A two-component polyurethane adhesive comprising a polyol component, which contains 2 to 30 wt. % of at least one polyester diol having a molecular weight greater than 1000 g/mole, 5 to 35 wt. % of at least one 3 to 14 functional polyol, 5 to 35 wt.-% hydrophobic polyols, 2 to 65 wt. % further additives or auxiliary agents, wherein the sum is to result as 100%, and a cross-linking component made of polyisocyanates in a NCO/OH ratio of 0.9:1 to 1.5:1, wherein the cross-linked adhesive has a Tg greater than 50 DEG C.