PURPOSE: To obtain satisfactory running stability and to obviate spoiling of a magnetic characteristic by using carbon black having an extremely small particle size as nonmagnetic powder and making combination use of such carbon black and an org. lubricating agent.

CONSTITUTION: A back coat layer formed by dispersing and binding carbon black having ≤1mμ average particle size and org. lubricating agent to a binder is formed on the rear of a base film provided with a magnetic layer on the main plane. The carbon black of which the particle size is usually up to 0.1μm and is preferably in a 0.2W0.5mμ range is used. The reason for selecting and using particularly the carbon black as the nonmagnetic powder lies in that the small particle size like that of carbon black is hardly obtainable with other nonmagnetic powder such as graphite and that even with the other nonmagnetic particle having a small particle size the effect of decreasing the coefft. of friction after traveling for a long period is not thoroughly obtd. owing to the deterioration in the function for maintaining the adsorption of the org. lubricating agent.