POLYESTER FILM FOR MAGNETIC RECORDING MEDIA

摘要

The method prevents film slipping characteristics and drop out caused by the need of the film thinning. This status can be improved by inserting non-activated particle into the base film. However, because of the particle size problem and a phenomenon of condensation, the dropout could be much improved. This invention is devised to solve the above problem by offering the names of particles and their mixture formula: a polyester (A) consisting of 0.01-0.1 % of Li, CA, P element; a polyester (B) conisting of oxide of silicon; a mixture formula of the above particle (A) and (B): 10<=P/(Ca+Li)/S<=100; a particle distribution formula d25/d75 < 1.4 where d = diameter (%).