Microstructured optical films comprising biphenyl difunctional monomers

Abstract

Optical films having a polymerized microstructured surface are described. The polymerized microstructured surface comprises the reaction product of a polymerizable resin composition comprising 10% to 100 wt-% of at least one biphenyl di(meth)acrylate monomer. The di(meth)acrylate monomer comprises a core biphenyl structure having two aromatic rings connected with a C—C bond. The biphenyl di(meth)acrylate monomer preferably comprises a sufficient amount of ortho and/or meta(meth)acrylate substituents such that the monomer is a liquid at 25° C.

1 . An optical film having a polymerized microstructured surface that comprises the reaction product of a polymerizable resin composition comprising 10% to 100 wt-% of at least one biphenyl di(meth)acrylate monomer comprising two aromatic rings connected with a C—C bond wherein the biphenyl di(meth)acrylate monomer is a liquid at 25° C. 
     
     
         2 . An optical film having a polymerized microstructured surface that comprises the reaction product of a polymerizable resin composition comprising 10% to 100 wt-% of at least one biphenyl di(meth)acrylate monomer comprising two aromatic rings connected with a C—C bond and the aromatic rings comprise at least one (meth)acrylate substituent at an ortho or meta position. 
     
     
         3 . The optical film according to  claim 2  wherein the biphenyl di(meth)acrylate monomer has the general structure
 H 2 C═(R1)C(O)—Ar—Ar—(O)C(R1)═CH 2 ; wherein each Ar group is independently phenyl or napthyl and R1 is H or methyl.   
     
     
         4 . The optical film according to  claim 2  wherein each (meth)acrylate group is bonded to an aromatic ring group at an ortho or meta position. 
     
     
         5 . The optical film according to  claim 2  wherein each (meth)acrylate group is bonded to an aromatic ring group at an ortho position. 
     
     
         6 . The optical film according to  claim 2  wherein each (meth)acrylate group is independently bonded to an aromatic ring with a linking group having a molecular weight of less than 1200 g/mole. 
     
     
         7 . The optical film of  claim 6  wherein the linking group is an alkoxy group. 
     
     
         8 . The optical film of  claim 3  wherein the biphenyl di(meth)acrylate monomer has the general structure 
       
         
           
           
               
               
           
         
       
       wherein each R1 is independently H or methyl;
 each R2 is independently Br; 
 m ranges from 0 to 4; 
 each Q is independently O or S; 
 n ranges from 0 to 10; 
 L is a C2 to C12 alkyl group optionally substituted with one or more hydroxyl groups; 
 z is an aromatic ring; 
 t is independently 0 or 1; and 
 and at least one of the -Q[L-O]n C(O)C(R1)═CH 2  groups is substituted at the ortho or meta position. 
 
     
     
         9 . The optical film of  claim 8  wherein Q is O. 
     
     
         10 . The optical film of  claim 8  wherein n is 0, 1 or 2. 
     
     
         11 . The optical film of  claim 8  wherein L is C2 or C3. 
     
     
         12 . The optical film of  claim 8  wherein L is a hydroxyl substituted C2 or C3. 
     
     
         13 . The optical film of  claim 8  wherein each -Q[L-O]n C(O)C(R1)═CH 2  is substituted at the ortho or meta position. 
     
     
         14 . The optical film of  claim 8  wherein each -Q[L-O]n C(O)C(R1)═CH 2  is substituted at the ortho position. 
     
     
         15 . The optical film of  claim 8  wherein z is fused. 
     
     
         16 . The optical film of  claim 8  wherein the biphenyl di(meth)acrylate monomer is non-halogenated. 
     
     
         17 . The optical film of  claim 8  wherein the monomer has the general structure 
       
         
           
           
               
               
           
         
       
     
     
         18 . The optical film of  claim 8  wherein the monomer has the general structure 
       
         
           
           
               
               
           
         
       
     
     
         19 . The optical film according to  claim 2  wherein the monomer has a refractive index of at least 1.55. 
     
     
         20 . An optical film having a polymerized microstructured surface that comprises the reaction product of a polymerizable resin composition comprising
 25 wt-% to 75 wt-% of one or more biphenyl di(meth)acrylate monomers having (meth)acrylate substituents at an ortho or meta position; and   25 wt-% to 75 wt-% of one or more bisphenol A di(meth)acrylate monomers.   
     
     
         21 . The optical film according to  claim 2  wherein the polymerizable resin composition is non-halogenated. 
     
     
         22 . The optical film according to  claim 2  wherein the polymerizable resin is free of inorganic nanoparticles. 
     
     
         23 . The optical film according to  claim 2  wherein the polymerizable resin comprises at least 10 wt-% of surface modified inorganic nanoparticles. 
     
     
         24 . The optical film according to  claim 23  wherein the inorganic nanoparticles comprise zirconia. 
     
     
         25 . The optical film according to  claim 2  wherein the optical film is a brightness enhancing film having a single sheet gain of at least 1.59.