WATER-BASE COATING COMPOSITION, ITS PREPARATION AND ITS USE IN MULTILAYER LACQUERING METHOD

摘要

Aqueous coating compound containing a polyurethane resin-based binder of I) from 60 to 100% by weight of a mixture of A) from 5-95% by weight of one or more self-emulsifying polyurethane resins in aqueous dispersion having a number average molar mass (Mn) of from 30000 to 300000 and containing carboxyl groups corresponding to an acid number of from 5 to 50, obtainable from a water dispersible polyurethane prepolymer having more than one free isocyanate group per molecule, by chain lengthening with water and B) from 95 to 5% by weight of one or more acrylated polyesters and/or acrylated polyurethanes having an acid number of from 5 to 50 in aqueous dispersion and II) from 0 to 40% by weight of one or more formaldehyde condensation resins and/or blocked polyisocyanates, the percentages by weight being based in each case on the resin solids content. The coating compounds are suitable in particular as basic lacquers for multi-coat lacquering. Coatings with good weather resistance are produced from them.