| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical film excellent in developing property of a retardation value and showing little changes in a retardation value in a thickness direction of the film by changes in humidity, and to provide a polarizing plate and a liquid crystal display device including the optical film, which are excellent in durability such as moisture heat resistance.SOLUTION: The optical film comprises at least a cellulose ester and a compound having a function of increasing a retardation value. The optical film has an in-plane retardation value Ro(590) ranging from 30 to 150 nm and a retardation value Rt(590) in a thickness direction ranging from 70 to 300 nm. When relative humidity is changed from 20 to 80%, a change amount (&Dgr;Rt(590)) of the retardation value Rt(590) in the thickness direction ranges from 0 to 10 nm. |
