Process for coating electrically conductive substrates, aqueous coating composition, process for the preparation of a cationic, amine-modified epoxy resin and cationic, amine-modified epoxy resin prepared according to this process

US5262465A · kind A · utility

Assignee

• Basf Lacke & Farben Aktiengesellschaft · DE

Inventors

• Gunther Ott · Hachenburg, DE
• Ulrich Heimann · Munster, DE
• David J. Santure · Novi, US
• Udo Reiter · Telgte, DE

Key dates

• Filing date: Dec 11, 1991
• Grant date: Nov 16, 1993
• Expiry date: Dec 11, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D163/00
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a cathodic electro-dipcoating process, wherein the electro-dipcoating composition used contains a cationic, amine-modified epoxy resin, which is obtainable by reacting PA1 (A) a polyepoxide, PA1 (B) an amine and PA1 (C) an adduct, which is obtainable by . . . (sic) PA2 (c1) a polyether- or polyester-polyol, PA2 (c2) a polyisocyanate and PA2 (c3) a compound which contains at least one hydrogen atom which is reactive towards isocyanate groups and at least one ketimine group in the molecule, and/or PA1 (D) a hydrolysis product of (C) with one another in a relative proportion such that 20 to 90% of the epoxy groups of component (A) are reacted with component (B) and the remaining epoxy groups are reacted with component (C) and/or (D), and--if still necessary--at least partially protonating the reaction product thus obtained.