Appeal No. 1997-1997
Application No. 08/263,496
5-7 and 18-22 under § 102 over Carroll. Since Carroll
discloses a prepolymer formed by reacting a polyoxypropylene
polyol with diphenylmethane diisocyanate, and blending the
prepolymer with polymethylene polyphenylene polyisocyanate,
the examiner concludes that "Carroll's composition would be
the same as that of appellant's" (page 3 of Answer). However,
as detailed by appellant, the presently claimed prepolymer is
the chemical reaction product of three components, whereas the
prepolymer of Carroll is the reaction product of only two
components, a polyol and diphenylmethane diisocyanate, which
reaction product is then physically admixed with a
polymethylene polyphenylene polyisocyanate composition.
Carroll expressly teaches that the diphenylmethane
diisocyanate used in making the prepolymer is in pure form,
i.e., it is substantially free from polymethylene polyphenyl
polyisocyanates (column 2, lines 10-16 and column 3, lines 10-
12). We also invite attention to Carroll's disclosure that
"[t]he polyisocyanate compositions of the invention may be
manufactured by mixing appropriate amounts of component A and
component B in any convenient manner" (column 3, lines 38-41,
emphasis added). While the examiner contends that "[d]ue to
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