Appeal No. 1997-4318
Application 08/469,806
explain why one of ordinary skill in this art would have recognized that the range disclosed for the
organic binders would apply to undisclosed inorganic binders.
The other applied references would have reasonably taught one of ordinary skill in this art to use
different amounts of sodium silicate as binders for, inter alia, cements, coating compositions, fertilizers,
detergents and clays. The sole reference which discloses the use of sodium silicate with an inorganic
pigment is 3M GB ‘259, wherein the reflective pigment particles, used in “liquid paint-like coating
compositions,” 6 are “clusters or agglomerates in the range of at least 2 microns in diameter up to 70
microns in diameter and consisting of an average size below 2 microns bound together by an inert
transparent binder” and the “ordinary paint pigment of commerce” can be titanium dioxide that is
“blended with sodium silicate solutions and atomized” in order to bond the particles together “in discrete
crush-resistant” manner (e.g., page 1, line 44, to page 2, line 15). The pigment particles can be made
weather resistant by treatment with an acid solution, and the resistance can be further increased by
“firing at raised temperatures” (page 2, lines 15-21). In the reference Example, “twenty parts by weight
of standard titanium dioxide pigment . . . [is] mixed with 25 parts by weight of sodium silicate,” wherein
the “tiny spherical clusters of the original smaller titanium dioxide particles [are] bonded together with
sodium silicate,” the particles being further treated with aqueous ammonium chloride, dried and fired at
elevated temperatures “to obtain a mass of clusters in the size range of 2 microns up to about 40
microns” (page 2, lines 33-84). It is further disclosed in 3M GB ‘259 that other pigments may be used,
including red iron oxide (page 2, lines 76-84). We find that the pigment particle size range disclosed in
this reference overlaps with the claimed particle size range in claims 13 and 26, and that the amount of
binder suggested by the reference in the Example to be necessary in order that the particles are resistant
to crumbling, that is, crush-resistant when used in the paint-like compositions, is well above the claimed
weight percent range in these claims.
In Ferrigno, alkali metal silicates bind anhydrous mineral pigment particles together for calcining
(e.g., col. 4, lines 14-30). Thus, this reference teaches that the binder is used in amounts of 1 to 10
6 We find that 3M GB ‘259 (page 1, lines 20-29) cross references 3M GB ‘258 with respect to the
use of “novel reflective pigment particles” in “liquid paint-like coating compositions,” the latter reference
(page 3, lines 37-79) in turn cross referencing the former.
- 9 -
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 Next
Last modified: November 3, 2007