METHOD FOR PRODUCING POLYISOCYANATES HAVING URETDION AND / OR ISOCYANURATE GROUPS, THE POLYISOCYANATES OBTAINED BY THIS METHOD AND THEIR USE IN POLYURETHANIC PAINTS

摘要

A novel process for the preparation of polyisocyanates containing uretdione and/or isocyanurate groups by catalytic oligomerisation of some of the isocyanate groups of organic diisocyanates, discontinuation of the oligomerisation reaction at the desired degree of oligomerisation by oxidative deactivation of the trivalent phosphorus compounds employed as catalysts and distillative removal of the unreacted excess of diisocyanate, the compounds which can be obtained by this process and their use as isocyanate components in polyurethane lacquers.