The examiner states (Answer, pages 3 and 4) that:
Borom forms a composite of fibrous silicon
carbide coated with boron nitride, in a matrix of
silicon carbide. See lines 39-55 of col. 1.
Singh discloses a process which comprises applying a
continuous coating of boron nitride (col. 3, lines
48-50) to a fibrous material which may be SiC (col.
3, line 5). The diameter of the coated fibers are
from 50 microns to 250 microns (col. 8, line 29).
Singh’s coated fibers are infiltrated with a molten
mixture of boron and silicon. One such composite
formed comprised about 65% by volume of silicon
carbide and about 10% by volume of coated fibers
(col. 18, lines 52-60).
Both Borom and Singh differ from the instantly
claimed invention only in that they use boron nitride as
the coating material instead of silicon nitride,
aluminum nitride, titanium nitride, zirconium
nitride, hafnium nitride, niobium nitride, or
tantalum nitride or mixtures thereof.
To remedy this deficiency of Borom and Singh, the examiner
relies on Rousseau to demonstrate that it would have been
obvious to one of ordinary skill in the art to substitute a
nitride of aluminum, hafnium or zirconium for boron nitride on
the fibers of the fiber reinforced silicon carbide matrix
composite described in Borom or Singh. See the Answer, page
4.
Appellants do not dispute the examiner’s findings
regarding the contents of Borom and Singh. See the amended
Brief in its entirety. Appellants, however, dispute that
3
Page: Previous 1 2 3 4 5 6 7 8 Next
Last modified: November 3, 2007