Patent Number: 8,871,969

Title: Process for the production of polyisocyanates

Abstract: The invention provides a multistage process for continuously preparing organic polyisocyanates, preferably diisocyanates, more preferably aliphatic or cycloaliphatic diisocyanates, by reaction of the corresponding organic polyamines with carbonic acid derivatives and alcohols into monomeric polyurethanes of low molecular mass, and the dissociation of said polyurethanes. The invention further provides an associated preparation process in which at certain reaction stages the polyisocyanates prepared and unutilizable residues are removed and reusable by-products and intermediates are recycled to preliminary stages.

Inventors: Mattke; Torsten (Freinsheim, DE), Klotzer; Matthias (Kroppen, DE), Baumann; Robert (Mannheim, DE)

Assignee: BASF SE

International Classification: C07C 263/06 (20060101)

Expiration Date: 2018-10-28 0:00:00