PROCESS FOR PRODUCING A MULTI-LAYERED COATING

摘要

The invention relates to a process for the production of multicoat coatings, in which process a pigmented aqueous basecoat coating composition is used which contains as the film-forming material a water-thinnable emulsion polymer. The water-thinnable emulsion polymer is prepared in a two-stage emulsion polymerization. In the first stage a polymer is prepared having a glass transition temperature (T G1) of + 30 to + 110.degree.C. In the second stage a mixture of monomers is polymerized in the presence of the polymer prepared in the first stage, which mixture, polymerized on its own, would give a polymer with a glass transition temperature (T G2) of - 60 to + 20.degree.C. The hydroxyl value of the emulsion polymer is between 2 and 100.