Appeal No. 1997-0666
Application 08/338,830
The appealed claims stand rejected under 35 U.S.C. § 103 as unpatentable over
Barraclough combined with Leister.
We reverse.
The subject matter on appeal is directed to pigment compositions comprising (a) a
mixture of copper phthalocyanines (CuPCs) containing, on average, from 0.1 to 3 methyl
groups per Pc nucleus and (b) a basic CuPc deflocculating agent. Appellants have found that
the presence of methyl groups in a mixture of CuPCs, particularly where unsubstituted CuPc in
alpha form is present, functions to inhibit the tendency of alpha-form CuPc to recrystallize in the
presence of solvents, thus inhibiting a decrease in color strength and a bathochromic hue shift,
on storage. See appellants' specification at page 2, first full paragraph and the brief at page 3.
With respect to appellants' claimed component (a), appellants explain that such a mixture of
methyl-CuPc may be composed of CuPCs having different numbers of methyl groups. For
example, each methyl-CuPc in the composition may contain 1, 2, 3 or 4 methyl groups on the
phthalocyanine (Pc) nucleus and a typical composition may contain any or all of these together
with CuPc which is free from methyl groups. See the specification at page 2, third full
paragraph. Appellants also point out that another essential feature, as defined in the claim, is
the combination with the copper phthalocyanine mixture of a deflocculating agent which
appellants describe as a basic CuPc containing up to four basic groups selected from the
Formula (1) and Formula (2) as set forth in independent claim 12. Appellants' pigment
compositions find use in paints and plastics.
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