ALEXANDRIA, Va., Oct. 21 -- United States Patent no. 12,441,680, issued on Oct. 14, was assigned to Covestro Deutschland AG (Leverkusen, Germany).
"Method for producing isocyanates" was invented by Joachim Zechlin (Neuss, Germany), Tim Loddenkemper (Dormagen, Germany) and Thomas Bludowsky (Ratingen, Germany).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention relates to a process for preparing an isocyanate comprising the steps of (A) reacting an amine with a stoichiometric excess of phosgene using an aromatic solvent of formula C6H6-XClX, wherein X=1 or 2, (a) as a diluent during the reaction and/or (b) as a means for cooling the reaction mixture formed from the reaction of the amine with ph...