Appeal No. 2006-2649 Page 4
Application No. 10/336,259
prevent formation of “a silicon carbide/oxide film at the surface of [an electrical] contact
when exposed to electrical energy.” Examiner’s Answer, pages 4-5.
We agree with the examiner that the cited references would have made the
composition of claim 1 prima facie obvious. As the examiner noted, La Scola teaches
all of the components of the claimed composition except for the hydroxy-functional
organic compound: an organopolysiloxane with at least two hydroxy groups per
molecule (see column 2, lines 14-25 and 51-53); a crosslinking agent of the recited
formula (see column 3, lines 28-52); an electrically conductive filler comprising silver-
coated mica particles (see column 1, lines 67-68); and a metal salt of a carboxylic acid
as a condensation catalyst (see column 5, lines 29-32).
Asai teaches that “silicone products are used in electrical equipment. . . . For
example, . . . silicone rubber compositions are used as adhesives, sealants, casting
agents, coating agents, etc.” Page 2. “[W]hen such silicone products are used in the
vicinity of electrical contacts . . . a decline in the conductivity of the electrical contacts
may occur, and, in extreme cases, conduction may disappear altogether and electrical
contact functionality may be lost.” Page 3. Asai explains why:
[S]ilicone products typically contain . . . volatile organosiloxane oligomers
as by-products and residues of the starting materials. . . . [I]t is believed
that faulty conduction at electrical contacts is due to the fact that
organosilane or organosiloxane oligomers . . . volatilize at normal
temperature or under heating and, upon reaching an electrical contact,
undergo a chemical change under the influence of the discharge energy
. . . and form insulating substances, such as silicon dioxide, silicon
carbide, etc.
Id.
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