Dispersions of crosslinked polymer micro-particles in aqueous media, a process for the preparation of these dispersions, and coating compositions containing these dispersions

US5075372A · kind A · utility

Assignee

• Basf Lacke & Farben Aktiengesellschaft · DE

Inventors

• Hans-Dieter Hille · Bensberg, DE
• Horst Muller · Cologne, DE
• Arnold Dobbelstein · Cologne, DE
• Peter Mayenfels · Münster, DE

Key dates

• Filing date: Oct 28, 1988
• Grant date: Dec 24, 1991
• Expiry date: Oct 28, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/4263
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to dispersions of crosslinked polymer micro-particles in aqueous media, which have been prepared: PA0 (1) (a) by dispersing a mixture of the components (A) and (B) in an aqueous medium, the component (A) being composed of one or more polyester-polyols containing at least 2 hydroxyl groups, and the component (B) being composed of one or more polyisocyanate compounds in which the isocyanate groups are at least partially in the masked form, and the components (A) and/or (B) having available a number of ionic groups, preferably carboxylate groups, sufficient to form a stable dispersion, and at least one part of the components (A) and/or (B) containing more than 2 hydroxyl or optionally masked isocyanate, respectively, groups per molecule and PA0 (2) (b) by subsequently heating the dispersion thus obtained to a temperature sufficiently high for the components (A) and (B) to react to form crosslinked polymer micro-particles.