Method for producing polarizing film
AssigneeSumitomo Chemical Company, Limited
InventorsKoji Matsumoto, Narutoshi Hayashi, Nobuyuki Kurata
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Abstract
A method for producing a polarizing film comprising the step of dipping a polyvinyl alcohol film in/on which iodine is adsorbed and oriented in an aqueous solution containing boric acid wherein the aqueous solution has an absorbance of 0.13 or less at a wavelength of 450 nm. The produced polarizing film has a high contrast.
Claims6
A method for producing a polarizing film comprising the step of supplying a polyvinyl alcohol film in/on which iodine is adsorbed and oriented in an aqueous solution containing boric acid and dipping and treating said polyvinyl alcohol film with said aqueous solution, wherein an absorbance of said aqueous solution at a wavelength of 450 nm is maintained in a range of 0.13 or less by continuously or intermittently treating said aqueous solution with activated carbon.
Dependencies are inferred from the claim text.