Thin oriented filled polyester films with slight roughness, manufacturing process and use of these films in the preparation of magnetic tapes.

摘要

Thin, filled, drawn polyester films, single-layer or composite and comprising at least one filled outer layer which has a total roughness lower than 0.15 microns, this filled layer containing from 0.02 to 0.3% of a fine filler (titanium oxide etc) with a median diameter of lower than 0.5 microns and a volume shape factor greater than 0.08 and less than 0.02% of a coarse filler (calcium carbonate, etc) which has a median diameter equal to or greater than 0.5 microns. These films can be employed for the manufacture of magnetic tapes, especially video tapes.