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. 13, 1994
Filed:
Apr. 21, 1992
Applicant:
Inventors:
Gunter Hammen, Rommerskirchen, DE;
Thomas Schieb, Roesrath, DE;
Stefan Wershofen, Moenchengladbach, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560 25 ; 560 24 ;
Abstract
The present invention relates to an improved process for the production of monomeric and polymeric poly(O-alkylurethanes) of the diphenyl methane series. The process comprises the reaction of the corresponding amines with dialkyl carbonates in the presence of a catalyst, followed by the isolation of the products in a highly pure form. The invention also relates to the use of the produced monomeric and polymeric poly(O-alkylurethanes) for the production of the corresponding isocyanates.