To obtain such an optical film that sufficient performances for both of moisture resistance and optical function holding characteristics are obtd. even when the film is made large in size and that stable adhesion property is obtd. without causing warpage of a liquid crystal cell by applying an adhesive layer having each specified saturation water absorption and adhesion strength against peeling on one or both surfaces of an optical film material.
This optical film is produced by applying an adhesive layer 3 on one or both surfaces of an optical film material 2. This adhesive layer has <0.60wt.% saturation water absorption at 50°C and 90% R.H and ≤600g/20mm adhesion strength against 90° peeling test on the interface with the body adhered of a peeled side. For example, the optical film material 2 consists of an adhesive layer 3, a polarizing film 21 and a phase film 21 and the laminated structure with the adhesive layer 3 constitutes an elliptical polarization film as the optical film material 2. As for the polarizing film 21, such a film is used that is prepared by adsorbing iodine and the like on a hydrophilic polymer film such as a polyvinylalcohol film and ethylene-vinyl acetate copolymer-based partially saponified film and then stretching the film.
KOJIMA KATSUHIDE
OIZUMI SHINICHI
TANAKA YOSHIKAZU
MIYAUCHI KAZUHIKO
YAMAOKA HISASHI
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