Appeal No. 2004-2294
Application 10/002,343
teachings of Miyoshi and Mitsui and of Miyoshi and Nishino to one of ordinary skill in this art
at the time the claimed invention was made.
Accordingly, since a prima facie case of obviousness has been established by the
examiner, we have again evaluated all of the evidence of obviousness and nonobviousness based
on the record as a whole, giving due consideration to the weight of appellants’ arguments in the
brief. See generally, In re Johnson, 747 F.2d 1456, 1460, 223 USPQ 1260, 1263 (Fed. Cir.
1984); In re Piasecki, 745 F.2d 1468, 1472, 223 USPQ 785, 788 (Fed. Cir. 1984).
The principal issues in this appeal are whether it would have been obvious to one of
ordinary skill in this art to modify the catalyst of Miyoshi by replacing the cordierite substrate
thereof with the zirconium titanate ceramic substrate of Mitsui and/or the calcium aluminate
ceramic substrate of Nishino, and if so whether either or both of the said ceramic substrates have
the properties of resistance to alkali metal migration below 1000°C, and a coefficient of thermal
expansion of less than about 25x10-7/°C (25-800°C), which characterize the ceramic substrates
of the claimed catalysts encompassed by appealed claims 1 and 3. Indeed, there is no dispute
that the catalysts disclosed by Miyoshi satisfy all of the limitations of appealed claims 1 and 3
except for the ceramic substrate.
Appellants acknowledge that “Mitsui teaches that in . . . harsh [exhaust gas]
environments carrier supports made of cordierite and coated with alumina suffer from corrosion
by sulfur oxides, and carriers made of titanium oxide are not heat resistant,” and thus teaches the
use of a zirconium titanate ceramic support “which offers resists [sic] to sulfur oxide and has
heat resistance” (brief, page 5). Appellants further acknowledge that “Nishino teaches that
carriers made with calcium aluminate, titanium oxide . . . or alumina-coated cordierite do not
have heat resistance and long life,” and teaches “an improved catalyst carrier composed of a
solid mass or core of calcium aluminate” with a layer of titanium oxide formed on the surface of
the calcium aluminate (id., page 7).
Appellants argue with respect to the combined teachings of Miyoshi and Mitsui (id., page
5), and apparently would have similarly argued with respect to the combined teachings of
Miyoshi and Nishino (cf. id., page 7), that Miyoshi is not concerned with improving the NOx
trap support substrate, or for otherwise modifying the support, and thus one of ordinary skill in
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