# US 8,771,806 B2 · Surface coating method for hydrophobic and superhydrophobic treatment in atmospheric pressure plasma > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,771,806 B2 - Document ID: US8771806B2 - Status: Granted - Kind: B2 - Application number: 11/988,442 - Filed: 2006-07-07 - Published: 2010-09-02 - Granted: 2014-07-08 - Earliest claimed: 2005-07-09 - Applicants: Bang-Kwon Kang - Inventors: Bang-Kwon Kang - Web page: https://patentgrep.com/patent/US8771806B2 ## CPC - C23C 16/50: using electric discharges {(generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34)} - B05D 1/62: {Plasma-deposition of organic layers (plasma deposition in general C23C14/00, C23C16/00)} - B05D 5/083: {involving the use of fluoropolymers} - C23C 16/22: characterised by the deposition of inorganic material, other than metallic material - C23C 16/26: Deposition of carbon only - B05D 2201/04: Laminate - B05D 2202/00: Metallic substrate - B05D 2203/35: Glass - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) ## Abstract The present invention relates to a method of coating fluorocarbon or hydrocarbon on the surface of a workpiece using atmospheric pressure plasma. More particularly, the present invention relates to a method of coating hydrocarbon or fluorocarbon on the surface of a workpiece using plasma generated under atmospheric pressure such that the workpiece can have a hydrophobic or super-hydrophobic surface. The method of coating a surface of a workpiece with fluorocarbon to be hydrophobic or super-hydrophobic according to the present invention comprises the steps of generating first atmospheric pressure glow plasma by supplying a reaction gas into a discharge space formed between a first electrode and a second electrode, the reaction gas containing hydrogen gas, fluorocarbon gas and inert gas, the first and second electrodes being connected to an RF power supply of an atmospheric pressure plasma generator; and approaching the workpiece to the first electrode downstream of a reaction gas flow passing through the discharge space, such that the plasma created in the discharge space is transferred into a space between the first electrode and the workpiece to generate a second atmospheric pressure glow plasma therein, whereby a fluorocarbon coating layer can be formed on the surface of the workpiece. ## Claims ### Claim 1 A method of coating a surface of a workpiece with fluorocarbon, comprising: generating first atmospheric pressure glow plasma by supplying a reaction gas into a discharge space formed between a first electrode and a second electrode, the reaction gas containing hydrocarbon gas, fluorocarbon gas, and inert gas, the first and second electrodes being connected to an RF power supply of an atmospheric pressure plasma generator; and approaching the workpiece to the first electrode at a downstream side of a flow of the reaction gas passing through the discharge space and placing the workpiece outside the discharge space formed between the first and second electrodes, such that the first atmospheric pressure glow plasma generated in the discharge space is transferred into a space, which is between the first electrode and the workpiece and other than the discharge space, to generate a second atmospheric pressure glow plasma therein, whereby a fluorocarbon coating layer is formed on the surface of the workpiece and a contact angle of the coating layer with water is no less than 150 degrees; wherein a volume ratio fluorocarbon/hydrocarbon of the fluorocarbon gas and hydrocarbon gas contained in the reaction gas is within a range of 0.1 to 10. ### Claim 2 (depends on 1) The method as claimed in claim 1, wherein the hydrocarbon gas is selected from the group consisting of C2H2, CH4, C2H4, C2H6, C3H8, and a mixture of at least two thereof. ### Claim 3 (depends on 2) The method as claimed in claim 2, wherein the fluorocarbon gas is selected from the group consisting of CF3, CF4, C2F6, C4F8, and a mixture thereof. ### Claim 4 (depends on 1) The method as claimed in claim 1, wherein a volume of the inert gas contained in the reaction gas is at least 90% of a total volume of the reaction gas. ### Claim 5 (depends on 1) The method as claimed in claim 1, wherein the first electrode has a shape of a rod with a predetermined length, the second electrode is spaced apart from the first electrode by a predetermined distance along a longitudinal direction of the first electrode to thereby form the discharge space, the atmospheric pressure plasma generator further includes a gas supply unit formed with a passage through which the reaction gas is supplied to the discharge space, and the passage includes a buffer space formed along the longitudinal direction of the first electrode, a mixing space formed along the longitudinal direction of the first electrode and having one side opened toward the discharge space, and an orifice formed from the buffer space toward an inner wall of the mixing space to connect the buffer space to the mixing space.