Abstract: The invention relates to water-dispersible polyisocyanate mixtures which is the reaction product of A) a lacquer polyisocyanate having a uretdione, isocyanurate, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione group and prepared from monomeric diisocyanates and B) a polyalkylene oxide polyether containing at least one carboxylic acid group, wherein the polyalkylene oxide polyether is linked to the lacquer polyisocyanate through a reaction between an isocyanate group and a carboxylic acid group to form an acylated urea group or an amide bond. The invention further relates to a process for their preparation and their use as a starting component in the preparation of polyurethane plastics, in particular as crosslinking agents for water-soluble or -dispersible lacquer binders or binder components with isocyanate-reactive groups.