Polarizing film, laminated film, and liquid crystal display

Abstract

The invention provides a polarizing film comprising: a long polymer film; and a dichroic substance, wherein the polarizing film has an absorption axis in the TD direction of the polarizing film.

1 . A polarizing film comprising: 
 a long polymer film; and    a dichroic substance,    wherein the polarizing film has an absorption axis in the TD direction of the polarizing film.    
   
   
       2 . The polarizing film according to  claim 1 , 
 wherein the length in the MD direction of the polarizing film is not smaller than five times as long as the length in the TD direction of the polarizing film.    
   
   
       3 . The polarizing film according to  claim 1 , 
 wherein the polarizing film is produced by stretching the long polymer film in the TD direction.    
   
   
       4 . The polarizing film according to  claim 1 , 
 wherein the polarizing film is produced by:    stretching the long polymer film in the TD direction; and    shrinking the long polymer film in the MD direction.    
   
   
       5 . The polarizing film according to  claim 1 , 
 wherein the polarizing film is produced by dyeing the long polymer, which is stretched in the TD direction, with a iodine by using an aqueous solution containing the iodine.    
   
   
       6 . The polarizing film according to  claim 1 , 
 wherein the polarizing film is produced by dyeing the long polymer, which is stretched in the TD direction and shrunk in the MD direction, with a iodine by using an aqueous solution containing the iodine.    
   
   
       7 . The polarizing film according to  claim 5 , 
 wherein the polarizing film is produced by dyeing the long polymer film with the iodine by applying the aqueous solution containing the iodine onto the long polymer film.    
   
   
       8 . A laminated film comprising: 
 a polarizing film according to  claim 1;  and    a retardation film having a slow axis in the MD direction, which comprises a long polymer film,    wherein the MD direction of the polarizing film corresponds to the MD direction of the retardation film.    
   
   
       9 . The laminated film according to  claim 8 , 
 wherein the retardation film comprises a uniaxially stretched film.    
   
   
       10 . The laminated film according to  claim 8 , 
 wherein the retardation film comprises an optically uniaxial layer comprising a liquid crystal material.    
   
   
       11 . The laminated film according to  claim 8 , 
 wherein the retardation film comprises a birefringent layer comprising a non-liquid crystal material having a birefringence of not lower than 0.005.    
   
   
       12 . The laminated film according to  claim 8 , 
 wherein the retardation film is a composite film comprising a birefringent layer provided on a birefringent polymer film.    
   
   
       13 . The laminated film according to  claim 11  or  12 , 
 wherein the birefringent layer comprises a solid polymer containing at least one selected from: polyetherketone; polyamide; polyester; polyimide; polyamideimide; and polyesterimide.    
   
   
       14 . The laminated film according to  claim 13 , 
 wherein the birefringent layer is a solid polymer comprising polyimide.    
   
   
       15 . The laminated film according to  claim 11  or  12 , 
 wherein the birefringent layer has a relationship nx>ny>nz,    wherein nx is the maximum in-plane refractive index, ny is an in-plane refractive index in a direction perpendicular to the direction of nx, and nz is a thicknesswise refractive index.    
   
   
       16 . A liquid crystal display comprising a polarizing film according to  claim 1  that is disposed outside of a liquid crystal cell.  
   
   
       17 . A liquid crystal display comprising a laminated film according to  claim 8  that is disposed outside of a liquid crystal cell.  
   
   
       18 . A process for producing a polarizing film comprising: 
 unrolling a polymer film successively;    stretching the polymer film in the TD direction; and    dyeing the stretched film.    
   
   
       19 . The process for producing a polarizing film according to  claim 18;   wherein the stretching in the TD direction is carried out by a tenter stretching machine.