Waterborne, UV curable coating composition for easy-clean coatings

A waterborne, UV curable coating composition, comprising an aqueous dispersion of a polyurethane and at least one non-fluorinated polymer different from the polyurethane, wherein the polyurethane is present as an additive in an amount 0.1-5 wt. % based on resin solids of the coating composition, and wherein the polyurethane is a carboxyl-functional, unsaturated polyurethane containing a perfluoropolyether block, said polyurethane having a molecular weight Mn in the range from 1,000 to 5,000 determined by gel permeation chromatography with a polystyrene standard and tetrahydrofuran as the mobile phase, said polyurethane prepared by a method comprising the following steps:

• a) subjecting a hydroxy-terminated perfluoropolyether A to a reaction with a molar excess of polyisocyanate B to obtain an isocyanate-functional urethane,
• b) subjecting the isocyanate-functional urethane to a reaction with a carboxyl-functional polyol D to obtain an isocyanate-functional polymer,
• c) subjecting the isocyanate-functional polymer obtained in step b) to a reaction with a mono-OH-functional (meth)acrylate monomer E,
• d) neutralizing the reaction product of step c) with a neutralizer G to obtain a neutralized polyurethane,
• e) dispersing the neutralized polyurethane obtained in step d) in water;
• and wherein the method does not include chain extension with a diamine or a diol after dispersing the neutralized polyurethane in water.