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:
May. 12, 2026
Filed:
Dec. 09, 2021
Covestro Deutschland Ag, Leverkusen, DE;
Christos Karafilidis, Leverkusen, DE;
Marina Reithmeier, Cologne, DE;
Stefan Wershofen, Mönchengladbach, DE;
Michael Schedler, Leverkusen, DE;
Michael Baecker, Korschenbroich, DE;
Covestro Deutschland AG, Leverkusen, DE;
Abstract
The present invention relates to a process for preparing a polyisocyanate, namely an isocyanate group-terminated polyol polyanthranilic acid ester. The process comprises the step of reacting an anthranilic acid derivative selected from anthranilic acid halide (in particular anthranilic acid chloride), isatoic anhydride or a mixture thereof with a first polyol of a number-average molar mass of at least 200 g/mol and a functionality in the range of 2 to 8, and obtaining, as a result, a polyamine (namely a polyol polyanthranilic acid ester with amine terminal groups) and reacting the polyamine with phosgene and obtaining, as a result, a polyisocyanate (namely an isocyanate group-terminated polyol polyanthranilic acid ester). The invention further relates to the polyisocyanates obtained in this way, their use in polyaddition reactions, and polyaddition products obtainable by these reactions.