Appeal No. 94-2414
Application 07/911,504
quantity of organochlorosilane to bond organochlorosilane to the
dry gel thus forming a bonded silica gel structure. Thus, it is
questionable whether the claim language “having essentially one
form of silanol moiety” which decribes an intermediate structure
of an unreacted dry gel constitutes a structural limitation of
the claimed gel, which is a bonded gel. In this regard, see
Colin at page 298 which describes the structure of silica gel
after bonding with a monochlorosilane.
Even assuming that an unreacted dry gel structure “having
essentially one form of silanol moiety” survives the bonding step
when the silica gel is reacted and bonded with monochlorosilane,
it is not apparent that the claimed bonded silica gel product is
distinguished from prior art bonded silica gel products as
described or suggested by Colin. In this regard, in describing
prior art techniques appellants explain in their specification at
page 13, lines 1-4 that
[D]ilute hydrofluoric acid wash typically is used
to condition silica before bonding stationary phases
thereto. Such conditioning improves separation
efficiency and sample recovery because the surface
silanols are fully hydroxylated, i.e., form individual
silanol groups (emphasis added).
Moreover, Colin teaches at page 297 that maximum coverage density
of the bonded phase is obtained when a maximum number of “free
silanols” are available on the surface of the silica gel.
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