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. 17, 2012
Filed:
Jun. 30, 2005
Daniel Koch, Duisburg, DE;
Spotswood Miller, Düsseldorf, DE;
Ricardo Serra, Krefeld, DE;
Dietmar Wastian, Dormagen, DE;
Jürgen Kirsch, Leverkusen, DE;
Gerhard Wegener, Mettmann, DE;
Daniel Koch, Duisburg, DE;
Spotswood Miller, Düsseldorf, DE;
Ricardo Serra, Krefeld, DE;
Dietmar Wastian, Dormagen, DE;
Jürgen Kirsch, Leverkusen, DE;
Gerhard Wegener, Mettmann, DE;
Bayer MaterialScience AG, Leverkusen, DE;
Abstract
A two-stage process for the preparation of organic isocyanates by reacting primary amines with phosgene in which: a) in a first stage, amine and phosgene are reacted in an adiabatically managed reaction, in which the temperature of reaction is restricted to values between 100 and 220° C. by actively adjusting the absolute pressure in the reactor to values between 8 and 50 bar by decompression, and the temperature is held at values between 100 and 220° C. until the stoichiometric conversion of phosgene has reached at least 80%; and then b) in a second stage, the reaction mixture from a) is decompressed to an absolute pressure of 1 to 15 bar and the reaction mixture is reacted further at temperatures between 90 and 240° C., optionally with the introduction of heat.