Cationic paint binders based on polyether urethanes and process for preparation thereof

摘要

Cationic paint binders based on polyether urethanes are formed by selective reaction of one NCO-group of a diisocyanate which contains NCO-groups of different reactivities with the primary hydroxyl groups of a polyhydroxypolyether in the presence of 1,4-diazabicyclo-2,2,2-octane (DABCO) as catalyst, and subsequently reacting the remaining NCO-group of the diisocyanate with a secondary amine. The binders which are largely free of low molecular basic by-products are used for formulating paints, particularly cathodically depositable electrodeposition paints, which are water-dilutable after protonation.