Appeal No. 1998-0240
Application 08/522,479
claimed helically crimped multicomponent fibers may be bonded by heating the fiber to a temperature
above the melting point of the low melting point compound yet below the melting point of the high
melting point component. (See Brief, page 7, and Pike , col. 4, lines 37-43 and col. 9, lines 17-24).2
Connor, however, describes the addition of a nucleating agent to a thermoplastic polymer, such as
polypropylene, in order to increase the bond strength of the thermally bonded fibers. (Connor, col. 2,
lines 39-51 and col. 3, lines 30-37). Furthermore, Connor specifically states that “the nucleating agent
additive can be considered to function as a bonding aid and not as an additive for enhancing fiber
strength.” (Connor, col. 3, lines 32-35). Accordingly, one skilled in the art reading the Connor
reference would expect that the addition of the nucleating agent to the Pike reference would increase
the bonding strength of the low melting point, thermally bonded fiber. Yet, one skilled in the art would
have no such expectation of improved bonding strength for the high melting point fibers as Pike teaches
that nonwoven fabric webs are produced at temperatures below the melting point of the high melting
point fiber and above the melting point of the low melting point fiber, i.e., only the low melting point
fiber melts to form bonds. Accordingly, the reference evidence relied on by the examiner fails to
establish a prima facie case of obviousness for incorporating a nucleating agent in thermoplastic
polymers having a shorter solidification period and/or higher melting point.
2Appellant’s specification incorporates the disclosure of Pike by reference in its entirety.
(Specification, page 9, lines 11-14).
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