| abstract |
A polyisobutylene-based resin (A) having a mass average molecular weight of 20,000 or more, a styrene-based copolymer (B), and a tackifier (C) having a softening point of 135°C or less, wherein the component (B) is styrene-butadiene-styrene Triblock copolymer (SBS), styrene-block-(ethylene-co-butylene)-block-styrene triblock copolymer (SEBS), styrene-isobutylene diblock copolymer (SIB) and styrene-isobutylene -The pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed of at least one pressure-sensitive adhesive composition selected from the group consisting of styrene triblock copolymers (SIBS) has excellent adhesion, has an excellent effect of suppressing moisture intrusion, and has good transparency. |