Coating composition and method of making and using the same
The present application is directed to a method of making an article. The method comprises coating a composition to a surface of a substrate. The coating composition comprises an aqueous continuous liquid phase, a silica nano-particle dispersed in the aqueous continuous liquid phase, and a polymer latex dispersion. The coated substrate is then heated to at least 300° C.
1. A method of making an article, the method comprising
providing an aqueous silica nano-particle composition,
providing an alkaline pH stable polymer latex dispersion;
mixing the aqueous silica nano-particle composition with the polymer latex dispersion to create a mixture comprising an aqueous continuous liquid phase comprising at least 50% by weight of water,
adjusting the pH of the mixture to less than 6 to form core-shell particles and create a coating composition,
coating the surface of a substrate with the coating composition;
heating the coated substrate to at least 300° C.,
wherein the coating composition has a pH of less than 6,
wherein the coating composition is capable of regenerating the polymer latex dispersion and the silica nano-particle composition upon raising the pH of the coating composition, and
wherein the coating on the substrate is antireflecting after the heating step.
2. The method of claim 1 wherein the silica nano-particle is a nominally spherical particle.
3. The method of claim 1 wherein the silica nano-particle is an elongated particle.
4. The method of claim 1 wherein the silica nano-particle composition comprises a blend of nominally spherical and elongated silica nano-particles.
5. The method of claim 1 wherein the silica nano-particle is a chain of nominally spherical particles.
6. The method of claim 1 wherein the silica nano-particle is a chain of elongated particles.
7. The method of claim 1 wherein the silica nano-particle is a chain of nominally spherical and elongated particles.
8. The method of claim 1 wherein each core-shell particle comprises a polymer core surrounded by a shell consisting essentially of nonporous nominally spherical silica particles disposed on the polymer core, wherein the nonporous nominally spherical silica particles have a volume average particle diameter of 60 nanometers or less.
9. The method of claim 8 wherein the volume average particle diameter is 20 nanometers or less.
10. The method of claim 1 , wherein the substrate surface comprises a glass panel.
11. The method of claim 10 wherein the glass panel has a flat surface.
12. The method of claim 10 wherein the glass panel has a structured surface.
13. The method of claim 10 comprising adding the coated glass panel to a photovoltaic cell to make a photovoltaic module.
14. The method of claim 1 wherein the coated substrate is heated to at least 400° C.
15. The method of claim 1 wherein the coated substrate is heated to at least 500° C.
16. The method of claim 1 wherein the coated substrate is heated to at least 600° C.
17. The method of claim 1 wherein the coated substrate is heated to at least 700° C.
18. The method of claim 1 wherein the silica nano-particle is nonporous.