MANUFACTURE OF ALIPHATIC POLYESTER FILM

摘要

PROBLEM TO BE SOLVED: To obtain a film uniform in thickness efficiently, continuously and stably by imparting proper viscosity to an extruded melt while preventing the generation of a stain. SOLUTION: In a aliphatic polyester film manufacturing method wherein a melting component based on aliphatic polyester having a main repeating unit represented by general formula -O-CH-R-CO (wherein R is H or a 1-3C alkyl group) is melted to be extruded and the obtained extruded melt is brought into close contact with a rotary cooling roll to be taken over while quenched and solidified to obtain an unstretched film, polyester to be used has a melt viscosity of 1×103-below 1×106 poise at 200 deg.C under a shearing speed condition of 10/sec and melt extrusion is performed within a temp. range from the melting temp. (Tm) of aliphatic polyester to 250 deg.C.