Appeal 2007-3918
Application 10/203,926
STATEMENT OF THE CASE
The subject matter on appeal is directed to foam rubbers having
expanded microspheres and methods of making the same (Specification 1-
2). According to page 7 of the Specification, the microspheres used
“preferably have an unexpanded diameter of 5 to 10 um and an expanded
diameter of between 300 µm to 1000 µm. . . . [at] an expansion temperature
of between 120oC and 180oC . . .” Tables 1 through 6 show employing 3
parts by weight of commercially available Expancel 092 DU120
microspheres in various rubbers to obtain a void fraction of 35 to 60%
(Specification 5 and 8-10). The resulting foam rubbers are said to be
“devised primarily for use as acoustic decoupling or insertion loss material
for marine applications” (Specification 2 and Br. 7). Further details of the
appealed subject matter are recited in representative claims 1and 13
reproduced below:
1. A foamed rubber, wherein the foamed rubber has a plurality of
microvoids comprising microspheres incorporated therein, and wherein the
microspheres are expanded during heating and vulcanisation of the rubber
such that the volume fraction of the expanded microspheres is 35-80% in the
foamed rubber, and the microspheres have an expanded diameter of between
400 µm and 1000 µm.
13. A method of manufacturing a foamed rubber, said method
comprising the steps of:
(i) providing a rubber;
(ii) incorporating additives;
(iii) adding and mixing expandable microspheres into the rubber
composition; and
2
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 Next
Last modified: September 9, 2013