摘要 |
PROBLEM TO BE SOLVED: To provide a fumaric acid diester-based resin for a film suitable for a retardation film excellent in optical characteristics such as a high out-of-plane retardation even in a thin film and a small wavelength dependence, and to provide a retardation film.SOLUTION: Provided are a fumaric acid diester-based resin for a film contains a fumarate diisopropyl residue unit and a fumaric acid di-tert-butyl residue unit and a retardation film using the same. |