Appeal No. 1999-1180
Application No. 08/751,557
3, line 6.) According to Morikawa, palladium is an excellent
hydrogenation catalyst, but it is susceptible to chemical change
(e.g., it is soluble in hydrochloric acid in the presence of
oxygen) and can sinter easily because it has a lower melting
point relative to other platinum group metals. (Page 4, lines
4-15.) Consequently, the life of a palladium catalyst is said
to be "not necessarily long." (Id.) Morikawa further teaches:
"Elements or chemical compounds in which the surface hydrogen
atom concentration is high are considered to be suitable
addition constituents from the viewpoint of obtaining hydrogen
reduction characteristics." (Sentence bridging pages 4-5.) In
addition, Morikawa discloses:
[F]rom the viewpoint of hydrochloric acid resistance,
it is desirable to add titanium, zirconium, hafnium,
niobium, or tantalum, which are selected from the
elements which have high affinity with hydrogen.
Amount of this addition is 50-0.01% by weight relative
to the main constituent, or, preferably 30-0.1% by
weight.
(Page 5, lines 16-20; Preparation Examples 1-8; Application
Example 1; and Comparison Example 1.)
Based on these prior art teachings, we determine that the
examiner has presented substantial evidence to support a prima
facie case of obviousness within the meaning of 35 U.S.C. § 103.
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