# US 2018/0022936 A1 · Sol-gel coating compositions and related processes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0022936 A1 - Document ID: US20180022936A1 - Status: Published application - Kind: A1 - Application number: 15/231,617 - Filed: 2016-08-08 - Published: 2018-01-25 - Earliest claimed: 2016-07-20 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Vijaykumar S. Ijeri; Om Prakash; Stephen P. Gaydos; Raghavan Subasri; Kalidindi Ramachandra Soma Raju; Dendi Sreenivas Reddy - Web page: https://patentgrep.com/patent/US20180022936A1 ## CPC - C09D 5/086: {Organic or non-macromolecular compounds} - C08G 77/58: Metal-containing linkages - C09D 5/08: Anti-corrosive paints - C09D 183/14: in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms (C09D183/10 takes precedence) - C23C 18/122: {Inorganic polymers, e.g. silanes, polysilazanes, polysiloxanes} - C23C 18/1225: {Deposition of multilayers of inorganic material} - C23C 18/1241: {Metallic substrates} - C23C 18/1254: {Sol or sol-gel processing} - B05D 3/0254: {After-treatment} - B05D 3/067: {Curing or cross-linking the coating} - B05D 7/14: to metal, e.g. car bodies (involving a chemical reaction between the metal and the coating C23) - B05D 7/572: {all layers being cured or baked together} - B05D 7/576: {each layer being cured, at least partially, separately} - B05D 2202/25: based on Al - B05D 2518/12: Ceramic precursors (polysiloxanes, polysilazanes) - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS - 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 An alkoxysilane is contacted with water and an inorganic acid to form a first composition. A zirconium alkoxide is contacted with an organic acid to form a second composition. One or more alkoxysilanes and an organic acid are contacted with a mixture of the first and second compositions to form a sol-gel composition, to which a photoinitiator is added. The sol-gel composition has a ratio of a number of moles of silicon to a number of moles of zirconium (nSi/nZr) ranging from about 2 to about 10. The sol-gel composition is applied on a substrate (e.g., an aluminum alloy substrate) multiple times to form multiple sol-gel layers, and at least one of the sol-gel layers is cured by UV radiation. The multiple sol-gel layers are then thermally cured. ## Claims ### Claim 1 A method comprising: contacting a first alkoxysilane with water and an inorganic acid to form a first composition; contacting a zirconium alkoxide with a first organic acid to form a second composition; contacting the first composition with the second composition to form a mixture; contacting one or more second alkoxysilanes and a second organic acid with the mixture to form a sol-gel composition, the sol-gel composition having a ratio of a number of moles of silicon to a number of moles of zirconium (nSi/nZr) ranging from about 2 to about 10; and adding a photoinitiator to the sol-gel composition. ### Claim 2 (depends on 1) The method of claim 1, further comprising: diluting the sol-gel composition with a solvent and stirring. ### Claim 3 (depends on 1) The method of claim 1, wherein the contacting to form the first composition comprises mixing the first alkoxysilane having the formula RA—Si—(RB)3 with the water and the inorganic acid, wherein the RA is methacryloxyalkyl or glycidyloxyalkyl, and wherein the RB is methoxy or ethoxy. ### Claim 4 (depends on 3) The method of claim 3, wherein the mixing comprises: adding the water to a methacryloxypropyl alkoxysilane, the ratio of a number of moles of silicon to a number of moles of water (nSi/nwater) ranging from about 0.5 to about 2; and adding the inorganic acid and stirring. ### Claim 5 (depends on 1) The method of claim 1, wherein the contacting to form the second composition comprises mixing the zirconium alkoxide having the formula Zr—(RC)4 with methacrylic acid (MAA), and wherein the RC is ethoxy, n-propoxy, isopropoxy, n-butyloxy, or tert-butyloxy. ### Claim 6 (depends on 5) The method of claim 5, wherein the mixing comprises adding MAA to zirconium n-propoxide and stirring, the ratio of a number of moles of zirconium to a number of moles of MAA (nZr/nMAA) ranging from about 0.5 to about 2. ### Claim 7 (depends on 1) The method of claim 1, wherein the contacting to from the sol-gel composition comprises: adding the one or more second alkoxysilanes each having the formula RD—Si—(RE)3 to the mixture, wherein the RD is aryl, aminoalkyl, or glycidoxyalkyl, and wherein the RE is methoxy or ethoxy; and adding MAA and stirring. ### Claim 8 (depends on 7) The method of claim 7, wherein the adding the one or more second alkoxysilanes comprise: adding a phenyl alkoxysilane and stirring; adding an aminopropyl alkoxysilane and stirring; and adding a glycidoxypropyl alkoxysilane. ### Claim 9 (depends on 1) The method of claim 1, wherein the adding the photoinitiator comprises adding the photoinitiator in an amount ranging from about 0.5 to about 3 parts by weight per 100 parts by weight of the sol-gel composition. ### Claim 10 (depends on 1) The sol-gel composition prepared by the method of claim 1. ### Claim 11 (depends on 1) The method of claim 1, further comprising: applying the sol-gel composition on a substrate a plurality of times to form a plurality of sol-gel layers; curing at least one of the plurality of sol-gel layers by UV radiation; and thermally curing the plurality of sol-gel layers to form a corrosion-resistant coating comprising the plurality of sol-gel layers. ### Claim 12 (depends on 11) The method of claim 11, wherein the curing the at least one of the plurality of sol-gel layers by the UV radiation comprises exposing the at least one of the plurality of sol-gel layers to the UV radiation having a light dose ranging from about 500 to about 1000 mJ/cm2 for a time period ranging from about 0.5 to about 30 min. ### Claim 13 (depends on 11) The method of claim 11, wherein the thermally curing the plurality of sol-gel layers comprises curing the plurality of sol-gel layers at a temperature ranging from about 70 to about 90° C. for a time period ranging from about 40 to about 120 minutes in a hot air circulated oven. ### Claim 14 (depends on 11) The method of claim 11, wherein the thermally curing the plurality of sol-gel layers comprises exposing the plurality of sol-gel layers to infrared (IR) radiation, near IR radiation, microwave radiation, or a combination thereof. ### Claim 15 (depends on 11) The method of claim 11, further comprising applying primer and/or paint on the plurality of sol-gel layers on the substrate, the plurality of sol-gel layers facilitating adherence of the primer or the paint to the substrate, wherein the substrate comprises an aluminum alloy substrate selected from the group comprising 2024 aluminum alloy, 6061 aluminum alloy, and 7075 aluminum alloy. ### Claim 16 (depends on 11) The corrosion-resistant coating formed by the method of claim 11. ### Claim 17 (depends on 1) The method of claim 1, further comprising: contacting the sol-gel composition with the substrate to form a first layer of the sol-gel composition on the substrate; exposing the first layer to UV radiation; contacting the sol-gel composition with the first layer to form a second layer of the sol-gel composition on the first layer; exposing the second layer to the UV radiation; and thermally curing the first layer and the second layer to form a corrosion-resistant coating comprising the first layer and the second layer. ### Claim 18 (depends on 17) The method of claim 17, further comprising: contacting the sol-gel composition with the second layer to form a third layer of the sol-gel composition on the second layer; and exposing the third layer to the UV radiation; wherein the corrosion-resistant coating further comprise the third layer. ### Claim 19 A corrosion-resistant coated product, comprising: a plurality of ultraviolet (UV)-cured sol-gel layers on a substrate, each of the UV-cured sol-gel layers comprising a photoinitiator and a polymer composite of one or more alkoxysilanes, a zirconium alkoxide, and an organic acid, and each of the UV-cured sol-gel layers having a ratio of a number of moles of silicon to a number of moles of zirconium (nSi/nZr) ranging from about 2 to about 10. ### Claim 20 (depends on 19) The corrosion-resistant coated product of claim 19, wherein each of the UV-cured sol-gel layers comprise a polymer composite of a methacryloxyalkyl alkoxysilane, an aryl alkoxysilane, an aminoalkyl alkoxysilane, a glycidoxyalkyl alkoxysilane, the zirconium alkoxide, and methacrylic acid (MAA).