Tin-free aqueous polyurethane dispersions

摘要

The present invention relates to radiation-curable coating compositions based on tin-free aqueous polyurethane dispersions based on polyurethane acrylates (i), characterized in that the polyurethane acrylate (i) comprises as builder components;A) one or more compounds with at least one group which is reactive towards isocyanate and at least one unsaturated group which can undergo free radical polymerization,;B) one or more compounds which differ from A) and have at least one group which is reactive towards isocyanate,;C) one or more compounds with at least one group which is reactive towards isocyanate and additionally at least one group having a hydrophilizing action,;D) one or more organic polyisocyanates,;which are reacted in the presence of;F) bismuth(III) salt(s) and;G) an acid having a pKa of <2.5,;and a process for the preparation thereof, the use of the coating compositions as lacquers and/or adhesives, and objects and substrates provided with these lacquers and/or adhesives.

主权项

1. A tin-free, radiation-curable aqueous dispersion based on one or more polyurethane acrylates (i), wherein said one or more polyurethane acrylates (i) is prepared by reacting
A) one or more compounds comprising at least one group which is reactive with isocyanate and at least one unsaturated group which can undergo free radical polymerization; B) one or more compounds which differ from A) selected from the group consisting of monomeric monols, monomeric diols, monomeric triols, oligomeric hydroxy-functional compounds, and polymeric hydroxy-functional compounds, and which comprise at least one group which is reactive with isocyanate; C) one or more compounds comprising at least one group which is reactive with isocyanate and at least one group having a hydrophilizing action; and D) one or more organic polyisocyanates; in the presence of a catalyst comprising F) one or more bismuth(III) salts; and G) an acid having a pKa of less than 2.5.