Application of Pike

178 F.2d 949, 37 C.C.P.A. 795
CourtCourt of Customs and Patent Appeals
DecidedDecember 12, 1949
DocketPatent Appeal 5635
StatusPublished

This text of 178 F.2d 949 (Application of Pike) is published on Counsel Stack Legal Research, covering Court of Customs and Patent Appeals primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Application of Pike, 178 F.2d 949, 37 C.C.P.A. 795 (ccpa 1949).

Opinion

O’CONNELL, Judge.

This is an appeal from the decision of the Board of Appeals of the United States Patent Office affirming the rejection by the Primary Examiner of all_of the claims, Nos. 13-15, 17-20, and 22-24,- in appellants’ application for a patent for an alleged invention relating to adhesive compositions containing butadiene copolymers.

Claims 14, 15, and 18 were rejected as being drawn to nonelected species and, therefore, need not be considered here on their merits.

The references are:

Abrams et al. 2,142.039 Dec. 27, 1938
Baehie (German) 705,104 Apr. 17, 1941
Tierney 2,319,959 May 25, 1943
Sóday 2,366,219 . Jan. 2, 1945
Juve, India Rubber World, Vol. 110, No. 1,
April 1944, pp. 51-53.

Claim 22 is illustrative of- the appealed claims. It reads:

“22. A pressure-sensitive adhesive composition including a cohesive elastomer comprising a copolymer of butadiene and styrene and which has an initial shearing viscosity within the range 65 to 140, as measured on a Mooney plastometer at 100° C, and including by weight substantially one part of a compatible tackifying resin for each one to four parts of said cohesive elastomer.” ■

The involved subject matter was succinctly described -by the examiner to the following effect:

*950 “The alleged invention relates to a pressure sensitive adhesive composition made with GR-S [Government Rubber Type S] butadiene-styrene copolymer of Mooney viscosity 65 to 140 at 100° C as the cohesive rubbery component and in addition the conventional plasticizing and resinous tackifying agents.
“Appellants assert that Standard GR-S, a butadiene-styrene copolymer having a Mooney shearing viscosity of 45 to 60, is unsatisfactory as an adhesive if the compounding processes used with natural rubber are followed. The resulting adhesives are asserted to be too soft, and are subject to cold flow and splitting [due to lack of cohesive strength]. By utilizing the higher viscosity adhesive defects are asserted to be avoided.”

The patent to Soday, the principal reference, discloses an adhesive composition adapted to form pressure-sensitive adhesive coatings comprising a -mixture of isoprene resin and rubber dissolved in a suitable liquid vehicle. An object of Soday’s invention is the provision of an adhesive tape comprising a suitable backing, such as a strip of fabric or regenerated cellulose, ■having an adhesive dispersed thereon. The patentee may use as the cohesive elastomer the -rubber-l-ike polymers of butadiene with styrene; and as the tackifying resin, he may preferably use isoprene resin as the only resinous ingredient in the preparation of the adhesives, although he may -also use resin in conjunction with isoprene resin.

The specific examples given by Soday as illustrative of his composition discloses the use of rubber as the cohesive agent, but, in a general disclosure, a number of rubber substitutes are also described, among which is the butadiene-styrene copolymer. “Rubber, in general,” Soday states, “imparts cohesiveness (firmness) to the adhesive, while the isoprene resin imparts tack to the adhesive mixture.” The patentee further stated that milling rubber increases its adhesiveness and decreases its cohesiveness, or body; and that particularly desirable results may be obtained in producing the adhesives “when the proportion of isoprene resin employed amounts to 20% to 80% by weight of the rubber present.”

Sod-ay states also that the incorporation of certain antioxidants or stabilizing agents in the composition is desirable, such as-, for example, phenyl beta naphthylamine. That antioxidant, as well as the resin hereinbefore mentioned, are items which appellants employ in their claimed composition to accomplish the same purpose that Soday had in mind.

The patent to Abrams et al. and the patent to Tierney, auxiliary references, relate to pressure-sensitive adhesive coatings suitable for application to a variety of- -surfaces or base materials, -such as tapes, and other similar articles. Abrams et al. disclose “that legginess is avoided by increased cohesiveness.” Both patents show a conventional requirement in pressure-sensitive adhesives is the utilization of a cohesive elastomer and a tackifying resin, and may include a plasticizer to control tack or adhesion.

The German patent to Bachle discloses an adhesive with a butadiene-styrene copolymer and a tackifying resin or agent. The proportions by weight of the tackifying resin to the cohesive elastomer disclosed in the patent is within the range of proportions defined by the limitation of claim 22.

The article by Juve published in the India Rubber World subsequent to appellants’ filing date was cited by the examiner not as an anticipatory reference but merely as an explanatory discussion of the Mooney viscosity test -and Mooney viscosities with respect to the characteristic properties of natural rubber and various synthetic or ■artificial rubbers. Appellants directed the •attention of the Board of Appeals to the fact that Juve demonstrated that many of the properties of rubber are inherently different from the properties of synthetic -rubbers. The board, in turn, directed attention to the fact that Juve also disclosed the range of the Mooney viscosity of the smoked sheet rubber disclosed by Soday was between 65 and 140.

The issue here involved is described in the following language quoted from the brief for appellants:

“The main question for decision is whether it was invention to 'formulate a *951 pressure-sensitive adhesive with a "high” Mooney viscosity butadiene-styrene copolymer within the critical range 65 to 140 as its cohesive elastomer, when its apparent lack of utility was indicated by the industry’s entirely unsatisfactory experiences with the standard "low” Mooney viscosity butadiene-styrene copolymer - the type normally used as a rubber substitute. (Italics quoted).”

Appellants assert that for years rubber was the cohesive elastomer used in the production of pressure-sensitive adhesives; that when the industry was deprived of rubber during the war and a substitute therefor 'had to be found, they experimented with the GR-S butadiene-styrene copolymer of the higher Mooney viscosity herein-before described and, to their surprise, and contrary to normal expectations, discovered that it produced adhesives capable of passing the Government’s specification of 500 seconds for firmness, whereas Standard GR-S produced poor adhesives having a range of 5 to 30 seconds for firmness; and that the higher Mooney viscosity produced adhesives which not only gave much less trouble from “stringiness” or “legginess” due to a deficiency in cohesiveness but also possessed ageing qualities much better than those of the adhesives made from the rubber which had been used by the industry for many years.

The patent to Soday, like each of the other cited patents, makes no reference to Mooney viscosities and no viscosity ranges are therein given.

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Bluebook (online)
178 F.2d 949, 37 C.C.P.A. 795, Counsel Stack Legal Research, https://law.counselstack.com/opinion/application-of-pike-ccpa-1949.