Water-soluble double-component paint composition, the purposes of their preparation method and they

摘要

A water-dilutable (water-thinnable) two-component coating composition containing a) a polyisocyanate component comprising one or more organic polyisocyanates, and b) a polyurethane resin prepared by 1. reacting (A) polyisocyanates with (B) polyols having a mean molecular weight Mn of at least 400, (C) optionally low-molecular-weight polyols and (D) compounds containing at least two groups which are reactive towards isocyanate groups and at least one group which is capable of anion formation, to give a prepolymer containing free NCO groups, and 2. reacting the prepolymer formed in step 1 with at least one of the components: (E) low-molecular-weight polyols carrying no further groups which are reactive towards isocyanate groups, these compounds being employed in excess, (F) compounds which are monofunctional or contain active hydrogen of different reactivity and are different from (E), and optionally (G) compounds which are different from (B), (C), (D), (E) and (F) and contain at least two groups which are reactive with NCO groups. r