Patent · US Active

Process for producing diamines and polyamines of the diphenylmethane series

US9701617B2 · kind B2 · utility

5Cited by

12References

6Claims

0Family size

Assignee

Covestro Deutschland AG · DE

Inventors

Stefan Wershofen · Mönchengladbach, DE
Heinz Muller · Krefeld, DE
Richard Adamson · Leichlingen, DE
Fritz Pohl · Wittmund, DE
Knut Sommer · Krefeld, DE

Key dates

Filing date	Mar 17, 2009
Grant date	Jul 11, 2017
Priority date	—
Expiry date	Feb 25, 2030

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C263/10
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The present invention relates to a process for producing diamines and polyamines of the diphenylmethane series (MDA) by reacting aniline and formaldehyde in the presence of an acid catalyst, wherein the aniline contains in total less than 0.5 wt. %, based on the total weight of aniline, of one or more compounds which contain at least one carbonyl group or of one or more compounds that are formed by reaction of these compounds which contain at least one carbonyl group with aniline.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.