摘要 |
A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from a pressure-sensitive adhesive composition containing a polyisobutylene-based resin (A) having a mass-average molecular weight of 20000 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 one or more selected from the group consisting of a styrene-butadiene-styrene triblock copolymer (SBS), a styrene-block-(ethylene-co-butylene)-block-styrene triblock copolymer (SEBS), a styrene-isobutylene diblock copolymer (SIB), and a styrene-isobutylene-styrene triblock copolymer (SIBS), has excellent adhesive force, excels in a suppressing effect on moisture intrusion, and has good transparency. |