KR20200026658A - Composition for super-hydrophobic coating, method for manufacturing thereof, super-hydrophobic coating layer formed using the same and method for manufacturing super-hydrophobic coating layer using the same - Google Patents

Abstract

The present invention relates to a composition for super water-repellent coating and, more specifically, to a composition for super water-repellent coating, which has excellent adhesion to an adhered surface as it is chemically bonded to the adhered surface, is capable of forming a thin and uniform coating layer while having super water-repellent properties, and has excellent in water resistance and electrical conductivity, to a manufacturing method thereof, and to a method of forming a super water-repellent coating layer therethrough.

Description

Composition for super-hydrophobic coating, method for manufacturing conjugate, super-hydrophobic coating layer formed using the same and method for manufacturing super-hydrophobic coating layer using the same}

The present invention relates to a composition for super water-repellent coating, and more particularly, it has excellent adhesion to the adhered surface by chemically bonding to the adhered surface, has a super water-repellent property, and enables the formation of a thin and uniform coating layer. It relates to a super water-repellent coating composition having excellent conductivity, a method for preparing the same, a super water-repellent coating layer formed through the same and a method for forming the same.

When water droplets contact a solid surface, the contact angle of water droplets is defined as hydrophobicity in the range of 70 to 150 °, and superhydrophobicity when it is 150 ° or more. In particular, on a solid surface with a contact angle of 160 ° or more, the water droplets roll on the surface, leaving no trace of contact with the water. Having superplastic and super water-repellent surfaces demonstrates the ability of self-cleaning to easily flush surfaces with a small amount of water. Super water-repellent surfaces also have a slip angle of less than 10 °, which can cause water to roll off easily with slight inclination. In addition, when the surface is submerged in water, the coating surface may contain bubbles, which may cause drag reduction on the surface, thereby improving water flow characteristics.

The surface of the lotus leaf in its natural state has a super water-repellent surface, which can form a super water-repellent surface through the pattern of micro and nano structure and low surface energy. Such super water-repellent surfaces are widely used in various fields such as electronic components, building materials, cosmetics, and functional fibers.

In order to realize the super water-repellent surface, nanoparticle adsorption by self-assembly, polymer phase separation, micelle application or sol-gel coating method of nanoparticles is mainly used, which is time-consuming and expensive. This difficulty makes it difficult to use throughout the industry. In addition, the durability and water resistance of the resulting coating layer is difficult to operate stably, despite the possibility of active use is difficult.

Meanwhile, in order to solve the problem that carbon nanoparticles are entangled with carbon nanoparticles in a composite material due to strong van der Waals forces due to strong interactions inside the material, it is difficult to uniformly arrange them on a substrate. Acid etching, plasma treatment, or vapor deposition produce special functional groups on the surface of the particles to facilitate dispersion in solution. To do this, the size of the substrate can be limited, and special equipment is used.

Inexpensive and easily accessible in the industry can be achieved by applying ultra sonication and a suitable dispersant to ensure stable dispersion in solution. The coating is made on the substrate using a conductive and super water-repellent coating solution prepared by dispersing in various ways. The fundamental problem of this coating is that it is very vulnerable to the external impact of the coating layer.

Conventional techniques form coating layers in a manner that is difficult or complex to use intuitively in the industry to implement superhydrophobic surfaces. In order to form this coating layer, expensive materials or expensive materials are often used to make use of expensive equipment and physical properties. Expensive equipment and materials can produce super water-repellent surfaces, but they pose a major obstacle to industrial use. Recently, the formation of a conductive super water-repellent coating layer using various methods has been successful, but there is still a limit to the durability of the coating film.

Accordingly, it is urgent to develop a super water-repellent coating composition having excellent adhesion to the adhered surface, having super water repellency, forming a thin and uniform coating layer, and having excellent water resistance and electrical conductivity, by chemically bonding to the adhered surface. to be.

KR 10-2005-0095459 A (published: September 29, 2005)

The present invention has been made to solve the above-described problems, and as the chemically bonded to the adhered surface, the adhesion to the adhered surface is excellent, super water repellency, thin and uniform coating layer can be formed and water resistance and electrical conductivity It is an object to provide an excellent super water-repellent coating composition, a method for preparing the same, a super water-repellent coating layer formed through it and a method for forming the same.

The present invention to solve the above problems, a binder comprising a main resin and a metal-based coupling agent; Conductive fillers; It provides a composition for super water-repellent coating comprising a; and a coating stabilizer.

According to an embodiment of the present invention, the metal coupling agent is a zirconium (Zr) coupling agent, an aluminum (Al) coupling agent, a zirco aluminate (Al / Zr) coupling agent and a titanium (Ti) coupling It may include one or more selected from the group consisting of zero.

In addition, the zirco aluminate (Al / Zr) -based coupling agent may include a compound represented by the following formula (1).

[Formula 1]

In Formula 1, R ¹ and R ² are each independently a straight alkyl group of C1 ~ C5, C3 ~ C6 crushed alkyl group, C1 ~ C5 straight alkenyl group, C3 ~ C6 Crushed alkenyl group, amino group , A chloro group (-Cl), a carboxy group (-COOH), an epoxy group, a methacrylooxy group, a C1-C5 straight alkoxy group, a C3-C6 crushed alkoxy group, or a C1-C3 alkoxyalkoxy group. .

In addition, the binder may include 0.2 to 2.5 parts by weight of the metal-based coupling agent based on 100 parts by weight of the main resin.

In addition, the conductive filler containing at least one selected from the group consisting of carbon nanotubes, silver (Ag) nanowires, graphene, carbon black, silver (Ag) particles and carbon fiber with respect to 100 parts by weight of the main resin It may include 3 to 50 parts by weight, and SiO ₂ , ZrO ₂ , Al ₂ O ₃ , TiO ₂ And it may include 3 to 35 parts by weight of a coating stabilizer comprising at least one selected from the group consisting of carbon black.

The solvent may further include 4,000 to 21,000 parts by weight of the solvent based on 100 parts by weight of the main resin, and may further include 0.05 to 0.8 parts by weight of the dispersant.

In addition, when the Raman spectrum is measured by the following measurement method, peaks may exist at wavenumbers 800 to 900 cm ⁻¹ and wavenumbers 1675 to 1775 cm ⁻¹ .

[How to measure]

The super water-repellent coating composition was coated on the pretreated treated surface, and heat-treated to form a super-water repellent coating layer, and then the Raman spectrum was measured.

On the other hand, the present invention is a binder containing a main resin and a metal coupling agent; Conductive fillers; And a coating stabilizer; provides a super water-repellent coating layer formed.

On the other hand, the present invention comprises the steps of preparing a first solution containing a conductive filler; Preparing a second solution by mixing a coating stabilizer with the first solution; It provides a method for producing a composition for super water-repellent coating comprising a; and a third solution to prepare a third solution by mixing a binder containing a metal coupling agent and a main resin in the second solution.

On the other hand, the present invention comprises the steps of pre-treating the adherend surface; Coating a super water-repellent coating composition according to any one of claims 1 to 7 on the pretreated treated surface; It provides a super water-repellent coating layer forming method comprising; and heat-treating the composition for super water-repellent coating coated on the adhered surface.

The super water-repellent coating composition of the present invention, a method for preparing the same, a super water-repellent coating layer formed through it, and a method for forming the same are excellent in adhesive strength with the adhered surface by chemically bonding to the adhered surface, and at the same time thin and uniform. It is possible to form a coating layer has excellent effects of water resistance and electrical conductivity.

Accordingly, it can be applied to the separator plate of the fuel cell to prevent performance degradation of the fuel cell, or can be applied to various fields such as electromagnetic shielding, ice making, ice protection, and resistance heating element.

1 is a schematic diagram showing a chemical bond between the metal filler and the adhered surface provided in the superhydrophobic coating composition according to an embodiment of the present invention,
Figure 2 is a schematic diagram showing a method of forming a super water-repellent coating layer according to an embodiment of the present invention,
3 is a view showing the adhesive force according to the content of the metal-based fillers provided in the superhydrophobic coating composition according to an embodiment of the present invention,
Figure 4 is a Raman spectroscope (spectroscope) showing the chemical bond between the super water-repellent coating layer and the adhered surface according to an embodiment of the present invention,
5 is a SEM image of the super water-repellent coating layer according to an embodiment of the present invention,
Figure 6 is a graph of the contact angle and the sliding angle of the super water-repellent coating layer according to whether the coating stabilizer included in the composition for super water-repellent coating according to an embodiment of the present invention
7 is an electromagnetic shielding performance graph according to the thickness of the super water-repellent coating layer according to an embodiment of the present invention,
8 is a photograph showing a change in contact angle after performing a pretreatment step according to an embodiment of the present invention;
9 is a schematic diagram showing functional group generation when performing a pretreatment step according to an embodiment of the present invention;
10 is a graph showing the degree of adhesion improvement when performing the pretreatment step and the inclusion of the metal-based coupling agent in the composition for the super water-repellent coating according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

The superhydrophobic coating composition according to the present invention includes a binder containing a main resin and a metal coupling agent; Conductive fillers; And a coating stabilizer.

First, the binder containing a main resin and a metallic coupling agent is demonstrated.

The main resin is included in the binder to perform a function of supporting the super water-repellent coating layer.

The main resin may be used without limitation as long as it is a resin commonly used in the art, preferably polydimethylsiloxane (PDMS), polyimide (PI), polypropylene (PP), polymethyl methacrylate (PMMA) , Polyurethane (PU), polyethylene (PE), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyethersulfone (PES) and polychlorotrifluoroethylene (PCTFE) It may include one or more, more preferably may include one or more selected from the group consisting of polydimethylsiloxane (PDMS), polyimide (PI) and polypropylene (PP), more preferably poly Dimethylsiloxane (PDMS). In this case, when the polydimethylsiloxane (PDMS) is used as the main resin as an example, the main resin may include a monomer and a curing agent, but is not limited thereto.

In addition, the metal-based coupling agent by coating the composition for the super water-repellent coating on the surface to be adhered to form a super water-repellent coating layer to significantly improve the adhesive strength through the combination with the adhered surface, and performs a function to improve the water resistance in water.

Specifically, the reason why the adhesive strength is improved when the metal coupling agent is used is because the metal coupling agent serves as a bridge that chemically bonds the superficial water repellent coating layer formed of the composition for the superficial water repellent coating and the surface as shown in FIG. 1. When forming a super water-repellent coating layer after coating the composition for super water-repellent coating, a compound bond as shown in FIG. 1 occurs.

The metal coupling agent may be used without limitation as long as it is a metal coupling agent that can be used conventionally, and preferably a zirconium (Zr) coupling agent, an aluminum (Al) coupling agent, a zirco aluminate (Al / Zr) coupling At least one selected from the group consisting of a ring agent and a titanium (Ti) coupling agent, a silicon (Si) coupling agent, and a zinc (Zn) coupling agent, and more preferably a zirconium (Zr) coupling agent, At least one selected from the group consisting of an aluminum (Al) -based coupling agent, a zirco aluminate (Al / Zr) -based coupling agent, and a titanium (Ti) -based coupling agent may be used, and more preferably zirconium (Zr) -based Using at least one member selected from the group consisting of a coupling agent, an aluminum (Al) -based coupling agent, and a zirco aluminate (Al / Zr) -based coupling agent may be more advantageous for improving adhesion between the adherend and the superhydrophobic coating layer. .

As an example of a zirco aluminate (Al / Zr) coupling agent and a zirconium (Zr) coupling agent that can be used as the metal-based coupling agent, a coupling agent such as the following formula (1) or (2) may be used, in this case, It may be more advantageous to improve the adhesion between the adhered surface and the super water-repellent coating layer.

[Formula 1]

In this case, in Formula 1, R ¹ and R ² are each independently a C1 ~ C5 linear alkyl group, C3 ~ C6 crushed alkyl group, C1 ~ C5 linear alkenyl group, C3 ~ C6 crushed alkenyl group, Amino group, chloro group (-Cl), carboxy group (-COOH), epoxy group, methacrylooxy group, C1-C5 linear alkoxy group, C3-C6 crushed alkoxy group, or C1-C3 alkoxyalkoxy group Can be. Further, more preferably, R ¹ and R ² are each independently C 1 ~ C 5 linear alkenyl group, C 3 ~ C 6 Crushed alkenyl group, amino group, chloro group (-Cl), carboxy group (-COOH), It may be an epoxy group, a methacrylooxy group, a methoxy group, or a methoxyethoxy group.

In this case, each alkoxy group provided in the alkoxyalkoxy group may be the same or different from each other, for example, the alkoxyalkoxy group may be a methoxymethoxy group or a methoxyethoxy group.

In addition, in order to improve the bonding force with the organic material, R ¹ and R ² are each independently C 1 ~ C 5 linear alkenyl group, C 3 ~ C 6 Crushed alkenyl group, amino group, chloro group (-Cl), carboxy group (-COOH), an epoxy group, or a methacrylooxy group, in order to improve the bonding strength with the inorganic material, R ¹ and R ² are each independently a chloro group (-Cl), C1 ~ C5 linear alkoxy Group, C3 to C6 crushed alkoxy group, carboxy group (-COOH), or C1 to C3 alkoxyalkoxy group.

[Formula 2]

On the other hand, the binder may include 0.2 to 2.5 parts by weight, preferably 0.3 to 2 parts by weight of the metal-based coupling agent with respect to 100 parts by weight of the main resin. If the content of the metal-based coupling agent included in the binder is out of the range may cause a problem that the adhesion to the adhered surface is not good.

Next, the conductive filler will be described.

The conductive filler performs a function of improving the electrical conductivity when forming a super water-repellent coating layer by coating the super water-repellent coating composition on the adhered surface.

The conductive filler may be used without limitation as long as it is a conductive filler commonly used in the art, preferably carbon nanotubes, silver (Ag) nanowires, ketjen carbon black, graphene, silver (Ag) particles And it may include one or more selected from the group consisting of carbon fibers, more preferably may include one or more selected from the group consisting of carbon nanotubes and silver (Ag) nanowires.

In this case, the carbon nanotubes may use single-walled or multi-walled carbon nanotubes, and the conductive filler may be carbon nanotubes or silver nanowires having an aspect ratio of 40 to 5500, preferably 50 to 5000, but is not limited thereto. It is not.

On the other hand, the superhydrophobic coating composition according to the present invention may include 3 to 50 parts by weight, preferably 5 to 45 parts by weight of the conductive filler with respect to 100 parts by weight of the main resin. If the conductive filler is less than 3 parts by weight with respect to 100 parts by weight of the main resin, the electrical conductivity may not be good, and if the conductive filler is more than 50 parts by weight, it may interfere with bonding to the adhered surface. The adhesive force with the adherend cannot be expressed.

Next, the coating stabilizer will be described.

The coating stabilizer helps to form the surface and performs a function of expressing super water repellency as showing a stable microstructure.

The coating stabilizer can be used without limitation as long as it is a material that can be commonly used in the coating stabilizer in the art, preferably SiO ₂ , ZrO ₂ , Al ₂ O ₃ , TiO ₂ And it may include one or more selected from the group consisting of carbon black.

In addition, the coating stabilizer may include at least one selected from the group consisting of first particles having an average particle diameter of 7 to 30 nm and second particles having an average particle diameter of 50 to 200 nm, and preferably having an average particle diameter of It may include one or more selected from the group consisting of first particles of 8 to 25nm and second particles of 55 to 190nm in average diameter, but is not limited thereto.

On the other hand, the composition for superhydrophobic coating according to the present invention may include 3 to 35 parts by weight of the coating stabilizer, preferably 5 to 30 parts by weight, based on 100 parts by weight of the main resin. If the coating stabilizer is less than 3 parts by weight based on 100 parts by weight of the main resin, it may be difficult to form a stable conductive super water-repellent structure. If the content exceeds 35 parts by weight, the adhesion to the surface to be deposited may be reduced.

Meanwhile, the superhydrophobic coating composition according to the present invention may further include a dispersant and a solvent.

The dispersant serves to prevent the particles dispersed in the composition from agglomerating with van der Waals attraction and to organically bond with the main resin.

The dispersant may be used without limitation as long as it is a substance that can be used in the dispersant in the art, preferably Triton X-100, polyoxyethylene sorbitan mono-oleate and sodium dodecyl sulfate. It may include one or more selected from the group consisting of.

 On the other hand, the super water-repellent coating composition according to the present invention may further comprise 0.05 to 0.8 parts by weight, preferably 0.1 to 0.5 parts by weight based on 100 parts by weight of the main resin. If the dispersant is less than 0.05 parts by weight based on 100 parts by weight of the main resin, dispersibility may not be improved to a desired level. If the dispersant exceeds 0.8 parts by weight, agglomeration between the dispersants may occur, and thus dispersibility may be reduced. .

In addition, the solvent may be used without limitation so long as it is a substance that can be used in the solvent in the art, preferably water, benzene, toluene, xylene, acetone, hexane, heptane, chlorobenzene, methanol, ethanol, n- Propanol, isopropanol, butanol, pentanol, hexanol, heptanol, octanol, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethyl Formamide, N, N-diethylformamide, N-methylcaprolactam, hexamethylphospholamide, tetramethylenesulfone, dimethylsulfoxide, o-cresol, m-cresol, p-cresol, phenol, p-chlorphenol , 2-chloro-4-hydroxytoluene, diglyme, triglyme, tetraglyme, dioxane, γ-butyrolactone, dioxolane, cyclohexanone, cyclopentanone, dichloromethane, chloroform, 1,2-dichloro Ethane, 1,1,2-trichloroethane, dibromomethane, tribromomethane, 1,2-dibromoethane, 1, It may comprise one or more selected from the group consisting of 1,2-tribromoethane and methyl ethyl ketone (mek), more preferably ethanol, methyl ethyl ketone (mek), chloroform, isopropanol and toluene It may include one or more selected from the group consisting of.

In addition, the superhydrophobic coating composition according to the present invention may further include 4,000 to 21,000 parts by weight, preferably 5,000 to 20,000 parts by weight, based on 100 parts by weight of the main resin. If the solvent is less than 4,000 parts by weight based on 100 parts by weight of the main resin, it may not be easy to form a uniform coating layer. If the solvent is more than 20,000 parts by weight, the solvent may remain, thereby expressing a desired level of adhesive force. You may not be able to.

On the other hand, the composition for superhydrophobic coating according to the present invention may further include additives such as a curing agent, a curing catalyst, and a physical property enhancer, in addition to the above-described configuration, and these may be used without limitation as long as the material can be commonly used in the art. Accordingly, the present invention is not particularly limited thereto.

On the other hand, the composition for superhydrophobic coating according to the present invention, when measuring the Raman spectrum by the following measurement method, wavenumber (wavenumber) 800 ~ 900 cm ^-1 and wavenumber (wavenumber) 1675 ~ 1775 cm ^-1 , preferably wavenumber (wavenumber) ) Peaks may be present at 825-875 cm ⁻¹ and wavenumber 1700-1750 cm ⁻¹ .

[How to measure]

The super water-repellent coating composition was coated on the pretreated treated surface, and heat-treated to form a super-water repellent coating layer, and then the Raman spectrum was measured.

Specifically, Figure 4 is a composition containing 0.5 parts by weight of a zirco aluminate (Al / Zr) -based coupling agent with respect to 100 parts by weight of the main resin as a composition (blue line) and a composition containing no coupling agent As a result of Raman spectra of the sample forming the coating layer (red line), the COC bend can be identified in the region corresponding to the wavenumber of 851 cm ^-1 , and the C = C bend in the region corresponding to the frequency of 1720 cm ^-1 . You can see that (bend) is created.

Through this, it can be seen that a chemical bond is formed through an ester bond between the metal-based coupling agent and the adhered surface, and the substrate and the coupling agent are connected as shown in FIG. 1.

Super water-repellent coating layer according to the present invention is a binder comprising a main resin and a metal-based coupling agent; Conductive fillers; And a coating stabilizer.

On the other hand, the super water-repellent coating layer may be applied to the electromagnetic shielding coating, in this case, the super water-repellent coating layer may have a thickness of 30㎛ or more, preferably 35㎛ or more, more preferably 40㎛ or more. If the thickness of the super water-repellent coating layer is less than 30㎛ electromagnetic shielding performance may be lowered.

In addition, the super water-repellent coating layer may be 450 ~ 750 S / m, preferably 500 ~ 700 S / m, the electrical conductivity when measuring the electrical conductivity through a four point probe (4 point-probe) technique .

Superhydrophobic coating composition according to the present invention comprises the steps of preparing a first solution comprising a conductive filler; Preparing a second solution by mixing a coating stabilizer with the first solution; And preparing a third solution by mixing the second solution with a binder including a metal coupling agent and a main resin.

In the preparing of the first solution, a first solution including a conductive filler may be prepared by a method commonly used in the art, and preferably, by dispersing the conductive filler through ultrasonication equipment. It can manufacture.

On the other hand, before performing the step of preparing the second solution, the step of mixing a dispersant in the first solution; may further comprise a. The description of the dispersant is omitted as it is the same as the description of the dispersant of the superhydrophobic coating composition.

In the preparing of the third solution, a third solution may be prepared by mixing a second solution with a binder including a metal coupling agent and a main resin, prior to adding the metal coupling agent and the main resin into the second solution. As a binder is prepared by mixing a metal coupling agent with the main resin, dispersibility may be further improved.

Super water-repellent coating layer according to the present invention, the step of pre-treating the adhered surface; Coating the superhydrophobic coating composition according to the present invention on the pretreated surface; And heat-treating the superhydrophobic coating composition coated on the adherend surface.

On the other hand, as the pretreatment step and the super water-repellent coating layer forming step is performed, as shown in Figure 10 it can exhibit a significant adhesive force synergistic effect.

First, the step of pretreating the adherend surface will be described.

The pretreatment may be used without limitation as long as the pretreatment method commonly used in the art, and preferably wet or dry etching may be used.

The wet etching removes contaminants on the substrate in order to smoothly form a coating layer on the adhered surface by pretreatment through a cleaning solution such as paragna and acetone.

Dry etching may be performed through plasma equipment, and functional groups may be generated on the surface of the substrate or hydrophilic treatment may be performed as shown in FIG. 9 so that the coating layer is uniformly formed on the surface to be deposited. The functional group may be, for example, -OH, -COOH and -NH _{2 and the} like.

Although the two pretreatment processes may be mixed or used alone, it may be more advantageous to express the desired effect of the present invention. When performing the above-described pretreatment process it can exhibit a change in the contact angle as shown in FIG.

Next, the step of coating the composition for super water-repellent coating will be described.

The coating may be used without limitation as long as it is a coating method commonly used in the art, and may be preferably performed through one of coating methods such as spray, dip, and spin.

Specifically, as shown in FIG. 2, the coating film may be formed on the substrate by one of coating methods such as spray, dip, and spin.

Next, the step of heat-treating the coated super water-repellent coating composition will be described.

The heat treatment can be used without limitation as long as the heat treatment conditions that can be commonly used in the art, preferably is not limited so long as it is a condition that can remove the solvent provided in the super water-repellent coating composition, in the present invention it It is not limited.

Conventionally, the liquid coating method has been used to coat the surface of the inorganic particles with a functional coating film. This liquid coating method has a disadvantage in that it is difficult to form a thin and uniform coating film. However, the present invention, unlike the prior art, by forming a functional group on the surface to be deposited or hydrophilic surface treatment to create an environment in which the coating layer can be uniformly coated in micro units, applying a metal-based coupling agent (coupling agent) to the main resin of the binder By increasing the bonding strength of the main resin to be adhered to the existing adhered surface to improve the durability as well as the effect of increasing the water resistance in the water by using a metal-based coupling agent (coupling agent). In addition, by dispersing a metal coupling agent (coupling agent) in the composition it is possible to form a coating layer in one coating without a separate additional process.

Although the present invention will be described in more detail with reference to the following examples, the following examples are not intended to limit the scope of the present invention, which will be construed as to aid the understanding of the present invention.

< Preparation Substrate Pretreatment Step

First, the substrate was placed in a piranha solution and stirred at 80 ° C. for 1 hour to perform wet etching. In addition, in order to form organic functional groups on the surface of the substrate, a hydrophilic treatment was performed by exposing the substrate for 10 minutes under an atmospheric atmosphere using a UV plasma apparatus.

< Example  1>

First, 0.5 parts by weight of a PDMS resin, which is a hydrophobic polymer resin as the main resin, and a compound satisfying the following Formula 1 with a zirco aluminate (Al / Zr) -based coupling agent based on 100 parts by weight of the main resin, were mixed at 300 rpm. The binder was prepared by stirring for 30 minutes.

In order to prepare the first solution, 15,000 parts by weight of chloroform and 25 parts by weight of multi-walled carbon nanotubes were mixed with a conductive filler based on 100 parts by weight of the main resin, and then, by using an ultrasonic sonication (Ultra sonication) equipment. The first solution was prepared by dispersing for minutes. Then, 0.3 parts by weight of Triton X-100 was added to the first solution as a dispersant based on 100 parts by weight of the main resin and dispersed for 20 minutes by using an ultrasonic sonication equipment. 20 parts by weight of spherical silica (SiO ₂ ) particles having an average particle diameter of 20 nm were mixed with the coating stabilizer based on 100 parts by weight of the main resin in a solution and dispersed for 20 minutes using an ultra sonication equipment. The solution was prepared.

Then, after mixing the binder prepared in the second solution by dispersing for 1 hour using a sonication (Ultra sonication) equipment to prepare a third solution, by dispersing for 10 minutes using an ultrasonic sonication (Ultra sonication) equipment A super water-repellent coating composition was prepared.

Then, the surface of the substrate pre-treated according to the preparation example, a large-area coating composition for the super water-repellent coating was prepared on the substrate by a spray (spray) at a nozzle diameter of 2.5 mm and a spray pressure of 7 bar.

The coated substrate was exposed in a 120 ° C. oven for 2 hours to cure the binder and remove the solvent to form a super water-repellent coating layer having a final average thickness of 40 μm. SEM image of the prepared coating film was as shown in Figure 5, Figure 5a and 5b is a SEM image of the upper coating film, Figure 5c is a SEM image of the coating film inside and Figure 5d is a SEM image of the coating film cross section.

[Formula 1]

At this time, in Formula 1 R ¹ and R ² is a carboxy group (-COOH).

< Example  2 to 6>

Manufactured in the same manner as in Example 1, the content of the metal coupling agent with respect to 100 parts by weight of the main resin was changed from 0.5 parts by weight to 0.3, 1.0, 1.5, 2.0 and 5.0 parts by weight, respectively, to form a super water-repellent coating layer.

< Comparative example  1>

Manufactured in the same manner as in Example 1, the superhydrophobic coating layer was formed by changing the content of the metal coupling agent from 0.5 parts by weight to 0 parts by weight based on 100 parts by weight of the main resin.

< Experimental Example  1: Adhesion Evaluation>

Adhesive evaluation was performed according to ASTM 1002 D for the superhydrophobic coating layer formed through the superhydrophobic coating composition prepared according to Examples 1 to 6 and Comparative Example 1. Five samples for each coupling agent content were prepared and graphed using the average value of the results.

As a result, as shown in FIG. 3, the content of the metal coupling agent optimized for adhesion is 0.5 parts by weight (Example 1), which is 4 times higher than that of Comparative Example 1 without using a metal coupling agent (coupling agent). It can be seen that the increase.

In addition, Examples 1 to 5 can be confirmed that the adhesive strength is superior to Example 6 (including 5 parts by weight of the metal-based coupling agent).

< Comparative example  2>

Prepared in the same manner as in Example 1, to prepare a composition without using a coating stabilizer to form a super water-repellent coating layer.

< Experimental Example  2: Contact angle  And slip angle evaluation>

For the superhydrophobic coating layer formed through the superhydrophobic coating composition prepared according to Example 1 and Comparative Example 2, the contact angle and the sliding angle were evaluated.

As a result, as shown in FIG. 6, the coating surface without using the coating stabilizer was formed to have a contact angle of 150 ° or less to form a super water-repellent surface, and the coating surface using SiO ₂ particles as the coating stabilizer was 150 °. The contact angle mentioned above and the sliding angle of 5 degrees or less were formed. Thus, SiO _2, a coating stabilizer, is essential to form a stable conductive superhydrophobic structure.

< Example  7>

Prepared in the same manner as in Example 1, to form a super water-repellent coating layer so that the thickness of the final super water-repellent coating layer is 20㎛.

< Experimental Example  3: Measurement of electromagnetic shielding rate>

For the superhydrophobic coating layer formed through the superhydrophobic coating composition prepared according to Examples 1 and 7, the electric wave shielding rate was evaluated in the frequency range of 0.5 to 3 GHz.

As a result, it can be seen that when the super water-repellent coating layer according to Example 1 is formed as shown in FIG.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments set forth herein, and those skilled in the art who understand the spirit of the present invention may add components within the scope of the same idea. Other embodiments may be easily proposed by changing, deleting, adding, etc., but this will also fall within the spirit of the present invention.

Claims (10)

A binder comprising a main resin and a metal coupling agent; Conductive fillers; And a coating stabilizer; superhydrophobic coating composition comprising a. The method of claim 1,
The metal coupling agent may be one or more selected from the group consisting of a zirconium (Zr) coupling agent, an aluminum (Al) coupling agent, a zirco aluminate (Al / Zr) coupling agent and a titanium (Ti) coupling agent. Super water-repellent coating composition comprising. The method of claim 2,
The zirco aluminate (Al / Zr) -based coupling agent for a super water-repellent coating composition comprising a compound represented by the following formula (1):
[Formula 1]

In Formula 1, R ¹ and R ² are each independently a straight chain alkyl group of C1 ~ C5, C3 ~ C6 crushed alkyl group, C1 ~ C5 straight alkenyl group, C3 ~ C6 crushed alkenyl group, amino group , A chloro group (-Cl), a carboxy group (-COOH), an epoxy group, a methacrylooxy group, a C1-C5 straight alkoxy group, a C3-C6 crushed alkoxy group, or a C1-C3 alkoxyalkoxy group. . The method of claim 1, wherein the binder,
The super water-repellent coating composition comprising 0.2 to 2.5 parts by weight of the metal-based coupling agent with respect to 100 parts by weight of the main resin. According to claim 1, with respect to 100 parts by weight of the main resin,
3 to 50 parts by weight of a conductive filler including at least one selected from the group consisting of carbon nanotubes, silver (Ag) nanowires, graphene, carbon black, silver (Ag) particles, and carbon fibers,
SiO ₂ , ZrO ₂ , Al ₂ O ₃ , TiO ₂ And 3 to 35 parts by weight of a coating stabilizer comprising at least one selected from the group consisting of carbon black. The method of claim 1,
The composition for a super water-repellent coating further comprises 4,000 to 21,000 parts by weight of a solvent based on 100 parts by weight of the main resin, and 0.05 to 0.8 parts by weight of a dispersant. The method of claim 1,
When measuring Raman spectra by the following measurement method, a composition for a super water-repellent coating having a peak at wavenumber 800 ~ 900 cm ^-1 and wavenumber 1675 ~ 1775 cm ^-1 :
[How to measure]
The super water-repellent coating composition was coated on the pretreated treated surface, and heat-treated to form a super-water repellent coating layer, and then the Raman spectrum was measured. A binder comprising a main resin and a metal coupling agent; Conductive fillers; And a coating stabilizer; superhydrophobic coating layer formed. Preparing a first solution including a conductive filler; Preparing a second solution by mixing a coating stabilizer with the first solution; And preparing a third solution by mixing a binder including a metal coupling agent and a main resin into the second solution. Pretreating the adherend surface; Coating the super water-repellent coating composition according to any one of claims 1 to 7 on the pretreated treated surface; And heat-treating the superhydrophobic coating composition coated on the surface to be adhered.

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