Application of Slocombe, Patent Appeal No. 74-603.

• Citation: 510 F.2d 1398
• Decision Date: 20 February 1975
• Docket Number: Patent Appeal No. 74-603.
• Court: United States Court of Customs and Patent Appeals
• Parties: Application of Robert J. SLOCOMBE.

510 F.2d 1398

Application of Robert J. SLOCOMBE.

Patent Appeal No. 74-603.

United States Court of Customs and Patent Appeals.

February 20, 1975.

Robert W. Furlong, Fish & Richardson, Boston, Mass., attorney of record for appellant. Ernest K. Bean, Assts. Gen. Counsel, Akron, Ohio, of counsel.

Joseph F. Nakamura, Washington, D. C., for the Commissioner of Patents. Fred E. McKelvey, Washington, D. C., of counsel.

Before MARKEY, Chief Judge, RICH, BALDWIN, LANE, Associate Judges, and PHILIP NICHOLS, Associate Judge, United States Court of Claims.

BALDWIN, Judge.

This is an appeal from the decision of the Patent Office Board of Appeals affirming the examiner's rejection of claims 27 and 28 of appellant's application¹ entitled "Low Temperature Synthetic Rubber and Method of Making Same." We reverse.

The Invention

Appellant claims a method or process for producing a vulcanizable polybutadiene disclosed as having improved flexibility at low temperatures. The claims on appeal are as follows:

27. A method for polymerizing 1,3-butadiene which comprises contacting said 1,3-butadiene with a catalyst consisting essentially of (a) a compound corresponding to the formula R3A1, wherein R is alkyl radical having 2 to 4 carbon atoms and (b) titanium tetraiodide.

28. A process for producing rubbery vulcanizable polybutadiene which is characterized by improved flexibility at low temperatures, which process comprises polymerizing butadiene-1,3 in an inert hydrocarbon medium in the presence of a catalyst resulting from the interaction in said medium of (a) a trialkyl aluminum of the formula R3A1 wherein R is an alkyl radical containing 2 to 8 carbon atoms and (b) titanium tetraiodide, the mo1 ratio of aluminum to titanium being from 0.3 to 1 to 15 to 1.

Prosecution History

Appellant's application, as originally filed on April 18, 1955, contained 13 claims directed toward methods of making polybutadiene, polyisoprene copolymers of butadiene and isoprene and the products polybutadiene and polyisoprene prepared by polymerizing their respective monomers in the presence of specific catalysts. The catalysts were broadly recited as the interaction product of (1) an aluminum compound of the formula R2A1X, wherein R is an alkyl, cycloalkyl, or acyl radical, and, X a hydrogen, halogen, alkyl, cycloalkyl, or aryl radial, with (2) a metal halide selected from the group consisting of the chlorides, bromides and iodides of titanium and zirconium.

On October 9, 1961, two interferences, Nos. 92,258 and 92,259 were declared; appellant being senior party in the former and junior party in the latter. The counts were process claims involving, respectively, polymerization of butadiene with the interaction product of an aluminum trialkyl and titanium tetrachloride, and polymerization of isoprene with the interaction product from the same reactants, and also requiring, in each case, specific and different molar ratios of titanium to aluminum.

Priority was awarded against appellant in both interferences. The winning party in Interference No. 92,259 obtained U.S. Patent No. 3,114,743 (Horne) while the count of Interference No. 92,258 became claim 5 of U.S. Patent No. 3,657,209 (Carlson et al.); both of which will be further discussed, infra.

Subsequent to a decision by the Patent Office Board of Appeals on April 8, 1964, holding that appellant's specification supported process claims directed to polymerization of butadiene and employing as a catalyst the interaction products of AIR3 and TiI4,² wherein R is an alkyl radical containing 2 to 8 carbon atoms, an interference³ was declared with instant claim 27 as the count. Appellant was awarded priority as to claim 27. The examiner rejected both claims 27 and 28 on prior art.

                References
                  Horne                3,114,743        December 17, 1963
                                                          (filed December 2, 1954)
                  Robinson et al.      3,118,864        January 21, 1964
                                                          (filed November 22, 1954)
                  Crawford et al.        215,043        November 1, 1956
                      (Australia)
                  Stewart et al.         627,741        September 19, 1961
                      (Canada)
                  Short et al., Rubber Chemistry and Technology
                           Vol. 30 (1957), pages 1118-1141
                  Short et al., Rubber Chemistry and Technology
                           Vol. 32 (1959), pages 614-627
                  Moyer et al., Journal of Polymer Science
                           Part A, Vol. 3 (1965), pages 217-229.
                

Additional prior art consists of claim 5 of U.S. Patent No. 3,657,209 (Carlson et al.), lost by appellant in Interference No. 92,258. Claim 5 of Carlson et al. is as follows:

The method which comprises polymerizing a monomeric material consisting essentially of monomeric butadiene-1,3 in an inert liquid hydrocarbon medium in the presence of a polymerization catalyst prepared by mixing (a) titanium tetrachloride with (b) a trialkyl aluminum compound, the proportions of (a) and (b) being such as to provide a molar ratio of titanium to aluminum of about 1.5 to 1.0 to 3.0 to 1.0.

U.S. Patent No. 3,114,743 (hereinafter Horne) discloses the preparation of polyisoprene by the polymerization of the monomer isoprene. The catalyst employed is the reaction product of equimolar proportions of (1) a compound containing a heavy metal occurring in the 4th to 6th positions of the long periods of the periodic table and (2) an organoaluminum compound. Viewed in a light most favorable to the Patent Office, the catalyst employed by Horne is the reaction product of a titanium halide, the chloride being most preferred, and an aluminum trialkyl.

U.S. Patent No. 3,118,864 (hereinafter Robinson et al.) discloses the preparation of homopolymers and copolymers of conjugated alkadienes such as butadiene, isoprene and chloroprene. The catalyst employed in carrying out the polymerization is the reaction product of titanium tetrachloride and a lithium-aluminum tetraalkyl.

The Rejection

The board affirmed the examiner's rejection of claims 27 and 28 as being unpatentable (35 U.S.C. § 103) over Horne in view of Robinson et al. and over the count of Interference No. 92,258 (Claim 5, of Carlson et al.), in view of Robinson et al. or Horne. It was the board's position that

Robinson et al. disclose the similarity of butadiene and its homologue, isoprene, in a polymerization closely related to that herein claimed. In view of this disclosure, we agree with the Examiner that it would be obvious to substitute butadiene for the isoprene in the process of Horne, thus to anticipate appellant's claimed process, noting particularly the teaching in Horne (sentence bridging columns 2 and 3) of iodides as substitutes for chlorides of metals such as titanium in the catalyst combination.

The board found it unnecessary to specifically commit upon the rejection of claims 27 and 28 as being unpatentable (35 U.S.C. § 103) over claim 5 of Carlson et al. in view of Robinson et al. or Horne. We thus look to the examiner's answer to find the specifics of this rejection. It was the examiner's position that

the count . . . is directed to polymerizing butadiene with a Ti C14-A1R3 (R is alkyl) catalyst using a Ti/A1 ratio of 1.5/1 to 3/1 (A1/Ti of 0.67/1 to 0.33/1). Since Horne teaches the equivalence of the Ti I4-A1R3 and Ti C14-A1R3 catalysts when polymerizing another conjugated diolefin, i. e., isoprene, a homolog of butadiene, it would be obvious to use Ti I4 in place of Ti C14 to polymerize butadiene as recited by the count. From the disclosure of Robinson et al, one would expect either butadiene or isoprene to form solid useful polymers using a titanium tetrahalide-A1R3 catalysts in view of its generic teaching of organometallic reducing agents.

In response to these rejections, appellant submitted to the Patent Office three Rules 132 affidavits. The first, by Minchak, reports the Gehman Freeze Point of various polybutadienes and polyisoprenes, made in accordance with the prior art and the claimed process. Although the affidavit showed superior low temperature properties for butadienes prepared according to the claimed process as compared to polybutadienes of Robinson et al. or the count of Interference No. 92,258 or the polyisoprene of Horne,⁴ the examiner refused to consider the results on two grounds:

There is no basis in this specification for any differences of any kind including low temperature properties between polybutadienes or polyisoprenes produced with a TiI4-A1R3 catalyst as compared to a TiC14-AIR3 catalyst. This specification, as far as the properties of the polybutadienes and polyisoprenes are concerned, teaches the equivalence of the catalysts formed from titanuem sic tetrahalides and a wide variety of organoaluminum compounds . . ..

* * * * * *

With the above in mind it is also believed that the affidavit provides insufficient evidence that the low temperature properties of polybutadienes produced within the bounds of claims 27 and 28 will inherently have better low temperature properties than those of Robinson et al. The specification does not teach that they do and in view of the difference produced between the two titanium tetrahalides, there is no reasons sic to presume they will. Moreover, it is a fact that the structure of the polybutadiene produced with a TiI4-A1R3 catalyst in dependent upon the A1/Ti ratio, the catalyst concentration and the solvent as shown by Moyer et al. and Stewart et al. The two Short et al. articles show how the properties of the polybutadienes are affected by its structure. The Crawford et al. reference also shows how structure and properties are affected by different Ziegler-type catalysts.

The second affidavit, by Macey, indicates that the Gehman Low Temperature Torsion Test is a measure of the potential use of a rubber at low temperatures, such as might be found in arctic regions. Macey further expressed his opinion that a difference on the order of as little as 10°C in the Gehman temperature has a pronounced influence on the practical...