Method for producing a polyester film

A method for producing a polyester film, comprising:

• implementing a resin alloy master batch preparation step, including:
• melting and kneading a high temperature resistant resin material and a polyester resin material with a twin-screw granulator, and then forming a plurality of resin alloy master batches:
• wherein the high temperature resistant resin material is at least one material selected from the group consisting of poly-ether-imide (PEI), poly-sulfone (PSU), liquid-crystal-polymer (LCP), poly-ether-ether-keton (PEEK), and poly-amide-imide (PAI);
• wherein in the resin alloy master batch preparation step, a twin-screw temperature of the twin-screw granulator is between 280° C. and 300° C., and a twin-screw rotation speed of the twin-screw granulator is between 400 rpm and 600 rpm, so that in the plurality of resin alloy master batches, the high temperature resistant resin material is dispersed in the polyester resin material with an average particle size ranging from 50 nm to 200 nm;
• and
• implementing a film forming step, including:
• melting and extruding the plurality of resin alloy master batches with a film extruder to form a polyester film;
• wherein the polyester film includes a heat resistant layer, and the heat resistant layer is formed of the plurality of resin alloy master batches so that the heat resistant layer includes the high temperature resistant resin material and the polyester resin material.