Adhesive layer for optical film, optical film having adhesive layer, image display device, and detachment method for optical film

摘要

A pressure-sensitive adhesive layer for an optical film made from an aqueous dispersion-type pressure-sensitive adhesive composition, wherein the aqueous dispersion-type pressure-sensitive adhesive composition is an aqueous dispersion comprising a water-dispersible (meth)acryl-based copolymer (A) having a glass transition temperature from −55° C. to less than 0° C.; and a water-soluble or water-dispersible component (B) having a glass transition temperature of 0° C. or more, a mixture ratio (A)/(B) is in the range of 50-97/3-50, the component (B) forms domains with maximum lengths between 1 nm and 200 nm in a resin component made of the (meth)acryl-based copolymer (A), and the pressure-sensitive adhesive layer has a haze value (H20) of 1% or less when having a thickness of 20 μm. The pressure-sensitive adhesive layer for an optical film, which is made from an aqueous dispersion-type pressure-sensitive adhesive composition has good reworkability or recyclability, and has a sufficient level of durability.

主权项

1. A pressure-sensitive adhesive layer for an optical film made from an aqueous dispersion-type pressure-sensitive adhesive composition, wherein
the aqueous dispersion-type pressure-sensitive adhesive composition is an aqueous dispersion comprising a water-dispersible (meth)acryl-based copolymer (A) containing an alkyl(meth)acrylate and a carboxyl group-containing monomer as monomer units and having a glass transition temperature from −55° C. to less than 0° C. (wherein the glass transition temperature is calculated based on monofunctional monomers for monomer units); and a water-soluble or water-dispersible component (B) having a glass transition temperature of 0° C. or more, a difference of the glass transition temperatures between the (meth)acryl-based copolymer (A) and the component (B) is 50° C. or more, a mixture ratio (A)/(B) (on a solid weight basis) of the (meth)acryl-based copolymer (A) and the component (B) is in the range of 50-97/3-50, the component (B) forms domains with maximum lengths between 1 nm and 200 nm in a resin component made of the (meth)acryl-based copolymer (A), and the pressure-sensitive adhesive layer has a haze value (H20) of 1% or less wherein the haze value (H20) is a haze of the pressure-sensitive adhesive layer with a thickness of 20 μm; wherein the component (B) is a water-soluble resin.