Polyisocyanate mixtures, a process for their production and their use for the production of polyurethanes

US5464921A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Hans-Josef Laas · Odenthal, DE
• Reinhard Halpaap · Odenthal, DE
• Christian Wamprecht · Neuss, DE
• Hans-Ulrich Meier-Westhues · Leverkusen, DE
• Wolfgang Schultz · Krefeld, DE
• Lothar Kahl · Bensberg, DE

Key dates

• Filing date: Nov 22, 1993
• Grant date: Nov 7, 1995
• Expiry date: Nov 22, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D251/34
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to polyisocyanate mixtures which are solid below 40.degree. C. and liquid above 125.degree. C. and which have PA1 a) an average isocyanate functionality of at least 2.1, PA1 b) a content of free isocyanate groups bonded to tertiary (cyclo)aliphatic carbon atoms (calculated as NCO; molecular weight=42) of 5 to 22 wt. %, PA1 c) a urethane group content calculated as --NH--CO--O--; molecular weight=59) of 2 to 30 wt. %, PA1 d) an isocyanurate group content (calculated as C.sub.3 N.sub.3 O.sub.3 ; molecular weight=126) of 0 to 30 wt. % and PA1 e) a carboxylic acid ester group content (calculated as --CO--O--; molecular weight=44) of 0 to 25 wt. % and/or PA1 f) a carbonate group content (calculated as --O--CO--O--; molecular weight=60) of from 0 to 34 wt. % with the proviso that the total amount of ester groups e) and carbonate groups f) is at least 2 wt. %. The present invention also relates to a process for the production of these polyisocyanate mixtures and to their use for the production of polyurethanes, in particular as the crosslinking component in heat-curable two-component polyurethane powder coatings for coating heat-resistant substrates.