Device with liquid-impregnated surface

Abstract

Described herein is a device for conveying fluids and / or solids that has a surface that provides a high slip boundary condition, thereby facilitating material flow.SOLUTION: In some embodiments, the device has a surface with an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced sufficiently close to stably contain the impregnating liquid therebetween. The impregnating liquid fills the space between the solid features, the inner surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially retained in place between the plurality of solid features independent of the orientation of the surface and independent of the flow, passage, or removal of fluid and / or solids through, into, or out of the device.SELECTED DRAWING: None

Description

[Technical Field]

[0001] Related Applications This application claims priority to and the benefit of U.S. Provisional Patent Application No. 61 / 651,543, filed May 24, 2012, U.S. Provisional Patent Application No. 61 / 651,542, filed May 24, 2012, and U.S. Provisional Patent Application No. 61 / 651,541, filed May 24, 2012, which are incorporated herein by reference.

[0002] Technical Field The present invention relates generally to liquid-impregnated surfaces. More particularly, in certain embodiments, the present invention relates to devices and appliances having liquid-impregnated surfaces. [Background technology]

[0003] background Over the past decade, the emergence of micro / nano-engineered surfaces has opened up new techniques for enhancing a wide variety of physical phenomena in thermofluid science. For example, the use of micro / nano surface textures has resulted in non-wetting surfaces capable of achieving low viscous drag, low adhesion to ice and other materials, self-cleaning, and water repellency. These improvements generally result from reduced contact between the solid surface and the adjacent liquid (i.e., reduced wetting). Liquid-impregnated surfaces are described in "Liquid-Impregnated Surfaces, Methods" by Smith et al., the entire text of which is incorporated herein by reference. No. 13 / 302,356, published as U.S. Patent Application Publication No. 2013 / 0032316, entitled "Self-Lubricating Surfaces for Food Packaging and Food Processing Equipment," by Smith et al.; and U.S. Provisional Patent Application No. 61 / 827,444, filed May 24, 2013, entitled "Apparatus and Methods Employing Liquid-Impregnated Surfaces," by Smith et al. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2013 / 0032316 Summary of the Invention [Problem to be solved by the invention]

[0005] There is a need for conduits (e.g., tubes, pipes, channels, vessels, etc.) that have low resistance to the flow, passage, or removal of materials passing through, entering, or exiting the conduit; contact lenses that have high lubricity to ocular tissue and / or ocular fluids for increased comfort, reduced nucleation, and improved resistance to protein buildup and contamination; and devices and instruments that have high lubricity to flesh (or biological fluids) and / or that inhibit nucleation on the surface of the device / instrument. [Means for solving the problem]

[0006] Summary of the Invention In one aspect of the present invention, in some implementations, a conduit for conveying fluids and / or solids is provided that is configured to provide high-slip boundary conditions. A conduit is provided having an interior surface that provides a desired condition, thereby facilitating the flow of material therethrough.

[0007] In one aspect, the present invention provides a conduit for transporting fluids and / or solids, the conduit having an inner surface including an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. In some implementations, the impregnating liquid fills the spaces between the solid features. The inner surface may stably contain the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the plurality of solid features, regardless of the orientation of the inner surface and regardless of the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit. The inner surface may be configured to provide a high-slip boundary condition at the inner surface, thereby facilitating the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit.

[0008] In some implementations, the conduit is a tube, pipe, or channel. In some implementations, the conduit is a nozzle. In some implementations, the conduit is a mold (e.g., part of an injection molding machine) or part of an extruder. In some implementations, the conduit is a canister or vessel.

[0009] In some implementations, the conduit includes a reservoir containing a liquid for replacing impregnating liquid lost from the liquid-impregnated surface. In some implementations, the device includes a conduit and a reservoir containing a liquid for replacing impregnating liquid lost from the liquid-impregnated surface.

[0010] In some implementations, the impregnation liquid is ethyl oleate, esters, fatty acids, fatty acid derivatives, vegetable oils (e.g., olive oil, light olive oil, corn oil, soybean oil, rapeseed oil, linseed oil, grapeseed oil, flaxseed oil, etc.), or the like. oil), canola oil, peanut oil, safflower oil, sunflower oil), phenyl isothiocyanate (phenyl mustard oil), terpenes, bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, methylene iodide (diiodo) methane, stanolax, Squibb's liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, amyl phthalate, silicone oil, perfluorocarbon liquids, perfluorofluorinated vacuum oil oil (such as Krytox 1506 or Fromblin 06 / 6), fluorinated coolants (e.g., perfluoro-tripentylamine sold as FC-70 by 3M), ionic liquids, water-immiscible fluorinated ionic liquids, silicone oils including PDMS, fluorinated silicone oils, liquid metals, electro-rheological fluids, magneto-rheological fluids, ferrofluids, dielectric liquids, hydrocarbon liquids, fluorocarbon liquids, coolants, vacuum oils, phase change materials, semi-liquids, greases, synovial fluids, and body fluids.

[0011] In some implementations, the solid features may be wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, silica, glass, metal, polymers (e.g., polytetrafluoroethylene, fluoroacrylate, fluoroeurathane, fluorosilicone, fluorosilane, modified carbonates), or the like. carbonate), chlorosilanes, silicones, polydimethylsiloxane (PDMS), ceramic solids, fluorinated solids, intermetallic solids, composite solids, PDMS, cyclic olefin polymers, polypropylene, PVC, PET, HDPE, polyimide, PMMA, glass, Perspex, Plexiglass, Polymacon, hydrocarbons (e.g., alkanes), fluoropolymers, Teflon, trichloro(1H,1H,2H,2H-perfluorooctyl)silane (TCS), octadecyltrichlorosilane (OTS) , heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane, fluoroPOSS), ceramics (e.g., titanium carbide, titanium nitride, chromium nitride, boron nitride, chromium carbide, molybdenum carbide, titanium carbonitride, electroless nickel, zirconium nitride, fluorinated silicon dioxide, titanium dioxide, tantalum oxide, tantalum nitride, diamond-like carbon, fluorinated diamond-like carbon), intermetallic compounds (e.g., nickel aluminide and titanium aluminide), and composites.

[0012] In some implementations, the solid features include particles having an average size ranging from 1 micron to 50 microns (e.g., 5 microns to 50 microns). In some implementations, the particles are disposed with an average spacing between adjacent particles or groups of particles of about 1 micron to about 30 microns (e.g., 10 microns to 30 microns). In some implementations, the particles are spray-deposited.

[0013] In some implementations, the solid feature includes or defines at least one element selected from the group consisting of a particle, an amorphous particle, a substantially spherical particle, a post, a nanoneedle, a microneedle, nanograss, micrograss, a pore, a cavity, a well, an interconnected pore, an interconnected cavity, a groove, and a ridge.

[0014] In some implementations, the impregnating liquid includes an additive that prevents or reduces evaporation of the impregnating liquid.

[0015] In another aspect of the invention, in some implementations, two components are configured to contact each other when the device is in operation, and one or each of the two components includes an impregnating liquid and a surface having a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. In some implementations, for each of the surfaces, the impregnating liquid fills the spaces between the solid features, and for each of the surfaces, the surface stably contains the impregnating liquid therebetween. In some implementations, for each of the surfaces, the impregnating liquid is substantially held in place between the plurality of solid features, regardless of the orientation of the surfaces and regardless of contact made between the surfaces (e.g., when the device is configured to induce adhesion normal to the surface; e.g., when the device is configured to have a low static coefficient of friction; or e.g., when the device is configured to induce adhesion normal to the surface and have a low static coefficient of friction). In some implementations, the device is a bearing, a track, or a hinge.

[0016] In another aspect of the invention, in some implementations, the disclosed techniques are used with an apparatus for capturing solid particles from air or other gases. The apparatus includes a surface containing an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. The impregnating liquid fills the spaces between the solid features, and the surface stably contains the impregnating liquid between the solid features. In some implementations, the impregnating liquid is substantially held in place between the plurality of solid features, regardless of the orientation of the surface.

[0017] In some implementations, the device is an air filter.

[0018] The impregnation liquid may have a high viscosity (e.g., greater than 100 cP or greater than 1000 cP).

[0019] In another aspect of the invention, in some implementations, the disclosed techniques are used with a device that includes a surface having a curable impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween, where the impregnating liquid fills the spaces between the solid features, and the surface stably contains the impregnating liquid between the solid features. In some implementations, the impregnating liquid is substantially held in place between the plurality of solid features regardless of the orientation of the surface, and the impregnating liquid can be converted to a solid by curing (e.g., exposure to heat).

[0020] In another aspect of the invention, in some implementations, the disclosed technology is used with an apparatus (e.g., an aircraft, a boat, a torpedo, etc.) that includes a surface configured to reduce drag, the surface including an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. In some implementations, the impregnating liquid fills the spaces between the solid features, and the surface stably contains the impregnating liquid therebetween. In some implementations, the impregnating liquid is substantially held in place between the plurality of solid features, regardless of the orientation of the surface.

[0021] In one aspect of the present invention, in some implementations, medical devices and implements are provided that have liquid-impregnated surfaces to enhance lubricity to flesh (or biofluids) and / or inhibit nucleation on the surface of the device / implement.

[0022] In one aspect, the present invention provides a medical device or medical implement that is highly lubricious to flesh (or biofluids) and / or inhibits nucleation on its surface, the device or implement comprising a surface including an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. In some embodiments, the impregnating liquid fills the spaces between the solid features, and the surface stably contains the impregnating liquid between the solid features. In some embodiments, the impregnating liquid is substantially held in place between the solid features, regardless of the orientation of the surface.

[0023] In some embodiments, the solid features include particles having an average size ranging from 1 micron to 50 microns (e.g., 5 microns to 50 microns). The particles may be disposed with an average spacing of about 1 micron to about 30 microns (e.g., 10 microns to 30 microns) between adjacent particles or groups of particles. The particles may be spray-deposited.

[0024] In some embodiments, the impregnation liquid is selected from the group consisting of ethyl oleate, esters, fatty acids, fatty acid derivatives, vegetable oils (e.g., olive oil, light olive oil, corn oil, soybean oil, rapeseed oil, linseed oil, grapeseed oil, flaxseed oil, canola oil, peanut oil, safflower oil, and sunflower oil), terpenes, phenyl isothiocyanate (phenyl mustard oil), bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, and iodine. The solvent may include at least one member selected from the group consisting of methylene chloride (diiodomethane), stanolax, Squibb's liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, and amyl phthalate.

[0025] In some embodiments, the solid features comprise one or more members selected from the group consisting of wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, metal, polymer, ceramic solid, fluorinated solid, intermetallic solid, composite solid, PDMS, cyclic olefin polymer, polypropylene, PVC, PET, HDPE, polyimide, PMMA, glass, Perspex, Plexiglass, and Polymacon.

[0026] The impregnating liquid may include an additive that prevents or reduces evaporation of the impregnating liquid. The medical device or medical implement may be a member selected from the group consisting of a fixture, a denture, a retainer, an orthodonture, a bridge, an implant, a dental form, a prosthesis, an artificial organ, an artificial artery, a stent, a syringe, an lining (e.g., an lining of an artery wall to prevent plaque formation), IV tubing, an IV bag, a colostomy bag, a surgical instrument, a bandage, and a blood pump.

[0027] The medical device or medical implement may be a blood pump or portion thereof. The surface may be configured to provide reduced shear forces to prevent damage to cells and / or other biological structures in blood or other biological fluids pumped by or through the pump. The medical device or medical implement may be a member selected from the group consisting of a pill, a capsule (e.g., single-piece or two-piece), a tablet, a gelcap, and a suppository.

[0028] The medical device or medical instrument may be a member selected from the group consisting of a micropipette, a small volume container of biological material, a human serum container, a pipette, a pipette tip, a microfluidic device, a dialysis machine, a tubing, an endoscope, an intubation device, a syringe, a stent, a catheter, and a tracheostomy tube.

[0029] Medical devices or instruments include gloves, bandages, adhesive strips, The impregnating liquid may be a member selected from the group consisting of a strip, a drug release patch, and a condom. The impregnating liquid may be antiseptic and / or antibacterial. The impregnating liquid may be hardenable and can be converted to a solid by hardening (e.g., exposure to heat).

[0030] In one aspect of the present invention, in some implementations, contact lenses are provided having a liquid-impregnated surface for increased lubrication to ocular tissues and / or ocular fluids, increased comfort, reduced nucleation, and improved resistance to protein buildup and contamination.

[0031] In one aspect, the present invention provides a contact lens with enhanced lubricity to ocular tissues / fluids and / or inhibited nucleation on its surface, the contact lens comprising a surface textured to form a matrix of microscale and / or nanoscale solid (e.g., gel) features spaced closely enough to stably contain an impregnating liquid between the solid features. The impregnating liquid fills the spaces between the solid features. The surface may stably contain the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the solid features, regardless of the orientation of the surface and despite contact with ocular tissues during normal contact lens donning, insertion, and removal.

[0032] In some implementations, the features define pores or cavities, and the impregnating liquid fills the pores or cavities. The matrix may have feature-to-feature spacing of about 1 micrometer to about 100 micrometers. The matrix has feature-to-feature spacing of about 5 nanometers to about 1 micrometer. The surface is laser etched to form the matrix of solid features. The impregnating liquid is substantially immiscible with ocular fluids (e.g., substantially immiscible with saline solution).

[0033] The material of the solid features and / or the lens itself may include one or more members selected from the group consisting of polymers, hydrogels, polyimides, polymacons, silicone hydrogels, polymethylmethacrylate (PMMA or Perspex / Plexiglas), and glass.

[0034] The solid features may comprise one or more members selected from the group consisting of wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, silica, metal, polymer, ceramic solid, fluorinated solid, intermetallic solid, and composite solid, PDMS, cyclic olefin polymer, polypropylene, PVC, PET, and HDPE.

[0035] The impregnation liquids are ethyl oleate, esters, fatty acids, fatty acid derivatives, terpenes, oils, tetrachloroethylene (perchloroethylene), phenyl isothiocyanate, bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, and carbon disulfide. , bromoform, methylene iodide (diiodomethane), stanolax, liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, and amyl phthalate.

[0036] In some implementations, the impregnating liquid includes a drug for delivery to the surface of the eye.

[0037] In some implementations, the impregnating liquid is colored (e.g., for colored contact lenses).

[0038] In some implementations, the impregnating liquid forms a liquid layer that extends above the top of the solid features of the surface while in equilibrium or substantial equilibrium.

[0039] In some implementations, the liquid layer extends at least about 5 nm above the top of the solid features.

[0040] In some implementations, the impregnating liquid includes a medicinal agent (e.g., a preservative and / or an antimicrobial agent) or a bioactive ingredient (including, but not limited to, drugs, vitamins, minerals, proteins).

[0041] In some implementations, the following are true: (i) 0<φ≦0.25, where φ is a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to the unimmersed solid at equilibrium; and (ii) S ow(a) <0(in the formula, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by the subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid.

[0042] In some implementations, the following conditions are satisfied: (i) 0<φ≦0.25, where φ is a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to the unimmersed solid at equilibrium; and (ii) S ow(a) <0(in the formula, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid. In some implementations, 0 < φ ≦ 0.25. In some implementations, 0 < φ ≦ 0.10. In some implementations, 0.01 < φ ≦ 0.25. In some implementations, 0.01 < φ ≦ 0.10. In some implementations, S ow(a) <0.

[0043] In some implementations, (i) θ os(w),receding =0 and (ii) θ os(a),receding =0 and θ os(w),receding =0, where θ os(w),receding is the receding contact angle of an impregnating liquid (e.g., oil, subscript “o”) on a surface (subscript “s”) in the presence of water (subscript “w”), and θ os(a),receding is the receding contact angle of an impregnating liquid (e.g., oil, subscript "o") on a surface (subscript "s") in the presence of air (subscript "a"), where one or both of the above holds. The objects and features of the present invention can be better understood with reference to the drawings and claims described below. In an embodiment of the present invention, for example, the following items are provided: (Item 1) A conduit for conveying fluids and / or solids, said conduit comprising: an impregnation liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; and an inner surface including the impregnating liquid fills spaces between the solid features; the interior surface stably contains the impregnating liquid between the solid features; the impregnating liquid is substantially maintained in place between the plurality of solid features regardless of the orientation of the interior surface and regardless of the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit; A conduit wherein the interior surface is configured to provide a high-slip boundary condition on the interior surface, thereby facilitating the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit. (Item 2) 2. The conduit according to item 1, which is a tube, pipe, or channel. (Item 3) 2. The conduit of item 1, which is a nozzle. (Item 4) 2. The conduit according to item 1, which is a mold (e.g., part of an injection molding machine) or is part of an extruder. (Item 5) 2. The conduit of item 1, which is a canister or vessel. (Item 6) 6. The conduit of any one of items 1 to 5, comprising a liquid-containing reservoir for replenishing impregnating liquid lost from the liquid-impregnated surface. (Item 7) 6. An apparatus comprising the conduit of any one of items 1 to 5 and a reservoir containing a liquid for replacing impregnating liquid lost from the liquid-impregnated surface. (Item 8) The impregnation liquid may be selected from the group consisting of ethyl oleate, esters, fatty acids, fatty acid derivatives, vegetable oils (e.g., olive oil, light olive oil, corn oil, soybean oil, rapeseed oil, linseed oil, grapeseed oil, flaxseed oil, canola oil, peanut oil, safflower oil, and sunflower oil), phenyl isothiocyanate (phenyl mustard oil), terpenes, bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, and methylene iodide. (Diiodomethane), Stanolax, Squibb's liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, amyl phthalate, silicone oil, perfluorocarbon liquid, perfluorofluorinated vacuum oil (Krytox 1506 or Fromblin 06 / 6), a fluorinated coolant (e.g., perfluoro-tripentylamine sold as FC-70 by 3M), an ionic liquid, a fluorinated ionic liquid immiscible in water, a silicone oil with PDMS, a fluorinated silicone oil, a liquid metal, an electrorheological fluid, a magnetorheological fluid, a ferrofluid, a dielectric liquid, a hydrocarbon liquid, a fluorocarbon liquid, a coolant, a vacuum oil, a phase change material, a semi-liquid, a grease, a synovial fluid, and a body fluid. (Item 9) The solid feature may be selected from the group consisting of wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, silica, glass, metal, polymer (e.g., polytetrafluoroethylene, fluoroacrylate, fluoroeurathane, fluorosilicone, fluorosilane, modified carbonate, chlorosilane, silicone, polydimethylsiloxane (PDMS)), ceramic solids, fluorinated solids, intermetallic solids, composite solids, PDMS, ring 9. The conduit of any one of items 1 to 8, comprising one or more elements selected from the group consisting of: olefin polymers, polypropylene, PVC, PET, HDPE, polyimide, PMMA, glass, Perspex, Plexiglass, Polymacon, hydrocarbons (e.g., alkanes, fluoropolymers, Teflon, trichloro(1H,1H,2H,2H-perfluorooctyl)silane (TCS), octadecyltrichlorosilane (OTS), heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane, fluoro-POSS), ceramics (e.g., titanium carbide, titanium nitride, chromium nitride, boron nitride, chromium carbide, molybdenum carbide, titanium carbonitride, electroless nickel, zirconium nitride, fluorinated silicon dioxide, titanium dioxide, tantalum oxide, tantalum nitride, diamond-like carbon, fluorinated diamond-like carbon), intermetallic compounds (e.g., nickel aluminide and titanium aluminide), and composites. (Item 10) 10. The conduit of any one of items 1 to 9, wherein the solid features comprise particles having an average size in the range of 1 micron to 50 microns (e.g., 5 microns to 50 microns). (Item 11) Item 11. The conduit of item 10, wherein the particles are spaced with an average spacing of about 1 micron to about 30 microns (e.g., 10 microns to 30 microns) between adjacent particles or groups of particles. (Item 12) 12. The conduit according to item 10 or 11, wherein the particles are spray-deposited. (Item 13) 13. The conduit of any one of items 1 to 12, wherein the solid features include or define at least one element selected from the group consisting of particles, amorphous particles, substantially spherical particles, posts, nanoneedles, microneedles, nanoglass, microglass, pores, cavities, wells, interconnected pores, interconnected cavities, grooves, and ridges. (Item 14) 10. The conduit of any one of the preceding claims, wherein the impregnating liquid comprises an additive that prevents or reduces evaporation of the impregnating liquid. (Item 15) 1. A device comprising two parts configured to contact each other when the device is in operation, wherein one or each of the two parts: an impregnation liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; a surface comprising a device wherein, for each of the surfaces, the impregnating liquid fills spaces between the solid features; for each of the surfaces, the surface stably contains the impregnating liquid between the solid features; and, for each of the surfaces, the impregnating liquid is substantially held in place between the solid features regardless of the orientation of the surfaces and regardless of contact made between the surfaces (e.g., when the device is configured to induce adhesion normal to the surfaces; e.g., when the device is configured to have a low static coefficient of friction; or, e.g., when the device is configured to induce adhesion normal to the surfaces and have a low static coefficient of friction). (Item 16) Item 16. The device according to item 15, which is a bearing, a track, or a hinge. (Item 17) 1. An apparatus for capturing solid particles from air or other gas, said apparatus comprising: an impregnation liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; a surface comprising the impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the solid features regardless of orientation of the surface. (Item 18) 18. The device of item 17, which is an air filter. (Item 19) 18. The device of item 17, wherein the impregnating liquid has a high viscosity (e.g., greater than 100 cP or greater than 1000 cP). (Item 20) a curable impregnating liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; 1. A device comprising a surface comprising: the impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, the impregnating liquid is substantially held in place between the solid features regardless of orientation of the surface, and the impregnating liquid can be converted to a solid by hardening (e.g., by exposure to heat). (Item 21) 1. A device (e.g., an aircraft, a boat, a torpedo, etc.) including a surface configured to reduce drag, the surface comprising: an impregnation liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; Including, the impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the solid features regardless of orientation of the surface. (Item 22) below: (i) 0<φ≦0.25, where φ is a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to the unimmersed solid at equilibrium; and (ii) S ow(a) <0(in the formula, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by the subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid. 4. A conduit or device according to any one of the preceding items, to which one or both of the following applies: (Item 23) 23. A conduit or device according to item 22, wherein 0<φ≦0.25. (Item 24) 23. A conduit or device according to item 22, wherein 0<φ≦0.10. (Item 25) 23. A conduit or device according to item 22, wherein 0.01<φ≦0.25. (Item 26) 23. A conduit or device according to item 22, wherein 0.01<φ≦0.10. (Item 27) S ow(a) 23. The conduit or device according to item 22, wherein: (Item 28) below: (i) θ os(w),receding =0 and (ii) θ os(a),receding=0 and θ os(w),receding =0 and 22. A conduit or device according to any one of items 1 to 21, to which one or both of the following applies: In the formula, θ os(w),receding is the receding contact angle of the impregnating liquid (e.g., oil, subscript "o") on the surface (subscript "s") in the presence of water (subscript "w"), and θ os(a),receding is the receding contact angle of said impregnating liquid (e.g., oil, subscript "o") on said surface (subscript "s") in the presence of air (subscript "a"). (Item 29) 1. A medical device or medical implement having high lubricity to meat (or biofluids) and / or inhibiting nucleation on its surface, said device or implement comprising: an impregnation liquid; a plurality of microscale and / or nanoscale solid features spaced sufficiently closely together to stably contain said impregnating liquid therebetween; a surface comprising a medical device or medical implement, wherein the impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the solid features regardless of the orientation of the surface. (Item 30) 30. The medical device or medical implement of item 29, wherein the solid features comprise particles having an average dimension in the range of 1 micron to 50 microns (e.g., 5 microns to 50 microns). (Item 31) 31. The medical device or medical implement of item 29 or 30, wherein the particles are spaced at an average spacing of about 1 micron to about 30 microns (e.g., 10 microns to 30 microns) between adjacent particles or groups of particles. (Item 32) 2. The medical device or medical instrument of any one of the preceding items, wherein the particles are deposited by spraying. (Item 33) The impregnation liquid may be selected from the group consisting of ethyl oleate, esters, fatty acids, fatty acid derivatives, vegetable oils (e.g., olive oil, light olive oil, corn oil, soybean oil, rapeseed oil, linseed oil, grapeseed oil, flaxseed oil, canola oil, peanut oil, safflower oil, and sunflower oil), terpenes, phenyl isothiocyanate (phenyl mustard oil), bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, and methylene iodide (diiodomethane). , Stanolax, Squibb's liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, and amyl phthalate. (Item 34) 2. The medical device or medical implement of any preceding item, wherein the solid features comprise one or more elements selected from the group consisting of wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, metal, polymer, ceramic solid, fluorinated solid, intermetallic solid, and composite solid PDMS, cyclic olefin polymer, polypropylene, PVC, PET, HDPE, polyimide, PMMA, glass, Perspex, Plexiglass, and Polymacon. (Item 35) 10. The medical device or medical implement of any one of the preceding items, wherein the impregnating liquid includes an additive that prevents or reduces evaporation of the impregnating liquid. (Item 36) The medical device or medical implement of any one of the preceding items, which is a member selected from the group consisting of a fixture, a denture, a retainer, an orthodontic brace, a bridge, an implant, a dental form, a prosthesis, an artificial organ, an artificial artery, a stent, a syringe, an inner lining (e.g., an inner lining of an arterial wall to prevent plaque formation), IV tubing, an IV bag, a colostomy bag, a surgical instrument, a bandage, and a blood pump. (Item 37) The medical device or medical instrument of any one of the preceding items, wherein the medical device or medical instrument is a blood pump or part thereof, and the surface is configured to provide reduced shear forces to prevent damage to cells and / or other biological structures in blood or other biological fluids pumped by or through the pump. (Item 38) The medical device or medical implement of any one of the preceding items, which is a member selected from the group consisting of a pill, a capsule (e.g., single-piece or two-piece), a tablet, a gelcap, and a suppository. (Item 39) The medical device or medical instrument of any one of the preceding items, which is a member selected from the group consisting of a micropoipette, a small volume container of biological material, a human serum container, a pipette, a pipette tip, a microfluidic device, a dialysis machine, a tube, an endoscope, an intubation device, a syringe, a stent, a catheter, and a tracheostomy tube. (Item 40) Item 41. The medical device or medical implement of any one of the preceding items, which is a member selected from the group consisting of a glove, a bandage, an adhesive strip, a drug-releasing patch, and a condom. The medical device or medical implement of any one of the preceding items, wherein the impregnating liquid comprises a drug (e.g., a preservative and / or an antibacterial agent) or a bioactive ingredient (including, but not limited to, a drug, a vitamin, a mineral, a protein). (Item 42) 2. The medical device or medical implement of any one of the preceding items, wherein the impregnating liquid is curable and can be converted to a solid by curing (e.g., exposure to heat). (Item 43) below: (i) 0<φ≦0.25, where φ is a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to an unimmersed solid at equilibrium; and (ii) S ow(a) <0(in the formula, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by the subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid. A medical device or medical instrument according to any one of the preceding items, to which one or both of the following applies. (Item 44) Item 44. The medical device or medical instrument according to item 43, wherein 0<φ≦0.25. (Item 45) Item 44. The medical device or medical instrument according to item 43, wherein 0<φ≦0.10. (Item 46) Item 47. The medical device or medical instrument according to Item 43, wherein 0.01<φ≦0.25. Item 48: The medical device or medical instrument according to Item 43, wherein 0.01<φ≦0.10. S ow(a) Item 44. The medical device or medical instrument according to item 43, wherein the β-glucan group is <0. (Item 49) below: (i) θ os(w),receding =0 and (ii) θ os(a),receding =0 and θ os(w),receding =0 and 43. The medical device or medical instrument according to any one of items 29 to 42, wherein one or both of the following applies: In the formula, θ os(w),receding is the receding contact angle of the impregnating liquid (e.g., oil, subscript "o") on the surface (subscript "s") in the presence of water (subscript "w"), and θ os(a),receding is the receding contact angle of the impregnating liquid (e.g., oil, subscript "o") on the surface (subscript "s") in the presence of air (subscript "a"). (Item 50) A contact lens having high lubricity to ocular tissues / fluids and / or inhibiting nucleation on its surface, the contact lens comprises a surface textured to form a matrix of microscale and / or nanoscale solid (e.g., gel) features spaced sufficiently closely together to stably contain an impregnating liquid therebetween; a contact lens, wherein the impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the plurality of solid features regardless of the orientation of the surface and despite contact with ocular tissue during normal donning, insertion, and removal of the contact lens. (Item 51) Item 51. The contact lens of item 50, wherein the features define pores or cavities, and the impregnating liquid fills the pores or cavities. (Item 52) 52. The contact lens of item 50 or 51, wherein the matrix has feature-to-feature spacing of about 1 micrometer to about 100 micrometers. (Item 53) Item 10. The contact lens of any one of the preceding items, wherein the matrix has feature-to-feature spacing of about 5 nanometers to about 1 micrometer. (Item 54) 2. The contact lens of any one of the preceding items, wherein the surface is laser etched to form the matrix of solid features. (Item 55) 2. The contact lens of claim 1, wherein the impregnating liquid is substantially immiscible with ocular fluids (e.g., substantially immiscible with saline). (Item 56) 57. The contact lens of claim 56, wherein the material of the solid features and / or the lens itself comprises one or more members selected from the group consisting of polymers, hydrogels, polyimides, polymacones, silicone hydrogels, polymethylmethacrylate (PMMA or Perspex / Plexiglas), and glass. 10. The contact lens of claim 1, wherein the solid features comprise one or more members selected from the group consisting of wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, purified wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, silica, metal, polymer, ceramic solid, fluorinated solid, intermetallic solid, and composite solid, PDMS, cyclic olefin polymer, polypropylene, PVC, PET, and HDPE. (Item 58) The impregnation liquid may be ethyl oleate, esters, fatty acids, fatty acid derivatives, terpenes, oils, tetrachloroethylene (perchloroethylene), phenyl isothiocyanate, bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, The contact lens of any one of the preceding items contains at least one member selected from the group consisting of methylene iodide (diiodomethane), stanolax, liquid paraffin, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, α-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, and amyl phthalate. (Item 59) 2. The contact lens of claim 1, wherein the impregnating liquid comprises a drug for delivery to the eye. (Item 60) The contact lens of any one of the preceding items, wherein the impregnating liquid is colored (e.g., for colored contact lenses). (Item 61) 10. The contact lens of claim 1, wherein the impregnating liquid forms a liquid layer that extends above the top of the solid features of the surface while in a state of equilibrium or substantial equilibrium. (Item 62) Item 62. The contact lens of item 61, wherein the liquid layer extends at least about 5 nm above the top of the solid features. (Item 63) below: (i) 0<φ≦0.25, where φ is a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to an unimmersed solid at equilibrium; and (ii) S ow(a) <0(in the formula, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by the subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid. The contact lens according to any one of the preceding items, wherein one or both of the following applies: (Item 64) Item 64. The contact lens according to item 63, wherein 0<φ≦0.25. (Item 65) Item 64. The contact lens according to item 63, wherein 0<φ≦0.10. (Item 66) Item 64. The contact lens according to item 63, wherein 0.01<φ≦0.25. (Item 67) Item 64. The contact lens according to item 63, wherein 0.01<φ≦0.10. (Item 68) S ow(a) Item 64. The contact lens according to item 63, wherein β-glucan is 0.05% or less. (Item 69) below: (i) θ os(w),receding =0 and (ii) θ os(a),receding =0 and θ os(w),receding =0 and 63. The contact lens according to any one of items 50 to 62, wherein one or both of the following applies: In the formula, θ os(w),receding is the receding contact angle of the impregnating liquid (e.g., oil, subscript "o") on the surface (subscript "s") in the presence of water (subscript "w"), and θ os(a),receding is the receding contact angle of the impregnating liquid (e.g., oil, subscript "o") on the surface (subscript "s") in the presence of air (subscript "a"). [Brief explanation of the drawings]

[0044] [Figure 1] FIG. 1 shows a schematic cross-sectional view and corresponding top view of a partially submerged liquid-impregnated surface.

[0045] [Figure 2] 2A and 2B demonstrate the effectiveness of coating a liquid-impregnated surface on tweezers for drawing blood.

[0046] [Figure 3] 3A and 3B demonstrate that the liquid-impregnated surface pill slides over animal tissue more easily than the uncoated pill.

[0047] [Figure 4] 4A and 4B demonstrate that animal flesh slides more easily on a liquid-impregnated surface than on an uncoated surface.

[0048] [Figure 5A] 5A to 5D show demolding experiments using concrete and a mold coated with a liquid-impregnated surface. [Figure 5B] 5A to 5D show demolding experiments using concrete and a mold coated with a liquid-impregnated surface. [Figure 5CD]5A to 5D show demolding experiments using concrete and a mold coated with a liquid-impregnated surface.

[0049] [Figure 6] FIG. 6 shows a solid-to-solid adhesion experiment to determine the adhesive strength of liquid-impregnated surfaces.

[0050] [Figure 7A] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. [Figure 7B] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. [Figure 7C] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. [Figure 7D] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. [Figure 7E] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. [Figure 7F] 7A through 7F illustrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item.

[0051] [Figure 8] 8A and 8B show the results of the injection molding experiments.

[0052] [Figure 9AB] 9A to 9D show dust capture experiments on liquid-impregnated surfaces. [Figure 9CD] 9A to 9D show dust capture experiments on liquid-impregnated surfaces.

[0053] [Figure 10A]10A to 10E show a conduit experiment to demonstrate the properties of a liquid-impregnated surface on a surface receiving a viscous material. [Figure 10B] 10A to 10E show a conduit experiment to demonstrate the properties of a liquid-impregnated surface on a surface receiving a viscous material. [Figure 10C] 10A to 10E show a conduit experiment to demonstrate the properties of a liquid-impregnated surface on a surface receiving a viscous material. [Figure 10D] 10A to 10E show a conduit experiment to demonstrate the properties of a liquid-impregnated surface on a surface receiving a viscous material. [Figure 10E] 10A to 10E show a conduit experiment to demonstrate the properties of a liquid-impregnated surface on a surface receiving a viscous material.

[0054] [Figure 11A] 11A to 11D show experiments performed to measure the drag force on the surface of a metal sphere. [Figure 11B] 11A to 11D show experiments performed to measure the drag force on the surface of a metal sphere. [Figure 11C] 11A to 11D show experiments performed to measure the drag force on the surface of a metal sphere. [Figure 11D] 11A to 11D show experiments performed to measure the drag force on the surface of a metal sphere.

[0055] [Figure 12] FIG. 12 shows the wetting behavior of a sphere with a liquid-impregnated surface, a sphere with a textured outer surface, and a sphere with a smooth surface.

[0056] [Figure 13] 13A and 13B show the appearance and clarity of a liquid-impregnated surface coated contact lens versus an uncoated contact lens. DETAILED DESCRIPTION OF THE INVENTION

[0057] Detailed Description The compositions, mixtures, systems, devices, methods, and processes of the invention as claimed are intended to encompass variations and adaptations developed using information gained from the embodiments described herein. Adaptations and / or modifications of the compositions, mixtures, systems, devices, methods, and processes described herein may also be made by one skilled in the art.

[0058] Throughout this description, when articles, devices, apparatus, and systems are described as having, including, or comprising particular components, or when processes and methods are described as having, including, or comprising particular steps, it is further contemplated that there are articles, devices, apparatus, and systems of the present invention that consist essentially of or consist of the recited components, and there are processes and methods of the present invention that consist essentially of or consist of the recited processing steps.

[0059] Similarly, when articles, devices, mixtures, apparatus, and compositions are described as having, including, or comprising specific compounds and / or materials, it is further contemplated that there are articles, devices, mixtures, apparatus, and compositions of the invention that consist essentially of or consist of the recited compounds and / or materials.

[0060] It should be understood that the order of steps or order for performing certain actions is immaterial so long as the invention remains operable. Moreover, two or more steps or actions may be conducted simultaneously.

[0061] The mention herein of any publications, for example in the Background section, is not an admission that those publications serve as prior art to any of the claims presented herein. The Background section is presented for purposes of clarity and is not meant to be a statement of prior art to any claim.

[0062] Described herein is a surface including an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween, the impregnating liquid filling the spaces between the solid features, the interior surface stably containing the impregnating liquid between the solid features, and the impregnating liquid being substantially held in place between the plurality of solid features.

[0063] In some embodiments, the solid features may be part of the surface itself (e.g., the surface may be etched or otherwise textured to create the solid features), or the solid features may be attached to the surface. In some embodiments, the solid features comprise an inherently hydrophobic, oleophobic, and / or metalphobic material or coating. For example, the solid features may be made of hydrocarbons such as alkanes and fluoropolymers such as Teflon, trichloro(1H,1H,2H,2H-perfluorooctyl)silane (TCS), octadecyltrichlorosilane (OTS), heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane, fluoro-POSS, and / or other fluoropolymers. Additional potential materials include ceramics, polymeric materials, fluorinated materials, intermetallic compounds, and composite materials. Polymeric materials may include, for example, polytetrafluoroethylene, fluoroacrylate, fluoroeulatane, fluorosilicone, fluorosilane, modified carbonate, chlorosilane, silicone, polydimethylsiloxane (PDMS), and / or combinations thereof. Ceramics may include, for example, titanium carbide, titanium nitride, chromium nitride, boron nitride, chromium carbide, molybdenum carbide, titanium carbonitride, electroless nickel, zirconium nitride, fluorinated silicon dioxide, titanium dioxide, tantalum oxide, tantalum nitride, diamond-like carbon, fluorinated diamond-like carbon, and / or combinations thereof. Intermetallic compounds may include, for example, nickel aluminide, titanium aluminide, and / or combinations thereof.

[0064] The solid features of the liquid-impregnated surface may form a physical texture or surface roughness. The texture may be random, fractal, or patterned. In some embodiments, the texture is a microscale or nanoscale feature. For example, the texture may have a length scale L (e.g., average pore size or average projection height) of less than about 100 microns, less than about 10 microns, less than about 1 micron, less than about 0.1 micron, or less than about 0.01 micron. In some embodiments, the texture includes posts or other protrusions, such as spherical or hemispherical protrusions. Rounded protrusions are believed to be preferred to avoid sharp solid edges and minimize pinning of liquid edges. The texture may be introduced into the surface using any conventional method, including mechanical and / or chemical methods.

[0065] In some embodiments, the solid features comprise particles. In some embodiments, the particles have an average characteristic dimension, for example, in the range of about 5 microns to about 500 microns, or about 5 microns to about 200 microns, or about 10 microns to about 50 microns. In some embodiments, the characteristic dimension is diameter (e.g., for approximately spherical particles), length (e.g., for approximately rod-shaped particles), thickness, depth, or height. In some embodiments, the particles comprise insoluble fiber, purified wood cellulose, microcrystalline cellulose, oat bran fiber, kaolinite (a clay mineral), Japan wax (obtained from berries), pulp (the spongy part of the plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), and / or ethyl hydroxyethyl cellulose. In some embodiments, the particles comprise wax. In some embodiments, the particles are randomly spaced. In some embodiments, the particles are spaced with an average spacing between adjacent particles or groups of particles of about 1 micron to about 500 microns, or about 5 microns to about 200 microns, or about 10 microns to about 30 microns. In some embodiments, the particles are spray-deposited (e.g., deposited by an aerosol or other spray mechanism).

[0066] In some embodiments, microscale features are used. In some embodiments, the microscale features are particles. The particles can be randomly or uniformly dispersed on the surface. The characteristic spacing between particles can be about 200 μm, about 100 μm, about 90 μm, about 80 μm, about 70 μm, about 60 μm, about 50 μm, about 40 μm, about 30 μm, about 20 μm, about 10 μm, about 5 μm, or 1 μm. In some embodiments, the characteristic spacing between particles is in the range of 100 μm to 1 μm, 50 μm to 20 μm, or 40 μm to 30 μm. In some embodiments, the characteristic spacing between particles is in the range of 100 μm to 80 μm, 80 μm to 50 μm, 50 μm to 30 μm, or 30 μm to 10 μm. In some embodiments, the characteristic spacing between particles is in the range of any two of the above values.

[0067] The particles can have an average size of about 200 μm, about 100 μm, about 90 μm, about 80 μm, about 70 μm, about 60 μm, about 50 μm, about 40 μm, about 30 μm, about 20 μm, about 10 μm, about 5 μm, or 1 μm. In some embodiments, the average size of the particles is in the range of 100 μm to 1 μm, 50 μm to 10 μm, or 30 μm to 20 μm. In some embodiments, the average size of the particles is in the range of 100 μm to 80 μm, 80 μm to 50 μm, 50 μm to 30 μm, or 30 μm to 10 μm. In some embodiments, the average size of the particles is in the range of any two of the above values.

[0068] In some embodiments, the particles are porous. The characteristic pore size (e.g., pore width or length) of the particles can be about 5000 nm, about 3000 nm, about 2000 nm, about 1000 nm, about 500 nm, about 400 nm, about 300 nm, about 200 nm, about 100 nm, about 80 nm, about 50, or about 10 nm. In some embodiments, the characteristic pore size is in the range of 200 nm to 2 μm or 100 nm to 1 μm. In some embodiments, the characteristic pore size is in the range of any two of the above values.

[0069] The impregnating liquid of the liquid-impregnated surface can be oil-based or water-based (i.e., aqueous). The liquid can be selected for a given application based on its properties. In some embodiments, the impregnating liquid is an ionic liquid (e.g., BMI-IM). Other examples of possible impregnating liquids include hexadecane, vacuum pump oil (e.g., FOMBLIN® 06 / 6, KRYTOX® 1506), silicone oil (e.g., 10 cSt or 1000 cSt), fluorocarbons (e.g., perfluoro-tripentylamine, FC-70), shear-thinning fluids, shear-thickening fluids, liquid polymers, dissolved polymers, viscoelastic fluids, and / or liquid fluoro-POSS. In one embodiment, the impregnating liquid is made shear-thick by introducing nanoparticles. Shear-thickening impregnating liquids may be desirable, for example, to prevent impalement and resist impacts from impinging liquids. To minimize evaporation of the impregnating liquid from the surface, it may be desirable to use an impregnating liquid with a low vapor pressure (e.g., less than 0.1 mmHg, less than 0.001 mmHg, less than 0.00001 mmHg, or less than 0.000001 mmHg). In some embodiments, the impregnating liquid has a freezing point of less than -20°C, less than -40°C, or about -60°C. In some embodiments, the impregnating liquid has a surface tension of about 15 mN / m, about 20 mN / m, or about 40 mN / m. In some embodiments, the impregnating liquid has a viscosity of about 10 cSt to about 1000 cSt.

[0070] The impregnating liquid may be introduced to the surface using conventional techniques for applying liquids to solids. In some embodiments, the impregnating liquid is applied using a coating process such as dip coating, blade coating, or roller coating. Alternatively, the impregnating liquid may be introduced and / or replenished by flowing a liquid material across the surface. In preferred embodiments, capillary forces hold the liquid in place after it is applied.

[0071] In some embodiments, a texture may be applied to a substrate to form a surface having solid features. Applying the texture may include: exposing the substrate to a solvent (e.g., solvent-induced crystallization), extruding or blow-molding a mixture of materials, roughening the substrate by mechanical action (e.g., tumbling with an abrasive), spray coating, polymer spinning, depositing particles from solution (e.g., layer-by-layer deposition and / or evaporative removal of liquid from a liquid and particle suspension), extruding or blow-molding a foam or foam-forming material (e.g., polyurethane foam), depositing a polymer from solution, extruding or blow-molding a material that expands upon cooling to leave a wrinkled or textured surface, depositing a layer of material onto a surface under tension or compression, performing solventless induced phase separation of a polymer to achieve a porous structure, performing microcontact printing, performing laser rastering, nucleating a solid texture from a vapor (e.g., desublimation), performing anodizing, milling, machining, knurling, e-beam milling, performing thermal or chemical oxidation, and / or performing chemical vapor deposition. In some embodiments, applying the texture to the substrate includes spraying a mixture of edible particles onto the substrate. In some embodiments, impregnating the feature matrix with a liquid includes: spraying an encapsulating liquid onto the feature matrix, brushing a liquid onto the feature matrix, immersing the feature matrix in a liquid, spinning the feature matrix, condensing a liquid onto the feature matrix, depositing a solution comprising the liquid and one or more volatile liquids, and / or spreading the liquid over a surface with a second immiscible liquid. In some embodiments, the liquid is mixed with a solvent and then sprayed, as the solvent reduces the liquid viscosity, making spraying easier and more uniform. The solvent is then completely dried off from the coating. In some embodiments, the method further includes chemically modifying the substrate before applying the texture to the substrate and / or chemically modifying the solid features of the texture. For example, the method may include chemically modifying the substrate with a material (e.g., a hydrophobic material) that has a contact angle with water of greater than 70 degrees.The modification may be performed, for example, after applying the texture, or may be applied to the particles before they are applied to the substrate. In some embodiments, impregnating the feature matrix includes removing excess liquid from the feature matrix. In some embodiments, removing excess liquid includes: using a second immiscible liquid to carry away the excess liquid, using mechanical action to remove the excess liquid, using a porous material to absorb the excess liquid, and / or using gravity or centrifugal force to drain the excess liquid from the feature matrix.

[0072] Liquid-impregnated surfaces are useful for reducing viscous drag between a solid surface and a flowing liquid. In general, the viscous drag or shear stress experienced by a liquid flowing over a solid surface is proportional to the viscosity and shear rate of the liquid adjacent to that surface. The traditional assumption is that liquid molecules in contact with a solid surface adhere to that surface, the so-called "no-slip" boundary condition. While some slippage can occur between the liquid and the surface, the no-slip boundary condition is a useful assumption for most applications. In some embodiments, liquid-impregnated surfaces are desirable because they induce a large amount of slip at the solid surface. Drag reductions of as much as 40% can be realized due to this slippage.

[0073] In some embodiments, impregnation of the liquid into the texture of the liquid-impregnated surface prevents or reduces nucleation in these regions. The reduction in nucleation is enhanced when the liquid coats the top of the solid features of the liquid-impregnated surface. Furthermore, in some embodiments, the liquid-impregnated surface has a low roll-off angle (i.e., the angle or slope of the surface at which a liquid droplet in contact with the surface begins to roll or slide off the surface). The low roll-off angle associated with the liquid-impregnated surface allows a liquid droplet in contact with the surface to easily roll off the surface before the liquid can accumulate on the surface. In some embodiments, the liquid-impregnated surface is used to impart hydrate phobicity, thereby preventing or minimizing hydrate formation. In some embodiments, the liquid-impregnated surface is used to impart salt phobicity, thereby preventing or minimizing the formation of salt or mineral scale.

[0074] In some embodiments, liquid-impregnated surfaces are used to reduce viscous drag between a solid surface and a flowing liquid. In some embodiments, liquid-impregnated surfaces are used to provide lubrication between the liquid-impregnated surface and a material in contact with the surface (or the surface itself, where one liquid-impregnated surface rubs against another, or portions of the liquid-impregnated surface rub against each other). For example, liquid-impregnated surfaces can provide significant sliding / lubrication benefits when in contact with materials that are non-Newtonian materials, Bingham plastics, thixotropic fluids, and / or shear-thickening substances.

[0075] The liquid-impregnated surface may provide anti-fouling and / or self-cleaning properties. The liquid-impregnated surface may be used to promote condensation of moisture.

[0076] As used herein, the emergence area fraction φ is defined as a representative fraction of the projected surface area of ​​the liquid-impregnated surface corresponding to a non-immersed solid at equilibrium (or pseudo-equilibrium). As used herein, the term "equilibrium" refers to a state where the average thickness of the impregnated coating does not change substantially over time due to gravitational drainage when the substrate is held off-horizontal, and evaporation is negligible (e.g., when the liquid-impregnated liquid is placed in an environment saturated with the vapor of the impregnated liquid). Similarly, as used herein, the term "pseudo-equilibrium" refers to a state that is the same except that evaporation may occur.

[0077] Generally, a "representative fraction" of a surface refers to a portion of the surface that has a sufficient number of solid features on the surface such that the portion is adequately representative of the entire surface. In one embodiment, a "representative fraction" is at least one-tenth of the entire surface.

[0078] In some embodiments, φ is zero (e.g., there is a layer of liquid overlying the top of the solid features, which may be at least 1 nm, at least 5 nm, at least 10 nm, or at least 100 nm thick). In some embodiments, φ is less than 0.30, 0.25, 0.20, 0.15, 0.10, 0.05, 0.01, or 0.005. In some embodiments, φ is greater than 0.001, 0.005, 0.01, 0.05, 0.10, 0.15, or 0.20. In some embodiments, φ is in the range of about 0 to about 0.25. In some embodiments, φ is in the range of about 0 to about 0.01. In some embodiments, φ is in the range of about 0.001 to about 0.25. In some embodiments, φ is in the range of about 0.001 to about 0.10.

[0079] In some embodiments, the liquid-impregnated surface is configured to eliminate or induce cloaking by the impregnating liquid, according to various embodiments described herein.

[0080] As used herein, the expansion factor, S ow(a) is γ wa -γ wo -γ oa where γ is the interfacial tension between two phases designated by the subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid. Interfacial tension can be measured using the pendant drop method as described in Stauffer, CE, "The measurement of surface tension by the pendant drop technique," J. Phys. Chem. 1965, Vol. 69, pp. 1933-1938, the text of which is incorporated herein by reference. Exemplary surfaces and their interfacial tension measurements (at about 25°C) are shown in Appendix D, particularly Table S2.

[0081] Without being bound by any particular theory, S less than 0 ow(a) The impregnated liquid with S is greater than 0 without cloaking and consequently there is no loss of impregnated liquid.ow(a) An impregnating liquid having a cloaking effect can cloak an object (condensed water droplets, bacterial colonies, solid surfaces), which can be used to prevent corrosion, staining, etc. In some embodiments, cloaking is used to prevent vapor-liquid transformation (e.g., water vapor, metal vapor, etc.). In some embodiments, cloaking is used to inhibit liquid-solid formation (e.g., ice, metal, etc.). In some embodiments, cloaking is used to create a reservoir for transporting materials, thus allowing the independent cloaked material to be controlled and managed by external means (e.g., electric or magnetic fields).

[0082] In some embodiments, lubricant cloaking is desirable and used as a means to prevent environmental contamination, such as in a time capsule that preserves the contents of the cloaked material. Cloaking can result in the encapsulation of the material, thereby blocking access to the material from the environment. This can be used to transport materials (such as bioassays) over long distances without contamination by the environment.

[0083] In some embodiments, the amount of cloaking can be controlled by various lubricant properties such as viscosity, surface tension, etc. Additionally or alternatively, we can control the non-wetting properties of the cloaked material to release the material. Thus, a system is contemplated in which a liquid is dispensed into a lubricating medium at one end and upon reaching the other end is exposed to an environment that causes the lubricant to become non-cloaked.

[0084] In some embodiments, the impregnating liquid has an S of less than 0. ow(a)Exemplary impregnation liquids include tetrachloroethylene (perchloroethylene), phenyl isothiocyanate (phenyl mustard oil), bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), tetradecane, cyclohexane, ethylene dibromide, carbon disulfide, bromophore, tetrachloroethylene ... The solvents include, but are not limited to, hexane, hexane diisopropyl ether ...

[0085] Referring to FIG. 1 , a schematic cross-sectional view and corresponding top view of a partially immersed liquid-impregnated surface are shown. The top left drawing of FIG. 1 shows a cross-sectional view of a row of cone-shaped solid features. The protruding surface area of ​​the non-immersed solids 102 is shown as the hatched area in a top-down view, while the remaining unhatched area represents the protruding surface area of ​​the immersed liquid-impregnated surface 100. In addition to the protruding surface area of ​​this row of solid features, other solid features arranged in a semi-random pattern are shown as hatched in a top-down view. Similarly, a cross-sectional view of a row of evenly spaced posts is shown on the right side of FIG. 1 . Another fully patterned row of posts is shown as hatched in a top-down view. As will be demonstrated, in some embodiments, the liquid-impregnated surface comprises randomly and / or non-randomly patterned solid features.

[0086] In some embodiments, the material exhibits the nucleation pattern shown in FIG. 1 on its surface. The surface of the material includes an array of microscale or nanoscale solid features spaced closely enough to contain the impregnating liquid therebetween. The impregnating liquid fills the spaces between the solid features, and the surface stably holds the impregnating liquid in place between the solid features, regardless of the orientation of the surface. In some implementations, the particles have an average size of 5 microns to 50 microns. In some implementations, the particles are arranged with an average spacing of about 10 microns to about 30 microns between adjacent particles or groups of particles.

[0087] In some embodiments, the particles are coated onto the surface of the material by spray coating the impregnating liquid solution onto the surface. Spray coating can deposit a uniform coating of the impregnating liquid on the surface of the material. In some implementations, the impregnating liquid can be spray coated onto the surface of the material in multiple steps. In some implementations where the impregnating solution is comprised of several different solutions, solutions of the various components of the impregnating liquid can be spray coated onto the target surface in different steps.

[0088] The application of liquid-impregnated surfaces can be extended to, for example, conduits for transporting fluids and / or solids. The conduit may have an inner surface containing an impregnating liquid and microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. The impregnating liquid may fill the spaces between the solid features. In some implementations, the inner surface stably contains the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the solid features, regardless of the orientation of the inner surface and regardless of the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit. The inner surface may be configured to provide a high-slip boundary condition at the inner surface, thereby facilitating the flow, passage, or removal of fluids and / or solids through, into, or out of the conduit.

[0089] In some implementations, the conduit includes a reservoir for containing a liquid to replenish impregnating liquid lost from the liquid-impregnated surface. The reservoir may provide a continuous supply of the liquid-impregnated surface solution back to the desired surface. In some implementations, the reservoir is used to replenish impregnating liquid lost from the liquid-impregnated surface.

[0090] In some implementations, the impregnation liquid is ethyl oleate, a fatty acid, a vegetable oil (e.g., olive oil, light olive oil, corn oil, soybean oil, rapeseed oil, linseed oil, grapeseed oil, flaxseed oil, canola oil, peanut oil, safflower oil, sunflower oil), tetrachloroethylene (perchloroethylene), phenyl isothiocyanate (phenyl mustard oil), bromobenzene, iodobenzene, o-bromotoluene, α-chloronaphthalene, α-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, methyl ... The impregnation liquid may contain additives that prevent or reduce evaporation of the impregnation liquid.

[0091] In some implementations, the solid features include wax, carnauba wax, beeswax, candelilla wax, zein (derived from corn), dextrin, cellulose ether, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, insoluble fiber, refined wood cellulose, microcrystalline cellulose, kaolinite (a clay mineral), Japan wax, pulp (e.g., the spongy part of a plant stem), ferric oxide, iron oxide, sodium formate, sodium oleate, sodium palmitate, sodium sulfate, metal, polymer, ceramic solid, fluorinated solid, intermetallic solid, and / or composite solid.

[0092] The solid features may include particles having an average size ranging from 5 microns to 50 microns. The particles may be arranged with an average spacing between adjacent particles or groups of particles of about 10 microns to about 30 microns. The particles may be deposited by spray deposition.

[0093] The solid features may include particles, amorphous particles, substantially spherical particles, posts, nanoneedles, microneedles, nanograss, micrograss, pores, cavities, wells, interconnected pores, and / or interconnected cavities.

[0094] The application of liquid-impregnated surfaces can be extended, for example, to devices configured such that two components contact each other when the device is in operation. Each of the two components may include a surface containing the impregnating liquid and microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. For each surface, the impregnating liquid fills the spaces between the solid features. Each surface can stably contain the impregnating liquid between the solid features. For each surface, the impregnating liquid is substantially held in place between the solid features, regardless of the orientation of the surfaces and regardless of the contact made between the surfaces. In some implementations, the device is a thrust bearing.

[0095] In some implementations, the disclosed technology includes an apparatus for capturing solid particles from air or other gases. The apparatus may include a surface having an impregnating liquid and microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. The impregnating liquid may fill the spaces between the solid features. The surface may stably contain the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the solid features regardless of the orientation of the surface. In some implementations, the apparatus is an air filter. The impregnating liquid has a high viscosity (e.g., greater than 1000 cP).

[0096] The disclosed technology, in some implementations, may include a surface having a hardenable impregnating liquid and microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. The impregnating liquid may fill the spaces between the solid features. The surface may stably contain the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the solid features, regardless of the orientation of the surface. The impregnating liquid may be converted to a solid by curing (e.g., exposure to heat).

[0097] The application of liquid-impregnated surfaces can be extended, for example, to devices (e.g., vehicles, automobiles, aircraft, boats, torpedoes, missiles, etc.) having surfaces configured to reduce drag. The surfaces may include impregnating liquid and microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween. The impregnating liquid may fill the spaces between the solid features. The surfaces may stably contain the impregnating liquid between the solid features. The impregnating liquid may be substantially held in place between the solid features, regardless of the orientation of the surfaces.

[0098] Applications of liquid-impregnated surfaces can extend to, for example, fluid transport and manufacturing equipment, systems, and processes, as described below. In some implementations, the liquid-impregnated surfaces are used to pump, package, move, and / or transport fluids / materials. In some implementations, the liquid-impregnated surfaces may be used to transfer fluids between containers. The liquid-impregnated surfaces may be used to transport viscous materials, such as cement, oil, polymers, chocolate, cat food, dog food, wax, and / or heavy oil in the oil and gas industry.

[0099] In some implementations, a no-slip condition between the conduit and the material being conveyed results in a very steep velocity profile at the edges of the conduit. For some processes, this profile is highly undesirable because high shear can actually degrade the material or product. In some implementations, the disclosed technology provides a high-slip boundary condition so that the material moves as, for example, a slug with a very uniform velocity profile. This is beneficial in applications with very viscous materials and applications with low-viscosity materials flowing in small conduits, such as IV drips.

[0100] In some embodiments, a liquid-impregnated surface coating may be applied to IV drips, the inner lining of IV tubing, and the inner surface of IV bags. It is believed that such a coating allows the contents of the IV bag and / or tubing to slide easily along the IV bag and tubing while minimizing waste of the contents. By increasing the slipperiness of the IV lining, the liquid-impregnated surface coating reduces the attractive forces between the IV tubing and bags and their contents. This allows the contents to be easily dispensed. For example, physicians often are unable to deliver the appropriate flow rate of medication to patients because they are unable to load medication into larger gauge IVs. Creating a liquid-impregnated surface within IV tubing provides physicians with the ability to deliver the appropriate flow rate of medication to patients without using larger gauge IVs.

[0101] Application of the liquid-impregnated surface may be used, for example, in molding. For example, the liquid-impregnated surface may be used in transfer molding. In some implementations, a method for transforming any existing surface into a textured surface is included. In some implementations, the textured surface is filled with an uncured liquid polymer (for example). The filled surface (a mold) may be placed on an existing surface so that the liquid polymer contacts the existing surface. The liquid polymer may then be cured and hardened (this can be achieved by various processes depending on the liquid polymer used). After hardening, the mold can be removed, leaving the textured hardened polymer on the surface. In some implementations, the original textured surface (e.g., a mold) can be filled with a mixture of nano- or micro-scale particles and a liquid (e.g., a slurry). The liquid-impregnated surface may be used as a mold release agent.

[0102] The application of liquid-impregnated surfaces may be used, for example, in bearings. For example, a thrust bearing may consist of two liquid-filled surfaces, each with a different immiscible fluid. When the surfaces are in contact, the interface is liquid-liquid. The resulting friction is very low. Shear-thinning fluids may be used to further reduce friction or to tailor the resistance.

[0103] The application of liquid-impregnated surfaces may be used, for example, with high-friction manufacturing processes, containers, and related equipment. For example, liquid-impregnated surfaces may be used in injection molding. Typically, the high shear forces encountered in injection molding can cause viscous heating within the polymer melt and, in extreme cases, can lead to polymer combustion. The application of a liquid-impregnated surface coating to mold runners and cavities substantially reduces shear forces at the wall, resulting in lower injection pressures. This provides several benefits, including reduced energy requirements for injection, meaning the same part can be molded using smaller, less expensive injection molding machines. In some implementations, the coating can simultaneously function as a mold release agent. In some implementations, the power required for extrusion through a nozzle can be significantly reduced if the nozzle is coated with a liquid-impregnated surface. The liquid-impregnated surface may be used to create lubricated die or extruder parts that will not oxidize. The liquid-impregnated surface may also be used to lubricate dies.

[0104] Liquid-impregnated surfaces may be used in extrusion and / or forging. Both extrusion and forging typically involve the flow of highly viscous materials past the face of a die with a small amount of relative slippage (as opposed to the large amount of relative slippage that occurs in conduits such as pipes). This includes the extrusion and / or forging of plastics, metals, food products such as gum and candy, wire, glue, epoxy, rubber, and / or polymers. Liquid-impregnated surfaces may also be used in cold extrusion and / or cold forging.

[0105] Liquid-impregnated surfaces may be used in vessels containing liquid metals, lubricants, caulking compounds, cement, tile grit, plaster, tar, asphalt, coal slurry, wax, laundry detergent, dishwashing detergent, grease containers, refrigerated containers, butane containers, liquid nitrogen containers, liquid helium containers, gas containers, liquefied gas containers, motor oil containers, petroleum products, brake fluid containers, oil containers, paints, inks, construction materials (e.g., intumescent), or other materials and / or containers. Liquid-impregnated surfaces may be used in self-cleaning glass, photovoltaic cells, and / or solar heat generation. Liquid-impregnated surfaces may be used in connection with desalination (e.g., condensers used in desalination), liquid natural gas condensers, and energy storage (e.g., condensers in power plants, oil pipelines, and fuel lines). Liquid-impregnated surfaces may be used to create de-icing surfaces on cars, aircraft, buses, and other vehicles and / or equipment. The liquid-impregnated surface may be used to reduce solid-to-solid friction by applying a step to create a liquid-impregnated surface on one or both sides.

[0106] Liquid-impregnated surfaces may be used in laboratory materials. For example, liquid-impregnated surfaces may be used on pipettes, beakers, and other materials. Liquid-impregnated surfaces may be used in air filtration. For example, an air filter may use a replacement cartridge that includes a liquid-impregnated surface (e.g., woven channels of a liquid-impregnated surface). The air filter cartridge may be incorporated into a device that moves air from the surrounding environment through the cartridge and filters the air. Dust passing through the air filter will, in some implementations, adhere to the liquid-impregnated surface within the cartridge.

[0107] Liquid-impregnated surfaces for slug trapping, insect trapping, and / or pest trapping. For example, the liquid-impregnated surface may be used to trap insects. The encapsulated surface can generate a large normal force, preventing insects that land on the surface from generating enough force to remove themselves. The encapsulated surface may have a similar effect, becoming extremely "sticky" to small insects. The liquid-impregnated surface may also be used as an insecticide by creating a surface that insects cannot land on.

[0108] The liquid-impregnated surface may be used for adhesive strips. In some implementations, the liquid-impregnated surface has strong capillary adhesion in the normal direction resulting from the surface tension of the impregnating liquid, which pulls downward against a solid object perpendicular to the surface (pulling the surface apart). In some implementations, the textured surface may be encapsulated with a liquid (e.g., epoxy) that can solidify or harden. Thus, the curable liquid-encapsulated surface may be conveniently applied similarly to traditional tape, but with the strength of an epoxy.

[0109] Liquid-impregnated surfaces may also be used to display storage. For example, a user can write / print / draw on a properly textured surface. After coating the surface with oil, the writing is effectively locked in and protected.

[0110] Liquid-impregnated surfaces may be used on windshields of airplanes, trains, or automobiles, or similarly for helmet sunshades and / or eyeglasses (e.g., sunglasses). For example, cleaning a windshield with windshield wipers in the rain requires a significant amount of energy. A liquid-filled windshield can potentially repel raindrops without the need for wipers. Similarly, liquid-impregnated surfaces may be applied to aircraft windshields. The liquid-impregnated surface may be applied to the windshield or sprayed onto the windshield from a reservoir as needed (e.g., during aircraft landing, during a rainstorm, etc.).

[0111] The liquid-impregnated surface may be used on skis, ice skates, sleds, swimwear, boats, or other water and / or sports equipment. The liquid-impregnated surface may be used on the face of a torpedo.

[0112] Liquid impregnated surfaces may be used on agricultural tractors, CO2 condensers, LP condensers, N2 condensers, gas condensing surfaces, and / or inside hydraulic and gas lines.

[0113] Liquid-impregnated surfaces may be used in household appliances, accessories, and items such as pots, cookware, dishes, spatulas, pots, plates, drains, and / or toilet bowls. Liquid-impregnated surfaces may be attached to a portion of a surface to capture liquid. Liquid-impregnated surfaces may be used in toys and games. For example, liquid-impregnated surfaces may be used in a slip n slide.

[0114] In some embodiments, the liquid-impregnated surface is created by applying a uniform layer of the impregnating liquid to any surface. This surface may be the surface of a contact lens. The liquid-encapsulated surface can be applied to the contact lens to improve wearer comfort. The liquid-encapsulated surface can also help the contact lens stay hydrated and maintain a tear film in the eye to prevent dry eye symptoms, including burning, stinging, redness, foreign body sensation, excessive tearing, and intermittent blurred vision, and to reduce potential scratching of the eye.

[0115] Currently, the average lifespan of a disposable contact lens is two weeks. Liquid-encapsulated surfaces can substantially extend the lifespan of current disposable contact lenses. A maintained liquid interface between the contact lens and the eye can help reduce wear and tear on the contact lens, thereby improving the lifespan of the contact lens. Liquid-encapsulated surfaces are believed to allow contact lenses to be worn overnight and for periods longer than two weeks.

[0116] In some embodiments, liquid-encapsulated surfaces can also reduce contact lens maintenance. Current rewetting droplet products, such as "Refresh Contacts," "Clerz Plus," or "Clear Eyes Contact Lens Relief," moisten contact lenses and remove particles that build up on the contact lens, causing irritation and discomfort. However, these rewetting droplets are often not required with contact lenses that have a liquid-encapsulated surface, because the liquid-encapsulated surface retains moisture and prevents dry eye. Current contact lenses require nightly soaks in saline to moisten the contact lens. Such nightly soaks may not be necessary with the liquid-encapsulated surface present in improved contact lenses.

[0117] In some embodiments, contact lenses may have texture or roughness on one or both sides of the lens, or may have porosity extending throughout the lens. The liquid contained in the liquid layer of the lens may be applied to one or both sides of the lens. Alternatively, the liquid may be soaked throughout the lens. The liquid may be applied by the user after purchase and reapplied multiple times.

[0118] In some embodiments, the contact lens is composed of a polyimide. Texture can be controlled or tailored through temperature or solvent-induced crystallization of the polymer surface of the polyimide to form spherulites or other fine microstructures. Many polymers already used in contact lens manufacturing undergo spherulite crystallization.

[0119] The solid and liquid materials may be selected from materials already considered safe for contact with the eye by the U.S. Food and Drug Administration. The liquid may be immiscible with ocular fluid, and the ocular fluid may act as a feedstock for the texture.

[0120] In some embodiments, the material of the solid features and the lens itself may be a polymer, hydrogel, polyimide, polymacon, silicone hydrogel, polymethylmethacrylate (PMMA or Perspex / Plexiglas), or any combination of these materials.

[0121] In some embodiments, optical clarity can be achieved by having features smaller than 100 nm or by matching the refractive index of the texture material to the liquid. The liquid and texture would ideally be transparent or translucent, but thin enough to have an effective transmission of at least 95% in the visible spectrum.

[0122] In some embodiments, the impregnating liquid in the liquid layer is colored. The colored impregnation provides the color to the colored contact lens.

[0123] In some embodiments, the impregnating liquid, while at equilibrium or substantially equilibrium, forms a liquid layer that extends above the tops of the solid features of the surface, hi some embodiments, the liquid layer extends at least about 5 nm above the tops of the solid features.

[0124] In some embodiments, current laser etching techniques, such as CO or deep UV, can be adapted to generate a patterned, textured surface across the entire inner surface of a contact lens. Current laser etching techniques only produce small identification marks on the inside of a contact lens. Laser techniques may be extended to produce patterned textures with uniform dimensions across the entire contact lens. It is believed that impregnating this textured surface with a liquid having the same or nearly the same refractive index as the contact lens material will make the contact lens transparent. The exemplary experiment discussed below compares the transparency of a contact lens with a liquid-filled surface to that of a conventional, uncoated contact lens.

[0125] In some embodiments, particles are coated on a surface of a medical device or medical implement by spray coating the surface with an impregnating liquid solution. The spray coating may deposit a uniform coating of the impregnating liquid on the surface of the medical device or medical implement. In some implementations, the impregnating liquid may be spray coated onto the surface of the medical device in multiple steps. In some implementations where the impregnating solution is composed of several different solutions, solutions of various components of the impregnating liquid may be spray coated onto the target surface in different steps.

[0126] Applications of liquid-impregnated surfaces to inhibit nucleation may include, for example, preventing plaque nucleation on teeth, dentures, braces, or retainers. Applications of liquid-impregnated surfaces may include, for example, preventing fibrosis on artificial implants. Further applications may include preventing thrombosis on blood-contacting surfaces or on the surfaces of tubing or artificial arteries or stents, where clogging occurs from the accumulation of cholesterol or other solid-like material. These surfaces would benefit from a more lubricated interface.

[0127] In some embodiments, the liquid-impregnated surface is created by applying a uniform layer of impregnating liquid to a surface, which in some implementations may be human or animal tissue. The uniform layer of impregnating liquid may be sprayed onto the surface to create a uniform liquid-impregnated surface coating.

[0128] In some embodiments, the liquid-impregnated surface coating may be applied to the interior surface of a syringe to facilitate emptying of the syringe contents. For example, the interior surface of the syringe's cylindrical barrel may be coated with the impregnating liquid. This reduces the attractive force between the syringe contents and the interior surface of the syringe's cylindrical barrel, allowing a maximum amount of syringe contents to be expelled with less applied plunger force.

[0129] In some embodiments, a liquid-impregnated surface coating may be applied to an artificial or natural lining of an arterial wall to prevent plaque formation. The lining may be coated with the impregnating liquid in a manner that does not allow plaque to easily adhere to the lining of the arterial wall. The impregnating liquid may be applied to the lining of the arterial wall by pumping the impregnating liquid solution through the arterial wall or by any surgical means.

[0130] In some embodiments, a liquid-impregnated surface coating may be applied to IV drips, the inner lining of IV tubing, and the interior surface of IV bags. Such a coating may allow the contents of the IV bag and / or tubing to slide easily along the IV bag and tubing while minimizing waste of the contents. By increasing the slipperiness of the IV lining, the liquid-impregnated surface coating reduces the attractive forces between the IV tubing and bags and their contents, allowing for easier dispensing of the contents. For example, physicians frequently are unable to deliver adequate medication flow rates to patients because they are unable to load larger gauge IVs. Creating a liquid-impregnated surface within IV tubing provides physicians with the ability to deliver adequate medication flow rates to patients without using larger gauge IVs.

[0131] In some embodiments, a liquid-impregnated surface coating may be applied to the colostomy bag, which may facilitate easier acceptance of bowel movements after colostomy creation and reduce discomfort to the patient.

[0132] In some embodiments, a liquid-impregnated surface coating may be applied to teeth to prevent plaque buildup. By applying such a coating, food particles and other plaque are less likely to adhere to the teeth, thereby increasing the dental health of the subject.

[0133] In some embodiments, liquid-impregnated surface coatings may be applied to metal or metallic surgical instruments, as shown by the experiments illustrated in Figures 2A and 2B discussed below. The application of such coatings to surgical instruments allows bodily fluids, such as blood, to be repelled from the coated surgical instruments, keeping them clean.

[0134] In some embodiments, a liquid-impregnated surface coating may be applied to a bandage to allow for easy removal of the bandage from the skin without causing discomfort to the patient, for example, a bandage having such a liquid-impregnated surface coating does not stick very tightly to the wound or skin over time and pressure and can be easily removed.

[0135] In some embodiments, a liquid-impregnated surface coating may be applied to a blood pump. The shear forces encountered in pumped blood and other biological fluids often damage or destroy cells by detaching them. The liquid-impregnated surface coating significantly reduced the shear forces at the surface of the pump, preventing damage to cells and other biological structures.

[0136] In some embodiments, liquid-impregnated surface coatings may be applied to laboratory supplies and pharmaceuticals to keep them clean and free of foreign matter.

[0137] In some embodiments, liquid-impregnated surface coatings may be applied to pills and capsules to facilitate swallowing, as demonstrated by the experiments illustrated in Figures 3A and 3B discussed below. The application of such coatings to pills reduces friction between the pill and human tissue, allowing the coated pill to slide more easily along the tongue and esophageal tissue.

[0138] In some embodiments, liquid-impregnated surface coatings may be applied to micropipettes, pipettes, pipette tips, and small-volume containers for biological fluids and samples. For small-volume containers and micropipettes, the percentage of the contents that remain attached to the container represents a significant fraction of the total volume of the container. Furthermore, the contents are often expensive and labor-intensive to obtain. Application of an impregnated liquid coating to the interior surfaces of these containers and pipette tips facilitates the removal of the contents from these containers with minimal waste. Similarly, the coating may also adhere to the contents of these containers, particularly DNA and RNA strands, to facilitate the easy removal of these compounds from the small-volume containers.

[0139] In some embodiments, a liquid-impregnated surface coating may be applied to a microfluidic device. Often, microfluidic channels become clogged with contents passing through these channels. By coating the microfluidic channels with a liquid-impregnated surface coating, the contents of these microfluidic channels do not clog the channels, and the microfluidic device can continue to operate for extended periods of time without any maintenance.

[0140] In some embodiments, liquid-impregnated surface coatings can be applied to dialysis tubing and other components of dialysis machines to more easily facilitate the removal of waste and excess water from the blood.

[0141] In some embodiments, the liquid-impregnated surface coating may be applied to any surgical tool inserted into the body, such as endoscopes, stents, syringe needles, catheters, tracheostomy tubes, and intubation devices. When applied to these surfaces, such coatings allow for easier insertion into the body without causing any unwanted lacerations to body tissue. Such coatings allow for more comfortable insertion of intubation equipment. The encapsulated liquid within the coating may contain neutral antiseptics and anesthetics that can anesthetize and cleanse the local area of ​​insertion while the surgical tool is being inserted. An experiment performed using a polypropylene sheet used to simulate the surface of a surgical tool in contact with a steak used to simulate human tissue is shown in Figures 4A and 4B, discussed below.

[0142] In some embodiments, the liquid-impregnated surface coating may be applied to creams, prescription creams, ointments, neosporin, triple antibiotic ointments, burn relieving creams, anti-itch creams, aloe gels, sunscreen lotions, and other lotions. The coating may also be applied to containers of ointments, lotions, and creams. Such coatings may facilitate the release of these chemicals and may prevent the last few drops of such creams, ointments, or lotions from sticking to the walls of the container.

[0143] In some embodiments, the liquid-impregnated surface coating may be applied to medical supplies, gloves, bandages for covering open wounds, dressings for skin conditions, medical implants, and implant coatings to keep them clean from foreign matter.

[0144] In some embodiments, liquid-impregnated surface coatings may be applied to the surfaces of medical devices, artificial hearts, and artificial organs to prevent the buildup of organic materials on these devices.

[0145] In some embodiments, a liquid-impregnated surface coating may be applied to the prosthesis and self-lubricating joint to keep it free of dirt and organic matter buildup that can impair effective movement.

[0146] In some embodiments, the liquid-impregnated surface coating may be applied to orthodontic appliances such as retainers, dental forms, dentures, dental fixtures, invisible braces, etc. The surface coating can prevent plaque buildup on the surfaces of these orthodontic appliances, improving dental health and hygiene.

[0147] In some embodiments, a liquid-impregnated surface coating may be applied to the bridges and wetted surfaces to avoid biofouling.

[0148] In some embodiments, the encapsulated liquid within the liquid-impregnated surface coating may be antiseptic and antibacterial to keep the surface clean, which is especially important in medical applications where cleanliness of the medical device is paramount.

[0149] In some embodiments, a liquid-impregnated surface coating may be applied to the adhesive strip. The liquid-impregnated surface has strong capillary adhesion in the normal direction. Lateral forces depend on the viscosity of the impregnating liquid. An extremely high viscosity impregnating liquid can essentially behave as a solid, preventing slippage and thus the surface may behave similarly to tape. A low viscosity fluid will slide easily, thus resulting in a surface that behaves as an adhesive in the normal direction but slides laterally. Alternatively, the textured surface can be encapsulated with a liquid (i.e., like an epoxy) that can solidify or harden. Thus, a curable liquid-encapsulated surface can adhere as conveniently as a traditional tape, but with the strength of an epoxy.

[0150] In some embodiments, a liquid-impregnated surface coating may be applied to a condom. The protective coating can reduce friction during sexual intercourse and prevent tears. Surface coatings can also be applied to similar adult devices inserted into body orifices to reduce friction and minimize tears.

[0151] In some embodiments, a liquid-impregnated surface coating may be applied to a drug-releasing patch. This product may look similar to a Band-Aid, but the white part of the Band-Aid may be replaced with a liquid-encapsulated surface. The encapsulated liquid may be a drug or medication. This liquid may then be applied to the skin to deliver the medication.

[0152] In some embodiments, liquid-impregnated surface coatings may be applied to cosmetics such as nail polish, shampoo, conditioner, body wash, hair gel, face masks, and toothpaste, etc. Applying such coatings to these cosmetics can make them dust-repellent, preventing dust that may otherwise be attracted to cosmetics applied to the body.

[0153] The mechanical interaction between the surface of a medical device or instrument and tissue or fluid in contact with said surface can be controlled. The fluid may be biological in origin (including, but not limited to, blood, saliva, sweat, urine, or interstitial fluid) or may be an artificial suspension or solution in which bioactive components (including, but not limited to, drugs, vitamins, minerals, proteins, peptides, or nucleic acids) have been added to the fluid.

[0154] In one embodiment, the lubricity of a surface of a medical device or medical implement is modified so that it is more or less lubricious to the tissue or fluid it contacts than an unmodified surface. In this way, the effective coefficient of friction of the surface against the tissue or fluid can be increased or decreased in a controllable manner. For example, if it is desired that the surface of the device or implement move easily across the surface of the tissue or fluid, its effective coefficient of friction can be reduced; similarly, if it is desired that the surface of the device or implement not move easily across the surface of the tissue or fluid (e.g., so that the device or implement is effectively adhered to the tissue or fluid), its effective coefficient of friction can be increased.

[0155] In one embodiment, a medical device or medical implement is provided with controlled lubrication to tissue, or biological fluids, or fluids having suspended or dissolved bioactive components, including drugs, comprising a surface containing an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced closely enough to stably contain the impregnating liquid therebetween, wherein the impregnating liquid fills the spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the solid features regardless of the orientation of the surface.

[0156] In another embodiment of the invention, the lubricity of a device or instrument varies in spatial dimensions for the purpose of spatially controlling the movement of tissue or fluid across the surface of the device or instrument. In one example, it may be desired for fluid to flow easily across some portions of the surface of the device or instrument while being substantially stationary or trapped on other portions of the surface of the device or instrument. In another example, it may be desired to control the interaction between the surface of the device or instrument and tissue so that tissue moves freely over some areas of the surface while remaining substantially attached to other areas of the surface.

[0157] In one embodiment, the properties of the surface and / or the impregnating liquid are varied in spatial dimensions to achieve different lubricity patterns.

[0158] In another embodiment of the present invention, the surface of the tissue itself is modified to control the lubricity between the tissue and the surface of a medical device or instrument, or to counteract the movement of fluids on the tissue surface. The tissue surface can be modified using mechanical, chemical, electrical, or other forces to introduce a plurality of microscale and / or nanoscale solid features into the tissue surface. These features are sufficient to effectively and stably retain an impregnating liquid, and their properties are sufficient to control the lubricity between the thus-modified tissue and the surface of a medical device or instrument, or to counteract the movement of fluids on the tissue surface. This modification of the tissue surface can result in temporary or permanent changes in the lubrication properties of the tissue relative to the surface of the device or instrument, or relative to the fluid.

[0159] In one embodiment, a tissue is provided with controlled lubrication to a medical device or medical implement, or a biological fluid, or a fluid having suspended or dissolved therein a biologically active component, including a drug, the tissue comprising a surface containing an impregnating liquid and a plurality of microscale and / or nanoscale solid features spaced sufficiently closely to stably contain the impregnating liquid therebetween, the impregnating liquid filling the spaces between the solid features, the surface stably containing the impregnating liquid between the solid features, and the impregnating liquid being substantially held in place between the solid features regardless of the orientation of the surface.

[0160] In one embodiment, the properties of the surface and / or the impregnating liquid are varied in spatial dimensions to provide different lubricity patterns. [Example]

[0161] (Experimental Example) Example 1

[0162] Figure 2 shows experimental measurements of the repulsion of a blood droplet from tweezers coated with a liquid-impregnated surface coating. As shown in Figure 2A, two identical plastic tweezers, tweezers 202 and 204, are immersed in a container 206 filled with two drums of porcine blood. Tweezers 202 are uncoated as control tweezers. Tweezers 204 are coated with the liquid-impregnated surface coating. Tweezers 202 and 204 are simultaneously immersed in and removed from container 206. Tweezers 202 and 204 are held in the same hand.

[0163] 2B shows the effect of the surface coating on the tweezers 204 when both tweezers 202 and 204 are removed from a container 206 of porcine blood. The uncoated tweezers 202 are stained with blood residue. The liquid-impregnated surface-coated tweezers 204 have minimal residue, with most of the blood removed when the tweezers 204 are first removed from the container 204.

[0164] The experiment in Figure 2 demonstrates that liquid-impregnated surfaces can be engineered to keep medical devices clean from bodily fluids, which is useful for keeping medical equipment and surgical tools sterile.

[0165] Example 2

[0166] This example demonstrates that a liquid-impregnated pill is easier to swallow than an uncoated pill, as demonstrated by comparing the sliding speed of a liquid-impregnated coated pill across a piece of steak to the sliding speed of an uncoated pill.

[0167] Figure 3A shows screenshots of a video taken to demonstrate the sliding of coated pill 302 and uncoated pill 304 on steaks mimicking esophageal and tongue tissue. The coated and uncoated pills were placed in a parallel orientation on two steaks, steaks 306 and 308, as shown in Figure 3A. Steaks 306 and 308 were positioned at a 65° angle. Pill 302 was coated with a liquid-impregnated surface (carnauba wax and ethyl oleate), while pill 304 was uncoated as a control.

[0168] Specifically, tweezers were used to pick up a cylindrical, pale yellow pill (Vitacost Alpha Lipoic Acid & Acetyl L-Carnitine HCl—1600 mg / dose). Carnauba wax was sprayed onto pill 302 for three seconds to deposit a uniform coating of the liquid-impregnated coating. Nitrogen gas was sprayed over pill 302 for a period of time to allow the coating to dry before depositing the ethyl oleate. Pill 302 was then sprayed with ethyl oleate for three seconds to deposit a uniform coating. Uncoated pill 304 was then placed on steak 308. Pill 302, with its liquid-impregnated surface coated, was placed on steak 306. Pills 302 and 304 were placed on top of their respective steaks. The pills were oriented perpendicular to ruler 310. Stakes 306 and 308 were then adjusted so that their faces were tilted at a 65-degree angle. FIG. 3A shows pills 302 and 304 at zero seconds after the pills are placed on top of the steak.

[0169] Figure 3B shows a screenshot 3.5 seconds after pills 302 and 304 were placed on top of the steaks. At this point, coated pill 302 reached the bottom of steak 306, while uncoated pill 304 remained on top of steak 308. Pill 302 began to slide slowly but quickly accelerated to a speed of approximately 4.5 cm / sec (calculated based on a 7 cm travel distance over 1.5 seconds). The uncoated pill remained on top of the steaks throughout the experiment.

[0170] The experiment in Figure 3 demonstrates that the liquid-impregnated surface coating on the pill surface aids in the pill's sliding on top of animal tissue such as steak, mimicking the surface structure of the human tongue and esophagus, as the uncoated pill did not travel any distance on the steak at the same tilt angle.

[0171] Example 3

[0172] This example demonstrates low friction between a liquid-impregnated surface and meat by comparing the sliding speed of a raw eye-round steak on a liquid-impregnated surface with the sliding speed of another raw eye-round steak on an uncoated surface. Video was taken to demonstrate the movement of the steak on both the uncoated and coated polypropylene sheets.

[0173] This experiment was conducted by first cutting a 12" x 12" polypropylene (PP) sheet (gauge = 0.060") into two 6" x 12" sheets, sheets 406 and 408. Carnauba wax was sprayed onto sheet 408 for 15 to 30 seconds to deposit a uniform coating. Subsequently, ethylene oleate was sprayed onto sheet 408 for 30 to 45 seconds to deposit a uniform coating. Sheet 406 was left uncoated as a control. Sheet 406 was placed next to sheet 408, and both sheets 406 and 408 were positioned at a 45 degree angle. Steak 402 was placed on top of sheet 406. , steak 404 was placed on top of sheet 408. The starting point of the meat steak was 4 inches from the top of the PP sheet. A video of the meat movement was taken to demonstrate the differences between the uncoated and coated PP sheets. FIG. 4A shows a video frame at time zero when the steak was placed on top of the PP sheet. FIG. 4B shows a video frame 131 seconds after the frame shown in FIG. 4B. FIG. 4B shows that steak 404 has reached the bottom of sheet 408, while uncoated steak 402 remains near the top of PP sheet 406.

[0174] The time it took for the steak to travel 8 inches to the bottom of the PP sheet was measured. The steak 404 on the PP sheet 408 took 131 seconds to travel to the bottom of the sheet. The average speed of the liquid-impregnated coated steak 404 on the sheet 408 was 0.055 inches / second. The uncoated steak 402 on the PP sheet 406 moved slightly but remained about 7 inches from the bottom of the sheet after 2 minutes and 30 seconds. After an additional time (about 5 minutes), the steak did not appear to move any further down the inclined ramp.

[0175] The experiment in Figure 4 demonstrates that a liquid-impregnated surface coating on a surface helps animal meat slide across the surface more easily than on an uncoated surface, providing evidence that such liquid-impregnated surface coatings reduce shear forces to prevent damage to cells and other biological structures in the pumped blood or other biological fluid.

[0176] Example 4

[0177] Figures 5A-D show a demolding experiment using concrete and a mold coated with a liquid-impregnated surface. In some embodiments, the liquid-impregnated surface coating may be applied to orthodontic appliances, such as dental forms. A monkey-shaped, ultra-dense plastic bottle with gaps and structures, as shown in Figure 5A, was used to demonstrate the liquid-impregnated surface as a demolding / non-stick coating. An approximately 500 ml HDPE, monkey-shaped bottle was cut in half with a reciprocating saw to produce the front and back halves shown in Figure 5B. The back half of the bottle was coated with the liquid-impregnated surface as described below, while the front half was left uncoated.

[0178] The liquid impregnation solution was sprayed onto the rear half of the bottle. The liquid impregnation solution was prepared by adding 1.5 g of fluorinated wax (HF diblock grey, Toko) to 80 ml of toluene and heating on a hot plate until all the wax was dissolved. The solution was then sonicated for 5 minutes and allowed to cool to room temperature. Finally, 10 g of PTFE particles (1 μm size, Sigma) were added and sonicated for another 5 minutes. The solution was sprayed onto the mold to produce a coating approximately 10 μm thick, and then Galden HT 200 was sprayed to impregnate and fill the texture.

[0179] Fast-setting concrete was mixed according to the manufacturer's instructions and poured into each mold until filled, as shown in Figure 5C. The concrete was allowed to harden at room temperature (70°F) for approximately 15 minutes, and each mold was rolled up and down on a counter. We then easily and completely removed the coated plastic mold from the hardened concrete, leaving behind a casting of the inside of the bottle, as shown in Figure 5D. The uncoated side was not removed from the mold.

[0180] Example 5

[0181] Figure 6 shows a solid-to-solid adhesion experiment. The lateral force (slip) depends on the impregnating liquid viscosity. An impregnating liquid with extremely high viscosity can essentially behave as a solid, preventing slippage; thus, the surface can be thought of as behaving similarly to tape (Figure 6). A low viscosity fluid will slide easily, thus resulting in a surface that behaves like an adhesive in the normal direction but slides laterally (think of an air hockey table, where you can easily slide a mallet down it, but it is extremely difficult to pull it up).

[0182] Adhesion force was obtained by measuring the force required to separate the liquid-impregnated surface from the glass slide in the normal direction. The glass slide was attached to a scale, and the liquid-impregnated surface was pulled up normal to the scale. The capillary force due to the impregnated liquid was calculated as τ adh This resulted in an adhesive strength of 1.1 ± 0.1 Pa. The liquid-impregnated surface was prepared using a lithographically patterned array of 10 um wide and 10 um tall square posts spaced 25 um apart. 10 cSt silicone oil was impregnated onto the surface.

[0183] We have calculated the coefficient of static friction μ between two solid materials with three different configurations. sThe coefficient of friction for each of these configurations was measured. The first interface was silicon on PET (Configuration 1), the second interface was silicon with a liquid-impregnated surface on PET (for which conventional adhesion was measured), and the third interface (Configuration 3) was glass sprayed with carnauba wax to create a textured surface impregnated with ethyl oleate. The underlying PET surface was coated with a thin film of toothpaste, providing preferential contact chemistry for the ethyl oleate over the carnauba wax, ensuring a stable liquid film between the solid materials. The coefficient of friction for each of these configurations was measured as μ s =tan α slide (In the formula, α slide is the angle at which the surface first begins to slide.) As a result of attaching a weight to the top of each surface, the force per unit area of ​​the top surface of each surface was approximately 520±10N / m 2 The start angle α for configurations 1, 2, and 3 was slide are 24°, 16°, and 7°, respectively, resulting in a friction coefficient μ s =tan α slide were 0.44, 0.29, and 0.12, respectively. Thus, both Configurations 2 and 3 yielded lower coefficients of friction than a direct solid / solid interface (Configuration 1). Configuration 3, in which the bottom chemistry was modified by a layer of toothpaste, had the lowest friction—presumably because a thin film of liquid (ethyl oleate) was stable between the toothpaste and carnauba wax, and therefore there was no solid-to-solid contact.

[0184] Example 6

[0185] Figures 7A-F demonstrate the effect of a liquid-impregnated surface on a tube, pipe, channel, or other similar item. PVC pipe was cut into 1-foot sections. A carnauba wax coating (carnauba wax suspended in trichloroethylene, 5% by weight) was sprayed onto both ends of the pipe for 5-20 seconds to deposit a uniform coating on the inside of the pipe. N2 was blown through the pipe from end to end and into the interior, allowing the coating to dry (approximately 1-2 minutes). Ethyl oleate was then sprayed onto both ends of the pipe for 5-20 seconds until the pipe was clear again (indicating complete impregnation of the texture). The resulting product was a pipe with a liquid-impregnated interior surface.

[0186] Equal lengths of liquid-impregnated and unmodified pipes were assembled in a pipe tester. The unmodified pipe served as a control to evaluate the impact of the liquid-impregnated pipe. Figure 7A shows two pipes secured to cardboard using tape. Labels reading "Start" and "Finish" were attached to the same location on both pipes. The labels were separated by 20 cm on each pipe. 20 grams of toothpaste was applied to the start line on both tubes. The pipe tester was positioned at a 45-degree angle, and the toothpaste velocity and the time it took for the toothpaste to travel 20 cm from the start line to the finish line were measured. Figures 7B-E show the position of the toothpaste over time on the uncoated and coated pipes. Figure 7B shows a total elapsed time of 4 seconds. Figure 7C shows a 9-second elapsed time, during which the toothpaste inside the coated pipe slid approximately 10 cm, while the toothpaste inside the uncoated pipe remained at the start line. Figure 7D shows the toothpaste in the coated pipe near the finish line, 1.9 seconds after the start of the experiment. As shown in Figure 7E, after a total elapsed time of 2.1 seconds, the toothpaste in the coated pipe is at the finish line, while the toothpaste in the uncoated pipe remains at the start line. As shown in Figure 7F, after a total elapsed time of 2.4 seconds, the toothpaste in the coated pipe has been expelled from the coated pipe, while the toothpaste in the uncoated pipe remains at the start line. [Table 1]

[0187] The experiment described in connection with Figures 7A-F was performed five times. The length of time it took the toothpaste to travel 20 cm from "start" to "finish" was measured for each trial. The velocity of the toothpaste was also determined. In the coated PVC pipe, the toothpaste averaged 7.54 ± 1.16 cm / sec. In the uncoated PVC pipe, the toothpaste did not move, and therefore the velocity was considered zero. The time and velocity of the toothpaste in the coated pipe are shown in Table 1.

[0188] Example 7

[0189] Figures 8A-B show the results of an injection molding experiment. Two tubes of construction adhesive (Sonolastic® 150 w / VLM Technology) were obtained and their tips were cut to the same ID (7 mm) for dispensing. A solution of HF Diblock and Teflon particles (prepared as described above) was sprayed onto the inside of the tip, which was then impregnated with Galden HT200. Each tube was then weighed. The experiment was performed using a pneumatic caulking gun hooked to a N2 gas cylinder and regulator.

[0190] In one experiment, a 6 mm diameter drill bit was used to puncture each tube, and each was dispensed at three different pressures for 5 seconds. Timing began as soon as sealant began to flow from the bottle. The pressures were 30, 35, and 40 psi. After each dispense, the tube was weighed, and the average mass flow rate was calculated as (mass dispensed) / (dispensing time). The results are summarized in Figures 8A-B. The results show that the coated nozzle exhibited a rate approximately 50% greater than the standard nozzle at the same pressure. Alternatively, for the same mass flow rate, a nozzle with a liquid-impregnated surface required a lower pressure than an uncoated nozzle. For example, in the data presented in the tables and graphs, the flow rates of the coated nozzle at 30 psi and the uncoated nozzle at 35 psi were nearly identical (1.38 g / s for the coated nozzle compared to 1.37 g / s for the uncoated nozzle).

[0191] This represents a 14% reduction in power required (Power Required = (Pressure) x (Mass Flow Rate) / (Density)). The results extend beyond nozzles, but more generally demonstrate that the power required to flow material inside tubes, pipes, channels, etc. can be significantly reduced, where the material contact surfaces have liquid-impregnated surfaces.

[0192] Example 8

[0193] 9A-E show a dust capture experiment on a liquid-impregnated surface. Two approximately 2" squares of PET plastic were cut from a 0.040" thick sheet and weighed. One square was coated with a liquid-impregnated surface containing textured carnauba wax and ethyl oleate, while the other was left uncoated as a control. The coated square was then reweighed to account for the amount of coating.

[0194] Both squares were placed on an aluminum holder inside the glove box, as shown in Figures 9A and 9B. All-purpose flour was then introduced into the glove box, as shown in Figure 9C. Two handfuls of powder were "thrown" together to create a cloud of dust, one in front of the sample and one behind. The part was removed from the box, as shown in Figure 9D. The part was weighed, and the weight gain due to the powder was calculated to be 0.52 g for the liquid-impregnated surface compared to 0.03 g for the uncoated PET surface. The data is shown in Figure 9E.

[0195] Example 9

[0196] Figures 10A-E show the conduit experiments. As shown in Figure 10A, a 6" long, 2" diameter PVC pipe was sawed in half lengthwise to create two "conduits" to mimic chutes used to deliver concrete. The chute on the right in Figures 10A-E was coated with a liquid-impregnated surface of fluorinated wax and Teflon particles (described elsewhere) and impregnated with Galden HT 200. The chute on the left in Figures 10A-E was left uncoated. The chutes were placed side-by-side in a plastic bucket at a 45° angle. Fast-setting concrete was mixed according to the manufacturer's instructions and poured into the uncoated conduit; however, as shown in Figures 10B-E, the uncured concrete stuck to the surface and did not all reach the bottom. Uncured concrete was then poured into the coated conduit. All of the concrete poured into the coated conduit slid down the chute and to the bottom of the conduit, as shown in Figures 10B-E. The concrete that adhered to the uncoated conduit moved at a speed of approximately 20 cm / sec.

[0197] Example 10

[0198] Figures 11A-D show experiments performed to measure the drag force on a metal sphere surface. Typical superhydrophobic surfaces utilize surface irregularities on a low-energy surface to trap air within the irregularities. This air layer can introduce velocity slip with fluid flowing over the irregular features because the air can move freely within the air pockets. This ultimately reduces drag on the flowing fluid in question. Furthermore, because air is easily compressible, these pockets can easily collapse when pressure / force is introduced. We demonstrate this weakness of superhydrophobic surfaces in Figure 11A. Here, a superhydrophobic aluminum sphere (texture generation method described below) was immersed in water, subjected to pressures from 1 to 2 atmospheres, and then depressurized back to 1 atmosphere. The air film collapsed completely at 2 atmospheres and regrown into individual bubbles after depressurization to 1 atmosphere. Once collapsed, the surface is no longer superhydrophobic, and superhydrophobicity cannot be regained after depressurization. This explains why many superhydrophobic surfaces are not robust for industrial / technical applications. Lubricant-impregnated surfaces incorporate a secondary fluid, or lubricant, into the surface asperities instead of air pockets. This lubricant fluid allows for a slip condition with the primary fluid flowing above it, which is even more stable because liquids are nearly incompressible. The degree of slip can be characterized by linearly extrapolating the velocity profile and defining the slip length, b, as the depth from the surface where the profile extrapolates to zero. The balance of shear stresses above and below the interface indicates this.

[0199] To estimate the slip length b of a liquid-impregnated surface, we model the system as shown in the figure. By linearly extrapolating to zero velocity, we find that the slip length is: b=V i / (du x / dy) o equation 1 It can be seen that...

[0200] In the formula, u x is the fluid velocity in the x direction, and V i is the velocity at the oil-water interface, and (du x / dy) o is the velocity gradient just above the liquid-liquid interface. Vi =t(du x / dy) i (where t is the film thickness, and (du x / dy) i is the velocity gradient within the coating.) and substituting this into equation (1), we obtain: b=t(du x / dy) i / (du x / dy) o equation 2 get.

[0201] At the top of the interface, the shear stress is τ o =μ o (du x / dy) o and on the impregnated liquid side of the interface, τ i =μ i (du x / dy) i τ o is τ at the oil-water interface. i must be equal to μ o (du x / dy) o =μ i (du x / dy) i which can be rearranged to: μ o / μ i =(du x / dy) i / (du x / dy) o equation 3 is obtained.

[0202] Substituting this into equation 2, we get b=t(μ o / μ i ) or b / t=μ o / μ i equation 4 is obtained.

[0203] μ o / μ iNote that if μ<1, there is in fact no benefit to the impregnated surface. If this is true, then one would expect a larger slip length to be obtained by simply filling the texture with the external fluid rather than impregnating it (the etched texture effectively means that the object's diameter is simply 2t smaller, resulting in lower drag). If impregnated with a more viscous liquid, the slip length is less than the coating thickness, and therefore the benefit is as if the solid object were smaller by less than t. This theory suggests that the benefit of a liquid-impregnated surface is due to μ o / μ i > 1 is only sufficient (in the context of low drag).

[0204] A sphere falling through a viscous liquid reaches a terminal velocity of V t ~D 2 is defined as: V, but the liquid-impregnated surface effectively reduces the effective diameter of the sphere by 2b, so we more generally define: V t ~(D-2b) 2 can be written as:

[0205] Half-inch diameter aluminum spheres were sonicated with acetone and ethanol to remove dirt / contamination. The spheres were then etched in a 2.5 M HCl solution for approximately 8 minutes at room temperature. After etching, the spheres were first rinsed thoroughly with deionized water and then immersed in boiling deionized water for 20 minutes. Texture was achieved on two length scales: larger asperities on the order of 5-20 microns, and a finer texture on top at the nanometer scale. An image of this texture is shown in Figure 11B. From Equation 4, we estimate that the slip length for a 10 μm asperity is approximately 1.1 mm.

[0206] Three types of samples were tested: regular smooth aluminum spheres, superhydrophobic aluminum spheres, and lubricant-impregnated aluminum spheres, all 0.5" in diameter. The superhydrophobic spheres were textured using the texturing process described above and then treated with a low-energy silane (octadecyltrichlorosilane - OTS). The lubricant-impregnated samples were textured using the texturing process described above, treated with OTS, and finally impregnated with 10 cSt silicone oil by slowly immersing them in a reservoir of lubricant.

[0207] The sample was then carefully lowered into a large bath of glycerin (approximately 1100 cSt). A rectangular container was used to avoid visual distortion of the falling sphere due to the curvature of the container. A pair of sample tweezers was fixed above the container to carefully lower the sample directly downward and into the same place for each trial. This was found to increase the repeatability of the experiment. Water-glycerin mixtures were used to vary the viscosity of the bath liquid from pure water (1 cSt) to pure glycerin (approximately 1100 cSt).

[0208] A high-speed camera was used to capture the sphere falling through the bath liquid, as shown in Figure 11C. When the sphere reaches terminal velocity, the forces on the sphere are balanced (gravity, drag, and buoyancy). The spheres in our experiments generally reach a constant terminal velocity within a few centimeters.

[0209] We were able to demonstrate an increase in terminal velocity (reduction in drag) of a falling aluminum sphere by utilizing an impregnated lubricant in the texture of the sphere, as shown in FIG. 11D.

[0210] Example 11

[0211] FIG. 12 shows two experiments performed to measure the wetting behavior on metal sphere surfaces. The experiments were performed with three spheres. The first sphere was a sphere with a smooth surface ("normal"). The second sphere was a sphere with an outer textured surface ("OTS"). The third sphere consisted of a sphere with a liquid-impregnated outer surface ("LTS"). In the first experiment, each sphere was partially immersed in water as shown in FIG. 12. In the second experiment, each sphere was immersed in water as shown in FIG. 12. The wetting behavior of each sphere is shown in FIG. 12.

[0212] Example 12

[0213] 13A and 13B show experimental measurements of the clarity of a contact lens having a liquid-encapsulated surface as compared to the clarity of a conventional uncoated contact lens.

[0214] Two Acuve Oasys contact lenses with a base curve radius of 8.4 mm, a diameter of 14 mm, and a power of -0.75 diopters were used in this experiment and labeled Lens 1302 and Lens 1304. Lenses 1302 and 1304 were immersed in saline solution. Using tweezers, lenses 1302 and 1304 were removed from the saline solution and blown dry with nitrogen gas. A carnauba wax suspension was sprayed onto the inner and outer surfaces of lens 1304, while lens 1304 was held at least 12 inches from the spray nozzle to minimize spray force on the lens and ensure a uniform coating. Nitrogen gas was then blown across lens 1304 to allow time for the coating to dry before the ethyl oleate was applied. Ethyl oleate was subsequently sprayed onto the interior and exterior surfaces of lens 1304 while holding lens 1304 at least 12 inches from the spray nozzle to minimize spray force on the lens and ensure a uniform coating. Finally, contact lenses 1302 and 1304 were placed on a notebook page 1306 to provide a background to demonstrate the transparency of the coating, and photographs of Figures 13A and 13B were taken. Figure 13B is a magnified version of the image in Figure 13A.

[0215] In this experiment, contact lenses 1304 coated with a liquid-impregnated surface containing carnauba wax and ethyl oleate demonstrated transparency when placed on a notebook page 206. Words were clearly visible through the transparent coating (see Figures 13A and 13B).

[0216] Contact angle measurements were performed on both the uncoated lens 1302 and the coated contact lens 1304. A droplet deposited on the untreated contact lens 1302 was gradually absorbed onto the surface, indicating that water did not slide across the surface. Instead, the deposited droplet was absorbed. As the contact lens completely covered the surface of the lens 1304 with the liquid-impregnated surface coating, the substrate material of the lens 1304 is believed to have no substantial effect on the roll-off angle (i.e., slipperiness) of the surface.

[0217] Coating performance was measured by depositing carnauba wax on a glass slide and measuring the roll-off angle of a 5-microliter drop of water on the slide. The roll-off angle was measured using a Ramehart goniometer. The roll-off angle was measured to be approximately 3°. This low roll-off angle demonstrates the ease with which water, which has similar properties to disrupt the sliding of fluids on liquid-impregnated surfaces, can be used.

Claims

[Claim 1] A composition as described in the specification.

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