Appeal No. 2002-0865
Application No. 08/940,996
stable emulsion, and thereafter complete the polymerization
process. Fan specifically discloses the following:
Due to the fact that the emulsion is rendered shear-
stable, any convenient polymerization procedure may
then be employed without the danger of gel formation.
For example, the emulsion may be polymerized and cooled
by circulating at least part of the emulsion during
polymerization through a circulating loop outside of
the polymerization apparatus to remove the heat
generated during the polymerization reaction [column 2,
lines 44-52].
While Fan goes on to disclose that "[a]ny conventional apparatus
may be used to provide the external heat exchange loop" (column
6, lines 54-56), the examiner has not established on this record
that such conventional apparatus would include the presently
claimed low-shear pump and heat exchanger having an essentially
laminar flow profile. While such a pump and heat exchanger may
have been known in the art, and appellants do not assert
otherwise, the examiner has not established that one of ordinary
skill in the art would have considered using this type of
apparatus in the conventional closed circulating loop taught by
Fan. Accordingly, it is our judgment that the examiner has not
established that it would have been prima facie obvious for one
of ordinary skill in the art, based on Fan's disclosure relating
to a water-in-oil emulsion polymerization, to employ a low-shear
pump and heat exchanger having an essentially laminar flow
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