Appeal No. 95-0334
Application 08/002,513
for one of ordinary skill in the art to add acetone to the
reaction medium of Fujiwara.
We agree with appellants that neither Bassford nor
Japanese '217 would have provided the requisite motivation to
add an aliphatic ketone, such as acetone, in the claimed
process of using GA as the starting material for making L-
ascorbic acid. Like appellants, we find that Bassford
provides a "teaching away" for doing so. Bassford teaches
that the solvent forms a separate layer above the reaction
medium, and it is into such solvent layer that the ketone is
dissolved upon formation in the reaction medium. Since
Bassford teaches that the dissolution of the ketone in the
solvent layer facilitates its removal from the reaction
medium, we concur with appellants that the teaching of
Bassford would not have motivated one of ordinary skill in the
art to add such a component, acetone, to the reaction medium.
Concerning Japanese '217, this reference is directed to
the use of DAGA, not appellants' GA, as the starting material
for preparing L-ascorbic acid. While Japanese '217 adds
acetone to the reaction medium for dissolving intermediate
ester compounds formed by the reaction of DAGA and acid, the
examiner has not established on this record that similar ester
-4-
Page: Previous 1 2 3 4 5 6 7 Next
Last modified: November 3, 2007