OPTICAL FILM AND SOLUTION FILM-FORMING METHOD

摘要

Provided are an optical film having a protective film function and a brightness improving function of a polarizing plate, and a solution film forming method capable of manufacturing the long optical film. The present invention forms a flexible film by continuously stretching a first dope and a second dope on a driving belt and forms a wetting film generated by peeling the flexible film from the belt. A concave part and a convex part are formed on a second layer formed by the second dope of the wetting film by using a formation providing roller. The wetting film is guided to a heating room and a heating process is performed for 15 minutes. The optical film is obtained by the heating process. The obtained optical film includes a cellulose acylate layer (21) and a hardening layer (22). A refractive index of the hardening layer (22) is larger than a refractive index of the cellulose acylate layer (21). A prism sheet (16) is obtained from the optical film.