Appeal No. 1996-0191
Application 08/001,697
alleged teachings in Macholdt “that melamine resins are suitable curing agents for the epoxy resins
reported in [Kajiura] or the hydroxyl-functional resins of [Iwasawa] and
[Wooten],” in contending that one of ordinary skill in this art would have found it “obvious to employ
the tris-pyrrolidonyl triazine hardener of [Kajiura] as the curing agent for the hydroxyl-functional resins
of [Macholdt], [Iwasawa] and [Wooten] in order to attain superior heat resistance over melamine
resins” (answer, page 6). Appellants submit that there is no suggestion in the combined teachings of the
applied references to “replace the melamine crosslinkers” of Macholdt, Iwasawa and Wooten with tris-
pyrrolidonyl triazine disclosed in Kajiura (brief, pages 10-11). In view of the evidence in the Macholdt,
Iwasawa and Wooten, we find ourselves in agreement with appellants.
Appellants acknowledge that the “six primary references disclose . . . the known fact that
hydroxyfunctional acrylic and polyester powder coating resins can be crosslinked with melamine resins”
(brief, page 9). Indeed, we find that Iwasawa discloses that thermosetting powder coating8
compositions “containing an acrylic resin and a melamine derivative, namely ‘melamine-acrylic resin,’”
wherein the “melamine derivative” is “hexakisloweralkoxymethyl-melamine obtained by etherifying
hexakismethylolated melamine with lower alcohol,” were known and teaches powder coating
compositions comprising acrylic resins and “hexamethylolmelamine” derivatives which are particular
etherified products (e.g., col. 1, lines 8-14, and col. 2, lines 17-39). We find that Wooten discloses
that alkoxymelamine and hexamethoxymethyl melamines are among the melamines that are useful for
thermosetting resins containing functional hydroxyl groups such as polyester resins in thermosetting
powder coating compositions (e.g., col. 1, lines 14-16, and col. 2, lines 53-65). We find, as did
appellants (brief, page 10), that “melamine resin” is disclosed in Macholdt as a “curing component for
hydroxyl-containing polyester resins” in powder coating compositions and not, as alleged by the
examiner (answer, pages 4 and 6), for epoxy resins (col. 1, lines 55-66).
Based on this evidence, we find that the combined teachings of Iwasawa, Wooten and
Macholdt would have suggested to one of ordinary skill in this art that, in addition to melamine resins,
8The ground of rejection as stated in the final rejection (Paper No. 9) included Labana et al.,
Passmore et al. and Kanda et al. which the examiner withdrew in the answer (page 4).
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