Abstract: The invention relates to an aqueous binder dispersion for physically drying coating agents, which contains a mixture ofA) 20-80 wt. % of one or more, carbonate group-containing polyurethanes with a number average molecular weight (Mn) of 70,000 to 500,000 in the form of an aqueous dispersion, andB) 20-80 wt. % of one or more carbonate group-free and preferably urea group-free polyurethane resins containing ionic groups, with a number average molecular weight (Mn) of 10,000 to 300,000 and an acid value of 5 to 50, in the form of an aqueous dispersion,the wt. % of the components A) and B), in each case referred to the resin solids, amounting to 100%.