| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of producing an optical film which is based on a melt extrusion film formation method, prevents plastic deformation of an elastic touch roll due to entrainment of a film-like molten material onto a chill roll and thereby achieves excellent flatness without unevenness of pressing.SOLUTION: A method of producing an optical film produces an optical film by using a melt extrusion type film formation apparatus including a melt extrusion portion which extrudes a molten material containing thermoplastic resins containing a cellulose ester resin from a flow casting die as a film-like melt, and a cooling take-off portion having an elastic touch roll and a cast roll. The film formation apparatus has carrying abnormality detection means for optical films and controls the operation condition of the elastic touch roll on the basis of information from the carrying abnormality detection means. |
