Solvent-based pretreatment agent having improved adhesion to residual adhesive beads

Abstract

A pretreatment composition for adhesive bonds, including i) between 10 and 30 parts by weight of at least one polyurethane polymer PU containing isocyanate groups, obtained from the reaction of at least one poly(meth)acrylate polyol P and at least one polyisocyanate I1, with the proviso that the poly(meth)acrylate polyol P has an OH number of at least 35 and the polyurethane polymer PU has an NCO content of between 2.0% and 25.0% by weight, based on the polyurethane polymer PU; ii) 0.1 to 10 parts by weight of at least one organosilane OS; iii) 0 to 10 parts by weight of at least one further polyisocyanate I2; iv) 60 to 90 parts by weight of a solvent L; v) 0 to 15 parts by weight of an industrial carbon black; vi) 0 to 10 parts by weight of a fumed hydrophobic silica.

Dependencies are inferred from the claim text.