Appeal No. 2006-2247
Reexamination Nos. 90/006,554 and 90/006,894
1 example, problematic amounts of carboxylic acids to separate at the
2 end of process from the desired PVNO end-product.” (Appeal Brief
3 at 5-6.)
4 15. According to the appellant, the inventors solved the carboxylic acid
5 problem of the prior art with the invention, which reduced the amount
6 of acid by increasing the amount of water to at least 25% by weight,
7 while at the same time using the specified catalysts to maintain
8 “industrially-suitable rates of reaction.” (Appeal Brief at 6.)
9 16. Claims 1 and 5 of the ‘684 patent are representative of the appealed
10 subject matter and are reproduced as follows:
11 1. A process for preparing polyvinylpyridine N-oxides,
12 comprising:
13 oxidizing polyvinylpyridines in an aqueous hydrogen
14 peroxide solution having a water content of at least 25% in the
15 presence of an acid and a catalyst of an oxide, acid or salt
16 thereof of an element of Group 5b, 6b, 7b or 8.
17
18 5. The process of claim 1, wherein the oxidation is
19 conducted in the presence of from 0.1 to 1% by weight of
20 sodium tungstate, phosphotungstic acid, tungstic acid, sodium
21 molybdate, phosphomolybdic acid, molybdic acid or mixtures
22 thereof.
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