| 摘要 |
PROBLEM TO BE SOLVED: To provide a cellulose acylate film contributing to the optical compensation of a thinned VA-mode liquid crystal display device, and to provide a method for producing the cellulose acylate film. SOLUTION: The cellulose acylate film comprises a cellulose acylate meeting the relationships: 2.1≤A+B≤2.4 and 0.8≤B≤1.1 (wherein A is the substitution degree of acetyl groups; and B is the substitution degree of propionyl groups), and is 30-50μm in thickness,≤0.2% in haze, 40-80 nm in Re(590), and 100-300 nm in Rth(590). The method for producing the cellulose acylate film includes: a heating step, in the condition of holding both ends of a long-length cellulose acylate raw film parallel to its longitudinal direction, of heating the film at T<SB>1</SB>°C (wherein 190°C≤T<SB>1</SB>≤240°C); and a widening step, after the heating step, of bringing the resultant raw film to T<SB>2</SB>°C (wherein T<SB>2</SB><T<SB>1</SB>), and widening its length (width) of the direction rectangular to its longitudinal direction (transverse direction) by a factor of 1.3-1.6 while keeping it at T<SB>2</SB>°C. COPYRIGHT: (C)2010,JPO&INPIT |
