CELLULOSE ACYLATE FILM, METHOD OF PRODUCING THE SAME, CELLULOSE DERIVATIVE FILM, OPTICALLY COMPENSATORY FILM USING THE SAME, OPTICALLY-COMPENSATORY FILM INCORPORATING POLARIZING PLATE, POLARIZING PLATE AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

A method of producing a cellulose derivative film, the method comprising: forming a film with a solvent cast method from a dope including a cellulose derivative satisfying following conditions (a) and (b): (a) at least one among three hydroxyl groups included in a glucose unit of cellulose is substituted by a substituent of which a polarizability anisotropy ?a represented as following Expression (1) is 2.5-x10^-24 cm³ or higher: Expression (1): ?a =ax- (ay+ az)/2, wherein ax, ay and az is as defined in the specification; and (b) when a substitution degree by a substituent of which ?a is 2.5x10^-24 cm³ or higher is P_A, and a substitution degree by a substituent of which ?a is lower than 2.5x10^-24 cm³ is P_B, the P_A and P_B satisfy following Expressions (3) and (4): Expression (3): 2P_A + P_B > 3.0; and Expression (4): P_A > 0.2.