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:
Dec. 09, 2014
Filed:
Nov. 17, 2011
Applicants:
Michael Bock, Ruppertsberg, DE;
Kai Thiele, Antwerp, BE;
Heiner Schelling, Kirchheim, DE;
Inventors:
Assignee:
BASF SE, Ludwigshafen, DE;
Primary Examiner:
Int. Cl.
CPC ...
C07C 263/00 (2006.01); C07C 263/10 (2006.01); C07C 263/20 (2006.01);
U.S. Cl.
CPC ...
C07C 263/10 (2013.01); C07C 263/20 (2013.01);
Abstract
The invention relates to a process for preparing methylenedi(phenyl isocyanate), which comprises (a) the phosgenation of two-ring and/or multiring methylenedi(phenylamine), (b) the fractionation of the crude methylenedi(phenyl isocyanate) obtained to give two-ring and multiring isomers, (c) the purification and/or fractionation of the resulting mixture of two-ring isomers of methylenedi(phenyl isocyanate) and (d) the storage of the mixtures obtained in step (c) or in step (b), wherein part of the stored mixtures is reused by means of recirculation in at least one of steps (b) or (c).