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                  COMMISSIONER'S DECISION

 

Reissue: Polyolefin Rubbers

 

In the original patent the claims were directed to a polybutadiene resin

mixed with 2-35% filler. In the reissue application the film was extended

to 2-58% filler. However there was never any disclosure of such a broad range,

and the Applicant made a scientifically unsound extrapolation to justify his

new claims. The claims are not adequately supported.

 

Rejection: Affirmed

 

                  **************

 

Patent application 271054 (Class 400-78), was filed on February 4, 1977,

for an invention entitled "Polyolefin Rubbers Reacted With Butadiene

Resins." The inventors are Jon W. Martin et al, assignors to TRW Inc.

The Examiner in charge of the application took a Final Action on Feb. 16,

1978, refusing to allow it to proceed to patent. Applicant has requested

a review, but has not asked for a Hearing.

 

The Applicant wishes to reissue his earlier patent 920733, granted February

6, 1973, for a peroxide cured elastomeric composition useful in corrosive

environments. The composition comprises a polyolefin rubber matrix, a

liquid derived 1,2-polybutadiene resin with a minimum of 84% butadiene in

the vinyl configuration and a filler. In patent 920733 the claims are

restricted to a composition containing 2-35% by weight of filler. Claim 1

recited below is the broadest claim of patent 920733.

 

A peroxide-cured elastomeric composition comprising:

a polyolefin rubber matrix: 40%-94%; a liquid derived 1,2-polybutadiene

resin: 2%-40%; containing a minimum of 84% butadiene units in the

vinyl configuration; and filler: 2%-35%, all percentage parts by

weight.

 

In the reissue application, Applicant wishes to broaden the scope of claim

1 by altering the amount of filler to "at least 2% ... by weight," i.e. up

to a maximum of 58% by weight.

 

The Examiner refused claims 1 to 3,and with them dependent claims 7 to

9 of the reissue application, for being too broad. Firstly, these claims

were held to be broader than the original invention disclosed, which,

the Examiner contended, supports only the range of 2 to 40.48% of filler

by weight. The Examiner conceded that there were grounds for reissuing

to cover the range of 2 to 40.48% by weight of filler. Additionally,

the Examiner maintained that the claims in the reissue application were

too broad "in view of the reissue petition paragraph 3". The relevant

parts of said paragraph 3 of the petition read as follows:

 

(a) The claims are too limited in that they require the

presence of 2 to 35% filler. This is clearly unrealistic,

having regard to the nature of the invention made by the

inventors, and disclosed in the specification. For example,

compound 11 on Page 10 of the patent contains about 40%

alumina filler, in addition to about 3% dicumyl peroxide.

 

(b) There is no claim which covers a filler content of 2

to 58%. If one uses the minimum amounts of the two polymers

disclosed in the specification and claimed in Claim 1 or 3,

totalling 42%, there remains 58% of materials which can be

accounted for as filler.

 

The Examiner maintained that "in a three component system it does not

necessarily follow that the maximum of a given component is calculable

by subtracting the sum of the minima of the other two components from

100%" but, that the operable "maximum" amount of the third component can

be determined only by experiment. Further, the Examiner contended that

the "calculable" maximum asserted by Applicant in the disclosure and

the claims of the reissue application is not supported by the specification

of patent 920,733. The Examiner's rejection is based on the requirements

of Section 50(1) of the Patent Act that the "new patent...be issued to

him for the same invention..."

 

In his response to the Final Action, Applicant argues (relying upon the

decision in Curl Master v Atlas Brush S.C.C. 52 CPR 51) that an

".., imperfect description is sufficient;" and further that the description

"...can fall short..." of that required to support the claims. It should

be noted that in the Curl Master case the patent included a drawing

which formed part of the original specification or description, and that

that drawing provided support for the claims of the reissue application.

By contrast, the figures in patent 920,733 are merely photographs of valve

seats made from the composition claimed, and electron micrographs of the

elastomer made from that composition. These figures do not provide any

support for the breadth of claims in the reissue application, nor does

the remainder of the specification of patent 920733. Thus, Applicant's

argument that refusal of the reissue claims is "contrary to the principles

followed in the Curlmaster decision" is not justified.

 

Furthermore, it is clear from Section 36(1) of the Patent Act that a "high

standard of disclosure" is indeed required, and that such a disclosure in

the specification of the original patent can provide the only basis for the

acceptance of broad claims in a reissue application under Section 50(1)

of the Patent Act. The description in the disclosure of the original

patent may be insufficient but, nevertheless there must be some support

in the specification, albeit in imperfect form.

 

Finally, Applicant argues that the extended range of the filler composition

sought in the reissue application is inferable from the examples provided

in patent 920,733. On the basis of these examples, he states "There is no

logical reason to have taken 35% or even 40.5% as being the maximum amount

of filler." However, this argument is not accepted nor are the reasons

for arriving at such a conclusion.

 

On a careful reading of the entire specification of patent 920,733 it

is clear that there is no support for a composition with a filler con-

centration above 40.48% by weight. Applicant has presented with his

arguments a graph, labelled Fig. I, in support of his contention that

the breadth of the filler concentration is inferable. We believe, however,

that Applicant's arguments using this graph are scientifically and technic-

ally unsound(cf Philip R Bevington Data Reduction and Error Analysis for

the Physical Sciences, McGraw-Hill, 1969). Applicant has plotted tensile

strength v. "% replacement of polybutadiene with filler." However, such

a two-dimensional graph has no meaning technically in a 3 component

system, since it is clear that as the filler concentration increases both the

concentration of the polyolefin and that of the polybutadiene decreases.

 

Further, it is noted that Applicant has plotted the point, tensile strength

= 1900,filler = 40.5% incorrectly.

 

Applicant has then used the results of 3 plotted points to draw a "smooth

curve" without any scientific justification for such a curve. Indeed, if

one also plots the point, tensile strength = 1800, filler = 17% as provided

in Applicant's response (Experiment 3 on page 8 of patent 920,733) it is

clear that there is no justification for the "smooth curve" drawn by

Applicant.

 

Nevertheless, Applicant uses his "smooth curve" to extrapolate the expected

operability of concentrations of filler above 40.5% by weight. It is well

known that it is scientifically unsound to extrapolate in formation based

on a "smooth curve" drawn with such a paucity of experimental information,

especially when the "smooth curve" is derived using the kind of reasoning

advanced by Applicant and also in the absence of experimental information

 between 40.5 and 100% filler. Such a "smooth curve" can only be inferred

 when there is sufficient experimental information to interpolate between

 points, i.e. it is statistically sound. Applicant argues for a hypothetical

 result based on the expected operability of a composition with a concentration

 of filler greater than 40.48% and up to 58% by weight. As such, these

 arguments are not convincing in the absence of clear support for these filler

 concentrations in the specification of patent 920,733 or, alternatively,

 more experimental information in patent 920733 supporting the hypothesis

 advanced in Applicant's response to the Final Action.

 

 We believe the Examiner was justified in refusing the broad claims submitted

 in reissue application 271054 as contrary to Section 50(1) of the Patent Act.

 The disclosure and claims must be restricted to a filler concentration of

 "2 to 40.5% by weight" and application 271054 will be allowable when amended

 in this manner.

 

 G.Asher

 Chairman

 Patent Appeal Board, Canada

 

 I have reviewed the prosecution of this application, and the recommendations

 of the Patent Appeal Board, which I now adopt. The application to reissue

 is refused, but may be amended as proposed by the Board. The Applicant has

 six months in which to make such an amendment, or to take the rejection to

 appeal.

 

  J.H.A. Gariepy                   Agent for Applicant

  Commissioner of Patents          Gowling & Henderson

                                   Box 466, Terminal A

                                   Ottawa, Ont.

 Dated at Hull, Quebec

 this 2nd. day of January, 1980

 You are being directed to the most recent version of the statute which may not be the version considered at the time of the judgment.