POLYVINYL ALCOHOL-BASED FILM FOR USE IN OPTICS, POLARIZING MEMBRANE, AND POLARIZING PLATE

摘要

PROBLEM TO BE SOLVED: To provide such a polyvinyl alcohol-based film for use in optics for the purpose of manufacturing a polarizing membrane, as is excellent in the extensibility and can give a high polarization performance even if a polarizing membrane is manufactured at a low draw ratio, and moreover as is not broken even if stretched at a high draw ratio in order to increase the productivity. SOLUTION: The polyvinyl alcohol-based film for use in optics, which is formed by film-making a film-forming material containing a polyvinyl alcohol-based resin, is characterized in that the polyvinyl alcohol-based resin comprises a polyvinyl alcohol-based resin (X) [excepting the following polyvinyl alcohol-based resin (Y)] and a polyvinyl alcohol-based resin (Y) having 1,2-diol linkage at the side chain, and in that the polyvinyl alcohol-based film has a degree of swelling in weight (W) of 200-300 wt.%. COPYRIGHT: (C)2009,JPO&INPIT