US Patent 7363729 Manufacturing method of optical film, and optical film

A washing process to sufficiently remove contaminants attached on the surface of an optical film is proposed. Specifically, disclosed is a method of manufacturing an optical film, wherein the method possesses the steps of spraying onto at least one surface of a transparent film a solidified blast material via cooling that is a gas or a liquid at normal temperature and pressure, washing the at least one surface of the transparent film, and coating at least one optically functional layer on the washed surface of the transparent film.