METHOD FOR PRODUCING CELLULOSE TRIACETATE FILM AND METHOD FOR HANDLING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a cellulose triacetate film generating no longitudinal and lateral wrinkles and excellent in surface quality. SOLUTION: In a method for producing a cellulose triacetate film by a soln. casting film forming method, in a drying process having at least two drive rolls and a large number of free rolls between a start point and a terminal point, the draw ratio of a cellulose triacetate film (web) between the drive rolls is set to 1.00-1.05 in such a state that the residual solvent of the web is 20 wt.% or less and the surface temp. of the web becomes 80 deg.C or higher and the feed tension of the web in the drive roll at the start point of the drying process is set to 10 kgf/m or more and the total contact time of the fed web and the free rolls in the drying process is set to 10 sec or more to feed the web.