Patent ID: 7744953

Claim:
A method for forming a self-cleaning coating on a substrate, comprising the steps of: forming a coating material by providing micro or nano-particles; treating the micro or nano-particles with a hydrophobic agent and an additive to form larger particles with the hydrophobic agent and the additive bonded thereto, wherein the step of treating the micro or nano-particles with the additive and the hydrophobic agent is effected at a pH of about 6.5-14, and wherein the additive promotes hydrolysis and condensation reactions of the micro or nano-particles such that the micro or nano-particles grow into the larger particles; and attaching a binder or crosslinker to the larger particles by reacting the binder or crosslinker with at least one of the additive, the hydrophobic agent, and the particles; applying the coating material to the substrate; and drying or curing the coating material to form a solid coating having a microstructured, hydrophobic surface, wherein the hydrophobic surface of the coating is such that water forms a contact angle of at least 130°.