METHOD FOR MANUFACTURING POLYESTER FILM

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a polyester film while preventing the adhesion of foreign matter to a die lip or the accumulation and growth thereof on the die lip even in long-time operation without lowering the quality and film forming properties of the polyester. SOLUTION: In manufacturing the polyester film by extruding a polyester resin from a die in a molten state to cool and solidify the same on a cooling medium in a close contact state, moist air is supplied to the periphery of the die lip to control humidification.