| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cellulose derivative film having a high retardation Rth in the thickness direction. <P>SOLUTION: The film contains a cellulose derivative which has a polymerization unit represented by the general formula (1) and which satisfies the following expressions (I)-(III); (I) 0≤DS<SB>A</SB>≤1.4, (II) 0<DS<SB>B</SB>, and (III) 0<DS<SB>C</SB>. In the formula (1), R<SP>2</SP>, R<SP>3</SP>, and R<SP>6</SP>each independently represent a hydrogen atom, an unsubstituted aliphatic hydrocarbon group, or an acyl group. In the expressions, DS<SB>A</SB>is the number of hydrogen atoms present as R<SP>2</SP>, R<SP>3</SP>, and R<SP>6</SP>in the unit, DS<SB>B</SB>is the number of unsubstituted aliphatic hydrocarbon groups each present as R<SP>2</SP>, R<SP>3</SP>, and R<SP>6</SP>in the unit, and DS<SB>C</SB>is the number of acyl groups each present as R<SP>2</SP>, R<SP>3</SP>, and R<SP>6</SP>in the unit, wherein DS<SB>A</SB>+DS<SB>B</SB>+DS<SB>C</SB>=3. <P>COPYRIGHT: (C)2009,JPO&INPIT |
