Appeal No. 2000-1860 5
Application No. 08/679,243
specification, page 6. We find that the reference discloses silica sol modified with a
metalate and forming an insoluble silicate at a pH between 5 and 12 as required by the
claimed subject matter. See column 1, lines 15-20 and column 2, lines 66-69 which
additionally discloses amphoteric metals. We find that the structure is disclosed at
column 3, lines 20-32. We find that the specific ratio of gram atoms of metal to silicon
required by the claimed subject matter is disclosed at column 3, lines 44-45. We further
find that the initial colloidal silica sol utilized is sold commercially as “Ludox.” This
colloidal sol is described as the starting material to which aluminum ions are subsequently
introduced. See Examples 1 and 3. In addition, there is no disclosure of “Ludox AM“
utilized in the Kinderman reference. Accordingly, on the record before us, there is
nothing to show that Ludox AM of the Kinderman reference possesses either the
requisite amphoteric material or any or all of the characteristics of the product produced
under U. S. Patent No. 2,892,797, issued more than 40 years ago.
As a further deficiency, although the pH range disclosed by Kinderman overlaps
that of the claimed subject matter, the phosphate ion present is disclosed as being present
in an amount of about 0.1 percent by weight. See column 2, lines 40-45 and claim 3.
Significantly, we find that Example 1 discloses the presence of a phosphate ion in the
form of phosphoric acid present in the amount of 0.1 parts by weight in conjunction with
1.0 normal lithium hydroxide, LiOH. A casual calculation of the phosphoric acid
content indicates that it is present in an amount of 0.11 parts per hundred or
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