| 摘要 |
: Aqueous electrocoating baths for cathodic electrocoating and preparation thereof The invention relates to aqueous electrocoating baths for cathodic electrocoating which contain, as cathodically depositable binders, modified epoxide-amine adducts and have been prepared by reacting (1) (A) Polyepoxides and (B) Compounds which contain one or more, preferably 2, hydroxyl groups bonded to aromatic and/or (cyclo)aliphatic molecule fragments per molecule, in the presence of basic amine catalysts to form epoxycontaining intermediates and (2) subsequently reacting these intermediates optionally with further customary modifiers and finally with (C) primary and/or secondary (poly)amines, neutralizing the reaction products thus obtained with acids, dispersing the products in an aqueous medium and further processing this dispersion into electrocoating baths using well-known methods. The electrocoating baths according to the invention are distinguished by the fact that the reaction products formed from (A), (B) and (C) were dispersed in an aqueous medium before the neutralization with acid and subsequently the dispersion thus obtained had added to it at least one anion exchanger which is reactive toward chloride ions and which was separated off on conclusion of the exchange reaction. |
