Method for producing polyene-based polarizing film (film), polyene-based polarizing film, laminated polarizing film, and display device

摘要

PROBLEM TO BE SOLVED: To provide a method for preparing a polyene-based polarizing film that is new and improved and gives transmitted light to be closer to white light while maintaining high levels of transmittance and polarization degree, and a polyene-based polarizing film, a laminate polarizing film, and a display device.SOLUTION: In one aspect of the present invention, the method for preparing a polyene-based polarizing film includes steps of: producing a dehydrated film by subjecting a polyvinyl alcohol film to a dehydration reaction using an acid catalyst; producing a hydrated film by impregnating the dehydrated film with a hydrating aqueous solution having a pH of 4.0 or less at 85°C or higher for 0.5 to 60 minutes; producing a hydrated dyed film by immersing the hydrated film in a boric acid dye bath; and subjecting the hydrated dyed film to wet orientation in an acidic aqueous solution at 65°C or lower.