PRODUCTION OF POLYESTER FILM

摘要

PURPOSE:To produce a polyester film while efficiently adjusting the polymer intrinsic viscosity of the film. CONSTITUTION:In a method for producing a polyester by supplying polyester chips dried by a dryer to an extruder to melt and extrude the same and casting the extrudate on the surface of a casting drum, a small amt. of moisture is supplied to the chips in the extrusion process before the chips are melted and partial hydrolysis due to moisture is generated in molten polyester to adjust the polymer intrinsic viscosity of the film.