched polycarbonates”.
The opponent also drew my attention to disclosures in the citation regarding linear polycarbonates which are used for comparative purposes. As I will refer to these disclosures again I will quote the relevant passages:
“It has been established that branched polycarbonates which have great importance for the manufacture of high volume, dimensionally stable parts by extrusion become brittle more rapidly than linear polycarbonates when exposed to the same conditions in the presence of the same customary hydroxybenzotriazole UV absorbers. This also seems to be quite understandable since not only molecular cleavages but also branchings have a role in photochemical processes. However, embrittlements are not only the result of molecular degradation processes, but also are produced by branching actions and ultimately by cross-linking reactions. Accordingly, branched polycarbonate in contrast to linear polycarbonate is accompanied by the prerequisites for earlier brittle fracture.
It has now been found that benzotriazole derivatives of structure I improve the UV protection of the branched polycarbonates.
This seems even more surprising since the stabilisers of formula I when added to linear polycarbonates do not differ from the customarily used members of this material class with respect to their protective action.
Accordingly, no reason existed for replacing currently marketed benzotriazole UV absorbers by those of formula I.”
In the examples of the specification four samples are described; two different UV absorbers (a mono- and bis-benzotriazole) were incorporated into each of a branched or linear polycarbonate sample. These samples were made into sheets and tested by irradiation and weathering.
From this disclosure it is clear that the composition comprising the linear polycarbonate and bis-benzotriazole was made, equivalent in composition to the adherent layer of the opposed specification. This is not equivalent to clear and unmistakable directions to use this composition as an adherent layer in a panel with all of the features of claim 1 of the opposed specification. The composition in the prior art is made simply for comparative purposes and not as a layer of a composite structure.
In fact the whole prior art specification seems to teach away from the formation of panels with such an adherent layer because it is clearly stated that the linear polycarbonate does not have the brittle fracture problems of the branched polycarbonates and furthermore the examples show that the bis-benzotriazole offers no advantage when compared to the mono-benzotriazole when used in linear polycarbonates.
I conclude on this point that it has not been established that the claims of the opposed application lack novelty.
inventive step
The problem
The approach to considering obviousness under the Patents Act 1952 was set out in Minnesota Mining and Manufacturing Co. v Beiersdorf (Aust.) Ltd (1980) 144 CLR 253, and summed up by Aickin J in The Wellcome Foundation Limited v V.R. Laboratories (Aust.) Pty Ltd (1981) 148 CLR 262, at pages 270 and 286 in the following terms:
"It is as well to bear in mind that the question of obviousness involves asking the question whether the invention would have been obvious to a non- inventive worker in the field, equipped with the common general knowledge in that particular field as at the priority date, without regard to documents in existence but not part of such common general knowledge ... The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not." (emphasis added).
The opponent’s submissions were based on the argument that it would be obvious to try a polycarbonate sheet with linear polycarbonate top layer bearing bis-benzotriazoles as a UV absorber. Any food staining improvement would be an incidental bonus and the fact that such panels were described as having food staining resistance in the opposed specification had no bearing on the question of obviousness. Mr Jones noted that the claims were not restricted to a food vending machine panel. I was referred to Hallen Co v Brabantia (UK) Ltd, [1991] RPC 195 in which the Court of Appeal found that a patent cannot be valid if it was obvious to select the features of the claim for one purpose, despite the fact that it was not obvious for another.
These submissions require an analysis of the facts on which the decision in Hallen were based. In that case the patent related to a corkscrew coated with PTFE. The coating improved the insertion of the corkscrew but, surprisingly, also dramatically improved the extraction of the cork. The Court of Appeal found that although it was not obvious that the coating would have such an advantageous effect in extracting the cork it would have been obvious to use such a coating to improve the insertion. I find that there are three facts in Hallen that are not matched in the present case:
In Hallen it was found that “any skilled man, even an unimaginative skilled man ...” would have been aware of the problem of the difficulty of inserting the corkscrew and in fact this problem was clearly stated in the specification.
Although a different problem could be formulated in that the device also solved a problem relating to extraction, the function of device and field of endeavour were not changed, the same person skilled in the same art would have been aware of both problems and both problems were associated with the use of the corkscrew for its usual function.
Finally, in Hallen, there was no clear assertion in the specification of the advantage on which the patentee later relied. The specification stated that the primary purpose of the PTFE layer was to increase the ease of insertion. The “surprising” advantage was relied on only in the court proceedings. Thus the Court of Appeal found support for the problem they formulated in the specification in suit. This decision does not provide authority for determining that the problem to be solved is unrelated to the one described in the specification.
It is established law that the skilled man should not be expected to try all combinations unless he had a particular problem in mind and that combination might assist him in solving him (“It must ... be shown to be worth trying in order to solve some recognised problem or meet some recognised need. The uninventive expert ... should not be supposed to be attempting to discover something new, that is, to be striving for inventiveness.”, Beecham Group Ltd.’s (Amoxycillin) Application, [1980] R P C 261).
The opponent has failed to establish in the present case that a problem relating to UV protection existed or that a need was recognised. Although with hindsight it appears that the combination of bis-benzotriazole with a linear polycarbonate might be useful on a panel for UV protection, it appears that at the priority date the existing mono-benzotriazoles were considered to be quite satisfactory and there was no recognised need or inducement for the skilled person to carry out any investigations. There would also be no expectation that the panel might well produce a useful desired result. In this regard refer to the extract of DE 3617978 given above under “Novelty”.
In the present case the opponent asserts that a panel stated to be useful because of its food staining properties is obvious because of its UV resistance properties. Unlike Hallen this involves a different use of the invention and presumably a different, although similar, notional person skilled in the art.
Finally, in the present case the applicant has clearly stated in the specification that the invention is in the field of food stain resistant panels and notwithstanding the fact that the panels defined by the claims are not limited to this use, there is no support in the specification itself for basing a problem in the art of UV resistant panels.
Mr Jones also relied on an extract in a book published in 1973 that stated that polycarbonate sheets were known to have excellent food stain resistant properties and concluded that there was in fact no problem with food staining. On the other hand, the two inventors stated that at the priority date of the claims there was a recognised problem. I accept that a level of food stain resistance that was considered excellent in 1973 might be considered to be unacceptable in 1988 and have no reason to doubt that there was a recognised problem.
I conclude that I agree with Dr Stearne that I should base my analysis on the problem that can be reasonably inferred from the specification as a whole, namely the development of a food staining resistant panel.
Common General Knowledge
The opponent relied on the evidence of Mr Murray, Mr Lockie, Dr Haemhouts, Mr Young and Mr Bolton to establish common general knowledge.
The applicant submitted that as Dr Haemhouts had never worked in Australia and professed no direct knowledge as to the state of the field in Australia he is not competent to give evidence as to the state of the relevant art in Australia. I agree that I should give his evidence on this little weight and will consider it only in so far as it may provide corroboration for a person with first-hand knowledge of the art in Australia.
The applicant objected to Mr Young and Mr Murray in that they give no description of their technical background and that they possess no knowledge in relation to chemistry, more particularly, polycarbonate chemistry. As their evidence relates to what was used and available in Australia rather than the development of plastics and it seems to me that their evidence did not require any special knowledge of chemistry and I find them qualified in this matter.
The applicant submitted that Mr Lockie provided no direct evidence of experience in the development of polycarbonate panels and that his evidence should be given little weight. In particular the documents exhibited to his declaration could not be said to form part of the common general knowledge especially as he does not even state that he had read these exhibits before the priority date or was familiar with them. I agree that the contents of the documents are not necessarily common general knowledge but Mr Lockie seems to make statements in his declaration based on first hand knowledge and these would seem to give an indication as to what was known and used in Australia. The applicant also comments that Mr Lockie’s company did not produce polycarbonate resin, rather it was imported and compounded and that as a consequence he is not qualified to comment on the nature of the polycarbonate resin. As there is no assertion that the invention lies in any particular component of the product it would seem to me that it would be possible for the relevant technology to include persons that use known substances and compositions to form new products such as Mr Lockie. As he was involved in the development of new plastics products including polycarbonate resins I find it quite credible that although he has no experience in the development of particular polymers, he would have some knowledge of the chemical composition of the actual resins themselves.
At the hearing the opponent summarised the common general knowledge in Australia as follows:
· Polycarbonate sheet - particularly for glazing purposes
· Benzotriazoles as UV absorbers for polycarbonate sheet
· Co-extrusion of polycarbonate sheet with adherent polymeric top layer having additives including UV absorbers
· Bis-benzotriazoles promoted and known as UV absorbers for polycarbonate sheet - advantage low volatility suitable for co-extrusion
· Co-extrusion of polycarbonates undertaken at relatively high temperatures - so low volatility additives preferred.
If, as I have decided is correct, I limit this analysis to a consideration of the solution of the problem of food stain resistance most of these points are of very limited relevance. No evidence is directed to whether any benzotriazoles were known to be useful as additives to polycarbonates to improve food stain resistance. The only relevant common general knowledge appears to be basic information relating to polycarbonate sheets and methods of coextrusion. Any knowledge relating to UV-resistance is relevant to the solution of the problem and not to the problem itself. Informed with this knowledge I cannot conclude that the notional person skilled in the art faced with the problem set out in the specification would arrive at the invention defined by the claims.
Even if I did consider obviousness in the light of the problem of UV resistance I would not accept all of the above points to be established common general knowledge. In particular, the following evidence relating to what was common general knowledge about bis-benzotriazoles in Australia at the priority date is not convincing:
Although Mr Murray declares that MACROLON LONGLIFE was purchased and installed on 4 March 1988 (and this is not corroborated by any records) it is not clear at that time if anyone in Australia was aware of the composition of the product. The brochure given as an exhibit does not identify the composition.
Dr Haemhouts’ statement that “in 1987 bis-benzotriazole UV-stabilisers became commercially available” and that they were known to be particularly suited to use in polycarbonates does not necessarily apply to Australia.
Although the journal article relating to Mixxim LA31 was shown to be published in Australia there is no disclosure that the product contains a bis-benzotriazole and it was not established that the contents of the article are common general knowledge.
Similarly, Dr Schrock’s comments relating to information about Mixxim LA-31 and BB/100 do not relate to availability of the information in Australia.
It has not been established that the contents of the patent specification DE 3617978 were common general knowledge.
The statement by Mr Bolton that TINUVIN 840 was promoted and sold in Australia during 1987 is not supported. Even if it has been sold there is no evidence that it formed part of common general knowledge.
Although the copy of the computer record relating to the sale of TINUVIN 840 is undated the evidence of both buyer and seller is that it took place in 1987. However, there is no evidence that the material data sheet relating to TINUVIN 840 dated September 1989 or safety data sheet dated “6/92” referred to by Mr Young were the same as those allegedly available in Australia prior to the priority date, nor that the contents of these sheets or the composition of Tinuvin 840 sold in 1987 were known.
The brochure relating to TINUVIN 1130 did not disclose that it contained some proportion of a bisbenzotriazole, nor that it was this component that made it useful as a UV stabiliser. Also its availability in Australia is not established.
I conclude that it is probable that products containing bis-benzotriazoles as UV absorbers were available in Australia prior to the priority date but it has not been established that there was knowledge that made it obvious to try them in a panel as defined by the claims.
manner of manufacture
The statement of grounds and particulars particularised this ground as follows:
“1. The invention so far as claimed in any claim is at most a mere new or analogous use of a known contrivance. In particular benzotriazole UV-absorbers including bis-benzotriazole were known in Australia before the priority date and their inherent properties were known to make them a preferred UV-absorber for polycarbonate compositions and extruded polycarbonate sheet.”
“2. The invention so far as claimed in any claim is a mere collocation of known integers. In particular it was well known to stabilise a polycarbonate sheet against UV deteriortion [sic] by incorporating a benzotriazole UV-absorber including bis-benzotriazoles. It was well known to use a thin cover layer incorporating UV-absorber to reduce or eradicate the need for UV-absorbers in the substrate or core.”
In the case of Commissioner of Patents. v. Microcell Ltd., 102 CLR 232 at page 251, the High Court held that there was "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 critical question is whether the properties of the bis-benzotriazole which made it suitable for the panel of the invention were "known".
Mr Jones referred me to the recent decision of the Full Bench of the Federal Court in Ramset Fasteners (Aust) Pty Ltd v Advanced Building Systems Pty Ltd (1996) AIPC 91-226; 34 IPR 256. In considering what was known in Australia I should have regard to documents published in Australia. It is not disputed by the opponent that there was no knowledge in Australia of the use of this compound in food stain resistant panels.
In support of the ground of opposition the opponent referred to several patent specifications as well as to the knowledge, use and sale in Australia of materials sold under the trade names of “MAKROLON longlife” and “TINUVIN 840”. In submissions at the hearing it was asserted that “bis-benzotriazole was well known and promoted for use as UV absorber for polycarbonate, and indeed sold for this purpose in Australia”.
It was argued that DE 3617978 discloses all of the individual features of the claimed invention. The opponent asserted that there was no invention in using linear rather than branched polycarbonates in the sheet of the patent. They state that there would be an incentive to use linear polycarbonate because you avoid brittleness and it is cheaper. Again, I refer to the extract of the German specification under the heading “Novelty” above. Although the use of the linear product might be preferable in certain circumstances it was the brittleness of the branched polycarbonate that made it necessary to use bis-benzotriazole.
Similarly, I was referred to EP 110221 in the name of Rohm published in Australia prior to the priority date and referred to in the opposed specification. This specification discloses a panel similar to the panel claimed but containing a mono-benzotriazole instead of the bis compound. Mr Jones submitted that the person skilled in the art would consider the reference to derivatives of benzotriazole in the Rohm specification to include bis-benzotriazoles. It was stated that there was no invention in using the bis compound - known for its low volatility - instead of the mono compound.
My comments under the heading of “Inventive Step” are relevant her. There would be no incentive to try the bisbenzotriazole in the linear polycarbonate as the monobenzotriazole was considered to be quite satisfactory and in fact DE 3617987 teaches that no improvement could be expected.
I conclude on this point that the opponent has not demonstrated that the invention, so far as claimed in any claim, is not a manner of manufacture.
section 40
The following particulars were given
The improvements in stain resistance and/or melt stability alleged in the opposed specification are not achievable from the description provided.
The opponent argued this on the basis of insufficiency (the specification fails to describe how the promise of the invention may be achieved) as well as lack of fair basis (the promise of the invention is not fulfilled by any claim). They submitted that the experimental results did not show any improvement when the test precision was considered and further that the data was not compared to the most relevant prior art, for example sheets where the surface layer contains higher concentrations of other UV absorbers. They also submitted that it was known from 1973 that polycarbonate sheets have good food stain resistance.
I note that the applicant does not have to satisfy the criteria for a selection patent because there was no prior broad disclosure of the invention as claimed. There is no real need to demonstrate any marked improvement over the prior art by way of comparative results in the specification itself. Although the choice of control in the examples is therefore a moot point I cannot agree that it would have been more appropriate to choose the type of panel suggested by the opponent rather than one containing the mono analogue of the bis-benzotriazole. Even with an error of 0.1% the experimental results show a marked improvement in respect of the staining from relish and chocolate milk and at least some improvement from beer and ketchup. Whether the panels of the invention have this property in practice is a matter of utility which is not considered in opposition proceedings.
Similarly, there was a lot of debate at the hearing as to the relevance and accuracy of the melt-flow data. The opponent submitted that the claimed improvements were within the tolerance errors of the test and further that the claimed improvement over 35 to 60 minutes was irrelevant to a process that takes 5 to 8 minutes. Also, the monomeric UV absorber chosen for comparison was already to be known to be inferior with regard to polycarbonate melt stability. It seems to me from a fair reading of the specification that these melt-flow characteristics were only ever seen as an incidental advantage and relevant only to the preferred embodiment in which the layers are co-extruded. The experimental data presented is largely irrelevant in deciding the validity of the claims.
The claims are not fairly based in that they are not restricted to food stain resistant vending machine panels.
The application describes a novel product which was developed in the field of food resistant panels. Mr Siely drew an analogy with a novel compound developed for the use in a particular disease. It is established law that such a compound can be claimed per se (it being accepted that the use in the treatment of the disease is an inherent feature of the compound). Although the panels of the opposed application are not limited by the use of the term “food resistant vending machine panel” or an explicit limitation that they be suitable for such use, there is no evidence to suggest that any panel with the features as described does not embody the inventive concept of the application. It appears from the specification as a whole that a panel with these features will have food stain resistant properties and so it could be said that this feature is an inherent feature of the panel. If in fact the claims defined such a panel and that panel did not exhibit food stain resistance then such a claim would fail on utility which is not considered in opposition proceedings.
The preceding discussion is directed to the panel as described. As noted above in my discussion of the specification, claim 1 is not limited to the features of the described invention and is therefore not fairly based on the description. The use of the word “includes” means that the adherent layer may contain components other that the linear polycarbonate resin and bis-benzotriazole. The amounts and nature of any other components are not defined and it is not at all certain that the panels as claimed would have the properties of food stain resistance.
Claims 2, 3, and 4 are similarly not fairly based.
The claims are not fairly based in that they are not restricted to the one UV absorber tested and alleged to have food stain resistance/melt flow advantages.
The bis-benzotriazole in the panel is defined by a generic formula which encompasses a number of structurally related compounds. If it could be fairly predicted that such compounds formed a class of compounds that would achieve similar results then the claim is fairly based. I note that although the formula has between two and fourteen optional substituents the main basic bis-benzotriazole structural framework with either an alkylene or ester bridge of the compound is consistent. In the absence of any expert evidence to the contrary I am prepared to accept that the generic formula is reasonable in the circumstances and that the claim is not speculative.
Claim 1 is not clear in that words are apparently missing from lines 3 to 4.
It seems that the part of the claim in question is “to which at least one of its surfaces there is bonded an adherent layer” and that the word “upon’ or “on” should be inserted before “at least”. While the language of the claim may not be elegant I do not agree that it causes any real lack of clarity in respect of the meaning or scope of the claim.
Claims 2, 3, and 5 are not clear in that the word “about” is used to qualify a range.
While I would agree that in some circumstances the word "about" can introduce lack of clarity, I do not agree that this is the case here. The particular ranges in question need to be read as having the tolerances which the skilled addressee would usually read into the ranges.
conclusion
Claims 1 to 4 do not comply with section 40 because they are not fairly based on the matter described in the specification. I allow the applicant 60 days from the date of this decision to propose relevant amendments to overcome these deficiencies.
The opposition fails on all other grounds.
costs
It is usual in matters before the Commissioner for costs to follow the event. At the hearing both parties submitted that I should vary the scale of costs to allow for the appearance of two attorneys because of the complexity of the case. Variation of the scale is appropriate to allow the recovery of costs reasonably and properly incurred, if the scale provides inadequate recompense. The scale is not varied merely by consent of both parties. I am not satisfied that the parties have demonstrated that the present case was of sufficient complexity to justify varying the scale.
In the present case the opponent failed on the grounds of manner of manufacture, novelty and obviousness and succeeded only on a relatively minor matter of lack of fair basis which should be able to be overcome by a simple amendment. In these circumstances I consider it appropriate that I should award one half of the costs against the opponent according to the scale as set out in Schedule 8.
Vivienne Thom
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Davies Collison Cave, Sydney
Patent attorneys for the opponent : Phillips, Ormonde and Fitzpatrick, Melbourne
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