| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for molding polyester sheet and film by which the sheet or the film with an excellent surface smoothness and high quality can be produced at a high speed. SOLUTION: In a method for molding the sheet by which a molten sheet of a polyester in which terephthalic acid is a main acid ingredient is extruded from an orifice-like die and is tightly stuck on a cooling roll by means of electrostatic sticking and is solidified, the method of the polyester sheet is characterized by a specific resistance of the polyester under a molten condition being 3×106-1×108Ω.cm and the cooling roll being such a cooling roll that has a microcrack surface and the molding speed of the sheet being 65-250 m/min and the method for molding the polyester film is characterized by biaxially drawing the molded sheet in both the longitudinal and the transverse directions.
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