Patent ID: 6043332
Filing Date: 2000-03-28
Classification: C08G,C08K

Abstract:
A process for the production of a polyisocyanate containing uretdione groups bya) oligomerizing a portion of the isocyanate groups of a diisocyanate having aliphatically and/or cycloaliphatically bound isocyanate groups in the presence of a catalyst which accelerates the dimerization of isocyanate groups and in the presence of a trisubstituted phosphite stabilizer corresponding to formula (I) ##STR4## wherein R.sup.1, R.sup.2 and R .sup.3 are the same or different and represent a linear or branched aliphatic radical optionally containing ether groups or an aromatic or araliphatic radical having up to 18 carbon atoms, or R.sup.1 and R.sup.2 form a heterocyclic 5- or 6-membered ring together with the phosphorus atom and two oxygen atoms, provided that at least one of the substituents R.sup.1, R.sup.2 or R.sup.3 represents an aromatic radical having 6 to 18 carbon atoms or a linear or branched aliphatic radical having 9 to 18 carbon atoms,b) optionally termination of the oligomerization reaction at a degree of oligomerization of 10 to 60% by adding a catalyst poison andc) optionally removing unreacted diisocyanate by extraction or thin-layer distillation.