Process for the multi-layer lacquer coating of substrates

Abstract

A process is described for the multi-layer lacquer coating of a substrate by applying a base lacquer layer of an aqueous coating composition onto the optionally precoated substrate and subsequently overcoating with a clear lacquer, which contains: A) at least one copolymer containing hydroxyl groups which is obtainable by reacting a) one or more esters of aliphatic saturated monocarboxylic acids branched in .alpha.-position with one or more epoxide groups in the alcohol portion with b) one or more alkyl esters of .alpha., .beta.-ethylenically unsaturated carboxylic acids, c) one or more hydroxyalkyl esters of .alpha., .beta.-ethylenically unsaturated carboxylic acids, d) optionally one or more .alpha., .beta.-ethylenically unsaturated carboxylic acids and e) optionally one or more vinyl monomers differing from a), b), c) and d), B) one or more polyisocyanates with an average of at least 1.5 NCO groups per molecule in a quantity such that the equivalent ratio of OH groups in component A) to NCO groups of component B) is 1:1.6 to 1:2.2, C) one or more solvents, optionally together with one or more customary lacquer additives.

Dependencies are inferred from the claim text.