| 摘要 |
PROBLEM TO BE SOLVED: To prevent the clogging of a head even after repeated running of a medium over the full length at high temp. and humidity and the reduction of output due to the clouding of the head at low humidity, to reduce dropout and to increase reproduction output by specifying the dry film thickness of a recording layer, the coefft. of dynamic friction to a metallic pin and the Young's modulus of the substrate. SOLUTION: This magnetic recording medium has one or more recording layers including a magnetic layer on one side of the substrate, the total dry film thickness of the recording layers is <=0.5μm and the top magnetic layer contains carbon black of >=30nm number average particle diameter. The coefft. of dynamic friction to a metallic pin at 20 deg.C and 60% relative humidity is <=0.3. A layer in contact with the bottom of the top magnetic layer contains a lubricant contg. fatty acid and fatty acid ester and nonmagnetic powder having a Mohs hardness of >=5. The total Young's modulus of the substrate in the longitudinal and transverse directions is >=1,400kg/mm<2> .
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