METHOD FOR MANUFACTURING LONGITUDINAL UNIAXIAL ORIENTED RETARDATION FILM AND LONGITUDINAL UNIAXIAL ORIENTED RETARDATION FILM

摘要

PPROBLEM TO BE SOLVED: To provide a method for manufacturing a longitudinal uniaxial oriented retardation film by which a relatively thin longitudinal uniaxial oriented retardation film having a uniform in-plane phase difference in a width direction can be obtained, and to provide a longitudinal uniaxial oriented retardation film obtained by the manufacturing method. PSOLUTION: The method for manufacturing a retardation film includes a step of longitudinally uniaxially orienting a long amorphous thermoplastic resin film having a longitudinal direction and a width direction, in the longitudinal direction, wherein the following amorphous thermoplastic resin film is used as an amorphous thermoplastic resin film before orientation: the film having the thickness increasing from both ends to the center in the width direction and a fluctuation amplitude of the thickness profile in the width direction being in the range of 1 to 10% with respect to the average thickness in the width direction. The longitudinal uniaxial oriented retardation film is obtained by the above method. PCOPYRIGHT: (C)2008,JPO&INPIT