BIAXIALLY ORIENTED POLYESTER FILM FOR MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To provide the title film which is excellent in abrasion resistance and hardly meanders during traveling. CONSTITUTION:The title film contains 0.01-2.5wt.% particles which are obtd. by treating the surfaces of synthetic calcium carbonate particles having a mean particle size of 0.10-1.0mum with a high-molecular polycarboxylic acid and then with a phosphorus compd. of the formula wherein R is a 1-10C hydrocarbon group; l and m are each 1 or 2 provided l+m=3; and n is 0 or 1.