Appeal No. 94-2414
Application 07/911,504
Although Colin teaches that it is generally accepted that the
surface of a silica gel particle is covered with a monolayer of
silanol groups with an irregular distribution, Colin clearly
teaches that it is necessary to activate or dehydrate the silica
before carrying out monochlorosilane bonding. Compare, for
example, the disclosure of Colin at page 297, first full
paragraph, and Colin’s teaching that a “completely hydroxylated
silica” has been obtained by prior art workers by activating or
dehydrating silica gel on heating at 250E under a vacuum.
Further, we observe appellants’ acknowledgment (specification,
page 11, line 34 to page 12, line 28) that appellants’ drying
step is effected by method known in the art. There is therefore
no reasonable basis to argue, as appellants have, that
appellants’ dry gel having essentially one form of silanol moiety
differs at all from prior art “completely hydroxylated” silica
gels which have been bonded by reaction with an
organochlorosilane.
Where, as here, the prior art organochlorosilane bonded
silica gel appears to be either identical or slightly different
from the organochlorosilane bonded silica gel defined by product-
by-process claims 32 and 34, the burden is on appellant to
establish that the prior art gels do not necessarily or
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