| 摘要 |
PURPOSE:To obtain a magnetic recording medium which has substantially high electrical conductivity and hiding characteristic, good dispersibility in a magnetic coating compd. and excellent stagnation stability by incorporating a carbon black contg. a specific ratio of sulfur into a magnetic layer. CONSTITUTION:This recording medium contains the carbon black having <0.02wt% sulfur content in the magnetic layer. The sulfur content is further preferably <=0.01wt%, more particularly <=0.005wt%. The amt. of the carbon black to be added is 0.5-20pts., more particularly preferably 3-15pts. per 100pts.wt. magnetic material. The particle size of the carbon black is not the main factor to determine the performance and the carbon black having 20-500g/cm<2> specific surface area is preferably used. The carbon black may be incorporated into the back coat layer on the side opposite from the magnetic layer on the substrate, in addition to the magnetic layer and may be further incorporated into a film in order to decrease the light transmittivity of the film and the strength thereof if the substrate is the film.
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