Abstract: The present disclosure relates generally to polyurethane-based coatings with high solar reflectivity, for example, for use as a coating on a building surfaces. In one aspect the disclosure provides a solar reflective coating that comprises a functionalized anionic polyurethane present in an amount in the range of 10-80 wt %, preferably 20-80 wt % of the composition on a dry solids basis; a water-insoluble transition metal crosslinking agent present in an amount in the range of 0.5-30 wt % of the composition on a dry solids basis; and at least one of: a hydrophobic acrylic polymer present in an amount in the range of 20 wt % to 80 wt % on a dry solids basis, and a near-infrared reflective colored pigment present in an amount of at least 0.1 wt %, e.g., in the range of 0.2 wt % to 10 wt % on a dry solids basis.

Abstract: The present invention is drawn to an aqueous polyurethane dispersion comprising: —anionic polyurethane particles comprising both free pending carboxylate groups of formula —COO?M+ where M+ is a cation resulting from neutralization of carboxylic acid groups with a base, and pending carboxylate ester groups resulting from esterification of free carboxylic acid groups with an epoxysilane, —crosslinking particles made of water-insoluble transition metal compounds. It is also drawn to a method of coating a substrate comprising applying such an aqueous polyurethane dispersion onto a substrate and letting it dry, preferably without applying any heat or radiation.