| 摘要 |
PROBLEM TO BE SOLVED: To obtain a protective film for a polarizing plate excellent in durability by improving the dimensional stability and the deformation resistance of a cellulose triacetate film at elevated temperature and high humidity. SOLUTION: This cellulose ester film shows <=20 in curl number in term of absolute value determined under the conditions described below and also contains a phthalic ester-based plasticizer at 1-7wt.% based on the cellulose ester. The cellulose ester film is used as a member for liquid crystal display. Conditions: The film sample is left to stand under the atmosphere of 80 deg.C and 90% RH for 48h, cut to 50mm×2mm in the transverse direction and in the lengthwise direction, respectively, moisture-conditioned under the atmosphere of 23±2 deg.C and 55% RH for 24h, and then provided for the determination of the curl number of the film by use of a curvature scale.
|
