Appeal No. 1998-1353 Page 7
Application No. 08/488,288
Barker describes floccular compositions containing ultrafine inorganic particles, a size-stabilizer,
and a flocculation modifier which comprises a polyelectrolyte (col. 1, line 58 to col. 2, line 9). We
agree with Appellants that Barker does not disclose an agglomerate having at least 70 weight percent
oxide particles as required by claim 1 (Brief, page 5). Note the paragraph bridging columns 3 and 4
which states that “concentrations of ultrafine particles in the floccular composition can be as high as
60% by weight ...” In this discussion, “ultafine particles” refers to ultrafine inorganic particles with
which particles of size-stabilisers are combined. Baker suggests that concentrations of ultafine inorganic
particles above 60% by weight are not possible and therefore, concentrations in the claimed range are
not obvious from the teachings of Barker.
With respect to the process of claim 6, we note that Barker forms the composition by
flocculation and, as explained above, claim 6 excludes flocculation.
We conclude that the Examiner has failed to establish a prima facie case of obviousness over
Barker.
The Rejection over Perry or Browning
Perry and Browning each generally describe the process of agglomeration. As pointed out by
the Appellants (Brief, page 6), neither of these references describe agglomerating monodisperse
spherical oxide particles. The Examiner notes that the monodisperse oxide particles were known in the
prior art (Answer, page 8) and concludes that it would have been obvious to treat the monodisperse
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