Method of producing multilayer color and/or effect paint systems utilizing self-crosslinking graft copolymers of polyurethane

US7198824B1 · kind B1 · utility

Assignee

• BASF COATINGS GMBH · DE

Inventors

• Stephan Schwarte · Münster, DE
• Egon Wegner · Munster, DE
• Harald Angermüller · Würzburg, DE

Key dates

• Filing date: Oct 9, 2000
• Grant date: Apr 3, 2007
• Expiry date: Mar 31, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2666/14
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to a method for producing chromophore and/or effect giving multilayer lacquers according to the wet-on-wet method. A water base lacquer is applied which contains at least one graft copolymer containing (A) at least one (meth)acrylate copolymer and (B) at least one polyurethane. The graft copolymer can be produced by (1) dispersing at least one hydrophilic or hydrophobic self cross-linking polyurethane (B) with a statistical average of at least one terminal and/or at least one lateral olefinically unsaturated group and at least one blocked isocyanate group per molecule in an aqueous medium. (2) A mixture of a at least one monomer (a1) with at least one isocyanate reactive functional group at last one monomer (a2) that can be copolymerized therewith is subsequently radically copolymerized in an emulsion in the presence of the polyurethane (B) or the polyurethanes (B). A powder slurry transparent lacquer layer is added to the resulting base lacquer layer. The base lacquer layer and the transparent lacquer layer are hardened together. The invention also relates to novel hydrophilic or hydrophobic self cross-linking polyurethanes (B) with at least one lateral and/o…