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:
Jan. 21, 2020
Filed:
Jun. 26, 2017
Applicant:
Covestro Deutschland Ag, Leverkusen, DE;
Inventors:
Assignee:
Covestro Deutschland AG, Leverkusen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 209/78 (2006.01); C07C 211/50 (2006.01); B01J 21/04 (2006.01); B01J 21/08 (2006.01); C08G 12/08 (2006.01); C08G 73/02 (2006.01); C07C 209/54 (2006.01);
U.S. Cl.
CPC ...
C07C 209/78 (2013.01); B01J 21/04 (2013.01); B01J 21/08 (2013.01); C07C 211/50 (2013.01); C08G 12/08 (2013.01); C08G 73/0266 (2013.01); C07C 209/54 (2013.01);
Abstract
The invention relates to a production process for di- and polyamines of the diphenylmethane series by the rearrangement of a condensation product of aniline and a methylene group-supplying agent preferably selected from the group consisting of aqueous formaldehyde solution, gaseous formaldehyde, para-formaldehyde, trioxane and mixtures thereof, wherein said condensation product is reacted in the presence of at least one silica-alumina catalyst, said catalyst having