Process for the production of a multicoat coating, aqueous coating compositions, water-thinnable poly-acrylate resins and process for the preparation of water-thinnable polyacrylate resins

US5514746A · kind A · utility

Assignee

• Basf Lacke & Farben Aktiengesellschaft · DE

Inventors

• Stephan Schwarte · Münster, DE
• Manfred Dangschat · Drensteinfurt, DE
• Manfred Reimann · Drensteinfurt, DE
• Carlos Westermann · Munster, DE

Key dates

• Filing date: Oct 30, 1992
• Grant date: May 7, 1996
• Expiry date: Oct 30, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D151/003
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the production of a multicoat coating in which the aqueous topcoat composition contains a water-thinnable polyacrylate resin which has a hydroxyl value of 40 to 200, an acid value of 20 to 100 and a glass transition temperature (T.sub.G) of -40.degree. C. to +60.degree. C., and can be prepared by adding a mixture (I) of a (meth)acrylic acid ester, a copolymerizable hydroxyl-containing monomer and, if appropriate, a further ethylenically unsaturated monomer to an organic solvent and carrying out free-radical polymerization and adding, at the end of the addition of the mixture (I), a mixture of a monomer containing carboxyl groups and a monomer free from carboxyl groups and continuing the polymerization.