POLARIZING FILM, POLARIZING PLATE AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

A polarizing film which comprises a polyvinyl alcohol based resin film and iodine being adsorbed thereon and oriented, and is prepared, for example, by subjecting the polyvinyl alcohol based resin film to a dyeing treatment, to a stretching treatment, to a boric acid treatment and further to a complementary color treatment in which the film is immersed in a solution containing a chlorine-containing compound. The polarizing film is so adjusted as to have a boric acid content of 5 to 40 wt % by the dyeing treatment, stretching treatment and boric acid treatment, and also to have a chlorine ion content of 200 to 10,000 ppm by the complementary color treatment. The above polarizing film retains an achromatic color when it is arranged at a parallel Nicol position, and also exhibits improved durability of its optical characteristics under a high temperature and high humidity condition and a high temperature condition.