Aqueous two-component polyurethane coating compositions

US6204323A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Christian Wamprecht · Neuss, DE
• Hans-Josef Laas · Odenthal, DE

Key dates

• Filing date: May 14, 1999
• Grant date: Mar 20, 2001
• Expiry date: May 14, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31551
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a coating composition containing PA0 A) 30 to 99 wt. % of an aqueous hydroxy- and/or amino-functional resin dispersion and PA0 B) 1 to 70 wt. % of a water dispersible polyisocyanate mixture prepared from aliphatic, cycloaliphatic, araliphatic and/or aromatic diisocyanates and having PA1 a) an average isocyanate functionality of at least 2.0, PA1 b) a content of 5.0 to 25.0 wt. %, based on resin solids, of isocyanate groups (calculated as NCO; molecular weight=42) and PA1 c) a content of 2 to 50 wt. %, based on resin solids, of ethylene oxide units calculated as C.sub.2 H.sub.4 O; molecular weight 44) incorporated within polyether chains containing an average of 5 to 35 ethylene oxide units, wherein at least 60 mole % of the polyether chains are connected via allophanate groups to two polyisocyanate molecules which are each prepared from at least two diisocyanate molecules. The present invention also relates to the use of these coating compositions for preparing coatings, primers and sealing compositions, in particular for automotive refinish and original equipment manufacture.