KR102196188B1 - Nano-Coating Composition And Nano-Coating Method Using The Same - Google Patents

Abstract

The present invention relates to a nano-coating composition for a substrate and a coating method using the same, and more particularly, to a nano-coating composition for a substrate capable of uniformly coating on a substrate and a coating method using the same.

Description

Nano-Coating Composition And Nano-Coating Method Using The Same}

The present invention relates to a nano-coating composition for a substrate and a coating method using the same, and more particularly, to a nano-coating composition for a substrate capable of uniformly coating on a substrate and a coating method using the same.

Colloids (or suspensions) of nanoparticles are a material that has been intensively studied as a building block required for self-assembly. Its size can vary from a few nanometers up to a micron. Self-assembly of nano-sized spherical particulates into tightly packed two-dimensional (2D) arrays can produce 2D photonic crystals. When applying such 2D photonic crystals, surface plasmon devices with absorbing or reflecting characteristics of specific wavelengths, biomimetic devices, chemical and biological sensing, light harvesting and environmental purification, etc., from optoelectronics to surface engineering. Since it can be widely applied to a wide range of fields, it plays an important role in the field of nanotechnology.

Various technologies have been developed over the years to achieve the self-assembly technology of nanoparticle colloids, and these methods have been developed differently depending on the area range and properties of the self-assembly, and the complexity of the process. An appropriate method can be selected depending on the ambient conditions (eg temperature or humidity) that affect the formation of the nanoparticle monolayer, which is a very important task for nanotechnologists. Among the several methods, the simplest and most widely studied method is the spin coating method: a colloidal suspension of nanoparticles is dropped onto the substrate, and the substrate is rotated at a constant rotational speed so that the suspension spreads on the substrate, thereby 2D nanoparticles As a method of fabricating in an array, the spin coating method is simple, fast, and suitable for self-assembly of large-area nanoparticles. The use of a non-volatile solvent makes it easier to manufacture, but there is a possibility that an array of nanoparticles that are not generally dense is produced. To prevent this major defect, the coating protocol must be carefully adjusted. For example, some parameters (e.g. particle size distribution and concentration, dispersant viscosity and volatility, spinning speed and acceleration rate) may be adjusted, but it is not easy to find optimal conditions. As another alternative to this, the occurrence of defects may be prevented by further introducing a surfactant into the suspension.

Non-Patent Document 1 describes a surfactant (polyethylene glycol tert-octylphenyl ether, Polyethylene glycol tert-octylphenyl ether, Triton X-100) for coating polystyrene nanoparticles, but it is not sufficient to obtain a uniform coating film. Moreover, Triton X-100 surfactant, which is commonly used in the past, has a disadvantage of being dangerous and difficult to widely use as a material with very strong aqueous toxicity.

(Non-Patent Document 1) Nanotechnology 20 (2009) 025604(8pp) Tunable 3D and 2D polystyrene nanoparticle assemblies using surface wettability, low volume fraction and surfactant effects

The matters described in the background art are provided to help understanding the background of the invention, and may include matters other than the prior art already known to those of ordinary skill in the field to which this technology belongs.

The present invention is to solve the above-described problems, and the present invention is to provide a nano-coating composition for a substrate capable of uniformly coating on a substrate and a coating method using the same.

The present invention provides a nano-coating composition for a substrate containing a solvent, monodisperse spherical fine particles having a nano size, and a surfactant.

According to another example of the present invention, the fine particles are polystyrene, poly (methyl methacrylate) (Poly (methyl methacrylate)), ZnO, TiO ₂ , silica (silica); any one or a mixture of two or more selected from I can.

According to another example of the present invention, the nano size may have a diameter of 1 nm to 2000 nm.

According to another example of the present invention, the solvent is pure; Methanol, ethanol, isopropyl alcohol, 1-methoxy-2-propanol, 1-butanol, 2-butanol, pentanol, octanol, tetrahydrofurfuryl alcohol, cyclohexanol; Methylethyl ether, diethyl ether, ethylpropyl ether; Ethyl acetate, propylene glycol, monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate; Ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, glycol ether, glycol ether acetate; Propylene carbonate; glycerin; Acetonitrile, tetrahydrofuran, dimethyl formamide, N-methyl formamide, dimethyl sulfoxide, 2-propanol; may be any one or a mixture of two or more selected from.

According to another example of the present invention, the surfactant may be a compound represented by Formula 1 below.

[Formula 1]

(Wherein, in Formula 1, R ¹ is an alkyl group having 10 to 20 carbon atoms, and one or two or more -CH ₂ -s present in the alkyl group are each independently CH=CH-, -C≡C-, -O -, -S-, -CO-, -CO-O-, -O-CO-, -OCF ₂ -or -CF ₂ O- may be substituted, and Z has two linking groups)

Further, in Formula 1, R ¹ may be an alkyl group having 10 to 15 carbon atoms.

According to another example of the present invention, Z in Formula 1 may be any one of the following (a) to (e).

(In the above (a) to (e), m is 3 to 20)

According to another example of the present invention, it may be coated on any one substrate selected from glass, silicon wafer, plastic, ceramic, and metal.

The present invention is a first step of mixing a nano-sized monodisperse spherical fine particles and a surfactant in a solvent; A second step of dropping and rotating the coating composition prepared in the first step onto a substrate to spin coating; And a third step of evaporating a solvent by drying the spin-coated thin film in the second step.

According to another example of the present invention, the fine particles may be a coating method of polystyrene.

According to another example of the present invention, the nano-size may be a coating method having a diameter of 1 nm to 2000 nm.

According to another example of the present invention, the step 1-1 of mixing the spherical fine particles having a nano-sized monodisperse spherical particles and a surfactant in a solvent in the first step in a first solvent; A 1-2 step of mixing a surfactant in a second solvent; It may be a coating method comprising the step 1-3 of mixing the mixture obtained in the step 1-1 and the mixture obtained in the step 1-2.

According to another example of the present invention, the surfactant may be a coating method of a compound represented by the following formula (1).

[Formula 1]

(Wherein, in Formula 1, R ¹ is an alkyl group having 10 to 20 carbon atoms, and one or two or more -CH ₂ -s present in the alkyl group are each independently CH=CH-, -C≡C-, -O -, -S-, -CO-, -CO-O-, -O-CO-, -OCF ₂ -or -CF ₂ O- may be substituted, and Z has two linking groups)

According to another example of the present invention, Z in Formula 1 may be a coating method in any one of the following (a) to (e).

(In the above (a) to (e), m is 3 to 20)

According to another example of the present invention, the spin coating in the second step may be a method of coating on any one substrate selected from glass, silicon wafer, plastic, ceramic, and metal.

By using a coating composition containing a specific surfactant on a substrate such as glass, silicon wafer, plastic, ceramic, or metal, a thin film having a uniform coating surface can be obtained. Further, there is an advantage in that a monolayer is formed on the coated thin film, and a thin film having almost no areas in which defects such as voids and multilayers are formed can be obtained.

1 is a 3D optical micrograph according to an embodiment of the present invention.
2 is a 3D optical micrograph according to a reference example of the present invention.
3 is a 3D optical micrograph according to a comparative example of the present invention.

It is apparent to those of ordinary skill in the art that the present invention is not limited to the contents described below, and can be variously modified and modified without departing from the spirit and scope of the present invention. Therefore, such modifications or variations will have to belong to the claims of the present invention, and the scope of the present invention should be interpreted based on the appended claims.

Nano coating composition for substrate

The nano-coating composition for a substrate of the present invention may contain a solvent, monodisperse spherical fine particles having a nano size, and a surfactant.

Monodisperse spherical fine particles having a nano size have a large specific surface area, and depending on the manufacturing method, it is possible to control the surface shape and impart heat resistance properties, as well as to control the optical properties by controlling the particle size. For example, the monodisperse spherical fine particles having a nano size may be nanospheres. In particular, when monodisperse nanoparticles are used as a coating film, there is an advantage of implementing various optical properties through control of light transmission and refractive index when applied to an optical material.

As monodisperse spherical fine particles having a nano-sized, preferably, polystyrene nanospheres such as the following Chemical Formula 3 may be used. Polystyrene nanospheres have a linear structure that allows weak interactions between molecules. In particular, polystyrene nanospheres have excellent transparency, impact resistance and processability. In addition, in addition to polystyrene nanospheres, poly(methyl methacrylate) nanospheres, ZnO nanoparticles, TiO ₂ nanoparticles, or silica nanospheres; any one or two or more selected from A mixture may be used, but is not limited thereto.

[Formula 2]

The nano-size of the monodisperse spherical fine particles may preferably have a diameter of 1 nm to 2000 nm, but 200 to 700 nm may be more preferably used, and 300 to 600 nm may be most preferably used.

The solvent is pure; Methanol, ethanol, isopropyl alcohol, 1-methoxy-2-propanol, 1-butanol, 2-butanol, pentanol, octanol, tetrahydrofurfuryl alcohol, cyclohexanol; Methylethyl ether, diethyl ether, ethylpropyl ether; Ethyl acetate, propylene glycol, monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate; Ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, glycol ether, glycol ether acetate; Propylene carbonate; glycerin; Acetonitrile, tetrahydrofuran, dimethyl formamide, N-methyl formamide, dimethyl sulfoxide, 2-propanol; any one or a mixture of two or more selected from, but is not limited thereto.

As the surfactant, a compound represented by the following formula (1) may be used.

[Formula 1]

In Formula 1, R ¹ is an alkyl group having 10 to 20 carbon atoms, and one or two or more -CH ₂ -s present in the alkyl group are each independently -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -OCF ₂ -or -CF ₂ O- may be substituted, and Z may have two linking groups. In particular, R ¹ in Formula 1 may preferably be used with an unsubstituted alkyl group having 10 to 15 carbon atoms.

Z of Formula 1 may be used in any one of the following (a) to (e).

In the above (a) to (e), m may be 3 to 20, but preferably m may be 8 to 13.

As the compound represented by Formula 1, the following Formula 2 may be preferably used.

[Formula 2]

In Formula 2, m is 3 to 20, and k may be 10 to 15.

By using the compound represented by Formula 1 or Formula 2, the hydroxy group of the compound represented by Formula 1 or Formula 2 has hydrophilicity, and a long chain of an alkyl group having 10 to 20 carbon atoms plays a role of hydrophobicity, thus having a nano size. Since the interaction between the monodisperse spherical particles is made flexible, and the spreadability between the monodisperse spherical particles having a nano size and the substrate is improved, a uniform monolayer thin film with less voids can be obtained.

The coating composition may use 90 to 99 vol% of a solvent, 0.01 to 9 vol% of spherical fine particles, and 0.05 to 3 vol% of a surfactant. Using less than 0.05 vol% of surfactant is not good because the concentration of surfactant is low and uniform single layer formation is not achieved. If it is used in excess of 3 vol%, the viscosity of the coating composition increases rapidly and the coating ability of the composition decreases. So it is not good.

As the substrate, it may be coated on any one substrate selected from glass, silicon wafer, plastic, ceramic and metal, and more preferably, it may be used for glass or silicon wafer for lenses.

Substrate coating method

The coating method of the nano-coating composition for a substrate of the present invention comprises: a first step of mixing monodisperse spherical particles having a nano size and a surfactant in a solvent; A second step of dropping and rotating the coating composition prepared in the first step onto a substrate to spin coating; And a third step of evaporating the solvent by drying the spin-coated thin film in the second step.

As monodisperse spherical fine particles having a nano size, it may be coated using preferably polystyrene nanospheres such as the following formula (3). Polystyrene nanospheres have a linear structure that allows weak interactions between molecules. In particular, polystyrene nanospheres have excellent transparency, impact resistance and processability.

[Formula 2]

The nano-size of monodisperse spherical fine particles may be coated using preferably 1 nm to 2000 nm in diameter, but more preferably 200 to 700 nm may be used for coating, and 300 to 600 nm may be most preferably used for coating. I can.

The solvent is pure; Methanol, ethanol, isopropyl alcohol, 1-methoxy-2-propanol, 1-butanol, 2-butanol, pentanol, octanol, tetrahydrofurfuryl alcohol, cyclohexanol; Methylethyl ether, diethyl ether, ethylpropyl ether; Ethyl acetate, propylene glycol, monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate; Ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, glycol ether, glycol ether acetate; Propylene carbonate; glycerin; Acetonitrile, tetrahydrofuran, dimethyl formamide, N-methyl formamide, dimethyl sulfoxide, 2-propanol; may be coated using any one or a mixture of two or more selected from, but is not limited thereto.

Surfactant may be coated using a compound represented by the following formula (1).

[Formula 1]

In Formula 1, R ¹ is an alkyl group having 10 to 20 carbon atoms, and one or two or more -CH ₂ -s present in the alkyl group are each independently -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -OCF ₂ -or -CF ₂ O- may be substituted, and Z may have two linking groups. In particular, R ¹ in Formula 1 may preferably be used with an unsubstituted alkyl group having 10 to 15 carbon atoms.

Z of Formula 1 may be used in any one of the following (a) to (e).

In the above (a) to (e), m may be 3 to 20, but preferably m may be 8 to 13.

As the compound represented by Chemical Formula 1, the following Chemical Formula 2 may be preferably used for coating.

[Formula 2]

In Formula 2, m is 3 to 20, and k may be 10 to 15.

By using the compound represented by Formula 1 or Formula 2, the hydroxy group of the compound represented by Formula 1 or Formula 2 has hydrophilicity, and a long chain of an alkyl group having 10 to 20 carbon atoms plays a role of hydrophobicity, thus having a nano size. The interaction between the monodisperse spherical particles is made flexible, and the spreadability between the monodisperse spherical particles having a nano size and the substrate is improved, so that a uniform monolayer thin film with less occurrence of voids can be coated.

The coating step of the present invention comprises: a 1-1 step of mixing the spherical microparticles obtained by mixing the monodisperse spherical microparticles and surfactants having a nano-sized in a solvent in the first step in a first solvent; A 1-2 step of mixing a surfactant in a second solvent; A 1-3 step of mixing the mixture obtained in step 1-1 and the mixture obtained in step 1-2 may be additionally included. As described above, the spherical fine particles and the surfactant can be dissolved in a solvent and mixed to accurately control the concentration.

As the substrate, it may be coated on any one substrate selected from glass, silicon wafer, plastic, ceramic, and metal, and more preferably coated on glass or silicon wafer for lenses.

(Example)

Preparation of coating composition

Example 1

The coating composition is a surfactant polyoxyethylene (12) tridecyl ether (PTE, C ₁₃ H ₂₇ (OCH ₂ CH ₂ ) _n OH, n = 12, Sigma-Aldrich) of the following formula ( ₂ ) 1: 400 weight / molar concentration After pre-dissolving in methanol, polystyrene nano-spherical microparticles aqueous suspension (diameter 370 nm, Polysciences, Inc. 2.5% wt / v) was diluted by adding at a ratio of 3: 4 v / v, and before use, the mixed suspension was By sonicating for 5 hours, a suspension of polystyrene nano spherical particles was prepared.

[Formula 2]

(Where m is 12, k is 13)

Reference Example 1

As a coating composition, a coating composition was prepared under the same conditions as in Example 1, except that the surfactant polyoxyethylene (12) tridecyl ether of Formula 2 was excluded from the coating composition of Example 1.

Comparative Example 1

The coating composition is a surfactant of the following formula 3 polyethylene glycol tert-octylphenyl ether (Polyethylene glycol tert-octylphenyl ether, Triton X-100, C ₁₄ H ₂₂ O (C ₂ H _4O ) _n , n = 9-10, Sigma- Aldrich) was pre-dissolved in methanol of 1:400 wt/molar concentration, and then added to an aqueous suspension of polystyrene nano-spherical fine particles (diameter 370 nm, Polysciences, Inc. 2.5% wt/v) at a ratio of 3: 4 v/v. It was diluted, and before use, the mixed suspension was sonicated for 5 hours to prepare a polystyrene nano spherical fine particle suspension.

[Formula 3]

(Where n=9-10)

Substrate coating evaluation experiment

The coating compositions of Example 1, Reference Example 1, and Comparative Example 1 were spin-coated on a glass substrate under the following coating experimental conditions.

First, a 2 Х 2 cm ² rectangular surface polished n-type Si (100) substrate having a 300 nm-thick SiO 2 layer used as a substrate was prepared with acetone, ethanol and deionized (DI) water for 20 minutes, 20 minutes, and After treatment for 10 minutes, the substrate was dried. Next, to form a hydrophilic Si surface, the substrate wafer was treated with an oxidizing agent solution containing a mixture of H ₂ SO ₄ (97%) and H ₂ O ₂ (35%) (4:1 volume ratio) for 1 hour. Then, it was washed with deionized (DI) water and dried.

After the Si substrate treatment, the coating compositions of Example 1, Reference Example 1, and Comparative Example 1 were spin-coated on the substrate, respectively, to prepare a single layer of polystyrene nano-spherical fine particles. The volume of the coating composition was varied according to the size of the substrate, and 200 μl suspension was applied in the case of a 2 Х 2 cm ² Si substrate mounted on a spin coater. Spin coating uses a three-step spin coating process to form a single layer of polystyrene nanoparticles: the first step is the rotation speed is set for 500 rpm 25 seconds, the second step is set to 700 rpm 65 seconds, and the third The step was 25 seconds at 1200rpm speed.

The layer of the prepared polystyrene nanospheres was observed with a field emission scanning electron microscope (SEM, model JSM-6700F, JEOL Co.) and a non-contact 3D optical surface profiler (NV-2400, Nanosystem Co.). Pictures (1.37 mm X 1.03 mm) of the 3D optical microscope observation results measured in Example 1, Reference Example 1, and Comparative Example 1 are shown in FIGS. 1, 2, and 3.

First, when comparing the 3D optical micrographs of Example 1 of the present invention and Comparative Example 1 (Figs. 1 and 2), Reference Example 1 to which the polyoxyethylene (12) tridecyl ether surfactant of the present invention is not added is mostly It can be seen that a non-uniform thin film including voids and multiple layers is formed, whereas Example 1 to which a surfactant of the present invention is added forms a single layer of very uniform polystyrene nano-spherical fine particles. From this, it is clear that the surfactant introduced in the present invention plays an important role in forming a single layer of uniform polystyrene nano-spherical fine particles.

In addition, when comparing the 3D optical micrographs of Example 1 of the present invention and Comparative Example 1 (Figs. 1 and 3), instead of the polyoxyethylene (12) tridecyl ether surfactant of the present invention, the conventional Triton X-100 Comparative Example 1 prepared by adding a surfactant formed a relatively uniform single layer compared to Reference Example 1, but compared to Example 1 to which a surfactant of the present invention was added, there were many voids and multiple layers. It can be seen that it is formed.

Therefore, by introducing the surfactant of the present invention, it is possible to obtain a thin film of excellent polystyrene nano-spherical fine particles with more uniform, high-density packing, and furthermore, a single layer is formed on the coated thin film, and a multilayer void The advantage of obtaining a low-defect thin film with almost no defects such as multilayer was confirmed.

Claims (15)

90 to 99 vol% of solvent, 0.01 to 9 vol% of monodisperse spherical fine particles having a nano size with a diameter of 1 to 2,000 nm, and 0.05 to 3 vol% of surfactant,
The nano-sized monodisperse spherical fine particles are polystyrene,
The surfactant is a nano-coating composition, characterized in that the formula (2).
[Formula 2]

(In Formula 2, m is 3 to 20, k is 10 to 15) delete delete The method according to claim 1,
The solvent is pure; Methanol, ethanol, isopropyl alcohol, 1-methoxy-2-propanol, 1-butanol, 2-butanol, pentanol, octanol, tetrahydrofurfuryl alcohol, cyclohexanol; Methylethyl ether, diethyl ether, ethylpropyl ether; Ethyl acetate, propylene glycol, monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate; Ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, glycol ether, glycol ether acetate; Propylene carbonate; glycerin; Acetonitrile, tetrahydrofuran, dimethyl formamide, N-methyl formamide, dimethyl sulfoxide, 2-propanol; any one or a mixture of two or more selected from the nano-coating composition for a substrate. delete delete delete The method according to claim 1 or 4,
A nano coating composition for a substrate, characterized in that coating on any one substrate selected from glass, silicon wafer, plastic, ceramic, and metal. A first step of mixing 0.01 to 9 vol% of monodisperse spherical fine particles having a nano size of 1 to 2,000 nm in diameter and 0.05 to 3 vol% of a surfactant in 90 to 99 vol% of a solvent;
A second step of dropping and rotating the coating composition prepared in the first step onto a substrate to spin coating; And
And a third step of evaporating the solvent by drying the spin-coated thin film in the second step,
The nano-sized monodisperse spherical fine particles are polystyrene,
The surfactant coating method of a nano-coating composition, characterized in that the formula (2).
[Formula 2]

(In Formula 2, m is 3 to 20, k is 10 to 15) delete delete The method of claim 9,
Step 1-1 of mixing the spherical fine particles having a nano-sized monodisperse spherical particles and a surfactant in a solvent in the first step in the first solvent; A 1-2 step of mixing a surfactant in a second solvent; The coating method of a nano-coating composition comprising the step 1-3 of mixing the mixture obtained in step 1-1 and the mixture obtained in step 1-2. delete delete The method of claim 9 or 12,
The spin coating of the second step is a coating method of a nano-coating composition, characterized in that coating on any one substrate selected from glass, silicon wafer, plastic, ceramic, and metal.

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