PRESSURE-SENSITIVE ADHESIVE SHEET

摘要

It is intended to provide a pressure-sensitive adhesive (a pressure-sensitive adhesive sheet) by which the formation of visible bubbles can be prevented even though there are foreign matters on the adherend face in adhesion not only under atmospheric pressure but also under reduced pressure environment. This object can be achieved by proposing a pressure-sensitive adhesive sheet obtained by crosslinking a pressure-sensitive adhesive composition containing a base polymer comprising a (meth)acrylic ester-based copolymer as the main component, an acrylic crosslinkable monomer and a crosslinking initiator, which has such properties that the storage shear modulus of the pressure-sensitive adhesive sheet at a 20<SUP>o</SUP>C standard master curve falls within the range of 5x10<SUP>2</SUP> Pa or higher but not higher than 1x10<SUP>4</SUP> Pa at both of the frequencies of 10<SUP>-3</SUP> Hz and 10<SUP>-5</SUP> Hz, i.e., a pressure-sensitive adhesive sheet wherein crosslinking has been conducted so that the storage shear modulus thereof falls within the range as defined above.