Method for dyeing polarizers

Abstract

A polarizing substrate is placed into a dyeing tank for dyeing. A concentration of a dyeing agent in the dyeing tank is less than 800 ppm, and a dyeing period is greater than 200 seconds, so as to improve the dyeing of the polarizing substrate by lengthening the dyeing period and reducing the dyeing agent concentration.

1 . A method for dyeing a polarizing substrate, the method comprising: 
 dyeing a polarizing substrate in a dyeing tank with a dyeing agent, wherein a concentration of the dyeing agent is less than 800 ppm, and a dyeing period is greater than 200 seconds, so as to improve the dyeing of the polarizing substrate by the long dyeing period and the dyeing agent with the low concentration.    
   
   
       2 . The method of  claim 1 , wherein the method further comprises: 
 extending a dyeing path of the polarizing substrate in the dyeing tank to increase the dyeing period.    
   
   
       3 . The method of  claim 2 , wherein the dyeing path extending comprises: 
 extending the dyeing path by a plurality of rollers configured in the dyeing tank.    
   
   
       4 . The method of  claim 2 , wherein the dyeing path extending comprises: 
 extending the dyeing path by increasing a size of the dyeing tank.    
   
   
       5 . The method of  claim 1 , wherein the dyeing agent comprises iodine.  
   
   
       6 . The method of  claim 1 , wherein a material of the polarizing substrate is polyvinyl alcohol.