Process for preparation of di- and polyamines of the diphenylmethane series

US10689323B2 · kind B2 · utility

Assignee

• Covestro Intellectual Property GmbH & Co. KG · DE

Inventors

• Thomas Knauf · Dormagen, DE
• Stefan Wershofen · Mönchengladbach, DE
• Klaus-Gerd Gruner · Duisburg, DE
• Volker Hartjes · Duisburg, DE

Key dates

• Filing date: Sep 24, 2018
• Grant date: Jun 23, 2020
• Expiry date: Jan 12, 2039

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G73/0266
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a method for the preparation of di- and polyamines of the diphenylmethane series, care being taken during the shutdown of the production process that an excess of aniline and respect to formalin is ensured.