Appeal 2007-2739
Application 11/106,321
ll. 6-10). Berger states that “[w]ith proper adjustment of the reflux ratio,
there can be achieved continuous cracking of the silylorganocarbamate, and
continuous overhead separation of the silylorganoisocyanate as an overhead
product” (id. at col. 4, ll. 14-17).
Thus, Berger teaches that Pepe’s step of converting the
silylorganocarbamate to the silylorganoisocyanate intermediate can be
alternatively accomplished in the absence of Pepe’s cracking catalysts,
simply by heating the reaction mixture appropriately. One of ordinary skill
making silylisocyanurate according to Pepe’s teachings would therefore
have considered it obvious to leave out Pepe’s cracking catalysts and heat
the silylorganocarbamate in the presence of the trimerization catalysts to
produce the silylorganoisocyanate intermediate, and ultimately the
silylisocyanurate. We therefore agree with the Examiner that claim 1 would
have been prima facie obvious to one of ordinary skill in view of Pepe and
Berger.
Appellants argue that Berger uses a silylorganohalide to produce the
silylorganocarbamate starting material, whereas the “process of the present
invention does not use a sily[l]organohalide, a chemical with specific
characteristics, in conducting the process” (Br. 8). Appellants urge that,
“[m]oreover, combining Berger with Pepe et al. still does not correct the fact
that the process described in Pepe et al. uses aluminum and tin alkoxide,
wherein the claimed process specifically excludes any substantial amount of
aluminum and tin alkoxides as part of the process” (id.).
We do not find this argument persuasive. Claim 1 does not contain
any limitation regarding the method by which the silylorganocarbamate
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