Polyisocyanates containing ester groups, a process for the production of these polyisocyanates and their use in polyurethane coating compositions

US5096994A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Lutz Schmalstieg · Neunburg vorm Wald, DE
• Josef Pedain · Cologne, DE
• Klaus Nachtkamp · Cologne, DE
• Lothar Kahl · Bensberg, DE
• Manfred Schonfelder · Leverkusen, DE

Key dates

• Filing date: Aug 2, 1990
• Grant date: Mar 17, 1992
• Expiry date: Aug 2, 2010

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/771
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to polyisocyanates which contain ester groups and have PA0 a) a content of aliphatically bound isocyanate groups of 18 to 33% by weight, PA0 b) an average NCO functionality of 4.1 to 10, preferably from 4.5 to 10, and PA0 c) a viscosity of 200 to 2,5000 mPa.s at 22.degree. C. The present invention also relates to preferred polyisocyanates which contain ester groups and have PA0 a) a content of aliphatically bound isocyanate groups of 20 to 33% by weight, PA0 b) an average NCO functionality of 5 to 8 and PA0 c) a viscosity of 500 to 1,000 mPa.s at 22.degree. C. The present invention further relates to a process for the preparation of these preferred polyisocyanates by reacting isocyanatocarboxylic acid chlorides with O-silylated, polyhydric alcohols at a temperature of about 50.degree. to 150.degree. C. Finally, the present invention relates to the use of the polyisocyanates as the isocyanate component for two-component polyurethane coating compositions.