OPTICAL FILMS AND PROCESS FOR PRODUCTION THEREOF

摘要

An optical film which contains little impurities and is excellent in physical properties and surface appearance, produced by melt-extruding an acrylic resin which has a glass transition temperature of 110 to 200°C and a viscosity of 250 to 1000Pa s as determined at a shear rate of 100(1/s) and a resin temperature of 270°C by the use of an extruder provided with either a barrier flight screw or a screw with a mixing section with the cylinder and die of the extruder preset at temperatures lower than the glass transition temperature of the acrylic resin plus 145 (°C); and a process for the production of the film.