Crosslinked solid type pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet comprising the composition, and pressure-sensitive adhesive sheet for waterproofing/airproofing comprising the sheet

Abstract

A solid type pressure-sensitive adhesive composition capable of being applied without the necessity of using an organic solvent or water and a pressure-sensitive adhesive sheet, which are excellent in both adhesive force and holding power and, in particular, undergo no decrease in low-temperature adhesive force even when the adhesive layer thickness is small. The crosslinked solid type pressure-sensitive adhesive composition comprising (a) a rubbery polymer, (b) a tackifier, and (c) a crosslinking agent comprising at least one member selected from the group consisting of thiuram vulcanizing agents, quinoid vulcanizing agents, quinone dioxime vulcanizing agents, and maleimide vulcanizing agents.

1 . A crosslinked solid type pressure-sensitive adhesive composition comprising (a) a rubbery polymer, (b) a tackifier, and (c) a crosslinking agent comprising at least one member selected from the group consisting of quinoid vulcanizing agents and quinone dioxime vulcanizing agents.  
     
     
         2 . The composition as claimed in  claim 1 , wherein the rubbery polymer (a) is a butyl rubber.  
     
     
         3 . The composition as claimed in  claim 1 , wherein the rubbery polymer (a) is a regenerated butyl rubber.  
     
     
         4 . The composition as claimed in  claim 1 , wherein the rubbery polymer (a) has a Mooney viscosity ML 1+4 (100° C.) of from 20 to 100.  
     
     
         5 . The composition as claimed in  claim 1 , wherein the tackifier (b) is a resin compatible with the rubbery polymer.  
     
     
         6 . The composition as claimed in  claim 1 , wherein the tackifier (b) is used in an amount of from 20 to 200 parts by weight per 100 parts by weight of the rubbery polymer.  
     
     
         7 . The composition as claimed in  claim 1 , wherein the crosslinking agent (c) is used in an amount of from 0.5 to 20 parts by weight per 100 parts by weight of the rubbery polymer.  
     
     
         8 . A pressure-sensitive adhesive sheet comprising a substrate and formed thereover a pressure-sensitive adhesive layer comprising a crosslinked solid type pressure-sensitive adhesive composition comprising (a) a rubbery polymer, (b) a tackifier, and (c) a crosslinking agent comprising at least one member selected from the group consisting of quinoid vulcanizing agents and quinone dioxime vulcanizing agents.  
     
     
         9 . The pressure-sensitive adhesive sheet as claimed in  claim 8 , wherein the pressure-sensitive adhesive layer has a thickness of from 50 to 500 μm.  
     
     
         10 . The pressure-sensitive adhesive sheet as claimed in  claim 8 , which is for use as a pressure-sensitive adhesive sheet for waterproofing and/or airproofing.