Multilayer polyester foil for magnetic information carriers.

摘要

A coextruded, biaxially draw-oriented, multi-layer polyester film as a base film for magnetic tape is described, whose characteristics are that the total thickness of the multi-layer film is no more than 10 mu m, the surface roughness of the base film on the side intended for the application of an information-carrying coating has an Ra value (DIN 4768) of less than or equal to 0.010 mu m and the surface roughness of the opposite side of the base film which is not intended for application of an information-carrying coating, has an Ra value of greater than 0.010 mu m and that the film has an E-modulus in the machine direction of greater than or equal to 6500 N/mm2.