The B.F. Goodrich Company v ICI Australia Operations P/L

[1995] APO 8

official notice

decision of a delegate of the commissioner of patents

Application        :    No. 606073 in the name of THE B.F. GOODRICH COMPANY.

Title:    Process for making film grade PVC.

Action:    Opposition by ICI AUSTRALIA OPERATIONS P/L under Section 59 of the Patents Act 1952.

Decision:    Issued            .

Abstract:    Ground of obviousness established.

Section 40 , prior publication, manner of manufacture and prior use also discussed.

patents act 1990

decision of a delegate of the commissioner of patents

Re:Patent Application No. 606073 by THE B.F. GOODRICH COMPANY and opposition thereto by ICI AUSTRALIA OPERATIONS P/L under Section 59 of the Patents Act 1952.

background

Patent application number 77447/87 was lodged on 26 August 1987 by The B.F. Goodrich Company ("BFG") and claimed priority from US application number 904429 filed on 5 September 1986. The application became open to public inspection on 10 March 1988.

Acceptance of the application and complete specification was advertised on 31 January 1991, the accepted application then being allocated serial number 606073.

A notice of opposition to the grant of a patent was filed on 30 April 1991 by ICI Australia Operations P/L ("ICI"). The evidence stages of support, answer and reply were completed by 30 March 1992, 30 December 1992 and 30 September 1993, respectively. On 21 December 1992 the applicant filed a request to amend the complete specification and these amendments were subsequently advertised allowed on 7 October 1993.

The matter was heard in Melbourne on 17 August 1994. BFG was represented by John McCormack, patent attorney of Griffith Hack & Co.  ICI Australia were represented by Elizabeth Eadie, patent attorney of Davies Collison Cave, assisted by Julie Wilkie, patent attorney of Davies Collison Cave and Michael Angliss, intellectual property officer with ICI Australia.

As the application was advertised accepted before the commencement of the Patents Act 1990, the opposition is proceeding under the provisions of the 1952 Act and regulations by virtue of section 234(3) of the 1990 Act and Regulation 23.3 of the Patent Regulations 1991.

The grounds relied on in the notice of opposition are all the grounds available under section 59(1) of the Patents Act 1952. At the hearing, however, submissions were made only in relation to grounds (e), (f), (g), (h) and (i), i.e. prior publication, manner of manufacture, obviousness, novelty and section 40.

Following the hearing, ICI applied for special leave to lodge further evidence. The application for special leave and the further evidence were served upon BFG on 10 October 1994. BFG did not object to the application to serve further evidence. By letter dated 21 November 1994, the parties were notified that I had decided to grant the application for special leave. On 21 December 1994, Mr McCormack provided written submissions on behalf of BFG, in response to the further evidence adduced by ICI, but did not file any material in declaratory form in accordance with the provisions of regulation 59(6) to the 1952 Act.

THE SPECIFICATION

The background to the invention is expressed in the specification of 606073 in the following terms:

"Heretofore, polyvinyl chloride (PVC) has typically been produced in large reaction vessels. A problem often encountered is a formation of gel during the polymerisation of the resin. Gel can be reduced by thoroughly cleaning the reaction vessel periodically or after a production run. However, cleaning of the reaction vessels requires extensive down time and severely hinders the production rate of the resin.

It is known that the use of secondary dispersants enhance build-up on reactor walls which result in fisheyes in subsequent charges. Accordingly, the reactor must be periodically opened and cleaned."

The specification of 606073 relates to a process for producing polyvinyl chloride (PVC) resins and copolymers thereof by polymerising vinyl chloride type monomers in a reaction vessel coated with an aromatic compound by utilising a primary dispersant system containing a high hydrolyzed polyvinyl acetate in combination with a secondary low hydrolyzed polyvinyl acetate dispersant.

The specification indicates that it is known that coating the internal surfaces of the reactor with an aromatic compound inhibits polymer build-up, it is known that a primary dispersant system aids in suspending the monomers during the suspension polymerisation, and it is known that the use of a secondary dispersant yields a more uniform or symmetrical PVC particle or resin, as well as increasing its the porosity.

At page 12 lines 8 to 14 of the specification it is stated that:

"The hydrolysis reaction of polyvinyl acetate is typically carried out in a suitable solvent, for example, methanol, ethanol, methyl acetate, ethyl acetate, benzene, acetone, and mixtures thereof with water, as described in "Polyvinyl alcohol, Properties and Application", edited by C.A. Finch, John Wiley & Sons, (1973).

The thrust of the invention then appears to be indicated at page 12 lines 15 to 24 of the specification, as follows:

"It is an important aspect of the present invention that the secondary dispersant be separated from organic solvents so that the aromatic inhibitor is not depleted, removed, or the function thereof interfered with during the polymerisation of the various vinyl chloride type monomers. Thus, secondary dispersants are utilised which are generally free, that is, contain about 5% by weight or less, of organic solvents such as methanol, and the like. A suitable dispersant is a polyvinyl acetate having a low degree or level of hydrolysis .... Examples of such secondary polyvinyl acetate dispersants are well known to the art and to the literature. Specific examples include   Alcotex 55/002H having approximately a 55% level of hydrolysis."

The patent concludes with ten claims. Claim 1 reads as follows:

"A process for producing a vinyl chloride type resin having a low gel content, comprising the steps of:
adding at least one vinyl chloride type monomer to a reaction vessel coated with an aromatic inhibitor polymer build-up compound, adding to said vessel an effective amount of a primary dispersant system containing a 70 to 98 mole percent hydrolyzed dispersant and an optional modified cellulose ether dispersant and adding an effective amount of a 10 to a 60 mole percent hydrolyzed secondary dispersant which contains 5% by weight or less of an organic solvent to produce a vinyl chloride resin having a low gel content upon polymerization, and
polymerising said vinyl chloride type monomer in said coated vessel to produce a low gel vinyl chloride type resin, and repeating said process and producing a low gel content vinyl chloride type resin under continuous production conditions free of cleaning said reaction vessel."

Claims 2 to 5 are dependant on claim 1.

Claim 6 reads as follows:

"A polyvinyl chloride resin produced in a reaction vessel made by a process, comprising:
coating the internal surfaces of the reaction vessel with an aromatic inhibitor polymer build-up compound, adding a vinyl chloride type monomer to said vessel, adding an effective amount of a primary dispersant system containing a 70 to 98 mole percent hydrolyzed dispersant and an optional modified cellulose ether dispersant,
adding an effective amount of a 10 to a 60 mole percent hydrolyzed secondary dispersant which contains 5% by weight or less of solvents, and
polymerising said vinyl chloride type monomer to produce a low gel vinyl chloride type resin."

Claims 7 to 10 are dependant on claim 6.

EVIDENCE

The evidence in support consists of three declarations.

Two of the declarations are by Elizabeth Eadie. These declarations serve to present 24 exhibits, which are copies of patent specifications, copies of abstracts of patent specifications, copies of extracts from two text books, a trade brochure, copies of a purchase order and an invoice, and certificates issued by the Patent Office attesting the dates that certain documents became open to public inspection in the Australian Patent Office.

The other declaration is by David N. Harris of 16-20 Beauchamp Road, Matraville, New South Wales, Australia and is dated 25 March 1992 (referred to as the first Harris declaration). Mr Harris is employed by ICI Australia as Product Development Manager of the Vinyls Division of their Plastics Group. His declaration provides the expert evidence in support of the opposition, serves to present a copy of an extract from a text book, and refers to the exhibits attached to the Eadie declarations.

The evidence in answer consists of two declarations. The first, by John David McCormack, provides comments on aspects of the Harris declaration dated 25 March 1992 .

The second declaration is by Joseph Edward Fattlar of 27412 Dellwood Drive, Westlake, Ohio, USA. Mr Fattlar is employed by BFG as a supervisor in their GEON PVC Resin Research and Development Group. This declaration provides the expert evidence in answer to the opposition and exhibits a rating scale for reactor build-up used by BFG.

The evidence in reply consists of a further declaration by David N Harris (referred to as the second Harris declaration) which includes as exhibits a copy of a patent specification and a copy of a trade brochure, declarations by Catherine Sexton and Peter Griffiths providing evidence of the dates that material became open to public inspection, and two declarations by Elizabeth Eadie which serve to present as exhibits copies of 9 patent specifications, a copy of an extract from a text book, and copies of invoices, purchase orders and associated correspondence.

The further evidence consists of a further declaration by David N. Harris (referred to as the third Harris declaration) which includes as exhibits copies of "recipes", details of a CAS registry number, a product specification, details of a dispersion test, product test results, and extracts from product sales data.

SUBMISSIONS

In summary, Ms Eadie's submissions for the opponent were as follows:

Section 40

-  The claims are not fairly based in that the aromatic build-up inhibitor compound is not limited in accordance with the description at page 6 lines 30-32 wherein it is stated that: "The important criterion is that the phenolic compound for use in this invention have a functional phenolic (-OH) group and an aromatic backbone". All of the exemplification in the application relates to phenolic inhibitor compounds.

-  Claim 6 is not fairly based in that it does not include the essential feature of polymerising the vinyl chloride under continuous reaction conditions free of cleaning the reaction vessel.

-  In claims 1 and 6 the scope of the term "low gel content" is indeterminate, as is the term "the gel content is 10 or less" in claim 5. In the description at page 13 line 26 to page 14 line 1, gel count is said to have been determined by a procedure involving counting of fisheyes but does not say over what area. There is no standard procedure for determining gel content or count in the industry.

-  The description is not clear in that the characteristics of the secondary dispersants used in Example 2 are not clearly specified.

Prior Publication

-  The invention is prior published by the Encyclopedia of PVC, Edited by Nass & Heiberger, 2nd Edition, which publication was available to the public in Australia prior to the priority date of 606073.

-  Every essential element of claim 1 of 606073 is disclosed in the Encyclopedia of PVC, 2nd Edition.

-  If the term "secondary suspending agent " in the citation was read in the light of the common general knowledge, the person skilled in the art would have understood that term to include Alcotex 55/002H which was part of the common general knowledge. As authority that terms in a citation should be read in the light of the common general knowledge, Ms Eadie referred me to Acme Bedstead v Newlands, (1937) 58 CLR 689 .

Obviousness

-  At the priority date of 606073 the cited prior art relating to primary and secondary dispersing agents and to build-up suppression coatings was common general knowledge to the person skilled in the art in Australia. If, in a process utilising a build-up suppression coating and a primary and secondary dispersant system, the secondary dispersant used had a high methanol content and there was a problem with fisheye formation leading to build-up of gel in the reactor, then the solution to that problem was already part of the common general knowledge in Australia and was obvious from EP,A,123364 which discloses that fisheye formation was reduced when a secondary dispersant which did not contain methanol was used compared to when an otherwise similar but high methanol containing secondary dispersant was employed.

-  When the low methanol secondary dispersant Alcotex 55/002H came onto the market it would have been obvious to try it in place of a high methanol dispersant which it was common general knowledge was flammable and consequently expensive to transport, store and handle. As authority on an analogous situation, Ms Eadie referred me to Asahi Kasei Kogyo KK v WR Grace & Co, (1992) AIPC 90-847 at pages 38088-89.

-  Neither 606073 nor EP 123364 make any mention of the distinction referred to in the Fattlar declaration between temporary and permanent fisheyes.

Manner of Manufacture

-  The present invention merely involves the substitution of one secondary dispersant (having a high methanol content) by another secondary dispersant (having a low methanol content) which was available on the market in Australia before the priority date of 606073.

Ms Eadie referred to Exhibit EE22 which is a copy of a Harco trade brochure dated April 1986 which she said shows that Alcotex 55/002H has only one purpose and that is as a secondary dispersant. The present process therefore amounts to no more than the use of a known product (of which Alcotex 55/002H is an example) for a purpose for which its attributes and suitability were hitherto well known.

-  As authority on the issue of manner of manufacture in an analogous situation, Ms Eadie referred me to the decision in Asahi v Grace (supra) at page 38089.

Prior Use

-  In the first and second Harris declarations there are clear statements that, prior to the priority date, ICI manufactured PVC in Australia by the process of the invention of 606073. Copies of invoices exhibited to the first Harris declaration show that, prior to the priority date, ICI had acquired in Australia all of the components required to perform the process of the invention.

-  As authority that commercial use in a factory is not secret use , Ms Eadie referred me to Bristol-Myers Co. (Johnson's) Application, [1975] RPC 127.

In summary, Mr McCormack's submissions for the applicant were as follows:

Section 40

-  The skilled addressee would understand all of the terms used in the claims.

-  The claims are fairly based on the disclosure. Features of the invention alleged to have been omitted from the claims are in fact advantages of the invention which are not required to define the process of the invention.

-  The examples in the specification clearly show how the invention is to be put into practice.

Prior Publication

-  None of the documents cited by the opponent, including the Encyclopedia of PVC, 2nd Edition, disclose the combination of features which characterise the invention claimed in 606073.

-  The particular type of secondary dispersant defined as being used in the invention was chosen from a wide range of known secondary dispersants.

Obviousness

-  The invention is the discovery that a PVC resin with a low gel count could be produced by utilising an aromatic inhibitor polymer build-up compound (reactor coating) while employing a secondary dispersant containing less than 5% methanol. That the combination of features of the process of the invention would produce low gel resins was an unexpected result because none of the cited prior art suggests that, or addresses that it was a problem that, a high methanol dispersant would interact with the specified reactor coating to diminish its effectiveness. The combination of features of the present invention was inventive in the context of the problem.

-  Items of cited prior art may have been shown to be common general knowledge in some art but were not common general knowledge in the art of the present invention which is concerned with the interaction between the reactor coating and  the secondary dispersant.

-  Mr McCormack referred me to Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Limited, (1980) 144 CLR 253, Wellcome Foundation Pty Ltd v VR Laboratories (Aust) Ltd, (1981) 148 CLR 262, Beecham Group Limited's (Amoxycillin) Application, (1980) RPC 261.

Manner of Manufacture

-  The invention could be viewed as the new use of old integers to obtain an unexpected advantage.

Prior Use

-  insufficient evidence has been provided to corroborate the statements in Mr Harris's declarations that the invention had been prior used in Australia.

-  Even if the exhibited invoices showed that ICI had acquired, prior to the priority date, the components needed to perform the process of the invention, there was no evidence that those components had been used together in the same process. Furthermore, although an exhibit showed that ICI had purchased something called BUSB79, it was not clear that this was a build-up suppressant let alone one of the type defined for use in the invention.

-  On the topic of the law in Australia on secret use, Mr McCormack referred me to The Law of Intellectual Property by S.Ricketson published in 1984 by The Law Book Co. Ltd., Sydney.

DECISION

Section 40

In claims 1 and 6 the aromatic inhibitor build-up compound is not further defined as being phenolic. However, at page 9 line 6 to page 10 line 10 of the description, compounds which are aromatic but not phenolic are clearly set forth as being suitable for use as the inhibitor in the process of the invention. Therefore, and from a reading of the specification as a whole, I do not agree with the opponent's submission that it is an essential feature of the invention that the inhibitor is necessarily a phenolic compound. On this point, I consider that claims 1 and 6 are fairly based.

At page 15 lines 9 to 11 of the description, it is stated that "the necessity of cleaning the reactor between charges is eliminated". I perceive this to be merely an advantage of the invention and not an essential feature as submitted by the opponent. On this point, I consider that claim 6 is fairly based.

The terms "low gel content" in claims 1 and 6 and "gel content is 10 or less" in claim 5 are potentially indefinite. However, I do not agree with the opponent's submission that the scope of the claims is rendered indeterminate by the use of those terms. In my view the aforesaid terms are descriptive of an outcome of the process of the invention rather than characteristic of the invention itself which is defined in terms of the steps and components of a process.

It is true, as pointed out by the opponent, that the dispersants used in Example 2 are characterised in general rather than specific terms. However, I consider this to be of little consequence since it is clear from the examples how the invention is to be carried out.

Prior Publication

The basic test for anticipation is set out in Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228, at page 235:

"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."

It follows from the reverse infringement test that to constitute an anticipation, a prior document must disclose all of the essential features of the invention as claimed (Nicaro Holdings v Martin Engineering 16 IPR 545, and Catnic Components Ltd v Hill and Smith Ltd [1982] RPC 183).

I consider the essential features of the invention as claimed in claim 1 to be as follows:

A process for producing a vinyl chloride type resin, which includes the steps of:

(A) adding at least one vinyl chloride type monomer to a reaction vessel coated with an aromatic inhibitor polymer build-up compound; and

(B) adding to said vessel an effective amount of a 70 to 98 mole percent hydrolysed primary dispersant; and

(C) adding an effective amount of a 10 to 60 mole per cent hydrolysed secondary dispersant which contains 5% by weight or less of an organic solvent; and

(D) polymerising the monomer.

I note that independent claim 1 (but not independent claim 6) includes the feature "under ... conditions free of cleaning said reaction vessel." I consider that this feature is not essential because it does not materially contribute to the way in which the invention works.

In submitting that the invention was prior published, the opponent relied on the Encyclopedia of PVC, 2nd Edition (supra). I am satisfied that evidence served by the opponent establishes that this publication was available to the public in Australia prior to the priority date.

The Encyclopedia of PVC, 2nd Edition discloses coating of a reactor with an aromatic inhibitor polymer build-up compound and then polymerising vinyl chloride in that reactor in the presence of a primary dispersant of the type defined for use in the present invention. Also disclosed is the polymerisation of vinyl chloride in the presence of a combination of primary and secondary dispersants. However, the citation does not disclose the combination of the feature of polymerising a vinyl chloride type monomer in the presence of a secondary dispersant with the feature of the reactor being coated with an inhibitor polymer build-up compound. Thus, the citation does not disclose the combination of essential features which characterise the invention.

I find that the invention is not anticipated by the disclosures of the Encyclopedia of PVC, 2nd Edition. 

Furthermore, whereas the other prior art documents served by the opponent variously disclose individual features of the present invention, none disclose the combination of essential features which characterises the invention of the application in suit.

Obviousness

Obviousness considerations under the 1952 Act involve a determination of the common general knowledge in the art in Australia at the priority date of the claims:

"... 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."

per Aicken J in The Wellcome Foundation v VR Laboratories (1981) 55 ALJR at 251.

To establish obviousness where a combination invention is involved it must be shown that each of the integers that makes up that combination is common general knowledge in the field in question, and that it would have been obvious to a non-inventive skilled worker in the field to not only select the separate integers which make up that combination, but also to select the particular combination of those integers in question (see Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd 144 CLR 253). The notion of common general knowledge is said to involve that which is known by those in the relevant field and forms the background knowledge which is available to all in the field.

The invention of 606073 lies in the art, well established at the priority date, of making PVC type resins by suspension polymerisation.

It is asserted by declarant Harris, and not disputed by declarant Fattlar, that the following were relevant common general knowledge in the art in Australia at the priority date:

-  The use of a primary dispersant of the type defined for use in the invention, in combination with coating of the reactor with an inhibitor of the type defined for use in the invention, was common practice in the art (disclosed in standard reference works in the art such as the Encyclopedia of PVC, 2nd Edition);

-  The use of a primary dispersant of the type defined for use in the invention in combination with a secondary dispersant (disclosed in e.g. the Encyclopedia of PVC, 2nd Edition);

There is nothing before me to suggest that there would have been any reason for departing from the common practice of coating the inner surfaces of the reactor with inhibitor when a secondary dispersant was to be used as well as a primary dispersant. I therefore conclude that it was obvious to combine the feature of using a reactor coated with inhibitor and the feature of using a secondary dispersant as well as a primary dispersant. I find some support for this conclusion in the fact that both the specification of 606073 and Fattlar's declaration indicate that the problem to be overcome by the invention was concerned with a reaction system incorporating a combination of an inhibitor coated reactor, a primary dispersant and a secondary dispersant.

That problem was that in order to produce PVC having certain desired properties, it was considered necessary to employ a secondary dispersant of a type which initially was only available with a high methanol content and that when that secondary dispersant was used polymer build-up occurred on the walls of the reactor. Further problems associated with that process which I consider would have been evident, would have been that there were materials handling problems associated with using a high methanol containing material and that a substance (methanol) was being incorporated unnecessarily and potentially deleteriously to the reaction mixture.

It is further asserted by declarant Harris, and not disputed by declarant Fattlar, that the following were relevant common general knowledge in the art in Australia at the priority date:

- Secondary dispersants of the type defined for use in the invention (at page 12 of the specification of 606073 it is stated that Alcotex 55/002H is a commercial example of such a material. Evidence served by ICI establishes that they purchased Alcotex 55/002H in Australia before the priority date);

- Methanol is toxic, inflammable and a solvent for a wide range of organic materials.

From these items of common general knowledge I conclude that:

(i) other matters being equal, it would always be preferable in a process to employ a component which had a low rather than a high methanol content because the latter would involve higher safety precautions costs during transit, storage and handling.

(ii) Including an unnecessary but toxic ingredient such as methanol in a reaction mixture could potentially be detrimental to the progress of the reaction and/or the properties of the product.

(iii) Because of its solvent properties it would be likely that a significant quantity of methanol, introduced with a secondary dispersant, would dissolve an aromatic inhibitor compound from the walls of a reactor (I note here that in the paragraph bridging pages 7 and 8 of the specification of 606073 it is said that methanol may be used as a solvent for the inhibitor when applying coats of the inhibitor to the inner surfaces of the reactor).

I consider that the common general knowledge teaches towards using a low methanol rather than a high methanol containing secondary dispersant of otherwise equivalent specification, and that the person skilled in the art would have considered that using a low methanol secondary dispersant in the process would be worth trying as a solution to the problems which the claimed invention solves.

Therefore I conclude that claims 1 and 6 fail for obviousness. No significant submissions were made about the dependant claims. These claims define preferred aspects or add some minor matters. By the same reasoning these claims are also obvious.

Manner of New Manufacture

The opponent's submissions under this ground assert mere substitution of one known secondary dispersant for another in a known process. However, I have already found that it was not a known process for a reactor coated with inhibitor to be used with a primary dispersant and a secondary dispersant.

I find that the opponent has not established lack of manner of new manufacture.

Prior Use

The standard of proof required to establish prior use was dealt with by the UK Appeal Tribunal in Seiller's Application [1970] RPC 103, where at 106 Graham J. stated:

"In my judgement it is necessary that proof of prior user in opposition cases should be very clear. Normally in the absence of cross-examination, this will involve corroboration of a mere statement as to recollection in a declaration, particularly where the time interval involved is considerable. Such corroboration is often best found in documents contemporary with the fact to be proved. Each case, however, must be considered on its own facts and I say expressly that I am not attempting to lay down any rule as to what is or is not sufficient in any given case."

These comments were approved by the UK Court of Appeal in Dunlop Holdings Limited's Application [1979] RPC 523 at 548.

Even though Graham J. stated that he was not attempting to lay down any rule, I think that his comments on the necessity of corroboration by documents contemporary with the facts to be proved are applicable to the present circumstances.

The standard of proof required is the civil standard, that is the balance of probabilities as set out for example by the Court of Appeal in Dunlop Holdings Application (supra), in which Buckley L.J., in referring to the UK Patents Act 1949, stated:

"As to the standard of proof, there is nothing in the statute to suggest that any standard different from the normal standard of proof required in civil litigation - that is to say, the balance of probability - should be adopted. But that standard is not an absolute standard. The nature of the issue may affect the kind and the cogency of the evidence necessary to bring the scales down on one side or the other. If something is inherently improbable, more weighty evidence is required to establish that it probably occurred than if it were inherently probable."

The standard of proof is also referred to in E.I. Dupont de Nemours and Company (Holland's) Application [1971] RPC 7 at 21 where Mr Justice Graham said:

"The matter is, in my view, sometimes different if the question to be resolved is one of pure fact such as may, for example, arise in cases of prior user. Then if satisfied that the evidence has dealt with the matter comprehensively, so that the tribunal feels it is in a position to come to a correct answer on the question of fact, there seems no reason why it should not resolve the conflict and, in my judgement, is in a proper case under the duty of doing so, and in so doing should act upon the normal principles of proof in civil actions."

In the present case, where the alleged prior use of the process and the relevant facts concerning it appear to be within the knowledge of the opponent, the onus is clearly on the opponent to establish that, on the balance of probabilities, prior user has taken place.

I am satisfied that the invoices exhibited to the Harris declarations establish that before the priority date , ICI purchased in Australia an aromatic inhibitor (build-up suppressant) of the type defined for use in the invention, a primary dispersant of the type defined for use in the invention and a secondary dispersant of the type defined for use in the invention. ICI were thus in a position whereby they could have practised the invention before the priority date.

Harris declares that his company (ICI) commenced use of Alcotex 55/002H as secondary dispersing agent in their PVC manufacture in 1985. Harris refers to Exhibit DNH-9 to his third declaration, which is a copy of a document dated 16/12/85. He declares that this is a recipe for PVC manufacture which was used by ICI at its Laverton plant from December 1985 to May 1986. Harris declares that in this recipe the term "BUS" refers to BUS B79 (an inhibitor of the type defined for use in the invention), the terms "Alcotex" and "Altx" refer to "Alcotex 72.5" (a primary dispersant of the type defined for use in the invention), and the term "Alcotex 55" refers to "Alcotex 55/002H" (a secondary dispersant of the type defined for use in the invention).

Although the corroborative evidence is not absolutely conclusive, it is my view that the balance of probabilities lies in favour of the assertion by the opponent that the process of the invention was used by the opponent before the priority date.

I turn now to the issue of whether the prior use was secret use. Referring to copies of PVC sales information exhibited to his third declaration Harris declares that it is "highly likely" that PVC made by ICI by the process of the invention was sold in Australia before the priority date. In Bristol Myers (Johnston's) Application (supra) it was held that sale of a new compound, even though the public would not have been able to detect what it was, constituted prior use by the public of that compound. In the present case, however, the product sold to the public was already known and such sale did not entail entry to the public domain of the process whereby it was made.

In Wykmanshytte's Application at [1961] RPC 180 it was held that when a person makes something within the privacy of a factory, with employees who are under the normal legal duty to their employer, he is not acting publicly, and that such use is not public use. As far as I am aware access to chemical plants or factories is not normally available to the public and the employees in such facilities would be under obligations of confidentiality to their employer. The opponent has not provided any evidence to show that before the priority date any member of the public gained, or was likely to have gained, knowledge of the invention from any prior use of the process of the invention.

In my view the opponent has failed to establish non-secret prior use.

Conclusion

I have decided that all of the claims of the application are obvious. Although I am unable to identify anything disclosed in the specification that could form the subject of a valid claim, I nevertheless allow the applicant 60 days from the date of this decision in which to propose amendments directed toward overcoming my findings. Otherwise, subject to any appeal, I will refuse the application.

Costs

As the opposition has been successful, and there are no special circumstances, I award costs against the applicant.

Alan Moore
Delegate of the Commissioner of Patents

Patent attorneys for the applicant  :  Griffith Hack & Co.,Melbourne.

Patent attorneys for the opponent   :  Davies Collison Cave, Melbourne.