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. 23, 2014
Filed:
Jul. 15, 2010
Heiner Schelling, Kirchheim, DE;
Hans-juergen Pallasch, Kallstadt, DE;
Eckhard Stroefer, Mannheim, DE;
Jon S. Speier, Baton Rouge, LA (US);
Byoung-yeon Kim, Baton Rouge, LA (US);
Heiner Schelling, Kirchheim, DE;
Hans-Juergen Pallasch, Kallstadt, DE;
Eckhard Stroefer, Mannheim, DE;
Jon S. Speier, Baton Rouge, LA (US);
Byoung-Yeon Kim, Baton Rouge, LA (US);
BASF SE, Ludwigshafen, DE;
Abstract
The present invention accordingly provides a process for preparing light-colored polyphenylene-polymethylene polyisocyanates comprising the steps (a) providing an amount of chlorine, (b) separating the chlorine provided in the step (a) to obtain a first chlorine fraction having a content of free and bound bromine and iodine of <50 ppm and a second chlorine fraction having an increased content of free and bound bromine and iodine that depends on the original amount of bromine and iodine in the chlorine provided in step (a) and the separation split, (c) reacting carbon monoxide with at least a portion of the first chlorine fraction to form a first phosgene fraction, (d) reacting carbon monoxide with at least a part of the second chlorine fraction to form a second phosgene fraction, (e) reacting at least a portion of a first phosgene fraction with at least one amine of the diphenylmethane diamine series (MDA) to form the corresponding polyphenylene-polymethylene polyisocyanate (PMDI), and (f) reacting at least a portion of the second phosgene fraction with at least one primary amine with the exception of mono- and polyphenylene-polymethylene polyamines to form an at least one isocyanate-containing reaction solution.