Patent ID: 7501167
Filing Date: 2009-03-10
Classification: C08B,C08L,C09K,G02B

Abstract:
1. A cellulose acylate film comprising cellulose acylate which has a degree of crystallinity represented by the following expression (I) of from 1.1 to 1.3 and satisfies the following expressions (II) and (III): wherein A represents a substitution degree by an acetyl group of a hydroxyl group in a glucose unit of the cellulose acylate, and B represents a substitution degree by a substituent having from 3 to 4 carbon atoms of a hydroxyl group of a glucose unit of the cellulose acylate, wherein the cellulose acylate film has an in-plane retardation value at a wavelength of 589 nm of from 20 to 80 nm, and a retardation value in a direction of film thickness at a wavelength of 589 nm of from 100 to 200 nm, wherein the cellulose acylate film is manufactured by being stretched at a temperature of higher than a glass transition temperature of the film by from 20° C. to 200° C., wherein the cellulose acylate film is manufactured by being stretched by 10% or more in a direction of film casting or in a direction of casting width.