KR20220151277A - Hydrophobic coating layer and manufacturing method of the same - Google Patents

Abstract

The present invention relates to a hydrophobic coating layer and a manufacturing method thereof. The hydrophobic coating layer according to an embodiment of the present invention is formed by applying a composition, which is prepared by dispersing hydrophobically modified silica particles in a solvent having a relative permittivity of 10 to 80, on a predetermined substrate, and includes a smooth layer formed on the substrate and having a first surface roughness and an uneven layer formed on the smooth layer and having a second surface roughness relatively greater than the first surface roughness. According to the other embodiment of the present invention, a manufacturing method of the hydrophobic coating layer comprises the steps of: preparing silica particles; modifying a surface of the silica particles using a hydrophobic silane coupling agent; preparing a composition by dispersing silica particles in a dispersion solvent having a relative permittivity of 10 to 80; preparing a substrate; and applying the composition on the substrate to manufacture a coating layer including a smooth layer having a first surface roughness and an uneven layer formed on the smooth layer and having a second surface roughness greater than the first surface roughness. Accordingly, the coating layer having both excellent hydrophobicity and transparency can be manufactured.

Description

Hydrophobic coating layer and its manufacturing method {HYDROPHOBIC COATING LAYER AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a hydrophobic coating layer and a manufacturing method thereof.

Hydrophobic surface preparation technology is widely used in various industrial fields because it can protect materials from moisture to produce effects such as oxidation, stain prevention, friction resistance reduction, and self-cleaning of materials.

In general, as a method for a hydrophobic surface, a method of lowering surface energy and a method of increasing surface roughness by forming fine irregularities on the surface are known.

It is known to use fluorine-based compounds as one of the methods according to the prior art for lowering the surface energy to produce a hydrophobic surface, but fluorine-based compounds are expensive to use industrially, so they are not economically viable, accumulate in living organisms, and destroy the environment. there was

In addition, methods such as surface lithography technology and vertical alignment of nanotubes/nanofibers are known as conventional methods of increasing surface roughness to produce a hydrophobic surface, but these methods are difficult to manufacture in a large area and costly It is expensive, and the environment and conditions for the process are difficult.

On the other hand, the production of a surface having high transparency while having hydrophobicity is also receiving a lot of attention because it can be applied in various fields such as solar cell panels, lenses and windows.

However, if the surface roughness is increased to produce a surface with higher hydrophobicity, there is a problem of lowering the transparency due to fine irregularities on the surface, and if the surface roughness is lowered to increase the transparency, there is a problem of lowering the hydrophobicity of the surface.

Republic of Korea Patent Registration No. 10-1406116, registered on June 3, 2014 Republic of Korea Patent Publication No. 10-2016-0060913, published on May 31, 2016

An object of the present invention is to solve the above problems, to form a coating layer having high hydrophobicity and excellent transparency at the same time, a dispersion solvent and silica particles dispersed in a dispersion solvent and the surface of which is modified with a hydrophobic silane coupling agent It is to provide a hydrophobic coating layer prepared by applying a composition comprising the same and a method for producing the same.

The object of the present invention is not limited to the object mentioned above, and other objects not mentioned will be clearly understood from the description below.

In order to achieve the above object, the present invention relates to a hydrophobic coating layer and a manufacturing method thereof. In the hydrophobic coating layer according to an embodiment of the present invention, hydrophobically modified silica particles are dispersed in a solvent having a relative dielectric constant of 10 to 80 It is formed by applying the prepared composition on a predetermined substrate, and is formed on the substrate and has a first surface roughness, and a smooth layer formed on the smooth layer and having a second surface roughness relatively greater than the first surface roughness. includes

In order to achieve the above object, a method for preparing a hydrophobic coating layer according to another embodiment of the present invention includes preparing silica particles, modifying the surface of the silica particles using a hydrophobic silane coupling agent, and reducing the dielectric constant of the silica particles. preparing a composition by dispersing in a dispersion solvent of 10 to 80, preparing a substrate, and applying the composition on a substrate to form a smooth layer having a first surface roughness and a first surface roughness greater than the first surface roughness formed on the smooth layer. 2 preparing a coating layer including a concavo-convex layer having surface roughness.

The hydrophobic coating layer according to the embodiment of the present invention and its manufacturing method according to the above configuration can expect the following effects.

As the silica particles whose surfaces are modified as a hydrophobic silane coupling agent are used, a coating layer having both excellent hydrophobicity and transparency can be prepared without using a fluorine-based material.

A smooth layer having a first surface roughness and a concave-convex layer having a second surface roughness relatively larger than the first surface roughness are sequentially formed on a substrate using the composition, so that there is no need for difficult process environments or conditions. It is possible to simply prepare a coating layer having excellent hydrophobicity and high transparency.

1 is a flow chart showing the sequence of a method for manufacturing a hydrophobic coating layer according to another embodiment of the present invention.
2 is a view for explaining a method of manufacturing a hydrophobic coating layer according to another embodiment of the present invention.
Figure 3 is a view showing the analysis results of the average diameter of the agglomerated silica particles according to the reference example.
Figure 4 is a view showing the average diameter analysis results of the agglomerated silica particles according to the reference example.
5A is a view showing the contact angle measurement results according to Test Example 1 of the coating layer prepared according to Example 1.
Figure 5b is a view showing the contact angle measurement results according to Test Example 1 of the coating layer prepared according to Example 3.
5C is a view showing the contact angle measurement results according to Test Example 1 of the coating layer prepared according to Example 5.
5D is a view showing the contact angle measurement results according to Test Example 1 of the coating layer prepared according to Example 6.
6a to 6c are views showing the transmittance measurement results according to Test Example 2.
7a to 7b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Example 1;
8a to 8b are views showing the results of scanning electron microscope analysis according to Test Example 3 of the coating layer prepared according to Example 2;
9a to 9b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Example 3;
10A to 10B are diagrams showing the results of scanning electron microscope analysis according to Test Example 3 of the coating layer prepared according to Example 4;
11a to 11b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Example 9;
12a to 12b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Comparative Example 1;
13a to 13b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Comparative Example 4;
14a to 14b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Comparative Example 5;
15a to 15b are views showing the results of scanning electron microscope analysis according to Test Example 3 of the coating layer prepared according to Comparative Example 6;
16a to 16b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Comparative Example 7;
17a to 17b are diagrams showing scanning electron microscope analysis results according to Test Example 3 of the coating layer prepared according to Example 1;
18a to 18b are diagrams showing the results of scanning electron microscope analysis according to Test Example 3 of the coating layer prepared according to Example 3;

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only the present embodiments make the disclosure of the present invention complete, and those skilled in the art in the art to which the present invention belongs It is provided to fully inform the person of the scope of the invention. Meanwhile, terms used in this specification are for describing embodiments, and are not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase.

A method for manufacturing a hydrophobic coating layer according to another embodiment of the present invention relates to a method for manufacturing a hydrophobic coating layer according to an embodiment of the present invention, and a time-sequential performing step for manufacturing a hydrophobic coating layer according to an embodiment of the present invention. include them

For convenience of explanation, in describing the hydrophobic coating layer and the manufacturing method thereof according to the embodiments of the present invention, substantially the same components are described with the same reference numerals, and repeated descriptions are omitted.

The surface roughness described in the specification of the present invention may mean the degree of unevenness formed on the surface, and may mean at least one of parameters for surface roughness commonly used in the related art, for example, the arithmetic mean It may mean at least one of roughness (R _a ), maximum height roughness (R _max ), and 10-point average roughness (R _z ).

Referring to FIG. 1 , the method for preparing a hydrophobic coating layer according to another embodiment of the present invention includes a particle preparation step (S100), a surface modification step (S200), a composition preparation step (S300), and a coating layer preparation step (S400). .

Referring to FIG. 2 , the hydrophobic coating layer 10 according to an embodiment of the present invention includes a smooth layer 11 and an uneven layer 12 .

First, prepare silica particles (S100).

The diameter of the silica particles prepared in the particle preparation step (S100) may be 1 to 1000 nm, preferably 1 to 400 nm, and more preferably 1 to 5 nm.

If the diameter of the silica particles prepared in the particle preparation step (S100) is less than 1 nm, the size of the silica particles is too small, and the surface roughness of the coating layer prepared in the coating layer preparation step (S400) may be low.

If the diameter of the silica particles prepared in the particle preparation step (S100) exceeds 1000 nm, the diameter of the silica particles is too large and the area where the silica particles contact the substrate 20 when the coating layer 10 is formed in the coating layer preparation step (S400) This separation may reduce the binding force of the silica particles to the substrate 20, and the transparency of the hydrophobic coating layer 10 prepared by the method of manufacturing a hydrophobic coating layer according to another embodiment of the present invention may decrease.

The particle preparation step (S100) may be a step of synthesizing silica particles from a silica precursor by using a sol-gel process. It may be a step of synthesizing particles.

Here, the silica precursor is not limited as long as it is commonly used in the synthesis of silica particles using the sol-gel process, and for example, tetraethoxy silane, methyl trimethoxy silane, and methyl trie It may contain at least one selected from methyl triethoxy silane.

Here, the alcohol may include at least one selected from methanol, ethanol, propanol, and butanol, and may be preferably ethanol.

In addition, here, ammonia water may be mixed in the mixed solution as a base catalyst in the synthesis of silica particles, and the pH value of the mixed solution may be adjusted according to the mixing amount of ammonia water, and the silica particles may be adjusted according to the adjusted pH value. diameter can be varied.

At this time, the pH value of the mixed solution adjusted as ammonia water is mixed may be 10 to 13, and the pH value of the mixed solution is adjusted to 10 to 13, so that the silica particles prepared in the particle preparation step (S100) are 1 to 1000 nm. may have a diameter of

The particle preparation step (S100) may further include purifying the silica particles from the mixed solution when preparing a mixed solution by mixing a silica precursor and alcohol and synthesizing silica particles by mixing ammonia water with the prepared mixed solution, The present invention is not limited thereto, and the silica particles synthesized in the mixed solution may be prepared in a dispersed form without purifying the silica particles from the mixed solution.

When the particle preparation step (S100) further includes a step of purifying the silica particles from the mixed solution, the purification of the silica particles may be performed by separating reaction products from the reaction solution, for example, by using a centrifugal separator. can be used.

The surface of the silica particles prepared in the particle preparation step (S100) is modified using a hydrophobic silane coupling agent (S200).

The hydrophobic silane coupling agent used in the surface modification step (S200) may be for hydrophobically modifying the surface of the silica particles, 3-aminopropyl triethoxysilane, hexadecyltrimethoxysilane ( Hexadecyltrimethoxysilane) and 3-trimethoxysilylpropylmethacrylate (3-Methacryloxypropyl trimethoxysilane).

The surface modification step (S200) may be a step of modifying the surface of the silica particles to be hydrophobic by reacting the silica particles prepared in the particle preparation step (S100) with a hydrophobic silane coupling agent.

The surface modification step (S200) is a step of chemically bonding the hydrophobic silane coupling agent to the silica particles prepared in the particle preparation step (S100) by reacting the silica particles prepared in the particle preparation step (S100) with the hydrophobic silane coupling agent. have.

In the surface modification step (S200), when the silica particles prepared in the particle preparation step (S100) are prepared in a dispersed form in the mixed solution, a hydrophobic silane coupling agent is mixed with the mixed solution to react the silica particles and the hydrophobic silane coupling agent, thereby forming silica It may be a step of modifying the surface of the particle.

At this time, the surface modification step (S200) may further include purifying the surface-modified silica particles from the mixed solution and drying the purified silica particles, and the method of purifying the silica particles from the mixed solution is conventional. As a method, a method of purifying a reaction product from a reaction solution may be used, and for example, a method using a centrifugal separator may be used.

A composition is prepared by dispersing the silica particles obtained in the surface modification step (S200) in a dispersion solvent (S300).

The composition preparation step (S300) may be to prepare a composition by mixing the dispersion solvent and the silica particles obtained in the surface modification step (S200).

The composition prepared in the composition preparation step (S300) may include a dispersion solvent and silica particles dispersed in the dispersion solvent.

When the silica particles are dispersed in the dispersion solvent during the preparation of the composition in the composition preparation step (S300), the silica particles may be aggregated in the dispersion solvent, and the average diameter of the silica particles aggregated in the dispersion solvent may be 100 nm to 5 μm have.

When the average diameter of the aggregated silica particles in the dispersion solvent of the composition prepared in the composition preparation step (S300) is less than 100 nm, the surface roughness of the coating layer 10 prepared in the coating layer preparation step (S400) may be low.

When the average diameter of the agglomerated silica particles in the dispersion solvent of the composition prepared in the composition preparation step (S300) exceeds 5 μm, the specific surface area of the agglomerated silica particles is relatively reduced, thereby forming the coating layer 10 in the coating layer preparation step (S400). When forming, the contact area of the agglomerated silica particles to the substrate 20 is reduced, so that the binding force of the silica particles to the substrate 20 may decrease.

That is, when the average diameter of the agglomerated silica particles in the dispersion solvent of the composition prepared in the composition preparation step (S300) exceeds 5 μm, the agglomerated silica particles are not firmly bonded to the substrate 20 and This may lead to deterioration in coverage and durability of the coating layer 10 .

In addition, when the average diameter of the aggregated silica particles in the dispersion solvent of the composition prepared in the composition preparation step (S300) exceeds 5 μm, the surface roughness of the coating layer 10 prepared in the coating layer preparation step (S400) becomes too large. The transparency of the coating layer 10 to be may fall.

On the other hand, the 'coverage' described in the specification of the present application is applied to the surface of the substrate 20 when the coating layer 10 is prepared by applying the composition to the surface of the substrate 20 in the coating layer manufacturing step (S400). It may mean the ratio at which the coating layer 10 is formed with respect to the designated area.

Preferably, the average diameter of the silica particles aggregated in the dispersion solvent of the composition prepared in the composition preparation step (S300) may be 125 nm to 3.7 μm, 155 nm to 1020 nm, and 165 to 1020 nm. And, it may be 190 to 1017 nm, may be 270 to 1017 nm, may be 307 to 1017 nm, may be 270 to 476 nm, may be 307 to 476 nm.

The degree of aggregation of the silica particles dispersed in the dispersion solvent of the composition prepared in the composition preparation step (S300) may vary depending on the dielectric constant of the dispersion solvent, and the higher the relative dielectric constant of the dispersion solvent, the greater the degree of aggregation of the silica particles. .

That is, as the dielectric constant of the dispersion medium increases, the average diameter of the silica particles agglomerated in the dispersion medium may increase.

In preparing the composition in the composition preparation step (S300), the relative permittivity of the dispersion solvent in which the silica particles are dispersed may be 10 to 80.

If the relative permittivity of the dispersion solvent is less than 10 in the composition preparation step (S300), the degree of aggregation of the silica particles in the dispersion solvent is too low, so that the coating layer 10 is smooth during the preparation of the coating layer 10 in the coating layer preparation step (S400) to be described later. Since it is not formed properly, the surface roughness may be lowered and the hydrophobicity may be lowered.

In the composition preparation step (S300), when the relative permittivity of the dispersion solvent exceeds 80, the silica particles in the dispersion solvent are excessively aggregated, and as the average diameter of the aggregated silica particles becomes too large, the specific surface area decreases, which will be described later in the coating layer preparation step (S400) In the manufacturing of the coating layer 10, the agglomerated silica particles do not sufficiently contact the substrate 20, so they cannot be firmly bonded and may be separated from the substrate 20.

That is, when the relative dielectric constant of the dispersion solvent exceeds 80 in the composition preparation step (S300), the coverage, which is the ratio in which the coating layer 10 is formed with respect to the area where the composition is applied on the surface of the substrate 20, may decrease, The durability of the coating layer 10 may deteriorate.

Preferably, the relative dielectric constant of the dispersion solvent in which the silica particles are dispersed during the preparation of the composition in the composition preparation step (S300) may be 17 to 72, 19 to 60, 20 to 60, and 24 to 60 days. It may be 28 to 60, may be 28 to 48, may be 37 to 48.

The dispersion solvent in which the silica particles are dispersed during the preparation of the composition in the composition preparation step (S300) is not limited as long as it has a dielectric constant of 10 to 80, but at least one selected from ethanol, 1-propanol, 2-propanol, butanol and water may include

Preferably, the dispersion solvent in which the silica particles are dispersed during the preparation of the composition in the composition preparation step (S300) may include ethanol and water.

The composition preparation step (S300) may be to prepare a composition by dispersing more than 0.5 parts by weight and less than 2 parts by weight of the silica particles obtained in the surface modification step (S200) in 100 parts by weight of the dispersing solvent.

That is, the composition preparation step (S300) may be a step of preparing a composition containing 100 parts by weight of the dispersion solvent and more than 0.5 parts by weight and less than 2 parts by weight of the silica particles obtained in the surface modification step (S200).

If the amount of silica particles contained in the composition prepared in the composition preparation step (S300) is 0.5 parts by weight or less, the amount of silica particles coated on the substrate 20 is insufficient when the coating layer 10 is formed in the coating layer preparation step (S400). Since the entire surface of the substrate 20 is not coated, coverage may be reduced.

When the silica particles contained in the composition prepared in the composition preparation step (S300) are 2 parts by weight or more, the amount of silica particles coated on the substrate 20 is excessive when forming the coating layer 10 in the coating layer preparation step (S400). The transparency of the coating layer 10 to be may fall.

A coating layer 10 is prepared by preparing a substrate 20 and applying the composition prepared in the composition preparation step (S300) on the substrate 20 (S400).

In the coating layer preparation step (S400), the coating layer 10 is prepared by applying the composition prepared in the composition preparation step (S300) on the substrate 20 and drying to evaporate the dispersion solvent included in the composition to form the coating layer 10. It may be a step to

That is, when the composition prepared in the composition preparation step (S300) is applied on the substrate 20 in the coating layer preparation step (S400) and dried, the dispersion solvent included in the composition is evaporated and the silica particles dispersed in the dispersion solvent are applied to the substrate 20 ) The coating layer 10 may be prepared by being bonded and coated.

The coating layer preparation step (S400) may be a step of preparing the coating layer 10 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20.

The coating layer preparation step (S400) may be a step of forming the coating layer 10 on the substrate 20 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20.

The coating layer preparation step (S400) may be a step of forming the coating layer 10 having a predetermined surface roughness on the substrate 20 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20.

In the coating layer preparation step (S400), the coating layer 10 having an arithmetic average roughness (R _a ) of 0.1 to 1 μm is applied on the substrate 20 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20. It may be a step of forming.

If the arithmetic mean roughness of the coating layer 10 formed in the coating layer manufacturing step (S400) is less than 0.1 μm, the surface roughness of the coating layer 10 may be too low and the hydrophobicity of the coating layer 10 may deteriorate, and if it exceeds 1 μm, the coating layer ( The surface roughness of 10) is too large, and the transparency of the coating layer 10 may decrease.

Preferably, the coating layer preparation step (S400) is a step of forming the coating layer 10 having an arithmetic mean roughness (R _a ) of 0.12 to 0.93 μm on the substrate 20 by applying the composition prepared in the composition preparation step (S300) , and may be a step of forming the coating layer 10 having an arithmetic mean roughness (R _a ) of 0.12 to 0.9 μm, and forming the coating layer 10 having an arithmetic mean roughness (R _a ) of 0.19 to 0.83 μm. It may be a step of forming the coating layer 10 having an arithmetic mean roughness (R _a ) of 0.2 to 0.8 μm.

The coating layer preparation step (S400) may be a step of forming the coating layer 10 having a contact angle of 120 to 180° on the substrate 20 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20. have.

Preferably, the coating layer preparation step (S400) is to apply the composition prepared in the composition preparation step (S300) to the surface of the substrate 20 to form a coating layer 10 having a contact angle of 125 to 180 ° on the substrate 20 It may be a step of forming the coating layer 10 having a contact angle of 135 to 180 °, and may be a step of forming the coating layer 10 having a contact angle of 137 to 180 °, and a coating layer of 139 to 180 ° ( 10) may be a step of forming.

More preferably, in the coating layer preparation step (S400), the coating layer 10 having a contact angle of 144 to 180 ° is formed on the substrate 20 by applying the composition prepared in the composition preparation step (S300) to the surface of the substrate 20. It may be a step of doing, and may be a step of forming the coating layer 10 having an angle of 150 to 180 °.

When the composition prepared in the composition preparation step (S300) is applied on the substrate 20 in the coating layer preparation step (S400), the temperature of the applied composition may be 25 °C or more and less than 70 °C.

When the composition prepared in the composition preparation step (S300) is coated on the substrate 20 in the coating layer preparation step (S400), when the temperature of the composition to be coated is less than 25 ° C., the rate of evaporation of the dispersion solvent is too slow to perform another embodiment of the present invention. Productivity of the hydrophobic coating layer 10 manufactured according to the manufacturing method of the hydrophobic coating layer according to the example may decrease.

On the other hand, in the coating layer preparation step (S400), the coating layer formed by applying the composition prepared in the composition preparation step (S300) on the substrate 20 and drying to evaporate the dispersion solvent included in the composition to form the coating layer 10 ( A plurality of microcracks may be formed in 10), and surface roughness of the coating layer 10 may increase as the number of interfaces between cracks formed in the coating layer 10 increases.

When the composition prepared in the composition preparation step (S300) is coated on the substrate 20 in the coating layer preparation step (S400), when the temperature of the composition to be coated is 70 ° C. or higher, the rate of evaporation of the dispersion solvent is too fast, so that the coating layer 10 The number of micro-cracks formed may be reduced, and thus, the surface roughness of the coating layer 10 may be lowered, thereby reducing the hydrophobicity of the coating layer 10 .

In the coating layer manufacturing step (S400), the coating layer 10 may be formed by applying a composition on the substrate 20 using a brush having a predetermined roughness.

Here, forming the coating layer 10 by applying the composition on the substrate 20 using a brush may mean forming the coating layer 10 by brushing the composition on the substrate 20 using a brush. .

In the coating layer preparation step (S400), the coating layer 10 is formed by brushing the composition on the substrate 20 with a brush at least once, preferably 1 to 5 times, more preferably 1 to 4 times, and still more preferably 2 times. It may be a step to

The coating layer manufacturing step (S400) may include a substrate preparation step (S410), a smooth layer forming step (S420), and an uneven layer forming step (S430).

The substrate preparation step ( S410 ) may be a step of preparing the substrate 20 .

The substrate 20 prepared in the substrate preparation step (S410) is not limited as long as it is made of a material commonly used in the field requiring a hydrophobic surface, for example, polyethylene terephthalate (Poly Ethylene Terephthalate, PET), glass and at least one selected from among metals.

In the smoothing layer forming step (S420), the composition prepared in the composition manufacturing step (S300) is applied on the substrate 20 prepared in the substrate preparation step (S410) to form a smooth layer 11 having a first surface roughness. may be a step.

In the smoothing layer forming step (S420), the composition prepared in the composition manufacturing step (S300) is applied on the substrate 20 prepared in the substrate preparation step (S410) to form a smoothing layer 11 having a first surface roughness. It may be a step of manufacturing the smoothing layer 11 .

In the smoothing layer forming step (S420), the smoothing layer 11 having a relatively lower surface roughness than the uneven layer 12 formed in the uneven layer forming step (S430) is formed to form the coating layer 10 in the coating layer manufacturing step (S400). It may be a step for uniformly forming the coating layer 10 as a whole on the surface of the substrate 20 to be formed without the portion where the coating layer 10 is not formed.

The smoothing layer forming step ( S420 ) may be a step of forming the smoothing layer 11 by applying a composition on the substrate 20 using the first brush 30 having a first roughness.

Here, forming the smooth layer 11 by applying the composition on the substrate 20 using the first brush 30 means that the composition is brushed on the substrate 20 using the first brush 30 to form the smooth layer. (11) can mean forming.

In the uneven layer forming step (S430), the composition prepared in the composition preparation step (S300) is applied on the smoothing layer 11 formed in the smoothing layer forming step (S420) so that the second surface roughness is relatively greater than the first surface roughness. It may be a step of forming the uneven layer 12 having a.

The uneven layer forming step (S430) is formed in the coating layer manufacturing step (S400) by forming the uneven layer 12 having a relatively larger second surface roughness than the smoothing layer 11 formed in the smoothing layer forming step (S420). It may be a step for increasing surface roughness of the coating layer 10 .

The concavo-convex layer forming step (S430) may be a step of forming the concavo-convex layer 12 by applying a composition on the smooth layer 11 using the second brush 40 having a relatively greater second roughness than the first roughness. have.

Here, forming the uneven layer 12 by applying the composition on the smooth layer 11 using the second brush 40 means brushing the composition using the second brush 40 on the smooth layer 11 It may mean forming the concave-convex layer 12 .

In the uneven layer forming step (S430), the uneven layer 12 is formed on the smooth layer 11 using the second brush 40 having a relatively greater roughness than the first brush 30, thereby manufacturing a coating layer (S400). ) The coating layer 10 formed in may have a greater surface roughness.

That is, the uneven layer 12 is formed in the uneven layer forming step (S430) so that the coating layer 10 has a larger surface roughness, so that the coating layer 10 prepared in the coating layer manufacturing step (S400) can have greater hydrophobicity. have.

On the other hand, the first brush 30 and the second brush 40 are provided on the lower surfaces of the gripping handles 31 and 41 and the gripping handles 31 and 41 that can be gripped by the user, respectively, so that the user can It may include a plurality of brush hairs (32, 42) that the coating liquid touches to brush.

At this time, the object to be coated may be the substrate 20 .

The fact that the second roughness of the second brush 40 is greater than the first roughness of the first brush 30 indicates that the brush hairs 42 of the second brush 40 are the brush hairs of the first brush 30. It may mean that mechanical deformation is difficult to achieve when an external force is applied than (32), and the bristles 42 of the second brush 40 are more rigid than the bristles 32 of the first brush 30 ( stiffness) may mean that the bristles 42 of the second brush 40 have a greater Young's modulus than the bristles 32 of the first brush 30. .

In addition, the fact that the second roughness of the second brush 40 is greater than the first roughness of the first brush 30 means that the area of the lower surface of the gripping handle 41 of the second brush 40 is compared to the brush bristles ( 42) means that the density of brush hairs 42, which is the number of brushes, is smaller than the density of brush hairs 32, which is the number of brush hairs 32 relative to the area of the lower surface of the gripping handle 31 of the first brush 30 it could be

The uneven layer forming step ( S430 ) may be a step of forming the uneven layer 12 having a relatively greater arithmetic mean roughness (R _a ) than the smooth layer 11 formed in the smoothing layer forming step ( S420 ).

That is, the uneven layer 12 formed in the uneven layer forming step ( S430 ) may have a relatively greater arithmetic average roughness (R _a ) than the smooth layer 11 formed in the smooth layer forming step ( S420 ).

The arithmetic mean roughness (R _a ) of the smoothing layer 11 formed in the smoothing layer forming step (S420) may be 0.1 to 0.3 μm.

If the arithmetic average roughness (R _a ) of the smoothing layer 11 formed in the smoothing layer forming step (S420) is less than 0.1 μm, the hydrophobicity of the hydrophobic coating layer 10 prepared according to the embodiment of the present invention may be poor, and 0.3 If it exceeds ㎛, the surface roughness of the smoothing layer 11 is large, and the formation of the concave-convex layer 12 on the smoothing layer 11 may not be performed smoothly.

Preferably, the arithmetic average roughness (R _a ) of the smoothing layer 11 formed in the smoothing layer forming step (S420) may be 0.12 to 0.25 μm, and may be 0.19 to 0.21 μm.

An arithmetic average roughness (R _a ) of the uneven layer 12 formed in the uneven layer forming step ( S430 ) may be 0.6 to 1 μm.

If the arithmetic average roughness (R _a ) of the uneven layer 12 formed in the uneven layer forming step (S430) is less than 0.6 μm, the surface roughness of the uneven layer 12 is too small, resulting in the hydrophobicity produced according to one embodiment of the present invention. The hydrophobicity of the coating layer 10 may be deteriorated, and if the thickness exceeds 1 μm, the surface roughness of the uneven layer 12 may be too large, and thus the transparency of the hydrophobic coating layer 10 prepared according to an embodiment of the present invention may be deteriorated.

Preferably, the arithmetic mean roughness (R _a ) of the uneven layer 12 formed in the uneven layer forming step (S430) may be 0.68 to 0.9 μm, 0.7 to 0.85 μm, or 0.75 to 0.83 μm. .

2, in the smoothing layer forming step (S420), the smoothing layer 11 is formed on the substrate 20 using the first brush 30, and in the uneven layer forming step (S430), the second brush ( 40) to form the uneven layer 12 on the smooth layer 11, thereby forming the hydrophobic coating layer 10 including the smooth layer 11 and the uneven layer 12.

<Example 1>

1. Preparation of silica particles

First, silica precursor, tetraethoxysilane (product name: Tetraethylorthosilicate (TEOS, 98%), manufacturer: Sigma-Aldrich) and alcohol, ethanol (product name: Anhydrous ethyl alcohol (ethanol, 99.9%), manufacturer: Daejeong Chemical Gold) A mixed solution was prepared by mixing, and ammonia water was mixed with the prepared mixed solution to synthesize silica particles.

More specifically, a mixed solution was prepared by mixing 50.02 ml of ethanol and 3 ml of tetraethoxysilane, and ammonia water having a concentration of 0.46 M was mixed with the prepared mixed solution to adjust the pH of the mixed solution to 10.912 to synthesize silica particles. By doing so, silica particles dispersed in the mixed solution were prepared.

2. Surface modification of silica particles

1. 0.51 ml of hexadecyltrimethoxysilane as a hydrophobic silane coupling agent was mixed with the mixed solution obtained in the preparation of silica particles and stirred at 300 rpm for 2 hours. Thereafter, surface-modified silica particles were purified from the mixed solution using a centrifuge, and the purified silica particles were dried at 70° C. for 24 hours.

3. Preparation of the composition

2. A composition was prepared by mixing 1 part by weight of silica particles obtained from surface modification of silica particles with 100 parts by weight of a dispersion solvent. At this time, a mixed solution prepared by mixing 56.2% by volume of ethanol (product name: Anhydrous ethyl alcohol (ethanol, 99.9%), manufacturer: Daejeong Chemical Gold) and 43.8% by volume of water was used as the dispersion solvent.

4. Preparation of the coating layer

A substrate 20 was prepared, and the coating layer 10 was prepared by applying the composition prepared in 3. Preparation of Composition on the substrate 20 . At this time, the substrate 20 used a polyethylene terephthalate film having a thickness of 125 μm, and the temperature of the applied composition was 25° C.

More specifically, the composition prepared in 3. Preparation of the composition is brushed on the substrate 20 with the first brush 30 having the first roughness to form the smooth layer 11, and the first roughness is relatively greater than the first roughness. The coating layer 10 was prepared by brushing the composition prepared in 3. Preparation of the composition with the second brush 40 having the second roughness on the smooth layer 11 to form the uneven layer 12 .

<Example 2>

The coating layer 10 was prepared in the same manner as in Example 1. However, 3. Instead of using a mixture of 56.2% by volume of ethanol and 43.8% by volume of water as a dispersion solvent in the preparation of the composition, a mixture prepared by mixing 92.0% by volume of ethanol and 8.0% by volume of water was used.

<Example 3>

The coating layer 10 was prepared in the same manner as in Example 1. However, 4. In the formation of the coating layer, brushing the composition with the first brush 30 on the substrate 20 to form the smooth layer 11 and brushing the composition with the second brush 40 on the smooth layer 11 Instead of forming the coating layer 10 by forming the uneven layer 12, the coating layer 10 was formed by brushing the composition on the substrate 20 twice with the first brush 30.

<Example 4>

The coating layer 10 was prepared in the same manner as in Example 2. However, 4. In the formation of the coating layer, brushing the composition with the first brush 30 on the substrate 20 to form the smooth layer 11 and brushing the composition with the second brush 40 on the smooth layer 11 Instead of forming the coating layer 10 by forming the concavo-convex layer 12, the coating layer 10 was formed by brushing the composition on the substrate 20 with the first brush 30 twice.

<Example 5>

The coating layer 10 was prepared in the same manner as in Example 1. However, instead of using a polyethylene terephthalate film as the substrate 20 in the formation of the 4 coating layers, a glass substrate 20 having a thickness of 1 mm was used.

<Example 6>

The coating layer 10 was prepared in the same manner as in Example 1. However, instead of using a polyethylene terephthalate film as the substrate 20 in the formation of the 4 coating layers, a metal substrate 20 having a thickness of 300 μm was used.

<Example 7>

The coating layer 10 was prepared in the same manner as in Example 2. However, instead of using a polyethylene terephthalate film as the substrate 20 in the formation of the 4 coating layers, a glass substrate 20 having a thickness of 1 mm was used.

<Example 8>

The coating layer 10 was prepared in the same manner as in Example 2. However, instead of using a polyethylene terephthalate film as the substrate 20 in the formation of the 4 coating layers, a metal substrate 20 having a thickness of 300 μm was used.

<Example 9>

The coating layer 10 was prepared in the same manner as in Example 3. However, in the formation of the fourth coating layer, the temperature of the composition applied during the formation of the coating layer 10 was set to 40°C, not 25°C.

<Comparative Example 1>

The coating layer 10 was prepared in the same manner as in Example 1. However, 3. Instead of using a mixture prepared by mixing 56.2% by volume of ethanol and 43.8% by volume of water as a dispersion solvent in the preparation of the composition, a mixture prepared by mixing 12.5% by volume of ethanol and 87.5% by volume of water was used.

<Comparative Example 2>

The coating layer 10 was prepared in the same manner as in Comparative Example 1. However, 4. Instead of using a polyethylene terephthalate film as the substrate 20 in the formation of the coating layer, a glass substrate 20 having a thickness of 1 mm was used.

<Comparative Example 3>

The coating layer 10 was prepared in the same manner as in Comparative Example 1. However, 4. In the formation of the coating layer, a metal substrate 20 having a thickness of 300 μm was used instead of a polyethylene terephthalate film as the substrate 20 .

<Comparative Example 4>

The coating layer 10 was prepared in the same manner as in Comparative Example 1. However, 4. In the formation of the coating layer, brushing the composition with the first brush 30 on the substrate 20 to form the smooth layer 11 and brushing the composition with the second brush 40 on the smooth layer 11 Instead of forming the coating layer 10 by forming the concavo-convex layer 12, the coating layer 10 was formed by brushing twice with the first brush 30 on the substrate 20.

<Comparative Example 5>

The coating layer 10 was prepared in the same manner as in Example 3. However, 3. Instead of mixing 1 part by weight of silica particles and 100 parts by weight of a dispersion solvent in the preparation of the composition, 0.5 parts by weight of silica particles and 100 parts by weight of a dispersion solvent were mixed.

<Comparative Example 6>

The coating layer 10 was prepared in the same manner as in Example 3. However, 3. Instead of mixing 1 part by weight of silica particles and 100 parts by weight of a dispersion solvent in the preparation of the composition, 2 parts by weight of silica particles and 100 parts by weight of a dispersion solvent were mixed.

<Comparative Example 7>

The coating layer 10 was prepared in the same manner as in Example 3. However, in the formation of the fourth coating layer, the temperature of the composition applied during the formation of the coating layer was set to 70°C instead of 25°C.

Manufacturing conditions of the coating layer 10 according to Examples 1 to 9 and Comparative Examples 1 to 7 are summarized in Table 1 below.

Dispersion solvent volume ratio
(ethanol:water) brush condition board type parts by weight of silica composition temperature
(℃) Example 1 56.2:43.8 S/H PET One 25 Example 2 92.0:8.0 S/H PET One 25 Example 3 56.2:43.8 S/S PET One 25 Example 4 92.0:8.0 S/S PET One 25 Example 5 56.2:43.8 S/H glass One 25 Example 6 56.2:43.8 S/H metal One 25 Example 7 92.0:8.0 S/H glass One 25 Example 8 92.0:8.0 S/H metal One 25 Example 9 56.2:43.8 S/S PET One 40 Comparative Example 1 12.5:87.5 S/H PET One 25 Comparative Example 2 12.5:87.5 S/H glass One 25 Comparative Example 3 12.5:87.5 S/H metal One 25 Comparative Example 4 12.5:87.5 S/S PET One 25 Comparative Example 5 56.2:43.8 S/S PET 0.5 25 Comparative Example 6 56.2:43.8 S/S PET 2 25 Comparative Example 7 56.2:43.8 S/S PET One 70

Here, 'dispersion solvent volume ratio' refers to the volume ratio in which ethanol and water are mixed in the dispersion solvent in which silica particles are dispersed in 3. Preparation of the composition, and 'substrate type' refers to the volume ratio in which the composition is applied in 4. Formation of the coating layer. (20), and 'parts by weight of silica' means parts by weight of silica particles dispersed in 100 parts by weight of the dispersion solvent in 3. Preparation of the composition, and the temperature of the composition is applied in 4. Formation of the coating layer. It means the temperature of the composition.

In addition, 'S/H' in the 'brush condition' is 4. When the coating layer 10 is prepared by applying the composition on the substrate 20 in the manufacture of the coating layer, the smoothing layer 11 is applied with the first brush 30 It means to prepare the coating layer 10 by forming and forming the uneven layer 12 with the second brush 40 on the smooth layer 11, and 'S / S' means the composition on the substrate 20 This means that the coating layer 10 is formed by brushing twice with the first brush 30 .

<Reference example>

In the reference example, in order to analyze the degree of aggregation of the silica particles obtained in Example 1 2. Surface modification of silica particles when dispersed in a predetermined solvent, the silica particles obtained in Example 1 2. Surface modification of silica particles were prepared in a predetermined solvent. The average diameter of the agglomerated silica particles when dispersed in was measured.

At this time, the average diameter of the aggregated silica particles was measured using a dynamic light scattering measuring device (model name: multi-scope, manufactured by K-one), and the average diameter of the particles dispersed in the solvent was measured using the dynamic light scattering measuring device. Since it is obvious to those skilled in the art to which the present invention pertains, a detailed description thereof will be omitted.

In addition, ethanol, 1-propanol, 2-propanol and 1-butanol were used as solvents. In addition, a mixed solution prepared by mixing 92.0% by volume of ethanol and 8.0% by volume of water, a mixed solution prepared by mixing 74.9% by volume of ethanol and 25.1% by volume of water, a mixed solution prepared by mixing 56.2% by volume of ethanol and 43.8% by volume of water, A mixture prepared by mixing 35.5% by volume of ethanol and 64.5% by volume of water, and a mixture prepared by mixing 12.5% by volume of ethanol and 87.5% by volume of water were used.

The average diameter analysis results of the agglomerated silica particles for the types of solvents used are shown in Table 2 and FIGS. 3 and 4 below, and the relative permittivity commonly known for the solvents used is shown in Table 2 below.

solvent used Average diameter of agglomerated silica particles
(nm) relative permittivity 1-propanol 165.38 20.10 2-Propanol 159.04 19.91 1-Butanol 127.45 17.10 ethanol 190.51 24.30 ethanol: water
(92.0:8.0) 270.33 28.61 ethanol:water
(74.9:25.1) 307.74 37.84 ethanol:water
(56.2:43.8) 475.14 47.99 ethanol: water
(35.5:64.5) 1016.58 59.19 ethanol: water
(12.5:87.5) 3625.42 71.62

In Table 2, ethanol:water means a mixed solution prepared by mixing ethanol and water, and the ratio in parentheses means the volume ratio of ethanol and water. For example, in Table 2, ethanol:water (92.0:8.0) means a mixture of 92.0% by volume of ethanol and 8.0% of water.

Referring to Table 2 and FIGS. 3 and 4, it can be seen that the average diameter of the agglomerated silica particles increases as the relative permittivity of the solvent used increases. This is a result confirming that the higher the dielectric constant of the solvent used, the higher the degree of aggregation of the silica particles in the used solvent.

<Test Example 1>

In Test Example 1, in order to measure the hydrophobicity of the coating layer 10 prepared according to Examples 1 to 9 and Comparative Examples 1 to 7, the contact angle was measured using water as a measuring solvent.

In Test Example 1, the contact angle was measured by dropping 8.65 μl of water on the coating layer 10 prepared according to Examples 1 to 9 and Comparative Examples 1 to 7, and then using a contact angle meter (model name: FM-40, manufactured by KRUSS). measured.

In addition, the sliding angle of the coating layer 10 prepared according to Examples 1, 5, and 6 was also measured.

On the other hand, the 'slip angle' may mean an inclination angle at which the liquid starts to flow with respect to the horizontal bottom surface, and the substrate 20 on which the coating layer 10 manufactured according to Examples 1, 5, and 6 is formed It may mean the tilt angle at which the liquid starts to flow when tilted after being placed on a horizontal floor surface.

The contact angle measurement results according to Test Example 1 are summarized in FIGS. 5A to 5D and Table 3 below.

Figure 5a is a view showing the contact angle measurement result of the coating layer prepared according to Example 1, Figure 5b is a view showing the contact angle measurement result of the coating layer prepared according to Example 3, Figure 5c is a view showing the contact angle measurement result of the coating layer prepared according to Example 5 It is a view showing the contact angle measurement result of the coating layer, and FIG. 5d is a view showing the contact angle measurement result of the coating layer prepared according to Example 6.

Contact angle (°) Sliding angle (°) Example 1 152.6 0 Example 2 136.6 X Example 3 131.9 X Example 4 125.2 X Example 5 139.4 <5 Example 6 144.7 <5 Example 7 137.1 X Example 8 135.3 X Example 9 129.2 X Comparative Example 1 83.7 X Comparative Example 2 64.2 X Comparative Example 3 81.3 X Comparative Example 4 114.6 X Comparative Example 5 112.1 X Comparative Example 6 130.0 X Comparative Example 7 116.4 X

Referring to Table 3, it can be seen that the contact angle of the coating layer 10 prepared according to Examples 1 and 2 is higher than that of the coating layer 10 prepared according to Comparative Example 1, which is This result indicates that the hydrophobicity of the coating layer 10 prepared is greater than that of the coating layer 10 prepared according to Comparative Example 1.

This is a result of confirming that the coverage of the coating layer 10 is reduced due to excessive aggregation of the silica particles in the dispersion solvent when the dielectric constant of the dispersion medium in which the silica particles are dispersed is too high.

In addition, the contact angle of the coating layer 10 prepared according to Examples 5 and 7 is greater than the contact angle of the coating layer 10 prepared according to Comparative Example 2, and the contact angle of the coating layer 10 prepared according to Examples 6 and 8 is It is larger than the contact angle of the coating layer 10 prepared according to Comparative Example 3, and it can be confirmed that the contact angle of the coating layer 10 prepared according to Examples 3 and 4 is greater than the contact angle of the coating layer 10 prepared according to Comparative Example 4, These are also the results of confirming that the coverage of the coating layer 10 is degraded due to excessive aggregation of the silica particles in the dispersion solvent when the dielectric constant of the dispersion medium in which the silica particles are dispersed is too high.

It can be seen that the contact angle of the coating layer 10 prepared according to Example 3 is higher than the contact angle of the coating layer 10 prepared according to Comparative Example 5. When the coating layer 10 is formed, the silica particles are not uniformly coated on the entire surface of the substrate 20, so it can be seen that the coverage, which is the rate at which the coating layer 10 is formed on the entire surface of the substrate 20, falls. to be.

On the other hand, it can be seen that the contact angle of the coating layer 10 prepared according to Examples 1 and 2 is higher than that of the coating layer 10 prepared according to Examples 3 and 4, respectively, which indicates that the second surface roughness It is a result of confirming that hydrophobicity is increased when the surface roughness of the coating layer 10 is improved by forming the concave-convex layer 12 having .

It can be seen that the contact angle of the coating layer 10 prepared according to Examples 3 and 9 is higher than the contact angle of the coating layer 10 prepared according to Comparative Example 7, which indicates that when the composition is applied on the substrate 20, the composition When the temperature of is too high, it can be confirmed that the hydrophobicity of the coating layer 10 produced decreases as the number of microcracks formed in the coating layer 10 decreases.

It can be seen that the sliding angle of the coating layer 10 prepared according to Examples 1, 5, and 6 is less than 5 °, which indicates that the hydrophobicity of the coating layer 10 prepared according to Examples 1, 5, and 6 is very excellent. This is a verifiable result. In particular, the coating layer 10 prepared according to Example 1 has a contact angle of 152.6° and a sliding angle of 0°, indicating that it has superhydrophobicity.

<Test Example 2>

Test Example 2 is an experiment for measuring the transparency of the coating layer 10 prepared according to Examples 1 to 4 and 9 and the coating layer 10 prepared according to Comparative Examples 1, 4 to 7.

In Test Example 2, the substrate 20 having the coating layer 10 prepared according to Examples 1 to 4 and 9 and the substrate 20 having the coating layer 10 prepared according to Comparative Examples 1, 4 to 7 to measure transparency ( 20) was measured.

In Test Example 2, transmittance was measured using a UV-Vis spectrophotometer (model name: Optizen pop, manufactured by Mecasys) in a wavelength range of 300 to 800 nm.

The test results are shown in Figures 6a to 6c and Table 4.

Permeability (%) Example 1 81.69 Example 2 90.30 Example 3 82.02 Example 4 89.75 Example 9 83.14 Comparative Example 1 90.04 Comparative Example 4 85.88 Comparative Example 5 88.01 Comparative Example 6 62.56 Comparative Example 7 86.14

Referring to Table 4, it can be confirmed that the transmittance of the coating layer 10 prepared according to Examples 1 to 4 and 9 exceeds 80%, which indicates that the transmittance of the coating layer 10 prepared according to the embodiment of the present invention This is a result of confirming that the transmittance is not significantly reduced even when the coating layer 10 is formed on the substrate 20 according to the embodiment of the present invention because the transparency is excellent.

Referring to Table 4, the coating layer 10 prepared according to Comparative Example 6 is different from the coating layer 10 prepared according to Examples 1 to 4 and 9 and the coating layer 10 prepared according to Comparative Examples 1, 4, 5 and 7. It can be seen that the transmittance of ) is the lowest, which is a result of confirming that the transparency of the prepared coating layer 10 is reduced when the content of the silica particles dispersed in the dispersion solvent is too high.

<Test Example 3>

Test Example 3 is an experiment for analyzing the surface of the coating layer 10 according to Examples 1 to 4 and 9 and the coating layer 10 according to Comparative Examples 1, 4, 5 and 7.

In Test Example 3, in order to analyze the surface of the coating layer 10 according to Examples 1 to 4 and 9 and the coating layer 10 according to Comparative Examples 1, 4, 5 and 7, the coating layer according to Examples 1 to 4 and 9 ( 10) and the coating layers 10 according to Comparative Examples 1, 4, 5 and 7 were analyzed with a scanning electron microscope.

The analysis results are shown in Figs. 18b.

7A to 7B are diagrams showing scanning electron microscope analysis results according to Test Example 3 according to Example 1, and FIGS. 8A to 8B are views showing scanning electron microscope analysis results according to Test Example 3 according to Example 2, 9A to 9B are diagrams showing scanning electron microscope analysis results according to Test Example 3 according to Example 3, and FIGS. 10A to 10B are views showing scanning electron microscope analysis results according to Test Example 3 according to Example 4, 11a to 11b are views showing scanning electron microscope analysis results according to Test Example 3 according to Example 9, and FIGS. 12a to 12b are views showing scanning electron microscope analysis results according to Test Example 3 according to Comparative Example 1, 13A to 13B are diagrams showing scanning electron microscope analysis results according to Test Example 3 according to Comparative Example 4, and FIGS. 14A to 14B are diagrams showing scanning electron microscope analysis results according to Test Example 3 according to Comparative Example 5, 15A to 15B are diagrams showing scanning electron microscope analysis results according to Test Example 3 according to Comparative Example 6, and FIGS. 16A to 16B are views showing scanning electron microscope analysis results according to Test Example 3 according to Comparative Example 7, 17a to 17b are views showing scanning electron microscope analysis results according to Test Example 3 according to Example 1, and FIGS. 18a to 18b are views showing scanning electron microscope analysis results according to Test Example 3 according to Example 3.

First, referring to FIGS. 7a to 7b, 8a to 8b, and 12a to 12b, looking at the coating layer 10 prepared according to Examples 1 and 2 and the coating layer 10 prepared according to Comparative Example 1, Examples 1 and 2 While it can be seen that the coating layer 10 prepared according to Comparative Example 1 is formed uniformly on the entire surface of the substrate 20, the coating layer 10 prepared according to Comparative Example 1 is somewhat uniformly formed on the substrate 20 It can be seen that the coverage is somewhat lowered because the silica particles are dispersed. If the dielectric constant of the dispersion solvent in which the silica particles are dispersed is too high, the silica particles are excessively agglomerated, resulting in a decrease in the bonding strength between the agglomerated silica particles and the substrate 20, thereby reducing the bonding state. It is a result of confirming that the coverage is lowered due to separation of the agglomerated silica particles from the substrate 20 without being maintained.

9a to 9b, 10a to 10b, and 13a to 13b, looking at the coating layer 10 prepared according to Examples 3 and 4 and the coating layer 10 prepared according to Comparative Example 4, according to Examples 3 and 4 While it can be confirmed that the coating layer 10 prepared is uniformly formed on the entire surface of the substrate 20, the coating layer 10 prepared according to Comparative Example 4 is somewhat not uniformly formed on the substrate 20. It can be seen that the coverage is somewhat lowered. This is because if the dielectric constant of the dispersion solvent in which the silica particles are dispersed is too high, the silica particles are excessively agglomerated, and the bonding force between the agglomerated silica particles and the substrate 20 is lowered and the bonding state is not maintained. As a result, it can be confirmed that the coverage is lowered as the silica particles that have not been aggregated are separated from the substrate 20 .

9a to 9b, 11a to 11b, and 16a to 16b, looking at the coating layer 10 prepared according to Examples 3 and 9 and the coating layer 10 prepared according to Comparative Example 7, prepared according to Examples 3 and 9 It can be seen that the number of microcracks formed in the coating layer 10 prepared according to Comparative Example 7 is slightly smaller than the number of microcracks formed in the coating layer 10 to be formed. This is because when the coating layer 10 is formed by applying the composition on the substrate 20, if the temperature of the composition to be coated is too high, the dispersion solvent evaporates too quickly, and it can be seen that the number of microcracks formed in the coating layer 10 is reduced. This is the result.

Looking at the coating layer 10 prepared according to Example 3 and the coating layer 10 prepared according to Comparative Example 5 with reference to FIGS. 9A to 9B and 14A to 14B, the hydrophobic coating layer 10 prepared according to Example 3 is a substrate (20) While it can be confirmed that the entire surface is uniformly formed, the coating layer 10 prepared according to Comparative Example 5 is not uniformly formed on the substrate 20, so the coverage is somewhat lowered. It can be confirmed that, when the content of the silica particles dispersed in the dispersion solvent decreases, the coverage, which is the ratio in which the coating layer 10 is formed with respect to the area where the composition is applied on the surface of the substrate 20, can fall This is the result.

Looking at the coating layer 10 prepared according to Example 1 and the coating layer 10 prepared according to Example 3 with reference to FIGS. 17A to 17B and 18A to 18B, the coating layer 10 prepared according to Example 1 is It can be seen that more irregularities are formed than the coating layer 10 prepared according to Example 3.

This is done by forming the smooth layer 11 on the substrate 20 using the first brush 30 and forming the uneven layer 12 on the smooth layer 11 using the second brush 40, thereby forming a coating layer ( 10) is a result confirming that the coating layer 10 having a higher surface roughness than when the coating layer 10 is manufactured using the first brush 30 can be manufactured.

<Test Example 4>

In Test Example 4, the surface roughness of the coating layer 10 prepared according to Examples 1 and 3 was measured.

In Test Example 4, the surface roughness was measured by measuring the arithmetic average roughness (R _a ) of the coating layer 10 prepared according to Examples 1 and 3 using a surface profiler (product name: D-300, manufacturer: KLA). -Tencor) was measured three times.

The measurement results are shown in Table 5 below.

Arithmetic mean roughness (㎛) Example 1 1 time 0.798 Episode 2 0.826 3rd time 0.799 Average 0.808 Example 3 1 time 0.195 Episode 2 0.200 3rd time 0.204 Average 0.200

Referring to Table 5, it can be seen that the arithmetic mean roughness of the coating layer 10 prepared according to Example 1 is greater than that of the coating layer 10 prepared according to Example 3. When preparing the coating layer 10 by applying the composition on the substrate 20 during the preparation of the coating layer 10, the smooth layer 11 is formed with the first brush 30 and the second brush is formed on the smooth layer 11. When the uneven layer 12 is formed with the brush 40, the coating layer 10 having a larger surface roughness than the case where the coating layer 10 is formed by brushing the composition on the substrate 20 twice with the first brush 30. ) is a result that can confirm that it can be manufactured.

Those skilled in the art to which the present invention pertains will understand that the present invention can be embodied in other specific forms without changing its technical spirit or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. The scope of the present invention is indicated by the claims to be described later rather than the detailed description above, and all changes or modifications derived from the scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention.

10: coating layer, 11: smooth layer, 12, uneven layer,
20: substrate,
30: first brush, 31: gripping handle, 32: brush hair,
40: second brush, 41, gripping handle, 42: brush head,
S100: particle preparation step,
S200: surface modification step,
S300: composition preparation step,
S400: coating layer manufacturing step,
S410: substrate preparation step, S420: smooth layer forming step, S430: uneven layer forming step.

Claims (9)

preparing silica particles;
modifying the surface of the silica particles using a hydrophobic silane coupling agent;
preparing a composition by dispersing the silica particles in a dispersion solvent having a dielectric constant of 10 to 80;
Preparing a substrate; and
Applying the composition on the substrate to prepare a coating layer including a smooth layer having a first surface roughness and an uneven layer formed on the smooth layer and having a second surface roughness greater than the first surface roughness; to do
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein preparing the coating layer
Preparing the coating layer having an arithmetic mean roughness of 0.1 to 1 μm and a contact angle of 120 to 180 °;
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein preparing the coating layer
Preparing the substrate;
forming the smooth layer having a relatively lower arithmetic mean roughness than the uneven layer by applying the composition on the substrate using a first brush having a first roughness; and
Forming the concavo-convex layer having a relatively greater arithmetic mean roughness than the smooth layer by applying the composition on the smooth layer using a second brush having a second roughness relatively greater than the first roughness; thing
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein preparing the composition
Preparing the composition by dispersing more than 0.5 parts by weight and less than 2 parts by weight of the silica particles in 100 parts by weight of the dispersion solvent
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein forming the coating layer
Forming the coating layer by applying the composition having a temperature of 25 ° C. or more and less than 70 ° C. on the substrate
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein preparing the silica particles
Preparing the silica particles having a particle diameter of 1 to 400 nm
Method for producing a phosphorus hydrophobic coating layer. The method of claim 1, wherein the step of modifying the surface
A step of surface-modifying the silica particles using the silane coupling agent containing at least one selected from 3-aminopropyltriethoxysilane, hexadecyltrimethoxysilane and 3-trimethoxysilylpropylmethacrylate thing
Method for producing a phosphorus hydrophobic coating layer. It is formed by applying a composition prepared by dispersing hydrophobically modified silica particles in a solvent having a relative dielectric constant of 10 to 80 on a predetermined substrate,
A smooth layer formed on the substrate and having a first surface roughness, and a concave-convex layer formed on the smooth layer and having a second surface roughness relatively greater than the first surface roughness
phosphorus hydrophobic coating layer. According to claim 8,
Having an arithmetic mean roughness of 0.1 to 1 μm and a contact angle of 120 to 180 °
phosphorus hydrophobic coating layer.

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