Appeal Number: 2005-2227 Page 5
Application Number: 09/845,356
emitting material, 4,4’ –N, N’ –dicarbazole-phenyl (CBP) was known to be a blue-emitting
material, and DCM2 was known to be a red-emitting material. The references describe other
light-emitting materials as well. The use of known materials in a known combination to achieve
a known result establishes prima facie obviousness.
We also note that claim 25 does not require that the red, green, and blue light-emitting
materials each contribute to the white light emission, the claim merely requires the presence of
materials that can be properly described as red, green, and blue light-emitting materials. Baldo
and Forrest describe organic light-emitting devices (OLEDs) containing Ir(ppy)3, a green light-
emitting material, with CBP, a blue light-emitting material, as a host material. Forrest further
describes mixing light-emitting materials together including Ir(ppy)3 as sensitizer, CBP as host,
and DCM2, a red light-emitting material, as fluorescent dye (Forrest, col. 14, ll. 63-68). These
materials are red, green, and blue light-emitting materials as required by the claim. Whether they
produce those colors within the device is a question we need not answer, the claim does not
require color production from those specific materials. Egusa indicates that it was known to
produce white light with a number of light-emitting materials and it would have been obvious to
select those materials for use in the devices of Baldo and Forrest and apply the correct biasing
voltage when a white light-emission was desired. Claim 25 does not exclude the addition of
other light-emitting materials.
Appellant’s second argument, that the combination of the teachings of the references
would not result in the inventive device, is based on the use in Baldo of CBP as a host rather than
a blue light-emitting material and on the use in Forrest of Ir(ppy)3 as a sensitizer. According to
Appellant, the Examiner’s proposed modification renders Baldo and Forrest unsatisfactory for
their intended purposes (Brief, p. 15). We agree with the Examiner’s well-stated response in the
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