| 摘要 |
PURPOSE:To improve an erasing characteristic by specifying the ratio of the ferromagnetic powder to be added to the hexagonal ferrite magnetic powder contained in a magnetic layer at <=30pts.wt. by 70-100pts.wt. said ferrite magnetic powder. CONSTITUTION:The hexagonal ferrite magnetic powder having <=5 planar ratio and <=600 oersted coercive force is used and the ferromagnetic powder having <=4 acicular ratio, <=100emu/g satd. magnetization and <=700 oersted coercive force is used. The ratio of the hexagonal ferrite magnetic powder and the ferromagnetic powder is specified at <=30pts.wt. the latter by 70-100pts.wt. the former. The magnetic recording layer which has the decreased deterioration of the magnetic characteristics with lapse of time, the good erasing characteristic, good high-frequency characteristic, high density and high output is thus obtd.
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