| 摘要 |
PURPOSE:To obtain the titled medium having excellent heat resistance, with less surface discontinuity, and having an excellent recording and reproducing characteristic by laminating a nickel film, a magnetic film, and a protective film on a molded body consisting of a resinous composition composed of polybutadiene rubber and other specified components and having >=110 deg.C Vicat softening temp. CONSTITUTION:The resinous composition is composed of 5-30wt% polybutadiene rubber contg. >=50wt% butadiene component, 0-20wt% methyl methacrylate, 15-65wt% alpha-methylstyrene, 5-50wt% styrene, and 15-30wt% vinyl cyanide. Among the compositions, the one having >=110 deg.C Vicat softening point is used. The obtain the contents of the respective components and the Vicat softening point, the mixing ratio of each component in the respective latices A and B is regulated or the mixing ratio of the latices A and B is regulated or both regulations aare combined. The obtained composition is pelletized and formed in the shapes of a disk, a cylinder, etc., by injection molding, etc., to obtain the molded body.
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