| 摘要 |
PURPOSE: A manufacturing method of a cellulose ester film is provided to uniformize the thickness of a film and to minimize the property deviation of the film in the longitudinal and lateral direction after the process of biaxial elongating by adjusting the residual solvent content of the rear end belt to from 15 to 30 weight%. CONSTITUTION: A manufacturing method of a cellulose ester film comprises the following steps: a step of applying a sheet-shaped undiluted solution of casting by pressing to the surface of a belt(30) through a die(20); and a step of evaporating solvent which is in the undiluted solution of casting. In a rear end belt process, the content of residual solvent is between 15 and 30 weight%. The vertical and horizontal tensile strength of the cellulose ester film is 80 n/mm^2 or more and the film thickness deviation of the cellulose ester film is 0.1-2μm. |
