| 摘要 |
PURPOSE:To obtain a magnetic recording medium which is low in sliding noise and has good electrical conductivity and low light transmittance by providing a magnetic recording layer essentially consisting of ferromagnetic material powder and binder and contg. 0.1-10pts.wt. nonmagnetic metallic powder on a nonmagnetic base. CONSTITUTION:The magnetic recording layer essentially consisting of the ferromagnetic material powder and binder and contg. 0.1-10pts.wt. at least above-mentioned nonmagnetic metallic powder is provided on the nonmagnetic base. The nonmagnetic metallic powder is pulverized high-hardness nonmagnetic metallic powder for which pulverized tungsten powder is particularly preferable. The pulverized tungsten powder has a high effect of shielding light, has a high effect in decreasing the light transmittance and has a good polishing effect as said powder has extremely high hardness. The pulverized tungsten powder itself has the high electrical conductivity and contributes to a decrease of the electric resistance of the magnetic layer. There is no effect of the addition of the pulverized tungsten powder if the amt. of said powder to be added is <=0.1pt.wt. and the output decrease by the decreased density of the magnetic powder is resulted if the amt. is >=10pts.wt. and therefore, the amt. of said powder to be added is adequately 0.1-10pts.wt., more preferably 1-5pts.wt.
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