To obtain a material which can give a magnetic recording medium base excellent in levelness and capable of high speed revolution by using a cyclic hydrocarbon polymer having monocyclic hydrocarbon structures in the main chain or as side chains.
The monocyclic hydrocarbon structure is a usually 4-12 membered, desirably 5-8 membered, more desirably 6-membered ring. The cyclic hydrocarbon polymer having ring structures in the main chain is exemplified by a cyclic conjugated diene polymer. The cyclic hydrocarbon polymer having ring structures as side chains is exemplified by a vinyl cyclic hydrocarbon polymer. It is desirable that, in both cases, the ring carbon-carbon unsaturations have been hydrogenated. It is desirable that the cyclic hydrocarbon polymer has a weight-average molecular weight (Mw) of 10,000-1,000,000 in terms of the polystyrene as measured by GPC and a molecular weight distribution (Mw/Mn) of 6.0 or below.
NAGAMUNE TSUTOMU
OBARA TEIJI
TAKAHASHI HARUHIKO
Next Patent: ELECTRICAL INSULATION COMPOSITION AND POWER CABLE