The present inventions are a pressure-sensitive adhesive composition comprising a poly(meth)acrylate compound that contains a repeating unit shown by the following formula (1) in its molecule and has a melting point of 50° C. or less; a pressure-sensitive adhesive layer comprising a crosslinked product of the pressure-sensitive adhesive composition; and a pressure-sensitive adhesive sheet comprising the pressure-sensitive adhesive layer and a support, the pressure-sensitive adhesive layer being provided on one side or both sides of the support material.
wherein X
+
and Y
−
represent a combination of a counter cation and a counter anion which may form an ion pair, R represents a hydrogen atom or a methyl group, and A represents a linking group.
本发明涉及一种压敏粘合剂组合物,其包括一种聚(甲基)
丙烯酸酯化合物,其分子中含有以下式(1)所示的重复单元,并具有50℃或更低的熔点;一种压敏粘合层,其包括压敏粘合剂组合物的交联产物;以及一种压敏粘合片,其包括压敏粘合层和支撑材料,压敏粘合层位于支撑材料的一侧或两侧。其中,X+和Y-表示可能形成离子对的反离子和反阴离子的组合,R表示氢原子或甲基基团,A表示连接基团。