Process for the production of polyisocyanates of the diphenylmethane series by phosgenation of non-neutralized polyamine of the diphenylmethane series

US7041776B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Daniel Koch · Shanghai, CN
• Hans-Georg Pirkl · Leverkusen, DE
• Torsten Hagen · Essen, DE
• Stefan Wershofen · Mönchengladbach, DE

Key dates

• Filing date: Sep 26, 2003
• Grant date: May 9, 2006
• Expiry date: Oct 6, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/10
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a method of producing polyisocyanates of the diphenylmethane series including the steps of