PURPOSE: To decrease permanent deformation and drop-out and to improve an S/N by incorporating at least silicone modified polyurethane and carbon black having a specific BET value in a back coating layer thereby improving the winding condition during high-speed traveling.

CONSTITUTION: The above-mentioned purpose is achieved by incorporating at least silicone modified polyurethane and carbon black having 200W500m2/g BET value in a back coating layer. A polymer prepd. by using an active hydrogen compd. having at least ≥1 siloxane bond, for example, the polysiloxanediol expressed by the general formula I as the active hydrogen compd. and bringing such compd. into reaction with isocyanate is preferred for the silicone modified polyurethane. The silicone modified polyurethane having a number average mol.wt. ranging 5,000W200,000 is preferred. The ratio of said polyurethane and other resins is preferably in a 75/25W25/75 range by weight. A preferred method for decreasing effectively the electric resistance of the back coating layer is to add carbon black having 200m2/g≤B<500m2/g BET value to the back coating layer.