Powder coating compositions and their use for coating heat-resistant substrates

US5852101A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Reinhard Halpaap · Odenthal, DE
• Christian Wamprecht · Neuss, DE
• Hans-Joachim Kreuder · Krefeld, DE
• Wolfgang Schultz · Krefeld, DE
• Manfred Bock · Leverkusen, DE
• Rainer Rettig · Amagasaki, JP

Key dates

• Filing date: Oct 27, 1997
• Grant date: Dec 22, 1998
• Expiry date: Oct 27, 2017

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 powder coating composition for the production of non-yellowing flexible coatings which is solid below 30.degree. C. and liquid above 120.degree. C. and contains a mixture of PA1 A) a polyisocyanate component which PA2 i) has a content of blocked isocyanate groups (expressed as NCO, molecular weight=42) of 3.0 to 14.0% by weight, PA2 ii) has a functionality, based on the blocked isocyanate groups, of 1.9 to 2.3 and PA2 iii) and contains at least one .epsilon.-caprolactam-blocked polyisocyanate based on the reaction product of 4,4'-diisocyanatodicyclohexyl methane with a polyol component having an average molecular weight of 90 to 400 and containing at least 50% by weight, based on the weight of the polyol component, of one or more (cyclo)aliphatic diols containing 4 to 12 carbon atoms, PA1 B) a polyol component containing at least one polyhydroxy polyacrylate having an OH number of 40 to 120 and PA1 C) an organotin catalyst for the reaction between hydroxyl groups and blocked isocyanate groups, wherein components A) and B) are present in quantities which correspond to an equivalent ratio of blocked polyisocyanate groups to hydroxyl groups of 0.5:1 …