Depolluting coating composition
The invention is a coating composition comprising photocatalytic titanium dioxide particles, an opacifying agent, a silicone compound, de-HNO 3 particles, styrene resin hollow microspheres, and a solvent. The combination of a silicone compound and styrene resin hollow microspheres in a depolluting coating composition results in improved opacity and durability compared to conventional coatings.
1 . A coating composition comprising: (a) photocatalytic titanium dioxide particles; (b) an opacifying agent; (c) a silicone compound; (d) de-HNO 3 particles; (e)styrene resin hollow microspheres; and (f) a solvent.
2 . The coating composition of claim 1 wherein the photocatalytic titanium dioxide particles are anatase, rutile or mixtures thereof.
3 . The coating composition of claim 1 wherein the photocatalytic titanium dioxide particles are predominantly anatase.
4 . The coating composition of claim 3 wherein photocatalytic titanium dioxide particles have a mean particle size of between 2 and 100 nm.
5 . The coating composition of claim 1 wherein the photocatalytic titanium dioxide particles are present in an amount ranging from 0.5 to 20%, by weight of the total composition.
6 . The coating composition of claim 1 wherein the opacifying agent is pigmentary titanium dioxide.
7 . The coating composition of claim 1 wherein the silicone compound is a polysiloxane.
8 . The coating composition of claim 1 wherein the de-HNO 3 particles are selected from the group consisting of calcium carbonate, zinc carbonate, magnesium carbonate, and mixtures thereof.
9 . The coating composition of claim 1 wherein the de-HNO 3 particles are calcium carbonate.
10 . The coating composition of claim 1 wherein the styrene resin hollow microspheres are selected from the group consisting of polystyrene, poly-α-methylstyrene, and styrene-acrylic copolymer resins.
11 . The coating composition of claim 1 wherein the styrene resin hollow microspheres are styrene-acrylic copolymer resins.
12 . The coating composition of claim 1 wherein the solvent comprises water.
13 . The coating composition of claim 1 further comprising an organic polymer.
14 . The coating composition of claim 13 wherein the organic polymer is selected from the group consisting of acrylic polymers, polyvinyl acetates, and styrene-butadienes.