| 摘要 |
PROBLEM TO BE SOLVED: To provide a casting roll for producing an optical film which is excellent in retardation uniformity by preventing the contact between the casting roll and the end of a touch roll and pressing the thin film part of a film-shaped molten material extruded on the surface of the casting roll, an apparatus for producing the optical film, and a method for producing the optical film. SOLUTION: With the use of the casting roll having a press part for pressing the thin film part of the film-shaped molten material and non-press parts which are positioned at both ends of the press part and do not press the film-shaped molten material, while the thick film part of the end part of the extruded film-shaped molten material is released, only the thin film part is pressed. The outside diameter of the press part is constant in the entire width, and the outside diameter of the non-press part is smaller than the outside diameter of the press part. COPYRIGHT: (C)2008,JPO&INPIT
|
