| 摘要 |
PCT No. PCT/EP87/00130 Sec. 371 Date Sep. 23, 1988 Sec. 102(e) Date Sep. 23, 1988 PCT Filed Mar. 7, 1987 PCT Pub. No. WO87/05922 PCT Pub. Date Oct. 8, 1987.The invention relates to aqueous electrocoating baths for cathodic paint deposition which contain, as cathodically depositable binders, modified epoxide-amine adducts and are prepared by reacting, in the presence of basic amine catalysts, (1) (A) polyepoxides with (B) compounds which contain, per molecule, one or more, preferably 2, hydroxyl groups bonded to aromatic and/or (cyclo)aliphatic molecular fragments, to form epoxide group-containing intermediates, and (2) by subsequently reacting these intermediates, if appropriate, with further conventional modifiers and finally with (C) primary and/or secondary (poly)amines or their salts and/or salts of tertiary amines, the resultant reaction products being neutralized with acids, if appropriate, dispersed in an aqueous medium and these dispersions further processed by well-known methods to form electrocoating baths. The electrocoating baths according to the invention are distinguished by the fact that the basic amine catalyst which catalyzes the reaction between the components (A) and (B) is neutralized, prior to further reaction of the intermediates formed from the components (A) and (B), with a Brönsted acid having a pKs value of the first stage of dissociation, measured at 20 DEG C., below 3.7, preferably below 3.5. |
