Self-adhesive compound and use thereof in an adhesive tape

Abstract

A self-adhesive compound comprising a) at least one elastomer, at least one type of polybutadiene block copolymer being used as an elastomer, b) at least one partially hydrogenated hydrocarbon resin having a softening temperature of at least 90° C., c) at least one additional hydrocarbon resin, a terpene phenol resin and/or a colophonium resin having a softening temperature of at least 90° C., d) a soft resin, and e) additional additives as applicable.

1 . A pressure-sensitive adhesive at least comprising
 (a) at least one elastomer, the elastomer having a fraction of at least 40 wt %, based on the adhesive composition, and elastomer used comprising at least one kind of a polybutadiene block copolymer,   (b) at least one partly hydrogenated hydrocarbon resin (resin kind 1) having a softening temperature of at least 90° C.,   (c) optionally at least one further hydrocarbon resin, a terpene-phenolic resin and/or a rosin having a softening temperature of at least 90° C. (resin kind 2),   (d) optionally a plasticizing resin,   (e) optionally further additives.   
     
     
         2 . A pressure-sensitive adhesive at least comprising
 (a) at least one elastomer, the elastomer having a fraction of at least 40 wt %, based on the adhesive composition, and elastomer used comprising at least one kind of a polybutadiene block copolymer,   (b) at least one nonhydrogenated hydrocarbon resin (resin kind 1) having a softening temperature of at least 90° C.,   (c) at least one further at least partly hydrogenated or disproportionated hydrocarbon resin, terpene-phenolic resin and/or rosin having a softening temperature of at least 90° C. (resin kind 2),   (d) optionally a plasticizing resin,   (e) optionally further additives.   
     
     
         3 . The pressure-sensitive adhesive of  claim 1 , wherein
 the tan δ of the pressure-sensitive adhesive at application temperature (here 25° C.) at 10 rad/s is at least 0.20 and at 100 rad/s is at least 0.40, and   preferably at application temperature (here 25° C.) at 10 rad/s is not more than 0.40 and at 100 rad/s is not more than 1.00.   
     
     
         4 . The pressure-sensitive adhesive of  claim 1 , wherein
 the fraction of the polybutadiene block copolymer or of the mixture of different polybutadiene block copolymers in the elastomer is at least 90 wt % (based on the total elastomer amount).   
     
     
         5 . The pressure-sensitive adhesive of  claim 1 , wherein
 at least one polybutadiene block copolymer is a triblock copolymer or a higher multiblock copolymer having at least two A blocks.   
     
     
         6 . The pressure-sensitive adhesive of  claim 1 , wherein
 the polybutadiene block copolymers have a polyvinylaromatic fraction of 20 wt % to 40 wt %.   
     
     
         7 . The pressure-sensitive adhesive of  claim 1 , wherein
 the fraction of the polybutadiene block copolymers, in total, based on the overall pressure-sensitive adhesive, is at least 40 wt %, and the maximum fraction of the polybutadiene block copolymers, in total, based on the overall pressure-sensitive adhesive, is not more than 60 wt %.   
     
     
         8 . The pressure-sensitive adhesive of  claim 1 , wherein
 elastomer used comprises an elastomer mixture consisting of A-B-A triblock copolymer and A-B diblock copolymer, the fraction of A-B-A triblock copolymer, based on the total amount of elastomer used, being at least 50 wt %.   
     
     
         9 . The pressure-sensitive adhesive of  claim 1 , wherein
 the total tackifying resin content in the pressure-sensitive adhesive is at least 30 wt %, and not more than 60 wt %.   
     
     
         10 . The pressure-sensitive adhesive of  claim 1 , wherein
 the fraction of resin kind 1 is at least 25 wt % and not more than 60 wt % (based on the adhesive composition).   
     
     
         11 . The pressure-sensitive adhesive of  claim 1 , wherein
 the fraction of plasticizing resin or plasticizing resin mixture is between 0 wt % and 6 wt %, based on the total adhesive composition.   
     
     
         12 . A single- or double-sidedly bonding adhesive-sheet strip, which is optionally carrier-free and hence of only single-ply configuration, comprising the pressure-sensitive adhesive of  claim 1 . 
     
     
         13 . A method for bonding an article to a hydrophilic surface wherein said article is bonded to said hydrophilic surface with an adhesive-sheet strip of  claim 12 . 
     
     
         14 . A bonded assembly comprising the adhesive strip of  claim 12 , the adhesive strip being bonded between two substrates, of which at least one is transparent and/or one substrate is designed in such a way that a load can be affixed thereto. 
     
     
         15 . The pressure-sensitive adhesive of  claim 2 , wherein the fraction of tackifying resin kind 1 is at least 15 wt % and not more than 30 wt % (based on the adhesive composition).