Patent ID: 7501167

Claim:
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): Degree of crystallinity=(X-ray diffraction intensity at 2θ of 13°)/(X-ray diffraction intensity at 2θ of 12°); Expression (I) 2.6≦ A+B≦ 3.0; and Expression (II) 0.5 ≦B≦ 1.2 Expression (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.