Appeal No. 1997-0090
Application No. 08/083,183
silicates is avoided, since this would only increase the cost
for chemicals without any positive effect and make it
impossible to easily recover the waste liquors”. See Lundgren
at page 2, line 51 to page 3, line 4. Accordingly, inadequate
motivation exists to modify the Lundgren process for bleaching
chemical pulps by the addition of a silicate stabilizing agent
to Lundgren’s hydrogen peroxide bleaching step. That the
Whiting reference corroborates Lundgren’s teaching that
stabilizing agents are conventionally utilized in peroxide
bleaching stages for mechanical pulps adds nothing to the
relevant disclosures in Lundgren regarding this issue.
The examiner further contends in the answer at pages 3
and 6 that it is well known that the presence of a chelating
agent (as set forth in the specification at page 3, lines 29
and 30, chelating agents such as the salts of EDTA are
stabilizing agents utilized by appellants in the claimed
process) in a peroxide bleach stage acts as a stabilizing
agent for the peroxide. For factual support for this
proposition, the examiner refers to column 2, lines 49 and 50
of Peter. However, this portion of Peter does not relate to a
peroxide bleaching stage. As appellants correctly argue in
6
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