Appeal No. 1999-0097
Application No. 08/532,976
Appellants do not dispute that Kolycheck, the primary
reference, discloses, like appellants, a magnetic recording
medium comprising a magnetic layer on a non-magnetic support
wherein the magnetic layer contains ferromagnetic powder
dispersed in a polyurethane resin binder. Also, appellants do
not dispute the examiner's finding that the polyurethane resin
binder of Kolycheck is prepared by reacting long chain and
short chain diols within the claimed molecular weight ranges
and an organic diisocyanate. Kolycheck does not teach that
the long chain diol is the sulfonated one of the claimed
formula, and the reference also does not teach that the long
chain diol is present in the claimed amount of 1 to 5 mol%.
To make up for these deficiencies in Kolycheck, the examiner
cites Ohkubo for its teaching of a magnetic recording medium
comprising a magnetic layer containing a ferromagnetic powder
dispersed in a polyurethane binder wherein the polyurethane
binder is prepared with appellants' long chain sulfonated
diol. In addition, Ohkubo exemplifies amounts for the long
chain diol that fall within the claimed range. Again,
appellants do not dispute that Ohkubo employs a sulfonated
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