Pressure sensitive adhesive composition and a pressure sensitive adhesive tape

Abstract

A pressure sensitive adhesive is obtained by polymerizing a mixture containing: (1) 100 mass parts of (meth)acrylic monomer comprising 98-50 mass parts of a first monomer selected from an aliphatic (meth)alkyl acrylate having a carbon number of 4-6 and an aliphatic (meth)alkyl acrylate having a carbon number of 7-12, wherein the glass transition temperature of a homo-polymer thereof is −25 degrees C. or less; and 2-50 mass parts of a second monomer comprising one or more selected from the group consisting of: an amide group-containing ethylenic unsaturated copolymerizing monomer, a carboxylic group-containing ethylenic unsaturated copolymerizing monomer, an amino group-containing ethylenic unsaturated copolymerizing monomer, a non-tertial alkyl(meth)acrylate wherein the glass transition temperature of a homo-polymer thereof is −25 degrees C. or more; and a monomer represented by the chemical structural formula (I) CH2═CR1COO(R2O)nR3 or CH2═CR1COOR4R5 (R1methyl or H; R2 and R4=linear or branched alkyl having a carbon number of 1-6; R3=methyl, ethyl, or substituted or non-substituted phenyl; R5=substituted or non-substituted 4-membered or 5-membered ring containing oxygen; n=1-16); (2) 10-100 mass parts of a block copolymer; (3) 20-100 mass parts of hydrogenated tackifier; and (4) 0.05-1.0 mass parts of a photopolymerization initiator

Dependencies are inferred from the claim text.