Appeal No. 2002-1284 6
Application No. 09/098,730
of two articles to show lack of correlation between porosity and particle size. The first is a
published article entitled “High Purity/Fine Alumina” by Sumitomo Chemical Company.
The second is an article entitled “Development of Advanced Alumina
‘SUMICORUNDUM’.” Having reviewed the data present, we conclude that appellants
have not met their burden of showing unexpected results, i.e., a lack of correlation
between porosity and particle size. In re Klosak, 455 F.2d 1077, 1080, 173 USPQ 14,
16 (CCPA 1972). It is not sufficient to assert that the results obtained are unusual or
unexpected. The burden of showing unexpected results rests on those who assert them.
Appellants rely on a comparison between alumina compositions designated as AKP-
20, AKP-30 and AKP-3000 on page 2 of the Sumitamo article. It is their position that,
“the product AKP-3000 has an average sintered particle size (0.55:) that is smaller than
that of the product AKP-20 (0.57:), whereas AKP-3000 has a significantly lower fired
density, and therefore a significantly higher fired porosity than AKP-20.” See Brief, pages
6 and 7. We disagree with both appellants’ analysis and conclusion.
We find that the sintering properties of AKP-20, AKP-30 and AKP-3000 powders
are compared in a Table at page 2 of the article. The initial particle size in :m of AKP-20
is 0.4~0.6, AKP-3000 is 0.4~0.7, and for AKP-30 0.3~0.5. Each of the powders is
sintered at 1600oC. See footnote 2, right-hand column of page 2. As the particle size of
AKP-30 is smaller than that of either AKP-20, or AKP-3000 one would expect that the
sintered properties would disclose a smaller mean particle size and such is the case. As for
Page: Previous 1 2 3 4 5 6 7 8 9 Next
Last modified: November 3, 2007