Coating Composition for Low-Refractive Index Anti-Reflection Film

Abstract

A coating composition comprising zeolite nanocrytals, a zeolite precursor solution, and wetting agents in a mixture of solvents is provided. The coating composition can be used to form a transparent layer having a low refractive index on a substrate for antireflection effect.

1 . A method for preparing a coating composition that produces low refractive index anti-reflection film, comprising the following steps:
 preparing a zeolite precursor sol;   preparing a zeolite nanocrystals colloid containing a plurality of zeolite nanocrystals;   mixing the zeolite nanocrystals with the zeolite precursor sol to form a coating mixture.   
     
     
         2 . The method according to the  claim 1 , further comprising adding a solvent into the coating mixture after the mixing step. 
     
     
         3 . The method according to the  claim 1 , wherein the zeolite precursor sol is prepared by adding tetraalkoxysilanes to an aqueous solution of tetraalkylammonium hydroxide. 
     
     
         4 . The method according to the  claim 1 , wherein the molar ratio of tetraalkylammonium hydroxide to tetraalkoxysilanes is 0.17-0.6. 
     
     
         5 . The method according to the  claim 1 , further comprising concentrating the zeolite precursor sol to a solid content of 20%-40% by weight after the step of preparing the zeolite precursor sol. 
     
     
         6 . The method according to the  claim 5 , further comprising heating the concentrated zeolite precursor sol at 40-100° C. after the concentrating step. 
     
     
         7 . The method according to the  claim 5 , further comprising diluting the concentrated zeolite precursor sol after the concentrating step. 
     
     
         8 . The method according to the  claim 1 , wherein the zeolite nanocrystals have a particle size of from 40 nm to 100 nm. 
     
     
         9 . The method according to the  claim 1 , wherein the step of preparing the zeolite nanocrystals colloid comprises a heating process at a temperature of 150° C. to 250° C. 
     
     
         10 . The method according to the  claim 1 , wherein the zeolite nanocrystals are selected from the group consisting of silica zeolite, aluminum silicate zeolite and titanium silicate zeolite having MFI or BEA zeolite structure.