Colgate-Palmolive Company v Westone Products Limited

[1998] APO 69

OFFICIAL NOTICE

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Application  :          No. 664182 in the name of Colgate-Palmolive Company

Title:          Dental Floss

Action: Opposition under section 59 of the Patents Act 1990 by Westone Products Limited.

Decision:          Issued                 .

Abstract

Application for a patent of addition for dental cleaning floss of expanded PTFE with a coating of a non-microcrystalline wax. The present application can proceed as a patent of addition to a parent directed to similar floss with a microcrystalline wax coating because it appears to reflect the discovery of the broadest aspect of the invention (Hughes Tool Company v. Ingersoll-Rand Co. Ltd. [1977] FSR 406) and the invention claimed is not disclosed in the parent.

With regard to Section 40 the best method of performance is clearly the embodiments using microcrystalline wax as claimed in the parent ("the main invention") and the fact that the "additional" claims a less-preferred embodiment with less specific description does not detract from this. That is merely to say that the disclosure of the present application is sufficient to justify the effective broadening in scope of the parent. (American Cyanamid Company v Ethicon Limited, (1979) RPC 215)

The grounds of opposition in relation to section 40, novelty, obviousness and manner of manufacture were not made out. Opposition dismissed.

PATENTS ACT 1990

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Re:Patent Application No. 664182 by Colgate-Palmolive Company and opposition under section 59 of the Patents Act 1990 by Westone Products Limited.

background

Patent application 664182 was filed by Colgate-Palmolive Company (Colgate) on 25 June 1992 claiming priority from US patent application 7/729834 filed on 11 July 1991. During examination the request was amended to be for a patent of addition to patent 611544 and the application was advertised accepted on 9 November 1995.

Westone Products Limited (Westone) filed a notice of opposition on 9 February 1996 and served on Colgate the Statement of Grounds and Particulars on 9 May. Westone sought a number of amendments to the Statement, the last of which was refused by the Delegate in a decision issued on 23 May 1997. The evidentiary stages were completed on 25 May 1998.

The matter came to a hearing in Sydney on 21 October 1998. Colgate was represented by Dr W. J. Pickering, patent attorney of F B Rice & Co, Sydney. Westone relied on written submissions made on its behalf by Mr M Caine, patent attorney of Davies Collison Cave, Melbourne.

Specification

The application relates to dental flosses produced from expanded polytetrafluoroethylene (PTFE) either in single or multiple strands. The specification indicates that users prefer floss that readily passes between their teeth and doesn't require such force that the floss snaps against gum surfaces. To achieve this in the prior art, wax or other lubricants are used as a coating to reduce the coefficient of friction (COF) of the floss strands. PTFE strands on the other hand have a very low COF but because of this they are difficult to handle and the invention proposes that a coating be applied to increase their COF.

Under the heading "Summary of the Invention" the specification indicates that the strands are expanded PTFE produced under specified conditions and that the coating is preferably a microcrystalline wax. The wax coating tends to be removed when the strand is pulled between the teeth exposing the low friction PTFE and hence facilitating use.  Suitable waxes are discussed particularly on pages 13 to 15 and the desired properties include a melting point above 50°C and the wax being plastic and pliable at room temperature (»25°C) rather than brittle. Again microcrystalline waxes are preferred but other substances are not excluded and I note the last paragraph at page 12 which states that:

"The friction coating can be any substance that will adhere to the surface of the expanded polytetrafluoroethylene and which will increase the coefficient of friction of the expanded polytetrafluoroethylene surface to 0.08 or greater."

After indicating that waxes and polyvinylalcohol adhere to expanded PTFE and restating the objective of increasing the coefficient of friction, the description at page 13 says:

"In this regard waxes are effective. A variety of waxes can be used. This includes naturally occurring and synthetic waxes. Petroleum derived waxes, such as paraffin and microcrystalline waxes, can be used."

The independent claims read as follows:

"1.       A dental cleaning floss comprising at least one polytetrafluoroethylene strand that has been expanded by stretching at an elevated temperature, said floss having a coating of a non-microcrystalline wax, wherein said dental floss has a denier of 500 to 1500 and a coefficient of friction of above 0.08 and wherein said non-microcrystalline wax has a melting point of at least 50°C and is not brittle at about 25°C."

"8.       A dental cleaning floss comprising at thread formed from a plurality of polytetrafluoroethylene strands that have been expanded by stretching at an elevated temperature, said floss including a non-microcrystalline wax, wherein said dental floss has a denier of 500 to 1500 and a coefficient of friction of above 0.08 and wherein said non-microcrystalline wax has a melting point of at least 50°C and is not brittle at about 25°C."

Decision

Patent of Addition status

While it is not a ground of opposition, the status of this application under Chapter 7 has implications for the opponent's case in relation to inventive step with the specification of the patent for the main invention, 611544 (the "parent"), being published on 5 October 1998 well before the earliest possible priority date for the present application. A patent of addition may be granted for "an improvement in, or modification of, the main invention" and from Elliott Brothers (London) Ltd.'s Application, (1967) RPC 1:

"The meaning of the words "modification" and "improvement" is clear enough. A modification is an alteration which does not involve a radical transformation and an improvement is a variation, by addition, omission or alteration, to secure a better performance whilst retaining some characteristic part."

Lloyd-Jacob. J in his decision also indicated that "the consideration given must take into account the novelty of the Manner of Manufacture to which the patent applications are directed" or in other words, the proper basis for determining if an application for a patent of addition is an improvement in or modification of the main invention is the comparison between the novel contribution which each specification made to the art.

Westone's argument is that the present application fails that test because the invention now claimed is disclosed in the parent. Claim 1 of the parent patent reads:

"1.       A dental cleaning floss comprising a multiplicity of filaments of Expanded PTFE, having a tensile strength of at least 68,950 kPa and a polymeric matrix strength of at least 689,600 kPa and a coating adhering thereon of microcrystalline wax, said floss having a coefficient of friction of above 0.08."

The novel contribution apparent from the description is the use of a microcrystalline wax (MCW) in combination with expanded PTFE to increase its COF to improve handling characteristics. The MCW is said to "surprisingly" adhere to the PTFE and also to be "capable of carrying a wide variety of actives and agents associated with oral care". I do not find that the parent specification suggests any other substance is suitable as a coating or that non-microcrystalline waxes as defined in the claims have been tried and rejected.

On the other hand the present specification indicates that while coatings of MCW are preferable, other materials that will adhere to expanded PTFE are also suitable. I note the original claims referred to "said floss having a coating of at least one material capable of increasing the coefficient of friction" and it appears that the selection in the amended claims of non-microcrystalline waxes is merely to claim around the parent. I do not believe this is impermissible and while the "novel contribution" here is not apparently an improvement over the main invention it can be characterised as a modification. I note in this regard the decision of Graham J in Hughes Tool Company v. Ingersoll-Rand Co. Ltd. [1977] FSR 406, who in referring to section 26 of the UK Patents Act 1949, stated at 419:

"There is, however, legally no reason why, though its name may suggest the contrary, a patent of addition should be more limited in scope than its parent.

The broadest aspect of an invention is not necessarily discovered until after the first application for the original invention, i.e. the parent application, has been made.  There is nothing in section 26, governing patents of addition, which imposes any such limitation.  The section, in fact, makes it clear that though a patent of addition must be in respect of a modification or improvement in an earlier invention, the main effects are to give the patent of addition the same expiry date as that of the main patent, to remit renewal fees in respect of it, and to protect it from being attacked for obviousness on the basis of the main patent."

Hence I see the present case as being a later "discovery" of the "broadest aspect of the invention" which by the novelty requirement has been reduced to a claim specifying non-microcrystalline wax.

Section 40

Westone's main complaint is that the specification fails to fully describe the invention including the best method known to the applicant of performing the invention. They point to the broad nature of the term "non-microcrystalline" and the lack of specific examples.

In relation to "non-microcrystalline" I believe the term is quite clear and each of the declarants have been able to ascribe a reasonable meaning to it, eg "all other waxes, because they cannot be defined as "microcrystalline" " per Gillings at paragraph 16. It is true that examples of non- microcrystalline waxes have not been given and the general description is scant but the specification does in fact limit the selection of waxes to those having characteristics which make them suitable for the covering of PTFE as a dental floss. I note particularly Page 13.

Sufficiency is also a question of fact (Universal Oil Products Co. v Monsanto Co., (1973) 46 ALJR 658) and I take Dr Pickering's point that none of the opponent's declarants have indicated that the information given is so inadequate that a skilled addressee cannot put the invention into practice. On the contrary the evidence suggests that the applications of waxes to floss material is well understood and I note also on this point that a specification is not insufficient merely because it requires the person skilled in the art to apply their ordinary knowledge and experience to put the invention into effect, even if this requires an element of "trial and error" or experimentation (British Ore v Minerals Separation 26 RPC 124 at 139).

On the requirement for the best method of performance it should be remembered that the intent of the legislation is to prevent a patentee from withholding "something novel and not previously published" (American Cyanamid Company v Ethicon Limited, (1979) RPC 215) and relates to the consideration given to the public for the patent rights granted. A patent of addition is not an independent grant but can have the effect of a limited extension to the scope of the parent and I believe it is reasonable to consider the specification in this light. Hence the best method of performance is clearly the embodiments using microcrystalline wax as claimed in the parent ("the main invention") and the fact that the "additional" claims a less-preferred embodiment with less specific description does not detract from this. That is merely to say that I find the disclosure of the present application is sufficient to justify the effective broadening in scope of the parent.

Following on from the above I also find the claims fairly based on the matter described in the specification.

Novelty

The basic test for anticipation and lack of novelty is the "reverse infringement" test - see General Tire & Rubber Co. v. Firestone Tyre & Rubber Co. Limited (1972) RPC 457 and Meyers Taylor Pty. Ltd. v. Vicarr Industries Ltd. (1977) 137 C.L.R. 228 at 235. In applying this test I must ascertain whether each and every one of the essential features of the claimed invention are provided by the prior disclosure (Rodi Wienenberger AG v Henry Showell Ltd. [1969] RPC 367, Flour Oxidising Co. Ltd. v Carr & Co. Ltd. (1908) 25 RPC 428).

From the discussion above it should be clear that I do not regard the parent patent as disclosing the invention now claimed. However I should add that while Westone point particularly to the passage "amongst different waxes, microcrystalline wax (MCW) …" at page 7 of the parent as indicating the floss within the present claims was made by Colgate, this suggestion, if one could even go that far, falls well short of "clear and unmistakeable directions to do what the patentee has claimed to have invented" (General Tire & Rubber Co. v Firestone Tyre and Rubber Co Ltd., (1972) RPC 457).

The other citations which appeared to be relied upon are EP 423541 and AU 652015. EP 423541 is Colgate's own patent specification and relates particularly to the coating of PTFE with adjuvants such as medicants and flavourants. The adjuvants are mixed in a emulsion of polyvinyl alcohol and polyethylene glycol which is used to coat the PTFE surface. Polyethylene glycol 4000 mentioned in the specification is apparently a waxy substance but there is some unresolved uncertainty as to whether when mixed with PVA it forms a non-microcrystalline wax coating as claimed. Ultimately however I believe the opponent's case fails because there is no disclosure of 500 to 1500 denier, a COF above 0.08 or other required characteristics of the wax, all of which appear to be essential features of the claimed invention.

AU 652015 is the opponent's own patent and was published after the filing date of the present application. It nevertheless may contain information that could be the subject of a claim with earlier priority date per paragraph (b) under "prior art base" in Schedule 1 to the Act and I take it from Dr Pickering's submissions that an earlier priority date for the relevant information in this citation was not contested.

The specification of this citation is directed to two aspects being a dental floss comprising "substantially non-expanded PTFE" coated with wax, preferably beeswax, and also a method of making floss using a lick roller to apply wax coatings to PTFE ribbons. Page 3 indicates that the method is "applicable to both expanded and non-expanded PTFE" and it is clear to me that this amounts to a disclosure of using a lick roller to apply a wax coating to expanded PTFE despite Colgate's rather tortuous argument to the contrary. However there is no disclosure of 500 to 1500 denier or a COF above 0.08 and I am not convinced by Westone's evidence that these features would be considered inherent by a skilled addressee. It is also arguable whether the specification contains clear directions to apply beeswax to expanded PTFE but in either case I do not believe the citation can be said to disclose all the essential features of the claimed invention.

Obviousness

The general test to be applied in determining obviousness is whether the invention would have been obvious to a non-inventive worker equipped with the common general knowledge in the trade as at the priority date (The Wellcome Foundation Limited v. V R Laboratories (Aust) Pty Ltd ( 1980-1981) 148 CLR 262 at 270). It was also stated in the Wellcome case, supra, at 286 that:

"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."

Westone admit that the use of expanded PTFE as dental floss material was not common general knowledge at the claimed priority date. They however rely on the disclosure of EP 423541 under Section 7(3) asserting that it would be obvious for a person skilled in the art, on the basis of that disclosure, to coat the expanded PTFE fibres with a wax that was not microcrystalline. This is based on the disclosure apart from examples 9-12 which can be said to be a publication of the main invention of the parent.

The difficulty with Westone's evidence, including that of Dr Gillings, is that it is suggestive of an ex post facto analysis of the invention under consideration. In particular there is no logical sequence leading from the prior art to the invention claimed and in this regard it is not appropriate to approach the question stated in Wellcome by starting with the solution and asserting that it would be achieved as a by-product of solving a different problem. This is what appears to be behind the suggestion that coating PTFE for reasons other than altering frictional characteristics, eg to incorporate flavourants, would result in a floss falling within the claims.

The problem addressed by the present invention is essentially that conventional prior art flosses are difficult to pull between the user's teeth even with coatings applied. EP 423541 in disclosing PTFE floss may well have been seen as a part solution. However, there is nothing to suggest that the skilled addressee would have recognised that there was a difficulty with handling characteristics or that these could be corrected by adding a wax coating to increase the COF above 0.08. The European specification in this regard deals with adjuvants and does not suggest the use of a coating to increase COF. Also the common general knowledge appears to have considered wax coatings only as a lubricant and it would be surprising if the skilled person would have immediately thought of using a wax coating to increase COF. Mr Blass' second declaration at para. 7 seems to contradict this although his view is opposite to Dr Gillings and Colgate's declarant Dr Tyas who both best reflect the state of knowledge in Australia at the claimed priority date. Dr Gillings does say that coating PTFE with a wax "probably" increases its inherently low COF and that there would be "nothing surprising" in the result of a floss which is easier to grip, but nevertheless slips easily between the teeth, but this far less than saying the result was obvious at the priority date.

Consequently I do not find that the evidence conclusively shows that the claimed invention is lacking an inventive step.

Manner of Manufacture

Westone submit that the claimed invention is nothing more than the new use of a known material or that it is a collocation of known materials. In relation to "new use" I was referred particularly to the decision of the High Court in N V Philips Gloeilampenfabrieken v Mirabella ( 1995) 132 ALR 117 which established that the phrase "manner of manufacture" in section 18 incorporated the same subject matter considerations as encompassed by the words "manner of new manufacture" under the 1952 Act.

In The Commissioner of Patents v Microcell 102 CLR 232 at 251 the court found:

"We have in truth nothing but a claim for the use of a known material in the manufacture of known articles for the purposes of which its known properties make the 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."

In relation to this principle Morton J. in Re L & G's Application 58 RPC 23 referred to a number of circumstances that would tend toward a finding of patentability:

"1)  where a change or variation of the construction of the apparatus is rendered necessary by the use of a particular kind of material not previously used for that purpose;

2)   where the use for a particular apparatus of a known material not previously used for that purpose is due to a hitherto unknown or unsuspected property of the material; or

3)   where the adaptation of the known material to the particular piece of apparatus leads to a new departure in the technique of the production of the apparatus."

The submission is that the claimed floss is substantially the same as conventional waxed floss except that the fibres are now made of expanded PTFE without "substantial change in structure to the floss or substantial change in the manufacturing process". It is also said that under this ground it is not necessary to establish that knowledge of the properties of the material was possessed by those skilled in the art at the priority date.

I however find it is somewhat simplistic to characterise the invention as “nothing but” a new use of expanded PTFE and I believe the first of Morton’s exclusions can be said to apply. Expanded PTFE has a COF far below that of conventional flosses and rather than apply waxes to the fibre to reduce friction the present invention requires, for satisfactory use, the addition of wax to raise the COF above 0.08. This is a variation of the construction rendered necessary by the use of expanded PTFE.

Hence the claimed invention does not appear to lack patentable subject matter.

Conclusion

I have found that none of the grounds of opposition have been made out and consequently I dismiss the opposition.

costs

There is nothing in the present case that suggests costs should not follow the event. Consequently I award costs against Westone Products Limited.

Philip Spann
Delegate of the Commissioner of Patents

Patent attorneys for the applicant  :    F B Rice & Co, Sydney

Patent attorneys for the opponent  :    Davies Collison Cave, Melbourne