| 摘要 |
PURPOSE:To obtain a magnetic recording medium having good vertical orientability with good productivity by making combination use of hexagonal ferrite magnetic powder and acicular ferromagnetic powder. CONSTITUTION:The hexagonal ferrite magnetic powder having >=5 plate ratio and <=600 oersted coercive force is selected. The ferromagnetic powder having >=4 acicular ratio, 600-100emu/g saturation magnetization and <=700 oersted coercive force is selected. The ratio of the hexagonal ferrite magnetic powder and the ferromagnetic powder is made <=80pts.wt. the latter with respect to 20-100pts.wt. the former, then the magnetic recordingmedium having a good erasing characteristic, good high-frequency characteristic, high density and high output is obtd. The ratio of the ferromagnetic powder is more preferably about 80-5wt% with respect to about 20-95wt% the hexagonal ferrite magnetic powder. The average grain sizes of both the hexagonal ferrite magnetic powder and ferromagnetic powder are about <=0.3mum.
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