AQUEOUS AND/OR WATER-DILUTABLE POLYISOCYANATE CROSS-LINKING AGENTS WHICH ARE BLOCKED BY A DIISOPROPYLAMINE, AND THE USE OF SAID AGENTS

摘要

Polyisocyanate blocked with diisopropylamine is stable on storage in the aqueous phase and does not undergo constant carbon dioxide emission as occurs, for example, with malonic acid diethyl ester or 1,2,4-triazole blocked polyisocyanate. An aqueous and/or water dilutible blocked polyisocyanate crosslinking agent comprises (equivalent %): (a) polyisocyanate component (100); (b) diisopropylamine (50-80); (c) monohydroxy and/or dihydroxycarboxylic acid as hydrophilizing agent (15-40); and (d) a difunctional HO and/or NH2 group carrying chain lengthening agent (0-15), Where the quantity ratio of the reaction partner is selected so that the equivalent ratio of NCO groups of component (a) to the reactive groups of components (c) and (d) is 1:0.8 to 1:1.2 respectively, and containing additives and adjuvants. An Independent claim is included for preparation of the crosslinking agent from component (a) by reaction of 30 wt. % water-miscible solvent in a first reaction stage at 80 deg C with a hydrophilizing monohydroxycarboxylic acid, with cooling to 50 deg C, and blocking of the residual NCO groups by addition of diisopropylamine