At least partially blocked organic polyisocyanates, a process for their preparation and their use in coating compositions

US5350825A · kind A · utility

Assignees

• BAYER HEALTHCARE LLC · DE
• Miles Inc. · US

Inventors

• Eberhard Konig · Kronberg, DE
• Holger Casselmann · Odenthal, DE
• Frank Kobelka · Leverkusen, DE
• Keith-Allen Foster · Krefeld, DE

Key dates

• Filing date: Nov 23, 1993
• Grant date: Sep 27, 1994
• Expiry date: Nov 23, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/808
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to organic polyisocyanates which have a content of unblocked and blocked isocyanate groups (calculated as NCO) of 5 to 20 wt.%, preferably 7 to 15 wt.%, wherein at least 95%, preferably 100%, of the isocyanate groups are present in blocked form and wherein the blocking agent contains PA1 A) 30 to 70 equivalent-% of diisopropylamine, PA1 B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and PA1 C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B), wherein the percentages of A), B) and C) add up to 100. The present invention also relates to a process for the production of these organic polyisocyanates and their use as crosslinking agents for organic polyhydroxyl compounds in polyurethane coating compositions.