KR102603146B1 - Coating method for water repellent surface - Google Patents

Abstract

The present invention relates to a water repellent composition comprising a fluorine source, a silicon-containing compound or a tin-containing compound, and at least one organic solvent. According to the present invention, water-repellent surface treatment with high heat resistance and environmental friendliness while maintaining super water-repellent properties is possible.

Description

Coating method for water repellent surface}

The present invention relates to a method of forming a water-repellent surface that can be used at high temperatures and has improved durability and stability.

The water-repellent property that reduces contact with water on the surface is a property resulting from chemical properties with low surface energy and a surface structure with a small contact area. A lot of research is underway on technologies that can be applied to a variety of areas, from exterior materials (self-cleaning of windows and doors, etc.) to industrial transportation/plants (enhancing visibility of automobiles, ships, and aircraft, anti-fouling, anti-icing, etc.).

However, most existing technologies use a method of coating fluorine organic compounds (perfluorinated compounds (Teflon)) or silicone organic compounds, either singly or in combination, so they can be used for long periods of time and in various environments (including high temperature, high pressure, etc.). There are problems with durability and stability when applying it. In particular, perfluorinated compounds (Teflon) decompose at 200°C, causing fatal risks to the environment and the human body. At the 4th meeting of the Stockholm Convention in 2009, perfluorinated compounds such as PFOS/PFOSF substances were classified as restricted substances, and in 2013, 5 At the 11th meeting of the Basel Convention in March, unenvironmental issues have been raised, including the resolution of technical guidelines for environmentally sound management of wastes containing perfluorinated compounds.

Accordingly, it is essential to develop a new, eco-friendly, water-repellent surface treatment technology that can be used at high temperatures and has improved durability and stability.

One object of the present invention is to provide a method for forming a water-repellent surface with high heat resistance and environmental friendliness.

Another object of the present invention is to provide a method of forming a water-repellent surface using a precursor.

Another object of the present invention is to provide a method of forming an environmentally friendly water-repellent surface with improved durability and stability.

The technical problems to be achieved by the water repellent composition according to the technical idea of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

This is explained in detail as follows. Meanwhile, each description and embodiment disclosed in the present application may also be applied to each other description and embodiment. That is, all combinations of the various elements disclosed in this application fall within the scope of this application. Additionally, the scope of the present application cannot be considered limited by the specific description described below.

In order to achieve the above object, according to an embodiment of the present invention, a fluoride source; At least one compound selected from the group consisting of silicon-containing compounds and tin-containing compounds; and at least one organic solvent.

According to one embodiment, the silicon-containing compound may include a compound represented by the following chemical formula:

(R ¹ ) _n Si(OR ² ) _4-n

In the formula, R ¹ is a substituted or unsubstituted alkyl group or an aryl group having 1 to 4 carbon atoms, R ² represents an alkyl group having 1 to 4 carbon atoms, R ¹ and R ² may be the same or different, and n is It is an integer from 0 to 2.

According to one embodiment, the silicon-containing compound is tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetraisopropoxysilane ( tetraisopropoxysilane, methoxytriethoxysilane, dimethoxydiethoxysilane, ethoxytrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane , ethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, tetramethoxymethylsilane, tetramethoxyethylsilane ( It may include at least one selected from the group consisting of tetramethoxyethylsilane) and tetraethoxymethylsilane.

According to one embodiment, the tin-containing compound may include a compound represented by the following formula:

Sn(OR) ₂ (ORN) ₂

In the formula, R is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms.

According to one embodiment, the tin-containing compound is tin acetate, tin diacetate, dibutyl tin acetate, tin butoxide, and tin acetylacetonate. It may include at least one selected from the group consisting of acetylacetonate, tin hexafluoroacetylacetonate, tin bis(acetylacetonate), and tin chloride.

According to one embodiment, the fluorine source is ammonium fluoride, ammonium bifluoride, hydrogen fluoride, potassium fluoride, and sodium fluoride. fluoride), tetraalkylammonium difluorides ((R) ₄ NHF ₂ , where R is methyl, ethyl, butyl, phenyl or a fluorinated C _l -C ₄ alkyl group), alkyl phosphonium difluoride (alkyl phosphonium difluorides) ((R) ₄ PHF ₂ , where R is methyl, ethyl, butyl, phenyl or a fluorinated C _l -C ₄ alkyl group), triethylamine trihydrofluoride and fluoride It may include at least one selected from the group consisting of fluorosilicic acid.

According to one embodiment, the organic solvent is ethanol, 2-butanol, 1,4-butanediol, 1,3-butanediol, Ethylene glycol, propylene glycol, N-methyl-2-pyrrolidone, DMSO, r-butyrolactone, propylene glycol monomethyl Ether, propylene glycol monomethyl ether acetate, diethyleneglycol monobenzylether, ethyl lactate, ammonium lactate and dimethyl It may include at least one selected from the group consisting of acetamide (dimethyl acetamide).

According to one embodiment, the volume ratio of at least one compound selected from the group consisting of the silicon-containing compound and the tin-containing compound: the fluorine source: the organic solvent may be 1:1 to 5:20 to 50.

In order to achieve the above object, according to an embodiment of the present invention, preparing a mixture by mixing a fluorine source with at least one compound selected from the group consisting of a silicon-containing compound and a tin-containing compound; Preparing a precursor by dissolving the mixture in an organic solvent; and coating the surface of the article using the precursor.

According to one embodiment, preparing the mixture may further include mixing a metal compound. According to one embodiment, the metal compound may be at least one compound selected from the group consisting of nickel, zirconium, molybdenum, chromium, titanium, and hafnium.

In order to achieve the above object, according to an embodiment of the present invention, a suspension plasma spray coating or an atmospheric pressure DBD (Dielecric Barrel Discharge) plasma coating method is used to prepare an article using a precursor-based water repellent composition. Provides a method for treating surfaces.

According to one embodiment, the products require water-repellent properties, such as heat exchangers, exterior exteriors of automobiles or shipbuilding, frying pans or rice cookers, pipes or insulation materials of plants, solar cells, smartphones, touch panels, secondary batteries, displays, etc. It can be applied and used in a variety of applications.

In order to achieve the above object, according to one embodiment of the present invention, an article with a water-repellent surface treatment using a precursor and a fluorine source compound is provided.

According to one embodiment of the present invention, a super water-repellent surface with thermal stability that maintains water repellency even at 500° C. or higher can be formed.

According to one embodiment of the present invention, a superhydrophobic surface having a contact angle of 150° or more can be formed.

Additionally, according to one embodiment of the present invention, environmentally friendly water-repellent surface treatment is possible due to the inorganic-based composition that does not contain perfluorinated compounds.

However, the effects that can be achieved by the water repellent composition according to an embodiment of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

In order to more fully understand the drawings cited in this specification, a brief description of each drawing is provided.
1 is a diagram showing an article surface-treated using a method for forming a water-repellent surface according to an embodiment of the present invention.
Figure 2 is a diagram showing an electron micrograph of a surface treated by a method for forming a water-repellent surface according to an embodiment of the present invention and an element distribution chart analyzed by EDAX.
Figure 3 is a diagram showing the surface XPS spectrum of an article surface-treated using a water repellent composition according to an embodiment of the present invention.
Figure 4 is a photograph of an article surface-treated using a water repellent composition according to an embodiment of the present invention and an article before treatment placed in an aqueous solution containing methylene blue, showing (a) a sus substrate before treatment; (b) A drawing showing the sus substrate after processing.
Figure 5 shows the contact angle on (a) the coating film of an article surface-treated using a water repellent composition according to an embodiment of the present invention; (b) This is a diagram showing the contact angle after annealing at 500°C for 1 hour.
Figure 6 is a diagram showing the surface

The invention disclosed in this specification can be subject to various changes and may have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail through detailed description. However, this is not intended to limit the technology disclosed in this specification to specific embodiments, and the technology disclosed in this specification should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

In describing the invention disclosed in this specification, if it is determined that a detailed description of related known technology may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, numbers (eg, first, second, etc.) used in the description of this specification are merely identifiers to distinguish one component from another component.

In the present disclosure, when a member is said to be located “on” another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members.

In the disclosure of this specification, when a part “includes” a certain element, this means that it may further include other elements rather than excluding other elements unless otherwise stated.

As used herein, the terms “about,” “substantially,” and the like are used to mean at or close to a numerical value when manufacturing and material tolerances inherent in the stated meaning are given, and are used to convey the meaning of the present disclosure. Precise or absolute figures are used to assist in preventing unscrupulous infringers from taking unfair advantage of stated disclosures.

As used in the present disclosure, the terms “step of” or “step of” do not mean “step for.”

In the present disclosure, the term "substitution" means changing a hydrogen atom bonded to a carbon atom of a compound to another substituent, and the position to be substituted is not limited as long as it is the position where the hydrogen atom is substituted, that is, a position where the substituent can be substituted, 2 In the case of more than one substitution, two or more substituents may be the same or different from each other.

In the present disclosure, the term “substituted or unsubstituted” refers to deuterium (-D); halogen group; Nitrile group; nitro group; hydroxyl group; silyl group; boron group; Alkoxy group; Alkyl group; Cycloalkyl group; Aryl group; and a heterocyclic group, or is substituted with a substituent in which two or more of the above-exemplified substituents are linked, or does not have any substituent. For example, “a substituent group in which two or more substituents are connected” may be a biphenyl group. That is, the biphenyl group may be an aryl group, or it may be interpreted as a substituent in which two phenyl groups are connected.

In the present disclosure, “halo” or “halogen” refers to bromo (Br), chloro (Cl), fluoro (F), or iodo (I), and the preferred halogen as a substituent is fluoro or It could be chloro.

In the disclosure of this specification, “alkyl group” refers to a saturated aliphatic hydrocarbon group such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, and tert-butyl group, which is a substituent. You don't have to have it even if you have it. There is no particular limitation on the additional substituent when substituted, and examples include alkyl group, halogen, aryl group, heteroaryl group, etc. This point is also common to the description below. Additionally, the number of carbon atoms in the alkyl group is not particularly limited, but is preferably in the range of 1 to 10, more preferably 1 to 4, from the viewpoint of availability and cost.

In the disclosure of this specification, “aryl group” refers to an aromatic hydrocarbon group such as phenyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, anthracenyl group, pyrenyl group, and fluoranthenyl group, which is It may or may not have a substituent. The number of carbon atoms in the aryl group is not particularly limited, but is preferably in the range of 6 to 40, and more preferably in the range of 6 to 24. Specific examples of the aryl group are preferably phenyl group, 1-naphthyl group, and 2-naphthyl group.

In the disclosure of this specification, the term “alkoxy group” refers to a functional group to which an aliphatic hydrocarbon group is bonded through an ether bond, such as a methoxy group, an ethoxy group, or a propoxy group, and this aliphatic hydrocarbon group may have a substituent or not. . The number of carbon atoms in the alkoxy group is not particularly limited, but is preferably in the range of 1 to 10, more preferably in the range of 1 to 4.

In the disclosure of this specification, the term "combination thereof" included in the Markushi format expression means a mixture or combination of one or more components selected from the group consisting of the components described in the Markushi format expression, It means including one or more selected from the group consisting of.

In addition, each of the components described below may additionally perform some or all of the functions of other components in addition to the main functions that each component is responsible for, and some of the main functions of each component may be different from other components. Of course, it can also be performed exclusively by a component.

Expressions such as “first,” “second,” “first,” or “second” used in various embodiments may modify various elements regardless of order and/or importance, and describe the elements. It is not limited. Illustratively, the first component may be renamed to the second component without departing from the scope of the present invention, and similarly, the second component may also be renamed to the first component.

According to one embodiment of the present invention, a fluoride source; metal compounds; and at least one organic solvent.

The water repellent composition may have water repellent or super water repellent properties with a contact angle of 150° or more and a sliding angle of 10° or less. Here, the contact angle refers to the angle formed between the liquid surface and the solid surface where the stationary liquid surface contacts the solid wall. Additionally, the slip angle refers to the tilt angle at which the liquid begins to flow based on the horizontal floor surface.

Since the water-repellent surface can be used as is by dissolving a fluorine source, which is a precursor made only of inorganic substances, and a metal compound in an organic solvent, eco-friendly coating is possible, and at the same time, compared to a water-repellent solution in the form of a slurry in which particles are dispersed in a solvent, the surface of the article is reduced. A more dense super-hydrophobic coating film can be formed and durability is improved. In addition, the water repellent composition not only provides long-term storage stability, but also has excellent water repellency and lubricity in the case of surface-treated articles.

According to one embodiment, the fluorine source is ammonium fluoride (NH ₄ F), ammonium bifluoride ((NH ₄ )HF ₂ ), hydrogen fluoride ( HF), potassium fluoride (KF), sodium fluoride (NF), tetraalkylammonium difluorides ((R) ₄ NHF ₂ , where R is methyl, ethyl, butyl, phenyl or fluorinated C _l -C ₄ alkyl group), alkyl phosphonium difluorides ((R) ₄ PHF ₂ , where R is methyl, ethyl, butyl, phenyl or fluorinated C _l -C ₄ alkyl group), triethylamine trihydrofluoride ((C ₂ H ₅ )3NＢㆍ3HF) and fluorosilicic acid (H ₂ SiF ₆ ). That is not the case.

By containing a fluorine source, the formed water-repellent surface can improve surface lubricity, permeability, film formation, and texture while maintaining water repellency, while lowering surface energy.

According to one embodiment, the metal compound is at least one compound selected from the group consisting of silicon-containing compounds and tin-containing compounds; At least one compound selected from the group of titanium, zirconium and hafnium compounds; It may include non-ferrous metal compounds such as nickel, zirconium, molybdenum, and chromium. The water repellent composition can increase the corrosion resistance, heat resistance, and wear resistance of the water repellent surface by including the metal-containing compound. Exemplarily, the metal compound includes at least one compound selected from the group consisting of silicon-containing compounds and tin-containing compounds. In another example, the metal compound includes a silicon-containing compound.

According to one embodiment, the silicon-containing compound may include a compound represented by the following chemical formula:

(R ¹ ) _n Si(OR ² ) _4-n

In the formula, R ¹ is a substituted or unsubstituted alkyl group or an aryl group having 1 to 4 carbon atoms, R ² represents an alkyl group having 1 to 4 carbon atoms, Si is silicon, O is oxygen, and R ¹ and R ² are It may be the same or different, and n is an integer from 0 to 2.

According to one embodiment, the silicon-containing compound is tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetraisopropoxysilane ( tetraisopropoxysilane, methoxytriethoxysilane, dimethoxydiethoxysilane, ethoxytrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane , ethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, tetramethoxymethylsilane, tetramethoxyethylsilane ( tetramethoxyethylsilane) and tetraethoxymethylsilane (tetraethoxymethylsilane), but is not limited thereto.

According to one embodiment, the tin-containing compound may include a compound represented by the following formula:

Sn(OR) ₂ (ORN) ₂

In the formula, R is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, Sn is tin, O is oxygen, and N is nitrogen.

According to one embodiment, the tin-containing compound is tin acetate, tin diacetate, dibutyl tin acetate, tin butoxide, and tin acetylacetonate. acetylacetonate), tin hexafluoroacetylacetonate, tin bis(acetylacetonate), tin chloride (SnCl ₄ ·5H ₂ O or SnCl ₂ ·2H ₂ O ), but is not limited to this.

According to one embodiment, the organic solvent can be used without limitation as long as it is a material that can dilute and dissolve a metal compound including a precursor fluorine source and a silicon-containing compound or tin-containing compound. Illustratively, the organic solvent is ethanol, 2-butanol, 1,4-butanediol, 1,3-butanediol, ethylene glycol. (ethylene glycol), propylene glycol, N-methyl-2-pyrrolidone, DMSO, r-butyrolactone, propylene glycol monomethyl ether ( propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monobenzylether, ethyl lactate, ammonium lactate and dimethyl acetamide. (dimethyl acetamide), but is not limited thereto.

According to one embodiment, the composition of the solution for forming a precursor-based water-repellent surface may optionally further include a reducing agent. The reducing agent includes sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH ₄ OH), sodium borohydride (NaBH ₄ ), hydrazine (N ₂ H ₄ ), hydriodine (HI), ascorbic acid, Including, but not limited to, reducing organic solvents and mixtures thereof. Illustratively, the reducing agent reduces tin chloride (SnCl ₄ ·5H ₂ O or SnCl ₂ ·2H ₂ O) and may be diluted in ethanol or another organic solvent and included in the water repellent composition.

According to one embodiment, the organic solvent is the metal compound; And it may be included in an amount sufficient to dilute the fluorine source. Exemplarily, the volume ratio of at least one compound selected from the group consisting of the silicon-containing compound and the tin-containing compound: the fluorine source: the organic solvent may be 1: 1 to 5: 20 to 50, preferably , 1: 2 to 3: 30 to 40. The organic solvent may be used by mixing two or more organic solvents. Illustratively, the organic solvent may be a composition in which a small amount of 2-butanol is added, and the solubility of the composition may be improved. In another example, the water repellent composition is tetraethoxysilane (TEOS): fluorosilicic acid (H ₂ SiF ₆ ): ethanol (EtOH): 2-butanol (2-BuOH) in the ratio of 3: 7: 80: 20. It can be included as a volume ratio.

According to one embodiment of the present invention, preparing a mixture by mixing a fluorine source with at least one compound selected from the group consisting of a silicon-containing compound and a tin-containing compound; Preparing a precursor by dissolving the mixture in an organic solvent; and coating the surface of the article using the precursor. According to one embodiment, the coating step may use suspension plasma spray coating or atmospheric pressure DVD plasma coating method.

According to one embodiment, preparing the mixture may further include mixing a metal compound. The metal compound can be used without limitation as long as it is a material that can improve the corrosion resistance, heat resistance, and wear resistance of the water-repellent surface. Illustratively, the metal compound may be nickel, zirconium, molybdenum, chromium, titanium, hafnium, etc.

The present invention can manufacture a water repellent composition solution using a precursor containing a metal and form a water repellent surface through a plasma coating process, thereby suppressing the release of factors harmful to the human body and the environment that may occur from an organic water repellent, and using a water repellent in the form of particles. Compared to , it is easier to manufacture and can form a water-repellent surface with improved durability. In addition, the water repellent composition can be manufactured stably and economically, and has the advantage of excellent adhesion to the surface of the article, excellent water repellency, and excellent surface lubricity.

According to one embodiment of the present invention, a method of treating the surface of an article using the precursor-based water repellent composition solution is provided. For example, a water-repellent coating film may be formed by spraying a coating suspension solution onto a substrate through suspension plasma spray coating. Suspension plasma spray coating is a method similar to existing plasma spraying, but uses suspension or slurry as a coating raw material. In the present disclosure, it can be understood that a precursor-based water repellent composition solution according to an embodiment of the present invention is used as a coating raw material. A thermal spray coating can be formed on a substrate by putting the water repellent composition into a plasma jet and spraying it toward the substrate.

According to one embodiment, in suspension plasma spray coating, heat source gas is changed into a plasma flame by applied current, voltage, and gas injector pressure and is sprayed toward the substrate. The heat source gas may exemplarily include at least one of argon, helium, hydrogen, nitrogen gas, and air, and the flow rate of the heat source gas may be about 5 lpm to about 20 lpm, preferably, argon 20 lpm. , nitrogen 5 lpm can be used.

The applied current may be from about 10 A to about 130 A, the voltage may be from 0.7 kW to 30 kW, and the injector pressure may be from about 0.1 MPa to about 0.3 MPa. Preferably, an injector pressure of 0.1 MPa may be used regardless of the injector. .

Additionally, the distance between the plasma and the surface of the substrate may be about 50 mm to about 200 mm, and preferably the plasma can be sprayed at a distance of 300 mm. The flow rate of the water repellent composition may be from about 5 lpm to about 20 lpm, and a flow rate of 20 lpm is preferably used. Additionally, the coating time may be about 0.5 minutes to about 3.5 minutes, and preferably 1 minute or more.

According to one embodiment of the present invention, a method of treating the surface of an article using the precursor-based water repellent composition solution is provided. For example, a water repellent coating film can be formed by spraying a coating precursor-based water repellent composition solution onto a substrate using atmospheric pressure low temperature plasma coating, that is, atmospheric pressure DBD plasma coating method. Atmospheric pressure low-temperature plasma coating, that is, atmospheric pressure DBD plasma coating method, is a chemical vapor deposition method using plasma discharge generated in the discharge area between DBD (Dielecric Barrel Discharge) coating electrodes while exposed to atmospheric pressure by receiving RF energy. In the present disclosure, it can be understood that a precursor-based water repellent composition solution according to an embodiment of the present invention is used as a coating raw material. A thermal spray coating can be formed on a substrate by spraying the water repellent composition together with a carrier gas through a nozzle.

Examples of articles that can be surface treated using the water repellent composition include heat exchangers, exterior exteriors for automobiles and shipbuilding, frying pans and rice cookers, pipes and insulation materials for plants, solar cells, smartphones, touch panels, and secondary devices. It can be used in a variety of applications that require water-repellent properties, such as batteries (corrosion prevention) and displays (removal of surface impurities, water blocking, and fingerprint prevention).

Additionally, the substrate on which the water-repellent surface is formed with the precursor-based water-repellent composition solution is not particularly limited and may be, for example, metal, glass, ceramic, or plastic.

The present invention will be described in more detail through examples below, but the scope of the present invention is not limited thereto.

(Example)

Preparation of water repellent composition

(1) Example 1

3 mL of tetraethoxysilane (TEOS; manufactured by Sigma Aldrich) was mixed with 7 mL of fluorosilicic acid (H ₂ SiF ₆ ; manufactured by Sigma Aldrich). Then, the mixture was diluted by adding 80 mL of ethanol and 20 mL of 2-butanol mixed solvent to prepare a water repellent composition.

(2) Example 2

1.5 mL of tin chloride (SnCl ₄ ·5H ₂ O; manufactured by Sigma Aldrich) was mixed with 3.5 mL of fluorosilicic acid (H ₂ SiF ₆ ; manufactured by Sigma Aldrich). Then, the mixture was added to 50 mL of ethanol and diluted by further adding 1 N ammonium hydroxide (NH ₄ OH; manufacturer: Sigma Aldrich) to prepare a water repellent composition.

(3) Example 3

4 mL of titanium tetraisopropoxide (TTIP; manufactured by Sigma-Aldrich), 3 mL of tetraethoxysilane (TEOS; manufactured by Sigma-Aldrich) and 7 mL of fluorosilicic acid (H ₂ SiF ₆ ; manufactured by Sigma-Aldrich). : Sigma Aldrich). Then, the mixture was diluted by adding 100 mL of ethanol to prepare a water repellent composition.

Articles treated with water repellent composition

Stainless steel (SUS304 2B product) with a 30 mm square plate and a plate thickness of 0.5 mm was used as the base material for the product. The stainless steel was washed with distilled water and dried with nitrogen gas before use. The water repellent composition prepared in Example 1 was coated on the stainless steel surface dried with nitrogen gas by suspension plasma spray coating. The coating conditions were 0.1 MPa injector pressure, 20 lpm of heat source gas, 5 lpm of N ₂ , 300 mm distance from the substrate, and 20 lpm water repellent composition flow rate for 1 minute.

Figure 1 shows stainless steel surface treated using the water repellent composition prepared in Example 1. Figure 2 shows EDAX elemental analysis of stainless steel on which the water-repellent surface was formed. It can be seen that the fluorine element is distributed uniformly throughout. Figure 3 shows an . In Figure 4, it can be seen that the stainless steel floats without being wet with water due to the water-repellent coating on the surface.

Water repellency and heat resistance evaluation

The stainless steel surface-treated using the water repellent composition prepared in Example 1 was annealed at room temperature and 500° C. for 1 hour, and then the contact angle was measured with a contact angle meter (measured with DMO-501; manufacturer: Kyohwa Corporation, Japan).

Figure 5 shows the contact angle on (a) the coating film of stainless steel surface treated using the water repellent composition prepared in Example 1; (b) Shows the contact angle after annealing at 500°C for 1 hour. As can be seen in Figure 5, it maintains superhydrophobic properties with a contact angle of 150 degrees or more even at a temperature of 500°C or higher, thereby forming a highly heat-resistant superhydrophobic surface.

Figure 6 shows the XPS spectrum of the surface of stainless steel coated with the water repellent composition after annealing at 500°C for 1 hour. The contact angle was maintained even after annealing at 500°C, but XPS analysis showed that some of the fluorine elements were decomposed and the fluorine content was reduced. Through this, it can be seen that SiO and F chemically bonded to form a film.

Above, the technology disclosed in this specification has been described in detail with preferred embodiments, but the technical idea of the present invention is not limited to the above embodiments, and is within the scope of the technical idea of the present invention. Various modifications and changes are possible depending on the user.

Claims (15)

fluoride source;
silicon-containing compounds; and
A water repellent composition comprising at least one organic solvent,
The water repellent composition wherein the volume ratio of the fluorine source: the silicon-containing compound: the organic solvent is 1 to 5: 1: 20 to 50. According to claim 1,
A water repellent composition, wherein the silicon-containing compound includes a compound represented by the following formula:
(R ¹ ) _n Si(OR ² ) _4-n
(Wherein, R ¹ is a substituted or unsubstituted alkyl group or an aryl group having 1 to 4 carbon atoms, R ² represents an alkyl group having 1 to 4 carbon atoms, R ¹ and R ² may be the same or different, and n is an integer from 0 to 2). According to claim 1,
The silicon-containing compounds include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetraisopropoxysilane, and methoxytri. Ethoxytriethoxysilane, dimethoxydiethoxysilane, ethoxytrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane (ethyltriethoxysilane), dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, tetramethoxymethylsilane, tetramethoxyethylsilane and tetraethoxy A water repellent composition comprising at least one selected from the group consisting of methylsilane (tetraethoxymethylsilane). According to claim 1,
The composition further comprises a tin-containing compound,
A water repellent composition, wherein the tin-containing compound includes a compound represented by the following formula:
Sn(OR) ₂ (ORN) ₂
(In the formula, R is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms). According to claim 4,
The tin-containing compounds include tin acetate, tin diacetate, dibutyl tin acetate, tin butoxide, tin acetylacetonate, and tin hexafluoride. A water repellent composition comprising at least one selected from the group consisting of tin hexafluoroacetylacetonate, tin bis(acetylacetonate), and tin chloride. According to claim 1,
The fluorine source is ammonium fluoride, ammonium bifluoride, hydrogen fluoride, potassium fluoride, sodium fluoride, and tetraalkylammonium. tetraalkylammonium difluorides ((R) ₄ NHF ₂ , where R is methyl, ethyl, butyl, phenyl or a fluorinated C _l -C ₄ alkyl group), alkyl phosphonium difluorides ( (R) ₄ PHF ₂ , where R is methyl, ethyl, butyl, phenyl or fluorinated C _l -C ₄ alkyl group), triethylamine trihydrofluoride and fluorosilicic acid. A water repellent composition comprising at least one selected from the group consisting of. According to claim 1,
The organic solvent is ethanol, 2-butanol, 1,4-butanediol, 1,3-butanediol, and ethylene glycol. , propylene glycol, N-methyl-2-pyrrolidone, DMSO, r-butyrolactone, propylene glycol monomethyl ether ), propylene glycol monomethyl ether acetate, diethyleneglycol monobenzylether, ethyl lactate, ammonium lactate and dimethyl acetamide. A water repellent composition comprising at least one selected from the group consisting of. delete preparing a mixture by mixing a fluorine source with a silicon-containing compound;
Preparing a precursor by dissolving the mixture in an organic solvent; and
A method of forming a water-repellent surface, comprising coating the surface of an article using the precursor,
A method of forming a water-repellent surface, wherein the volume ratio of the fluorine source: the silicon-containing compound: the organic solvent is 1 to 5: 1: 20 to 50. According to clause 9,
A method of forming a water-repellent surface, wherein the silicon-containing compound includes a compound represented by the following formula:
(R ¹ ) _n Si(OR ² ) _4-n
(Wherein, R ¹ is a substituted or unsubstituted alkyl group or an aryl group having 1 to 4 carbon atoms, R ² represents an alkyl group having 1 to 4 carbon atoms, R ¹ and R ² may be the same or different, and n is an integer from 0 to 2). According to clause 9,
The step of preparing the mixture further includes mixing a tin-containing compound,
A method of forming a water-repellent surface, wherein the tin-containing compound includes a compound represented by the following formula:
Sn(OR) ₂ (ORN) ₂
(In the formula, R is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms). According to clause 9,
The step of preparing the mixture further includes mixing a metal compound,
A method of forming a water-repellent surface, wherein the metal compound is at least one compound selected from the group consisting of nickel, zirconium, molybdenum, chromium, titanium, and hafnium. According to clause 9,
A method of forming a water-repellent surface, wherein the coating step uses suspension plasma spray coating. According to clause 9,
A method of forming a water-repellent surface, wherein the coating step uses atmospheric pressure DVD plasma coating. An article surface-treated using the water repellent composition according to any one of claims 1 to 7.