To provide a phase difference film excellent in the durability against a temperature change, and particularly achieving both the reciprocal wavelength dispersibility and the durability.

The phase difference film contains components (A), (B). The component (A) is a cellulose acylate satisfying formula (1), 2.20≤DSac (A)+DSay (A)≤2.90. DSac (A) is the substitution degree of an acetyl in the component (A). DSay (A) indicates the total of the substitution degree due to an acyl group of a carbon number of 3 or 4 in the component (A). The component (B) is a cellulose acylate with the residual degree of 0.30 or more of a hydroxyl group having the viscosity-average polymerization degree different from the component (A).

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