Magnetic recording medium having a magnetic layer comprising hexagonal barium ferrite magnetic particles containing tin and magnesium in specified proportions

摘要

Disclosed herein is a magnetic recording medium having a magnetic layer comprising hexagonal ferrite magnetic particles each expressed as BaO·Fe.sub.12-x-y Sn.sub.x Mg.sub.y O.sub.18 (where, 0.55≦ x≦0.88, 0.71≦y≦1.05). The hexagonal ferrite magnetic particles contained in this magnetic layer each have Sn and Mg partially substituted for Fe, the Sn and Mg being perfectly solid-soluble, thus being capable of providing hexagonal ferrite magnetic particles which are superior in crystalline properties and small in variation of composition. As a result, the coercivity distribution can be made further sensitive, both the self demagnetization and recording demagnetization in the short wave-length range can be reduced, and a higher reproducing output characteristic is attainable in the high density recording range.