Patent ID: 8747540
Filing Date: 2014-06-10
Classification: C08L,G02B

Abstract:
1. A cellulose ester film comprising at least one plasticizer and satisfying the following expressions (1) to (5): wherein Re represents a retardation value in an in-plane direction; Rth represents a retardation value in a thickness direction; d represents a film thickness; and E′ represents an elastic modulus of the film, wherein the plasticizer is a polycondensed polyester containing an aromatic ring, and wherein the polycondensed polyester satisfies the following (I) and (II): (I) it contains a dicarboxylic acid residue containing an aromatic dicarboxylic acid residue and an aliphatic dicarboxylic acid residue having an average carbon number of from 4.0 to 6.0 and having an aromatic dicarboxylic acid residue ratio as expressed by the following expression of from 40 mol % to 95 mol %: and (II) it contains an aliphatic diol residue having an average carbon number of from 2.0 to 3.0.