Cathodically depositable electrodeposition coating baths comprising surface-improving additives, and use of the additives in coating processes

摘要

Aqueous electrodeposition coating baths containing cathodically depositable binders and having a content of homopolymers or copolymers of an alkyl vinyl ether, characterized in that the baths contain the following surface-improving additives:PP0.1 to 5 wt. % of one or more homopolymers or copolymers of an alkyl vinyl ether with 1 to 5 carbon atoms in the alkyl radical and having a weight average molecular weight of 500 to 10000, together withPP 0.1 to 2 wt. % of one or more polyesters comprising &bgr;-hydroxyalkyl ester groups, with an acid number of 0 to 3 and a weight average molecular weight of 1000 to 10000,PPthe percentages by weight relating to the solids in the binders, and the proportions by weight of alkyl vinyl ether homopolymers or copolymers to polyester being in the ratio 1:10 to 10:1, relative in each case to the resin solids.