| 摘要 |
PURPOSE:To obtain a magnetic recording medium suitable for a video tape, etc. to be run at a high speed by providing a back layer dispersed with nonmagnetic powder in a binder essentially consisting of a prescribed resin to the surface of a base on the side opposite from the magnetic layer thereon. CONSTITUTION:The magnetic layer is provided on one surface of the nonmagnetic base and the back layer formed by dispersing the nonmagnetic powder into the binder essentially consisting of a polyurethane resin and vinylidene chloride resin is provided on the surface on the opposite side. The polyurethane resin is the polyurethane resin including the repeating unit having one kind of the polar group selected from the group consisting of -SO3M, -COOM, -SO3M, and -PO(OM'), where M is an H atom, alkali metal atom, M' is an H atom, alkali metal atom, and lower hydrocarbon group. The content of the repeating unit in the polyurethane resin is 0.001-5mol%. The weight ratio of the polyurethane resin and the vinylidene chloride resin is in a 30:70-60:40 range. A polyisocyanate resin may be added to these resins.
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