MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To obtain a magnetic recording medium which has the good reproduced output over the entire range from a low to high frequency and good surface characteristic with a good efficiency of production 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, 60-100emu/g saturation magnetization and >=700 oersted coercive force is selected. The ratio of the hexagonal ferrite magnetic powder and the ferromagnetic powder is made <=20pts.wt. the former with respect to 80-100pts.wt. the latter, then the magnetic recording medium having high density and high output is obtd. with a good efficiency of production. The ratio of the hexagonal ferrite magnetic powder is more preferably about 20-5wt% with respect to about 80-95wt% ferromagnetic powder. The average grain sizes of both the hexagonal ferrite magnetic powder and ferromagnetic powder are about <=0.3mum.