| 摘要 |
PURPOSE:To obtain a magnetic recording medium which has large reproduced output and permits high-density recording by using fine magnetic material particles of which the average particle size is of a limited length and the volumetric packing rate of the fine magnetic material particles in the magnetic layer is specific % or above. CONSTITUTION:The particle size of fine magnetic material particles consisting of hexagonal ferrite is made 0.02-0.15mum and the volumetric packing rate of the fine magnetic material particles in a magnetic layer contg. said particles is made >=42% in a magnetic recording medium provided with said magnetic layer on a substrate. The fine magnetic material particles consisting of hexagonal ferrite are exemplified by, for example, M type (magneto-plumbite type), W type hexagonal barium ferrite, strontium ferrite, lead ferrite, orcium ferrite or the solid soln. thereof or ion substituted matter thereof. The fine magnetic material particles consisting of hexagonal ferrite having 200-2,000Oe coercive force are mainly used.
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