RETARDATION FILM, OPTICAL LAMINATE, LIQUID CRYSTAL DISPLAY DEVICE, AND CELLULOSE ESTER FILM

摘要

PROBLEM TO BE SOLVED: To provide a retardation film that can keep linearity of a pattern in a retardation region even when laminated with an optical element such as a polarizing film, an optical laminate and a liquid crystal display device including the retardation film, and a cellulose ester film used as a support of the retardation film.SOLUTION: The retardation film includes a cellulose ester film and a retardation layer in which strip-like retardation regions different from each other are alternately arranged in the layer plane. The cellulose ester film shows an acoustic velocity of 2.7 to 5.0 km/s in a longitudinal direction in the strip-like retardation region and a ratio of (loss modulus)/(storage modulus) of 0.010 to 0.050 at 80°C in the longitudinal direction of the strip-like region. The optical laminate and the liquid crystal display device include the above retardation film; and the cellulose ester film is used for a support of the above retardation film.SELECTED DRAWING: None