Appeal No. 2001-2554 4
Application No. 08/925,321
claimed subject matter and establish a prima facie case of obviousness. None of the
references before us except for the “admitted prior art” is directed to the presence of
hexenuronic acid in chemical cellulose pulp let alone the presence of hexenuronic acid
wherein at least 50% of the hexenuronic acid is removed by the process. The examiner
relies upon the teaching at page 4, lines 13-22 of the instant specification as being
admitted prior art which discloses the presence of hexenuronic acid. That section of the
specification reads as follows:
It is known that cellulose pulps contain 4-O-methyl-"-D-
glucuronic acid groups (glucuronic acid groups). According
to the invention it has been discovered that sulphate pulps
also contain in addition to glucuronic acid groups, a significant
amount of 4-deoxy-$-L-threo-hex-4-enopyranosyl uronic acid
groups (i.e. hexenuronic acid groups) bound to xylan. The
amount of hexenuronic acid in some pulps is even substantially
greater than the amount of known glucuronic acid groups. The
term “hexenuronic acid” as used in the present specification
encompasses all 4-deoxy-$-L-threo-hex-4-enopyranosyl uronic acid
groups.
Based upon the second sentence of the aforesaid paragraph which opens with the
phrase, “[a]ccording to the invention,” we cannot agree with the examiner’s determination
that this paragraph constitutes prior art. Nonetheless, a prima facie case of obviousness
could have been established were the references of record to have inherently disclosed the
claimed method such that the presence of hexenuronic acid was reduced by at least 50%.
In this respect EP’695 is directed to a process for bleaching lignocellulose pulp. See
page 2, lines 43-47. We find that the lignocellulose pulp relates to chemical pulp
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