| 摘要 |
Binders for cathodically depositable aqueous coating compositions comprising a basic binder system which is blend or partial reaction product of a basic macromolecular component and an acidic macromolecular component, the ratio between acid and basic binders as expressed by amine value and acid value ranges from 97:3 and 65:35, and included in the coating composition is at least one resin component modified with a compound of the general formula OCN-R[NH-CO-R']n wherein: n is 1-3; R is an aliphatic hydrocarbon radical, or an aromatic or cycloaliphatic nucleus, preferably substituted with alkyl groups, and R' is the moiety of a saturated or unsaturated alcohol; a phenol optionally substituted with alkyl radicals; a cyclic lactam; an aldoxime, a ketoxime; an acetoacetic acid ester, or a hydroxamic acid ester. The coating compositions, in addition to providing excellent cross-linking at normal curing temperatures and providing films with enhanced resistance to corrosion, have improved throwing power.
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