| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method and manufacturing apparatus of optical film, wherein in the manufacturing method of optical film by a solution casting film forming method, the staining of metal powder produced due to wearing of a back surface of a metal endless belt support is sufficiently cleaned to prevent secular degradation of a metal roller, and variance in film thickness due to vibration of the belt support, and generation of gas, are remarkably reduced to improve the working rate of the manufacturing apparatus of the optical film, and reduction in thickness of protective film for polarizing plate, etc., increase in width, and high quality which are requested in recent years, are satisfactorily attained by increasing the productive capacity. SOLUTION: In the manufacturing method of optical film, a magnetic force generation device is set in proximity to the back surface of the metal endless belt support (non-contact surface of a web) and/or the surface of a roller for rotating the belt support, the staining of metal powder stuck and deposited to the back surface of the support and/or the surface of the roller is adsorbed and removed by a magnetic force generated from the magnetic force generation device and, thereby, the back surface of the support and/or the surface of the roller is cleaned. As the magnetic force generation device, a permanent magnet or an electromagnet, especially, a solenoid electromagnet is preferably used. COPYRIGHT: (C)2009,JPO&INPIT |
