| 摘要 |
PURPOSE:To improve the coefft. of friction on the surface of a magnetic layer, squareness ratio and the SN ratio of short wavelength signals by incorporating a methyl ethyl ketone, cyclohexanone and arom. nonpolar solvent at respectively specified ratios into the org. solvent of a magnetic coating compd. CONSTITUTION:The magnetic coating compd. prepd. by dispersing a magnetic layer forming material contg. a resin component and ferromagnetic powder into the org. solvent is formed. A resin having high hardness such as vinyl chloride copolymer and resin having softness such as polyurethane resin are preferably used in combination as the resin component. Pulverized ferromagnetic metallic powder having >=42m<2>/g specific surface area (SOBET) is particularly advantageous as the ferromagnetic powder. The methyl ethyl ketone is incorporated within the range of 40-80wt%, the cylohexanone within the range of 5-59.5wt% and the arom. nonpolar solvent within the range of 0.5-20wt% into the org. solvent.
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