METHOD FOR MANUFACTURING STRETCHED FILM

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a stretched film by which a quater wavelength phase plate of a wide band can be formed at a low cost from a single material without requiring formation of layers, and a stretched film having negative wavelength dependence of retardation, excellent transmitting property for rays and no haze can be obtained. SOLUTION: A film having 90 to 350 nm retardation at 550 nm wavelength is manufactured by preparing a sheet by molding a vinyl alicyclic hydrocarbon polymer resin and having <=50 nm retardation at 550 wavelength and stretching the above sheet in at least one direction by 1 to 4 times of elongation magnitude in the temperature range of Tg±50 deg.C with respect to the glass transition temperature (Tg) of the vinyl alicyclic hydrocarbon polymer resin.