| 摘要 |
PURPOSE:To obtain a magnetic recording medium having an excellent electromagnetic conversion characteristic and coefft. of friction by adding a specific ratio each of needle-like Cr2O3 having a specific shape and carbon black having a specific grain size to a magnetic layer. CONSTITUTION:The magnetic layer contains the needle-like Cr2O3 having <=0.1mum major axis diameter, <=0.1mum minor axis diameter and 5-20 acicular ratio at 1-20wt% by the weight of magnetic powder and contains the carbon black having >=50mmu grain size at 0.5-10wt% by the weight of the magnetic powder. The Cr2O3 having 0.1-0.95mum major axis diameter, 0.02-0.09mu minor axis diameter and 8-15 acicular ratio is more particularly preferable as the Cr2O3 to be used. The good electromagnetic conversion characteristic is obtd. even if the Cr2O3 is used up to about 20wt% by using the carbon black having >=50mmu grain size so as to co-exist at 0.5-10wt% of the magnetic powder. The good running property and running durability are thus obtd.
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