| 摘要 |
PROBLEM TO BE SOLVED: To obtain a recording medium of a wet-on-wet coating type with which good surface characteristics are obtd. and the reduction of surface electric resistance is made possible by using nonmagnetic powder subjected to a conducting treatment to the nonmagnetic powder in a nonmagnetic coating material forming a nonmagnetic layer of a lower layer. SOLUTION: The surface electric resistance of the nonmagnetic layer and double layer coating films is preferably <=1×10<8>Ω/sq, the specific surface area of the monmagnetic powder 20 to 80m<2> /g, the electric conductivity of the nonmagnetic powder >=200μs, the center line average roughness (Ra) of the nonmagnetic layer <=10μm and the thickness of the magnetic layer <=3μm. The nonmagnetic powder formed by subjecting metal oxide powder of zinc oxide, titanium oxide, etc., with an Sn compd., such as tin oxide, and Sb compd. alone, such as antimony solution treated tin oxide, are used as the nonmagnetic powder. The nonmagnetic layer is formed by applying the nonmagnetic coating material contg. the nonmagnetic powder and a binder on a nonmagnetic base and thereafter, the magnetic coating material contg. ferromagnetic powder and the binder is applied thereon, by which the magnetic layer is formed.
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