Appeal No. 1997-2745 Page 6
Application No. 08/212,175
in, an otherwise old composition … such terms do not differentiate the claimed
composition from those known to the prior art”).
Stevens discloses a paint stripper and varnish remover composition comprising
(a) about 10% to about 60% by weight of a terpene compound, e.g., d-limonene; (b)
about 10% to about 50% by weight of N-methylpyrrolidone, a highly polar, water-
miscible solvent; and (c) about 2% to about 20% by weight of one or more terpene
emulsifying surfactants. It appears to this merits panel that the Stevens composition
bears a close relationship to the composition recited in claim 21. Consider, for example,
that component (a) in claim 21 may be a terpene compound such as limonene.
Consider also that, most preferably, the polar organic solvent recited in claim 21 (b) is
miscible with water (Specification, page 7, lines 8 through 20). Compare the Stevens
disclosure that N-methylpyrrolidone is a highly polar, water-miscible solvent (column 6,
lines 10 and 11).
All in all, it would appear obvious, and well within the skill of the art, to select a
relatively high amount of terpene compound and N-methylpyrrolidone within the
framework of Stevens’ disclosure, and thus to arrive at the subject matter sought to be
patented in claim 21. Further, the paint stripper compositions of Stevens may include
about 10% to about 60%, preferably about 20% to about 40% of a high flashpoint, high
kauri-butanol solvent selected from the group consisting of polycarbonates (including
ethylene carbonate, propylene carbonate, and butylene carbonate) and glycols and
glycol ethers (column 8, lines 33 through 39). Glycols include, inter alia, ethylene glycol
and propylene glycol (column 8, lines 52 and 53). In this regard, claim 21 (b) recites “at
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