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:
Jul. 01, 1986
Filed:
Feb. 21, 1985
Applicant:
Inventors:
Berthold Keggenhoff, Krefeld, DE;
Enno Mahlmann, Krefeld, DE;
Willi Eifler, Bergisch-Gladbach, DE;
Gunther Ellendt, Krefeld, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560347 ; 560359 ; 564333 ;
Abstract
The present invention is directed to a process for the production of polyamines of the diphenylmethane series having a high diamine content and a low 2,2'-diamino-diphenylmethane content by condensing aniline with formaldehyde in the presence of hydrochloric acid as catalyst, neutralizing the acid catalyst at the end of the condensation reaction and working up the polyamine mixture thus obtained by distillation, characterized in that