Patent ID: 8911873

Claim:
An ultraviolet cross-linkable pressure sensitive adhesive sheet comprising: a (meth)acrylic copolymer of a monomer containing a (meth)acrylic acid ester having an ultraviolet cross-linkable site, wherein the ultraviolet cross-linkable site has a benzophenone structure, wherein the storage modulus of the pressure sensitive adhesive sheet before ultraviolet cross-linking is from 5.0×10 4 to 1.0×10 6 Pa at 30° C. and 1 Hz and 5.0×10 4 Pa or less at 80° C. and 1 Hz, and wherein the storage modulus of the pressure sensitive adhesive sheet after ultraviolet cross-linking is 1.0×10 3 Pa or more at 130° C. and 1 Hz.