| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming a polarizing film having excellent optical characteristics.SOLUTION: In the method for forming the polarizing film, uniaxial stretching is carried out by making use of a circumferential speed difference between two nip rolls before or during processes in which swelling treatment, dyeing treatment, boric acid treatment and washing treatment to a polyvinylalcohol-based film 10 are carried out in this order. In this case, a stretching process is performed immediately before the boric acid treatment process, the stretching process conducting the uniaxial stretching by means of the two nip rolls 3, 3' which are arranged in air and in liquid in this order while dipping a film in the same treating liquid 4 as the boric acid treatment process, and the rate of decrease of the film width after the dipping in the stretching process is made to be at most 6% with respect to the film width immediately before the dipping. |
