THIN FILM FORMING METHOD, OPTICAL FILM, POLARIZING PLATE AND IMAGE DISPLAY DEVICE

摘要

PURPOSE: To provide a method which is suitable for continuous treatment and uniformly forms a multilayer thin film at a low cost and to provide an optical film with a thin film formed on the surface by the method, a polarizing plate and an image display device using the optical film. CONSTITUTION: In the thin film forming method, the surface of a substrate film whose rear face has a coefficient of dynamic friction of <=0.9, a substrate film having >=1.4x10¬2 N/mm¬2 tensile strength, a substrate film having <=4% water content or a substrate film obtained by drawing a web in the width direction after peeling from a metallic support, is subjected to plasma discharge treatment while feeding a reactive gas to the gaps among electrodes disposed under atmospheric pressure or under a pressure close to atmospheric pressure.