Process for the production of very pure 2,4′-methylenediphenyl diisocyanate

US7495124B2 · kind B2 · utility

Assignee

• Bayer MaterialScience AG · DE

Inventors

• Hans-Georg Pirkl · Leverkusen, DE
• Jeffrey Bolton · Mülheim an der Ruhr, DE
• Walter Meckel · Neuss, DE
• Ulrich Wolf · Laax, CH
• Matthias Wintermantel · Bensberg, DE
• Jochen Mahrenholtz · Krefeld, DE

Key dates

• Filing date: Feb 1, 2005
• Grant date: Feb 24, 2009
• Expiry date: Jun 4, 2026

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09J175/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the production of MDI fractions containing 2,4′-MDI, and in which the 2,2′-MDI component from the MDA production is largely removed from the isomer mixture. Highly reactive monomeric MDI products can be produced in this way. These MDI products are characterised in their processing by significantly reduced emissions of MDI monomers.