| 摘要 |
PURPOSE:To obtain a magnetic recording medium having good sensitivity and good durability and running characteristic of a recording layer by incorporating an arom, azo org. pigment having a prescribed length of max. absorption wavelength into the magnetic layer. CONSTITUTION:This magnetic recording medium is incorporated with the arom. azo org. pigment having 450-600mum max. absorption wavelength into the magnetic layer. Since the azo compd. is incorporated into the magnetic layer in the above-mentioned manner, the dispersion of magnetic material particle is good and the S/N and output are remarkably improved. The azo compd. is expressed by formula I and the compd. expressed by formula I includes formula II, formula III and formula IV. In the formulas lambdamax is the max. absorption wavelength. The azo compd. is preferably added at 0.01-20pts.wt. to 100pts.wt. magnetic particles and is more preferably added at 0.5-7pts.wt. thereto. The effect of addition is poor if the amt. of the addition is too small and a problem arises on the contrary in magnetic characteristics, mechanical strength, etc. if said compd. is added too much.
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