Production of mixtures of diisocyanates and polyisocyanates from the diphenylmethane series with high contents of 4,4′-methylenediphenyl diisocyanate and 2,4′-methylenediphenyl diisocyanate

US7038002B2 · kind B2 · utility

Assignee

• Bayer MaterialScience AG · DE

Inventors

• Hans-Georg Pirkl · Leverkusen, DE
• Ulrich Liman · Monheim, DE
• Robert Vieler · Dormagen, DE
• Ralf Echterhoff · Dormagen, DE

Key dates

• Filing date: Jul 21, 2004
• Grant date: May 2, 2006
• Expiry date: Jul 21, 2024

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/20
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A fraction of diisocyanates of the diphenylmethane series containing at least 95 wt. % binuclear methylenediphenyl diisocyanate is obtained by