| 摘要 |
The present invention addresses the problem of providing a stretched cellulose ester film, and a method for producing the same, whereby cellulose orientation defects are minimized in high-ratio stretching and broadening, and whereby trimming defects are unlikely to occur during high-speed conveyance, with little variance in the retardation value (Ro) in the in-plane direction in various parts of the film. This stretched cellulose ester film contains a cellulose ester that has a degree of acetyl group substitution in the range 2.8-2.95, wherein the stretched cellulose ester film is characterized in that part of the cross-sectional shape of surface (A) of the stretched cellulose ester film in the transverse direction is represented by a catenary curve, and the thickness difference (h) (maximum film thickness -film thickness at the ends) is in the range 1.0-4.0 µm. As used herein, "surface (A)" refers to a surface opposite to the side in contact with a belt surface or a drum surface when a film dope is cast onto a belt or drum to form a film. |
