Tdk Corporation

Shuji Sakaguchi

Kazushi Tanaka

Akinori Nishizawa

In a magnetic recording medium which comprises a magnetic layer having magnetic metal powder and a binder as major components, the magnetic layer being disposed on one side of a non-magnetic support member, the binder comprises a vinyl chloride copolymer, a polyurethane resin having a group which contains metal sulfamate as a functional group, and a curing agent. The polyurethane resin comprises a group containing metal sulfamate by 0.5 to 3 per molecule, a blending weight ratio of the vinyl chloride copolymer and the polyurethane resin of 30/70 to 70/30, and the curing agent is present in an amount of 10 to 60 weight parts to 100 weight parts of the total of the vinyl chloride copolymer and the polyurethane resin. The invention also provides a magnetic recording medium which further comprises a non-magnetic underlayer and a backcoat layer, wherein a binder comprising polyurethane resin having a group which contains metal sulfamate also is used. The binder improves the dispersion property, coating material stability and coating material viscosity of the magnetic layer, non-magnetic underlayer and backcoat layer to improve the electro-magnetic characteristics of the magnetic recording medium.

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Nagano, Japan

Shuji Sakaguchi