PURPOSE:To reduce the increment of the dropout and the blockade of the head by providing the coating layer containing the solid powder on both surfaces of the supporter base with the surface layer of 0.05-2mu and the back layer of 0.5mu or more and also with the former formed more minute than the latter respectively. CONSTITUTION:The coating layer containing the solid powder pigment is provided on both surfaces of the plastic base of the supporter. The surface property of the coating layer is affected largely by the grain size of the pigment. The desirable grain size is 0.05-2mu for the suface layer and 0.5mu or more (0.7-10mu preferably) for the back layer. As for the surface property, about 0.05-2mu(0.1-1.5%mu preferably) is desired for the surface layer and about 0.5mu or more (0.5-5mu preferably) for the back layer respectively. And for the thickness of the coating layer, about 0.5mu or more (1-10mu preferably) is desired at the surface layer and about 2mu or more (3-15mu preferably) at the back layer respectively. The surface electric resistance is set under 1010OMEGA/sq on the back layer.
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