ACRYLIC POLYMER FOR USE IN PRESSURE-SENSITIVE ADHESIVE COMPOSITION FOR TOUCH PANEL

An object of the present invention is to solve the above-mentioned problem of the prior art and provide a pressure-sensitive adhesive composition that has high transparency, excellent adhesion to various substrates such as glass, acrylic, polycarbonate, and PET, as well as having satisfactory high-temperature durability and moist-heat resistance, that is non-corrosive to transparent conductive thin films such as ITO, and to thin metal films, the non-corrosiveness being an important property required of pressure-sensitive adhesives especially for capacitive touch screen panels, and that has excellent gap-filling ability and has high permittivity. Another object of the invention is to provide a pressure-sensitive adhesive sheet. Provided is an acrylic polymer for use in a pressure-sensitive adhesive composition for a touch screen panel, the acrylic polymer being obtained by copolymerizing monomer components comprising (a) a (meth)acrylic acid ester monomer having a C 1-12 hydrocarbon group, (b) a hydroxy group-containing (meth)acrylic acid ester monomer, (c) an amide group-containing monomer, and (d) a vinyl ester monomer. The acrylic polymer has an acid value of 0.1 mg KOH/g or less, a weight-average molecular weight of 400,000 to 2,000,000, a Tg of -80 to 0ºC, and a permittivity of 3 to 6.