| 摘要 |
PURPOSE:To obtain a film improved in film forming properties by using a polycarbonate copolymer containing 1-30mol% of a repeating unit shown by formula I and 99-70mol% of a repeating unit shown by formula II. CONSTITUTION:An optical film or sheet is made of a polycarbonate copolymer containing 1-30mol% of a repeating unit shown by formula I and 99-70mol% of a repeating unit shown by formula II. In the formulas, R1, R2, R3, and R4 are hydrogen atom or methyl group and the same or different, and X is 5-10C cycloalkylene group, 7-15C aralkylene group, or 1-5C haloalkylene group. |
