| 摘要 |
PURPOSE:To enable much more suppression of the sagging in the middle of a magnetic tape and prevention of the decrease in output in a high range in such a stage by constituting the magnetic powder for the lower layer of >=2 kinds of magnetic powders having different coercive forces and constituting the magnetic powder for the upper layer of the magnetic powder having the coercive force higher than the coercive forces of the magnetic powder for the lower layer. CONSTITUTION:The magnetic powder of the lower layer 2B on a base 1 consisting of a nonmagnetic material such as a polyester film or the like has the two peak values mu1 and mu2 in the coercive force distribution as shown by the curve-beta for the coercive force distribution and the magnetic powder on the upper layer 2A has one peak value mu3 in the coercive force distribution as shown by the curve-alpha for the coercive force distribution. The value mu3 is made higher than the max. value mu2 of the peak value of the above-mentioned lower layer. More specifically, the respective peak values have the relation mu1<mu2<mu3. The magnetic powder for the upper layer having the above-mentioned one peak value mu3 is constituted of one kind of the magnetic powder having generally the above-mentioned peak value mu3 and on the other hand, the magnetic powder for the lower layer having the two peak values mu1, mu2 is constituted of the mixture composed of two kinds of the magnetic powders having the respective peak values mu1, mu2.
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