Process for producing a polarizing film

摘要

A polarizing film comprising a polyvinyl alcohol-type film and a dichroic dye, a metallic ion and boric acid incorporated therein, and a process for producing the same, which comprises adsorbing a dichroic dye on a polyvinyl alcohol-type film, stretching the film substantially in one direction, immersing the stretched film in an aqueous solution containing a metallic ion and boric acid.