Method to prepare superhydrophobic surfaces on solid bodies by rapid expansion solutions

Abstract

The present invention refers to a method for preparing a superhydrophobic surface on a solid substrate comprising the steps of (a) providing a solvent in the form of a pressurized fluid in a vessel, wherein the fluid exhibits a decrease in solvency power with decreasing pressure; (b) adding a hydrophobic substance to the solvent as a solute, which substance is soluble with the pressurized fluid and has the ability to crystallize/precipitate after expansion of the fluid, thereby obtaining a solution of the solvent and the solute in the vessel; (c) having at least one orifice opened on the vessel, thereby causing the pressurized solution to flow out of the vessel and depressurize in ambient air or in an expansion chamber having a lower pressure than within the vessel, the solute thereby forming particles; and (d) depositing the particles on the substrate in order to obtain a superhydrophobic surface. Hereby, a pressurized fluid which expands rapidly as a result of depressurization is used to prepare the superhydrophobic surface, thereby facilitating the preparation of the surface. Moreover, the invention refers to an arrangement for preparing a superhydrophobic surface on a substrate, a superhydrophobic film prepared by the method of the invention, and a substrate having deposited thereon the superhydrophobic firm.