Benzyl (meth)acrylate monomers suitable for microstructured optical films

Abstract

Presently described are optical films comprising a polymerized (e.g. microstructured) surface that comprises the reaction product of a polymerizable resin composition and polymerizable resin compositions that comprise nanoparticles; at least one first monomer comprising at least two (meth)acrylate groups; and at least one second (meth)acrylate monomer having the structure wherein at least one R1 comprises an aromatic substituent, t is an integer from 1 to 4, and R2 is hydrogen or methyl.

What is claimed is: 
     
         1 . An optical film comprising a polymerized microstructured surface that comprises the reaction product of a polymerizable resin composition comprising
 nanoparticles;   at least one first monomer comprising at least two (meth)acrylate groups; and   at least one second (meth)acrylate monomer having the structure   
       
         
           
           
               
               
           
         
         wherein at least one R1 comprises an aromatic substituent, 
         t is an integer from 1 to 4, and 
         R2 is hydrogen or methyl. 
       
     
     
         2 . The optical film of  claim 1  wherein t is 1. 
     
     
         3 . The optical film of  claim 1  wherein R1 is selected from the group consisting 
       
         
           
           
               
               
           
         
       
     
     
         4 . The optical film of  claim 1  wherein the monomer has a refractive index of at least 1.54. 
     
     
         5 . The optical film of  claim 1  wherein the monomer has a viscosity of less than 100 cps at 25° C. 
     
     
         6 . The optical film of  claim 1  wherein the first monomer comprises at least two aromatic rings. 
     
     
         7 . The optical film of  claim 6  wherein the first monomer is a bisphenol, fluorene or biphenyl (meth)acrylate monomer. 
     
     
         8 . The optical film of  claim 1  wherein the polymerizable resin comprises up to 15 wt-% of one or more first monomers comprising at least two (meth)acrylate groups. 
     
     
         9 . The optical film of  claim 1  wherein the first monomer comprising at least two (meth)acrylate groups has a molecular weight of at least 350 g/mole. 
     
     
         10 . The optical film of  claim 1  wherein the polymerizable resin composition is non-halogenated. 
     
     
         11 . The optical film of  claim 1  wherein the nanoparticles have a refractive index of at least 1.60. 
     
     
         12 . The optical film of  claim 11  wherein the nanoparticles comprise zirconia. 
     
     
         13 . The optical film of  claim 11  wherein the polymerizable resin comprises at least 40 wt-% nanoparticles. 
     
     
         14 . The optical film of  claim 1  wherein the optical film is a brightness enhancing film. 
     
     
         15 . The optical film of  claim 14  wherein the brightness enhancing film has a single sheet relative gain of at least 1.75. 
     
     
         16 . An optical film comprising a polymerized surface that comprises the reaction product of a polymerizable resin composition comprising
 nanoparticles;   at least one first monomer comprising at least two (meth)acrylate groups; and   at least one second (meth)acrylate monomer having the structure   
       
         
           
           
               
               
           
         
         wherein at least one R1 comprises an aromatic substituent, 
         t is an integer from 1 to 4, and 
         R2 is hydrogen or methyl. 
       
     
     
         17 . A polymerizable resin composition comprising
 nanoparticles;   at least one first monomer comprising at least two (meth)acrylate groups; and   at least one second (meth)acrylate monomer having the structure   
       
         
           
           
               
               
           
         
         wherein at least one R1 comprises an aromatic substituent, 
         t is an integer from 1 to 4, and 
         R2 is hydrogen or methyl.