Appeal 2007-2893
Application 10/818,885
Second, Proctor teaches that the heat-transfer liquid “substantially fills the
sealed cavity” (col. 2, ll. 33-34) but does not expressly teach that the cavity
is filled to at least 95 percent of its volume.
Park teaches a cooking utensil having a double-layered structure
which preserves heat efficiently as well as providing even heat distribution
to materials within the utensil (Park, abstract). Park’s cooking utensil is “at
least partially filled with a heat conduction medium . . ., such as silicon oil or
other suitable materials known to one of ordinary skill in the art” (Park, col.
4, ll. 40-43). More specifically, Park teaches that the sealed cavity formed
between the inner and outer walls of the utensil be “filled with silicon oil up
to about 55 to 90% by volume” (Park, col. 4, ll. 43-44).
Accordingly, Park compliments the teachings of Proctor by teaching
that silicon oil is recognized by those of ordinary skill in the art to be a heat-
transfer oil that is suitable for filling a cavity formed between two sealed
walls of a cooking container. Further, as discussed above, both Park and
Proctor identify that a variety of heat-transfer materials are known in the art
and are suitable equivalents for filling the cavity formed between two sealed
walls of a cooking container. Therefore, we find that it would have been
prima facie obvious to modify Proctor with the teachings of Park to include
silicon oil as the heat-transfer oil. Where, as here, the prior art recognizes
two components to be equivalent, an express suggestion to substitute one for
another need not be present in order to render such substitution obvious. In
re Fout, 675 F.2d 297, 301, 213 USPQ 532, 536 (CCPA 1982).
In addition, both Proctor and Park teach that the cavity formed
between the inner and outer wall of the container is “at least partially,” e.g.,
8
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: September 9, 2013