To provide a cellulose ester film having small phase difference value and hardly causing light leakage even when drawn, to provide an optical film, a polarizing plate and a liquid crystal display device, and to provide a method of producing the cellulose ester film.
The cellulose ester film comprises a polymer obtained by polymerizing a cellulose ester satisfying following formula (1) and (2) with an ethylenically unsaturated monomer, wherein at least one of the monomers has nitrogen atom, and in-plane retardation Ro and thickness directional retardation Rt of the film are in the following ranges: formula (1) 2.70X+Y2.95, formula (2) 0.5Y2.3, Ro10 nm, and -20 nmRt20 nm (wherein, X represents a substitution degree of the acetyl group; and Y represents a substitution degree of the propionyl group or the butyryl group).
SAITO KOICHI
YAMADA RUMIKO
| JP2007264480A | 2007-10-11 | |||
| JP2007279083A | 2007-10-25 |
| WO2007108347A1 | 2007-09-27 |
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