BIAXIAL ORIENTATION POLYESTER FILM FOR CAPACITOR AND FILM CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide a biaxial orientation polyester film in which, when the polyester film is formed by using a polymer with a titanium compound used as a catalyst, a foreign matter derived from the titanium compound such as titanium oxide particles or the like is synthesized, and a drawback such as a coarse projection or the like occurs when a molded product such as a film or the like is manufactured, and such a problem is solved, and which is preferable as a capacitor and reduces the foreign matter caused by the catalyst. SOLUTION: It is found that it is extremely effective to optimize a size and a quantity of an antimony, germanium and magnesium compound separated as a metal crystal caused by a polymeric catalyst existing in the film. That is, in the biaxial orientation polyester film for the capacitor having a thickness 0.5 to 20μm, (A) melting ratio resistance is 1×107to 5×1010Ωcm; (B) the titanium compound having no particle size substantially is contained; and (C) the number density of particles containing a titanium element in which an equivalent circle diameter is 1μm or larger is less than 5,000 pieces/mg in terms of a polymer of 1 mg. COPYRIGHT: (C)2006,JPO&NCIPI