PURPOSE: To obtain a polyester composition giving a film having excellent flatness, abrasion resistance and scratch resistance and suitable for magnetic tape, photographic film, graphic arts film, etc., by adding acicular inorganic particles to a polyester.
CONSTITUTION: The objective composition is produced by compounding (A) a polyester composed of an aromatic dicarboxylic acid as a bifunctional acid component and a glycol component (preferably a polymer containing alkylene terephthalate or alkylene naphthalate as main constituent unit) with (B) preferably 0.01-5wt.% of acicular particles of an inorganic substance (preferably titanium oxide, aluminum oxide or zirconium oxide). The component B is preferably dispersed in glycol, etc., to be used as a raw material for the component A, slurrying the mixture and directly adding the slurry to the polymerization reactional system or kneading the slurry into the polyester. The component B, e.g. aluminum oxide, is produced by subjecting aluminum successively to alkylation, hydrolysis and thermal decomposition.
AOYAMA MASATOSHI
YOSHIDA MINORU
