Heat curable coating compositions and their use as top coats

US5532313A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Eberhard Konig · Kronberg, DE
• Theodor Engbert · Recklinghausen, DE
• Josef Pedain · Cologne, DE

Key dates

• Filing date: May 8, 1995
• Grant date: Jul 2, 1996
• Expiry date: May 8, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/4063
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to heat curable coating compositions containing a binder consisting essentially of PA1 A) prepolymers which have butanone oxime-blocked isocyanate groups and are prepared from PA2 A1) (cyclo)aliphatic polyisocyanates and PA2 A2) an organic polyhydroxyl component in which PA3 A2.1 ) 50 to 90% of the hydroxyl equivalents of component A2) are from polyester polyols, PA3 A2.2) 10 to 50% of the hydroxyl equivalents of component A2) are from polyacrylate polyols and/or alkoxylation products of bisphenol A and PA3 A2.3) 0 to 30 of the hydroxyl equivalents of component A2) are from other organic polyhydroxyl compounds, and PA1 B) cycloaliphatic polyamines having at least two primary amino groups, wherein components A) and B) are present in an equivalent ratio of blocked isocyanate groups to amino groups of 1:0.8 to 1:1.2. The invention also relates to the use of these coating compositions for producing decorative, flying-stone-resistant, thick topcoats on metallic substrates.