Aqueous binders and their use in aqueous coating compositions

US5688859A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Volker Schneider · Sinsheim, DE
• Harald Blum · Wachtendonk, DE
• Armin Sickert · Krefeld, DE

Key dates

• Filing date: Jan 16, 1996
• Grant date: Nov 18, 1997
• Expiry date: Jan 16, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/6254
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for preparing aqueous binders for aqueous coating compositions by reacting a mixture of PA1 A) 9.9 to 85 wt. % of a hydroxy- and acid-functional poly(meth)acrylate and PA1 B) 14.9 to 90 wt. % of a hydroxy-functional, fatty acid-modified polyester with PA1 C) 0.1 to 20 wt. % of a diisocyanate having a molecular weight of 140 to 318, to form urethane groups and then dissolving or dispersing the reaction product in water with prior or simultaneous neutralization of at least a portion of the carboxyl groups present, wherein the sum of the percentages of A) to C) add up to 100. The present invention also relates to the aqueous binders obtained by this process and their use, optionally combined with other oxidatively drying lacquer resins, in air- and/or heat-drying, two-component coating compositions, preferably aqueous polyurethane coating compositions, or in combination with optionally blocked polyisocyanates and/or amino cross-linking agents in aqueous heat-curing coating compositions.