摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cellulose acylate film having high in-plane retardation and a low Rth/Re and to provide a method for producing the same. <P>SOLUTION: The cellulose acylate film includes at least a cellulose acylate satisfying 2.0≤A+B≤2.45, 0.8≤A≤1.4 and 0.6≤B≤1.65 (A is the degree of substitution of acetyl groups for hydroxyl groups of a glucose unit of the cellulose acylate and B is the degree of substitution of an acyl group having ≥3 number of carbons for hydroxyl groups of a glucose unit of the cellulose acylate) and satisfies 50 nm≤Re(590)≤70 nm, 100 nm≤Rth(590)≤120 nm and 1.4≤Rth(590)/Re(590)≤2.6. The method for producing the cellulose acylate film includes a step of flow-casting and drying a solution formed by dissolving the cellulose acylate in a solvent to form a flow-cast film and a step of peeling the flow-cast film having 10 to 75 mass% residual solvent amount. <P>COPYRIGHT: (C)2011,JPO&INPIT |