Patent ID: 9575214
Date: 2017-02-21
CPC Classifications: B32B,C08J,G02B,Y10T

Claim:
1. A method for producing a polarizer including a polyvinyl alcohol-based resin layer, the method comprising in order the steps of: (A) stretching a polyvinyl alcohol-based resin layer to obtain a stretched layer including crystallized portions and non-crystallized portions of polyvinyl alcohol; (B) immersing the stretched layer in a dyeing solution containing iodine for a time period sufficient to obtain a dyed layer in which iodine is adsorbed to said crystallized portions of polyvinyl alcohol in the form of polyiodine complex as well as to said non-crystallized portions to provide an absorbance thereof determined from a tristimulus value Y is from 0.4 to 1.0, wherein the dyed layer has a thickness ranging from 0.4 microns (μm) to about 7 μm; and (C) preferentially removing a part of iodine adsorbed to the non-crystallized portions in the dyed layer to reduce the absorbance, determined in step B, of the dyed layer by 0.03 to 0.7, and preventing the absorbance of the dyed layer from becoming less than 0.3.