To provide an optical film which is improved in dimensional stability by a solution casting film forming method and in retardation development properties and can obtain high retardation and a method for producing the optical film and to prevent the corner nonuniformity of a liquid crystal display and the occurrence of a frame failure to respond to requirements for thinning, widening, and quality-improving a protective film for a polarizing plate etc., in recent years.
In the method for producing the optical film, after a web (film) stretching process, embossing for drying is applied to both end parts of a film, and an embossed part for drying having uneven parts composed of a large number of projections each having a convex arcuate cross section and recesses each having a concave arcuate cross section in both end parts of the film is given. The film compression residual distortion rate of the embossed part for drying is made to be 5-50%. After the film with the embossed part for drying is conveyed and dried by a conveyance roll, the embossed part for drying is cut and removed. Next, embossing for a product is applied to the end part of the film. After an embossed part for the product is given, the film is taken up.
| JP2006249418A | 2006-09-21 | |||
| JP2004143376A | 2004-05-20 |
Einosuke Kishimoto
Akira Watanabe
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