Adhesive sheet, optical component with adhesive layer, and image display device.

Abstract

This provides an adhesive sheet with reduced noise and excellent reliability at high temperatures. [Solution] The adhesive sheet 1 comprises an adhesive layer 10 containing an acrylic polymer. The acrylic polymer has constituent units derived from an alkyl (meth)acrylate (A) having an alkyl group having 4 to 12 carbon atoms, and constituent units derived from an alkyl (meth)acrylate (B) having an alkyl group having 13 to 25 carbon atoms. The mass ratio of the alkyl (meth)acrylate (A) to the alkyl (meth)acrylate (B) [(alkyl meth)acrylate (B) / (alkyl meth)acrylate (A)] is 0.7 to 1.5. The adhesive sheet 1 is used in optical components.

Claims

1. It comprises an adhesive layer containing an acrylic polymer, The acrylic polymer has constituent units derived from an alkyl (meth)acrylate (A) having an alkyl group having 4 to 12 carbon atoms, and constituent units derived from an alkyl (meth)acrylate (B) having an alkyl group having 13 to 25 carbon atoms. An adhesive sheet for use in optical components, wherein the mass ratio of the alkyl (meth)acrylate (A) to the alkyl (meth)acrylate (B) [(alkyl meth)acrylate (B) / (alkyl meth)acrylate (A)] is 0.7 to 1.

5.

2. The adhesive sheet according to claim 1, wherein the alkyl (meth)acrylate (A) comprises an alkyl (meth)acrylate (A1) having a branched alkyl group having 8 to 12 carbon atoms and an alkyl (meth)acrylate (A2) having an alkyl group having 4 to 7 carbon atoms.

3. The adhesive sheet according to claim 1 or 2, wherein the total ratio of the alkyl (meth)acrylate (A) and the alkyl (meth)acrylate (B) to the total amount of monomer components constituting the acrylic polymer is 90% by mass or less.

4. The adhesive sheet according to claim 1 or 2, wherein the (meth)acrylate alkyl ester (B) has a branched alkyl group.

5. The adhesive sheet according to claim 1 or 2, wherein the difference between the number of carbon atoms in the alkyl group of the (meth)acrylate (B) and the number of carbon atoms in the alkyl group of the (meth)acrylate (A1) is 5 or more.

6. The adhesive sheet according to claim 1 or 2, wherein the dielectric loss tangent (tanδ) of the adhesive layer at 70°C is 0.35 or less.

7. The adhesive sheet according to claim 1 or 2, wherein the adhesive layer has a glass adhesive strength of 0.5 N / 10 mm or more on at least one side under conditions of 85°C, 85% RH, peel angle of 180°, and tensile speed of 300 mm / min.

8. An optical member with an adhesive layer, wherein the adhesive sheet described in claim 1 or 2 is attached to at least one side of the optical member.

9. An image display device having an optical member with an adhesive layer as described in claim 8.

10. The image display device according to claim 9, wherein it is a touch panel.

Images