Magnetic recording medium having a glass substrate, heat retaining non magnetic metal layer formed over the substrate, amorphous nip layer, Cr layer and magnetic layer

摘要

A magnetic recording medium comprising a substrate, a ground layer formed over at least one surface of the substrate, and a magnetic layer formed over the ground layer, the ground layer being formed of a material containing at least 95% by weight of Cr. The substrate comprises a base of glass plate, a nonmagnetic metal layer formed over at least one surface of the base, and an amorphous NiP layer formed over the nonmagnetic metal layer. The nonmagnetic metal layer is formed of a material containing at least 95% by weight of Cr, or a material containing at least 95% by weight of Ti or a material containing at least 95% by weight of Cr-Ti alloy. The recording medium has excellent flatness and a high coercive force.