The invention relates to an adhesive that can be produced from an aqueous polyurethane urea dispersion, containing an amorphous polyurethane urea, which can be obtained by reacting at least A) an aliphatic polyisocyanate component having an average isocyanate functionality of = 1.8 and = 2.6； B) a polymeric polyether polyol component； C) an amino-functional chain extender component having at least two isocyanate-reactive amino groups, containing at least one amino-functional compound C1) that has no ionic or ionogenic groups, and/or an amino-functional compound C2) that has ionic or ionogenic groups； D) optionally, further hydrophilizing components that are different from C2)； E) optionally, hydroxy-functional compounds having a molecular weight of 62 to 399 mol/g； F) optionally, further polymeric polyols that are different from B)； G) a compound that has exactly one isocyanate-reactive group, or a compound that has more than one isocyanate-reactive group, wherein only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the selected reaction conditions； and H) optionally, an aliphatic polyisocyanate component having an average isocyanate functionality of >； 2.6 and = 4, wherein together, the components B) and F) contain = 30 wt% of component F) based on the total mass of components B) and F). The invention further relates to an adhesive layer and to a product comprising the adhesive, to a method for producing the adhesive layer, to a special polyurethane urea, and to the use of the adhesive.
