Appeal No. 2000-1155
Application No. 08/908,655
less than 2 wt.%, and (2) an amine-free chain extender having a
particular formula. This appealed subject matter is adequately
illustrated by independent claim 12 which reads as follows:
12. A reactive composition comprising
(A) an NCO prepolymer based on an aliphatic and/or
cycloaliphatic polyisocyanate and having an
NCO content, based on the aliphatic and/or
cycloaliphatic polyisocyanate, of 2 to 4 wt.%
and a monomeric polyisocyanate
content of less than 2 wt.%,
(B) an amine-free chain extender comprising at
least 50 equivalent percent, relative to
the NCO-reactive groups of the chain extender,
of a compound melting between 50OC and 160oC
and having the formula (I)
HO-X-Y-X-OH (I)
wherein
Y denotes 1,4-, 1,3-, or 1,2-phenylene, and
X denotes methylene or -OCH2CH2- (wherein
the oxygen atom is bonded to group Y),
and
(C) 0 to 20 wt.%, relative to component (A), of one
or more inert organic solvents, wherein the
equivalent ratio of the free NCO groups of
component (A) to the NCO-reactive groups of
component (B) is 0.90 to 1.35.
The reference set forth below is relied upon by the
examiner as evidence of obviousness:
Quay et al. (Quay) 5,175,230 Dec. 29, 1992
2
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