Binders for cathodic electrocoating

US4713406A · kind A · utility

Assignee

• BASF SE

Inventors

• Eberhard Schupp · Schwetzingen, DE
• Rolf Osterloh · Lechenich, DE
• Werner Loch · Erpolzheim, DE
• Klaas Ahlers · Munster, DE

Key dates

• Filing date: Nov 25, 1986
• Grant date: Dec 15, 1987
• Expiry date: Nov 25, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G59/58
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Binders for cathodic electrocoating which are based on polyadducts/polycondensates which carry basic nitrogen groups and are rendered water-dilutable by protonation with an acid, and one or more crosslinking agents for these polyadducts/polycondensates, their use and electrocoating baths prepared from them. These binders essentially consist of a mixture of PA0 (A) from 50 to 90% by weight of a polyadduct/polycondensate which carries basic nitrogen groups and is obtainable by reacting PA1 (a) an essentially epoxide-free adduct of a secondary amine and polyepoxide compound with PA1 (b) a condensate of a diamine/polyepoxide adduct which is prepared in the presence of excess diamine and separated off from excess diamine after complete conversion of the epoxide groups, with one or more mono- and/or dicarboxylic acids of not less than 6 carbon atoms. PA0 (B) from 10 to 50% by weight of a crosslinking agent which does not react with component (A) at room temperature but reacts with the latter at elevated temperatures with crosslinking. These binders are particularly useful for the cathodic electrocoating of electrically conductive substrates.