The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 01, 2020
Filed:
Oct. 10, 2019
Applicant:
Covestro Deutschland Ag, Leverkusen, DE;
Inventors:
Stefan Wershofen, Mönchengladbach, DE;
Richard Adamson, Leichlingen, DE;
Georg Pirkl, Leverkusen, DE;
Assignee:
Covestro Deutschland AG, Leverkusen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 209/78 (2006.01); C07C 209/86 (2006.01);
U.S. Cl.
CPC ...
C07C 209/78 (2013.01); C07C 209/86 (2013.01);
Abstract
The invention relates to a process for the preparation of di- and polyamines of the diphenylmethane series (MDA), in which firstly crude MDA is prepared and is then subjected to a distillation process, wherein the distillation process comprises the following: