Patent ID: 7935215

Claim:
Heat-activatedly adhesively bondable substantially two-dimensional element, having a layer of a first adhesive and a layer of a second adhesive, wherein the first adhesive comprises at least a first synthetic nitrile rubber and at least one reactive resin which is capable of crosslinking with itself, with other reactive resins and/or with the at least first synthetic nitrile rubber of the first adhesive, the first synthetic nitrile rubber having an acrylonitrile fraction of more than 20% by weight and less than 50% by weight, based on the total mass of the nitrile rubbers in the first adhesive, the second adhesive comprises a blend of at least second, third and fourth synthetic nitrile rubbers, and at least one reactive resin which is capable of crosslinking with itself, with other reactive resins and/or with at least one of the synthetic nitrile rubbers of the second adhesive, a) the blend being microphase-separated, and having at least three different glass transition temperatures in a differential scanning calorimetry thermogram, b) said at least three glass transition temperatures including an upper glass transition temperature of more than +10° C., a middle glass transition temperature and a lower glass transition temperature of less than −20° C., c) the second nitrile rubber having an acrylonitrile fraction of 35% by weight or more, based on the total mass of the nitrile rubbers in the second adhesive, d) the third nitrile rubber having an acrylonitrile fraction of more than 25% by weight and less than 35% by weight, based on the total mass of the nitrile rubbers in the second adhesive, and e) the fourth nitrile rubber having an acrylonitrile fraction of 25% by weight or less, based on the total mass of the nitrile rubbers in the second adhesive.