Appeal No. 2001-1986
Application No. 08/719,968
hydrogenated polybutadiene has the same structure as polyethylene.4 Thus, Scheve teaches that the
very structure resulting from the hydrogenation is a useful embodiment of his invention. Although
this finding of fact could be used as part of the basis of a prima facie case of unpatentability of the
claimed subject matter, it is not necessary, as the examiner’s rationale suffices.
Finally, the reactions to make such a prepolymer are the same as those recited in Appellant’s
claim 23, step a: reacting an excess of diisocyanate with diols, and further reacting the resulting
oligomer with hydroxy(meth)acrylates. (Scheve at col. 7, ll. 54–68.) In light of these findings of
fact, which are well-supported by the evidence relied on by the examiner, I hold that a prima facie
case of obviousness of the subject matter of claim 23 over the prior art of record has been made, and
I would affirm the examiner’s rejection of claim 23.
The status of claim 22 and its dependent claims, which limit the recited polymerizable
composition by the phrase “consisting essentially of,” is more problematic. As Appellant pointed
out, Scheve distinguishes his invention from compositions having only urethane prepolymers,
stating that the additional presence of polyester prepolymers results in better solvent resistance and
washout characteristics. (Brief at 5; Scheve at col. 2, ll. 4–8.) The examiner is correct that the
4 More precisely, end-to-end polymerized butadiene, also known as poly(1,4-butadiene). The structure of the
cis-isomer is similar to that of natural rubber, while the structure of the trans-isomer is similar to that of gutta percha.
See the entry from HAWLEY’S CONDENSED CHEMICAL DICTIONARY, 11th ed. at 932 (1987)(entry on polybutadiene),
attached to this decision. The structures of natural rubber and gutta percha differ solely in that pendant methyl (-CH3)
groups take the place of hydrogen in polybutadiene. See Figure 32.4 of ROBERT T. MORRISON & ROBERT N. BOYD,
ORGANIC CHEMISTRY, 3d ed. at 1048 (1973), also attached. Comparison of the structure of polyethylene (HAWLEY’S at
935, also attached to this dissent) with the structure of hydrogenated polybutadiene shows that they consist of a series of
methylene (SCH2S) groups bonded to one another in linear fashion. In a chemically fluent world, these elementary
chemical facts would be sufficiently generally known as to be susceptible of notice, but precedent in our world is to the
contrary, hence these references are made of record. The life of a patent examiner, as much as the life of a patent
solicitor, is a hard one.
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