Cellulose ester film, its manufacturing method, polarizing plate, and liquid crystal display

Abstract

A cellulose ester film and its manufacturing method are disclosed, the cellulose ester film comprising a compound represented by the following formula (1) in an amount of from 1 to 30% by weight, wherein Y represents an ester bond or a divalent organic group containing an ester bond, Ra and Rb independently represent a substituent, and m and n independently represent an integer of 0 to 5, provided that when m or n is not less than 2, plural Ras or Rbs may be the same or different.

1 - 20 . (canceled)  
     
     
         21 . A method of manufacturing a cellulose ester film according to a solution cast film manufacturing process, the method comprising the steps of: casting, on a support, a cellulose ester solution comprising a compound represented by the following formula (1) to form a web on the support; drying the web on the support; peeling the web from the support; stretching the peeled web in the transverse direction or in the mechanical direction by a factor of from 1.01 to 2.5; and further drying the peeled web,  
       
         
           
           
               
               
           
         
       
       wherein Y represents an ester bond or —R 1 C(═O)O—, —C(═O)OR 2 —, —C(═O)O—R 3 —OC(═O)— or —OC(═O)—R 4 —C(═O)O—, in which R 1  and R 2  independently represent a substituted or unsubstituted alkylene group, and R 3  and R 4  independently represent a substituted or unsubstituted alkylene group, or —(R 5 O) p R 5 —, in which R 5  represents a substituted or unsubstituted alkylene group, and p is an integer of from 1 to 3; Ra and Rb independently represent an alkyl group, RcC(═O)O— or —C(═O)ORc in which Rc represents a substituted or unsubstituted phenyl group or a substituted or unsubstituted cyclohexyl group; and m and n independently represent an integer of from 0 to 5, provided that when m or n is not less than 2, plural Ras or Rbs may be the same or different.  
     
     
         22 . The method of  claim 21 , wherein the cellulose ester film comprises the compound in an amount of from 1 to 30% by weight.  
     
     
         23 . The method of  claim 21 , wherein the cellulose ester film comprises a UV absorbent having a distribution coefficient or not less than 8.5.  
     
     
         24 . The method of  claim 21 , wherein the cellulose ester film comprises silicon oxide particles.  
     
     
         25 . The method of  claim 21 , wherein the cellulose ester film comprises a cellulose ester having a total acyl substitution degree of from 2.55 to 2.85.  
     
     
         26 . The method of  claim 21 , wherein the cellulose ester film has a thickness of from 10 to 60 μm, a moisture vapor transmittance of from 20 to 200 g/m 2 ·24 hr, and a rate of weight change falling within the range of ±2% in which the rate is represented by the ratio of the difference between the film weights before and after storage at 80° C. and 90% RH for 48 hours to the film weight before the storage.  
     
     
         27 . The method of  claim 21 , wherein the cellulose ester solution contains methyl acetate.  
     
     
         28 . The method of  claim 21 , wherein the cellulose ester film further comprises a matting agent in an amount of from 0.005 to 0.3% by weight.