UV-curable waterborne polyurethane dispersions for soft touch coatings

A radiation-curable, aqueous polyurethane emulsion prepared by a process comprising:

• A) reacting
• 1) from about 5 to about 45% by weight of an hydroxy group containing, unsaturated polyester acrylate having an OH number of from about 40 to about 200,
• 2) from about 5 to about 60% by weight of a polycarbonate diol having an OH number of from about 28 to about 225,
• 3) from about 10 to about 20% by weight of a polyether diol having an OH number of from about 28 to about 225, with the proviso that if component 3) is present, the weight ratio of component 2) to component 3) is from about 0.5:1 to about 25:1,
• 4) from about 2 to about 8% by weight of a monohydroxy hydrophilic polyether,
• 5) from about 1 to about 8% by weight of one or more mono- or difunctional isocyanate-reactive compounds that contain moieties selected from cationic groups, anionic groups, potential cationic groups and potential anionic groups, with
• 6) from about 10 to about 30% by weight of one or more diisocyanates and/or polyisocyanates,
• B) optionally converting any potential cationic or anionic groups into cationic or anionic groups by salt formation, and
• C) forming a dispersion of the reaction product of 1), 2), 3), 4), 5) and 6) in water and reacting said dispersion with
• 7) from about 0.1 to about 3% by weight of one or more diamines and/or polyamines,
• wherein the weight percents of components 1) through 7) total 100% and the equivalent ratio of the isocyanate groups in component 6) to the sum of the isocyanate-reactive groups in component 1), 2), 3), 4) and 5) is from about 1.2:1 to about 2.0:1.