Magnetic recording medium

摘要

In a magnetic recording medium comprising a nonmagnetic substrate and at least one magnetic layer provided on the nonmagnetic substrate, in which layer a ferromagnetic fine powder and a binder are dispersed together, the magnetic layer comprises as a substantial binder a polyurethane obtained from a polyester polyol, a chain extender and an organic diisocyanate. The ferromagnetic fine powder contains cobalt-containing iron as a main component, and the polyurethane comprises a polyester polyol containing an aliphatic dibasic acid as a dibasic acid, and a diol component, at least 70 mol% of which contains an alkyl branched side chain having at least 2 carbon atoms.