Optical layered body, polarizer and image display device

Abstract

The present invention provides an optical layered body having excellent antistatic properties, optical characteristics, hardness, adhesion, and interference fringe prevention performance, which can be produced at a low cost. An optical layered body having a hard coat layer provided on a triacetylcellulose substrate, wherein a resin composition used for forming the hard coat layer contains a quaternary ammonium salt-containing polymer, a binder resin, and a solvent; the quaternary ammonium salt-containing polymer has a higher hydrophilicity than the binder resin; and the binder resin contains two or more resin components having different hydrophilicities.

1 . An optical layered body comprising a hard coat layer provided on a triacetylcellulose substrate,
 wherein a resin composition used for forming the hard coat layer contains a quaternary ammonium salt-containing polymer, a binder resin, and a solvent,   the quaternary ammonium salt-containing polymer has a higher hydrophilicity than the binder resin, and   the binder resin contains two or more resin components having different hydrophilicities.   
     
     
         2 . The optical layered body according to  claim 1 ,
 wherein the quaternary ammonium salt-containing polymer is a copolymerized product of a dimethylaminoethyl methacrylate quaternary ammonium salt and a (meth)acrylate compound at a mass ratio of 1/99 to 90/10.   
     
     
         3 . The optical layered body according to  claim 1 ,
 wherein the quaternary ammonium salt-containing polymer is contained in an amount of 1.0 to 10% by mass in the solids content of the resin composition.   
     
     
         4 . The optical layered body according to  claim 1 ,
 wherein the two or more resin components having different hydrophilicities are a monomer having a weight-average molecular weight of 600 or less and an oligomer having a weight-average molecular weight of 1,000 to 10,000, and the hydrophilicity of the monomer is higher than that of the oligomer.   
     
     
         5 . The optical layered body according to  claim 4 ,
 wherein the monomer having a weight-average molecular weight of 600 or less includes at least one selected from the group consisting of pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, polyester tri(meth)acrylate, polyester di(meth)acrylate, isocyanuric acid ethylene oxide-modified tri(meth)acrylate, isocyanuric acid ethylene oxide-modified di(meth)acrylate, polyester ethylene oxide-modified tri(meth)acrylate, ethylene oxide-modified di(meth)acrylate, and propylene oxide-modified di(meth)acrylate, and   the oligomer having a weight-average molecular weight of 1,000 to 10,000 is a urethane(meth)acrylate.   
     
     
         6 . The optical layered body according to  claim 1 ,
 wherein the solvent contains two or more solvents having different hydrophilicities.   
     
     
         7 . The optical layered body according to  claim 1 ,
 wherein the solvent contains a penetrating solvent having an ability to penetrate the triacetylcellulose substrate.   
     
     
         8 . The optical layered body according to  claim 1 ,
 wherein the optical layered body has a surface resistance value of 1×10 11 Ω/□ or less, and a haze of 0.7% or less.   
     
     
         9 . A polarizer comprising a polarizing element,
 wherein the polarizer comprises the optical layered body defined in  claim 1 , on a surface of the polarizing element.   
     
     
         10 . An image display device comprising the optical layered body defined in  claim 1 , or the polarizer defined in  claim 9  on an outermost surface thereof. 
     
     
         11 . The optical layered body according to  claim 2 ,
 wherein the quaternary ammonium salt-containing polymer is contained in an amount of 1.0 to 10% by mass in the solids content of the resin composition.   
     
     
         12 . The optical layered body according to  claim 2 , wherein the two or more resin components having different hydrophilicities are a monomer having a weight-average molecular weight of 600 or less and an oligomer having a weight-average molecular weight of 1,000 to 10,000, and the hydrophilicity of the monomer is higher than that of the oligomer. 
     
     
         13 . The optical layered body according to  claim 3 , wherein the two or more resin components having different hydrophilicities are a monomer having a weight-average molecular weight of 600 or less and an oligomer having a weight-average molecular weight of 1,000 to 10,000, and the hydrophilicity of the monomer is higher than that of the oligomer. 
     
     
         14 . The optical layered body according to  claim 2 , wherein the solvent contains two or more solvents having different hydrophilicities. 
     
     
         15 . The optical layered body according to  claim 3 , wherein the solvent contains two or more solvents having different hydrophilicities. 
     
     
         16 . The optical layered body according to  claim 4 , wherein the solvent contains two or more solvents having different hydrophilicities. 
     
     
         17 . The optical layered body according to  claim 5 , wherein the solvent contains two or more solvents having different hydrophilicities. 
     
     
         18 . The optical layered body according to  claim 2 , wherein the solvent contains a penetrating solvent having an ability to penetrate the triacetylcellulose substrate. 
     
     
         19 . The optical layered body according to  claim 3 , wherein the solvent contains a penetrating solvent having an ability to penetrate the triacetylcellulose substrate. 
     
     
         20 . The optical layered body according to  claim 4 , wherein the solvent contains a penetrating solvent having an ability to penetrate the triacetylcellulose substrate.