METHOD FOR PRODUCING POLARIZING FILM, AND POLARIZING FILM

摘要

Provided is a method for producing a polarizing film, which comprises: a dyeing step for dyeing a polyvinyl alcohol resin film with a dichroic dye; a crosslinking step for treating the film after the dyeing step with a crosslinking agent; a first stretching step for uniaxially stretching the polyvinyl alcohol resin film during and/or before the crosslinking step; and a second stretching step for uniaxially stretching the film after the crosslinking step in a high-temperature high-humidity atmosphere wherein the temperature is 40-100°C and the absolute humidity is 40 g/m3 or more. Also provided are: a polarizing film which is obtained by having a dichroic dye adsorbed and oriented on a polyvinyl alcohol resin film, and which has a specific TD/MD ratio; and a polarizing plate which comprises this polarizing film.