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:
Jun. 23, 2020
Filed:
Sep. 24, 2018
Applicant:
Covestro Deutschland Ag, Leverkusen, DE;
Inventors:
Thomas Knauf, Dormagen, DE;
Stefan Wershofen, Mönchengladbach, DE;
Klaus-Gerd Gruner, Duisburg, DE;
Volker Hartjes, Duisburg, DE;
Assignee:
Covestro Intellectual Property GmbH & Co. KG, Leverkusen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 209/78 (2006.01); C08G 73/02 (2006.01); C07C 211/50 (2006.01);
U.S. Cl.
CPC ...
C07C 209/78 (2013.01); C08G 73/0266 (2013.01);
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.