Appeal No. 2005-0440
Application No. 09/994,075
the same problem as the appellants’ claimed invention.
(Specification at 1-2.) To solve the problem of alkaline
darkening associated with the presence of calcium carbonate
filler in the pulp, WO ’308 teaches the use of an aqueous
solution of “any type of bleaching agent” such as sodium
hydrosulfite, e.g. by application of an aqueous solution of the
sodium hydrosulfite on the paper produced from the pulp. (Page
3, lines 3-6; page 4, line 29 to page 5, line 9; Examples 1 and
3; Tables 1 and 3.)
Eckert discloses (column 1, lines 58-65):
More usually, unbleached lignocellulosic pulps
are bleached or brightened to a brightness consistent
with the planned utilization of the pulp, brightness
being a measure of pulp reflectivity under
standardized conditions. Pulp bleaching is most often
a multi-stage process employing various chemicals to
remove or alter the lignin of the lignocellulosic pulp
such that the resultant pulp is no longer light
absorbing or dark in color. [Emphasis added.]
Eckert further teaches that reducing agents (e.g., sulfurous
acids, hydrosulphites, borohydrides, amineboranes, and
bisulfites) or oxidizing agents (e.g., chlorine based compounds,
peroxides, ozone, oxygen, peracids, permanganates, and
chromates) are commonly used as bleaching agents. (Column 1,
claims stand or fall together and confine our discussion to
representative claim 1.
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