KR101508202B1 - Fabrication method of thermal coating layer comprising vertical-aligned graphene - Google Patents

Abstract

The present invention relates to a method for forming a heat dissipation coating layer including vertically arranged graphenes, and more particularly, to a method for forming a heat dissipation coating layer including graphene solution and binder solution, respectively, And spraying the graphene solution and the binder solution onto the surface of the electronic component or the electronic device to form a heat-dissipating coating layer, wherein the heat-dissipating coating layer is arranged in a direction perpendicular to the surface of the electronic component or the electronic device The present invention relates to a method for forming a heat dissipation coating layer,
The heat dissipation coating layer can dissipate heat in a direction perpendicular to the contact surface with the electronic component or the electronic device, thereby reducing malfunction and heat generation of the electronic device and increasing the service life.

Description

[0001] The present invention relates to a method of forming a heat-dissipating coating layer including graphene,

The present invention relates to a method for forming a heat-radiating coating layer comprising vertically arranged graphene so as to allow heat to be emitted perpendicularly to the contact surface with an electronic component or an electronic device.

The density and thickness of electronic parts and electronic devices have rapidly progressed, and the influence of heat generated from the IC and power components has become serious. For example, a product such as a computer, a portable personal terminal, and a communication device can not dissipate excessive heat energy generated inside the system to the outside, and there is a serious concern about the afterimage problem and the system stability. These thermal energy shorten the life of the product, cause malfunctions and malfunctions, and, in extreme cases, cause explosions and fires.

In recent years, miniaturization and high performance of various electronic parts and electronic devices have resulted in an increase in heat generation, and how heat is efficiently moved and arranged has become a theme of the basic design at the beginning of development. Particularly, there is a strong demand for a heat-dissipating product such as a heat-radiating sheet having high thermal conductivity, thinness and light weight.

In the case of a heat-radiating sheet, it is necessary to install the heat-radiating sheet on an electronic part. Therefore, it is difficult to mold a product having a curved surface, so that a heat radiation coating composition is prepared and coated on electronic parts.

Korean Patent Registration No. 10-0865771 discloses a resin composition comprising 40 to 70 wt% of a binder resin, 5 to 20 wt% of aluminum oxide, 5 to 30 wt% of boron nitride, 5 wt% of zirconium silicate 10 to 40% by weight of at least one additive selected from the group consisting of a dispersant, an anti-settling agent, a defoaming agent, a slip agent, a leveling agent, and an adhesion promoter, Discloses a coating composition for heat dissipation.

Korean Patent Laid-Open Publication No. 2012-0046523 discloses a heat radiation coating composition comprising 130 to 170 parts by weight of inorganic particles, 80 to 120 parts by weight of a binder, 3 to 7 parts by weight of a dispersant and 40 to 60 parts by weight of a solvent. Examples of the inorganic particles exhibiting a heat dissipating effect include oxides such as oxides, cermets, cordierite, germanium, iron oxide, mica, manganese dioxide, silicon carbide, cryptite, carbon, copper oxide, cobalt oxide, nickel oxide, antimony pentoxide, Chromium, silica, alumina, magnesium oxide, titania, zirconia, zinc oxide, barium titanate, zirconium titanate, and strontium titanate.

Korean Patent Laid-Open Publication No. 2012-0039106 discloses a heat-resistant coating composition comprising 50 to 80 parts by weight of at least two inorganic compounds, 30 to 55 parts by weight of a carbonaceous material, 10 to 25 parts by weight of a metal silicate and 100 parts by weight of a solvent It is disclosed that the composition can be coated on an exothermic component to effectively remove heat to improve lifetime characteristics of the exothermic component. In this case, graphite, carbon nano tube, and graphene are used as the carbon-based material, and a conventional wet coating method can be used as a coating method.

Thus, to date, the technical method for thermal spray coating of electronic components has been limited to simple wet coatings such as spray coating or dip coating.

The wet coating method such as spray coating or dip coating using a coating composition has a further advantage in that various functional materials can be produced by coating not only a two-dimensional plate-like substrate but also various types of three-dimensional three-dimensional substrates.

Particularly, when graphite or graphene is used as a carbon-based material, a coating layer formed by wet coating can obtain a heat radiating effect due to the graphene, but the heat radiating property of the graphene itself in a horizontal direction It is limited in terms of dimensions.

Korean Patent Registration No. 10-0865771 Korean Patent Publication No. 2012-0046523 Korean Patent Publication No. 2012-0039106

Accordingly, in the present invention, when graphene, which is one of graphite materials, is used to form a heat-radiating coating layer, various researches have been carried out by focusing on the concept that heat dissipation may occur faster if graphene- As a result, it has been confirmed that excellent heat conduction characteristics can be exhibited by forming the heat-radiating coating layer by arranging the graphene in the vertical direction (3-D) through the electro-spraying process.

Accordingly, it is an object of the present invention to provide a method of forming a heat-dissipating coating layer containing graphene so as to have high thermal conductivity.

In order to achieve the above object, the present invention provides an electronic device or electronic device,

Preparing a graphene solution and a binder solution, respectively; And

And spraying the graphene solution and the binder solution onto the surface of the electronic component or electronic device to form a heat radiation coating layer,

Wherein the heat dissipation coating layer comprises graphene arranged in a direction perpendicular to a surface of an electronic component or an electronic device.

In the present invention, a heat dissipation coating layer is formed on the surface of an electronic component or an electronic device through an electric spray, wherein the heat dissipation coating layer has a structure in which graphenes are vertically arranged with respect to an electronic component or an electronic device. As a result, the heat in the vertical direction of the electronic component or the electronic device is released, thereby exhibiting an excellent heat dissipation effect as compared with the case where the graphenes are arranged in the horizontal direction in the prior art, thereby reducing malfunction and heat generation of the electronic device, have.

1 is a schematic view showing a vertical arrangement of graphene by electrospray according to the present invention;
Fig. 2 is a schematic view showing the electric atomizing device used in the present invention. Fig.
FIG. 3 is a scanning electron microscope sectional image of the vertically arranged graphene prepared in Example 1
4 is a scanning electron microscope image of graphene prepared by the spraying method of Comparative Example 1

Hereinafter, the present invention will be described in more detail.

In the present invention, a heat dissipation coating layer is formed on the surface of the electronic component or electronic device to increase the thermal emissivity of the electronic component or the electronic device. In this case, the heat dissipation coating layer arranges the graphenes in the vertical direction, It can be applied in three dimensions so as to exhibit better heat radiation characteristics.

An "electronic component" referred to throughout the specification of the present invention refers to all components requiring heat dissipation, and specifically refers to a printed circuit board (PCB), a radiator plate, or a radiating sheet.

The term 'electronic device' referred to throughout the present invention means all devices and displays, computers, mobile, lighting, communication devices, game devices, LED lighting, boilers, engines, or motors equipped with the above electronic components.

Specifically, the heat-radiating coating layer of the present invention is prepared by preparing a graphene solution and a binder solution, respectively; And

And then spraying the graphene solution and the binder solution onto the surface of the electronic component or electronic device to form a heat radiation coating layer.

Each step will be described in more detail below.

First, a graphene solution and a binder solution for forming a heat-radiating coating layer are prepared, respectively.

The graphene solution uses graphene dispersed in a solvent.

The method of manufacturing the graphene is not limited thereto, and the graphene in the form of a commercially available flake can be directly purchased and used. For example, in the present embodiment, a substrate having a width of 2 to 3 micrometers was directly manufactured by a chemical stripping method.

The binder is used for the purpose of holding the graphene in an arrayed state and fixing and supporting the graphene so that the graphene can be adhered well to the surface of the electronic component or electronic device.

The material of the binder may be formed by using any material having electrical insulation or conductivity. Representative examples of the polymer include polyacrylate, polymethacrylate, polystyrene, polyester, polyamide, polyimide, polyolefin, cellulose, ethyl cellulose, polyvinyl butyral, polyacrylic ester, silicone resin, rubber resin, polyurethane, vinyl acetate A polymer having conductivity such as polyaniline, polypyrrole, polyacetylene, polythiophene, and PEDOT (poly (3,4-ethylenedioxythiophene)) can be used together with a polymer having an insulating property such as a resin, In one embodiment of the invention, PEDOT is used to vertically align the graphenes on the substrate.

The solvent usable in the graphene solution and the binder solution can sufficiently dissolve or disperse them, and in the case of the binder solution, it can be selected variously according to the material of the binder. Representative examples include water, methanol, ethanol, propanol, isopropanol, butanol, ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethyl ethyl ether, methyl methoxypropionate, ethyl ethoxypropionate ), Ethyl lactate, propylene glycol methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate, diethylene glycol ethyl acetate, (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), gamma -butyrolactone , Diethyl ether, ethylene glycol dimethyl ether, diglyme, tetrahydrofuran (THF), methyl cellosolve, ethyl cellosol , Diethyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol methyl ether, toluene, xylene, hexane, heptane, octane and the like. Formamide was used.

The content of the solvent may be in the range of 0.5 to 1000 parts by weight based on 1 part by weight of the graphene or binder, and the content of the solvent should be such that the nozzle is not clogged during the spraying.

If necessary, the graphene solution and the binder solution may further contain additives such as a dispersing agent for enhancing dispersion stability, a surfactant and a plasticizer, a thickener, a diluent and the like to form droplets upon electrospray. That is, the binder and the graphene solution to be used in the electrospray must have a high dispersion stability so that they can be maintained for a long time without aggregation, lump, and precipitation, and a stable droplet should be formed without clogging the nozzle during electrospray. These properties should be selected for each composition forming the solution and the content range should be limited. If necessary, ultrasonic waves should be applied to the graphene solution to maintain a uniform dispersion state without precipitation in the solution.

Further, in the present invention, a thermally conductive filler may further be included to further improve the heat radiation function of the heat radiation coating layer. This thermally conductive filler is added to one or both of the graphene solution or the binder solution and added to the heat-radiating coating layer by performing the electrospray process described below.

The thermally conductive filler may be one selected from the group consisting of a carbon-based filler, a metal filler, a metal compound filler, a resin filler, and a combination thereof.

Specifically, the carbon-based filler may be carbon black, graphite, carbon nanotubes, and the like. The metal filler may be gold, copper, lead, tungsten, silver, copper, zinc, molybdenum, tin, titanium, aluminum, Invar, An oxide, a hydroxide, a carbide, a nitride or a carbonitride of the metal filler material such as alumina, aluminum hydroxide, silica, magnesia, silicon nitride, aluminum nitride, boron nitride, silicon carbide, aluminum carbide and GaAs As the resin-based filler, epoxy, polyethylene, high-density polyethylene and the like are possible.

Since the thermally conductive filler is used for the purpose of increasing the thermal conductivity of the heat-dissipating coating layer, it should be used within a range that does not reduce the thermal conductivity of the heat-dissipating coating layer.

Even if a thermally conductive filler is introduced, the heat-radiating sheet must have high thermal conductivity, low thermal resistance, and physical stability. The thermally conductive filler factors affecting the physical properties of the heat-radiating coating layer include the shape of the particles, the size of the particles, the amount of addition, and the like, which can be used to meet the thermal conductivity specification of the heat-radiation sheet to be finally applied.

The thermally conductive filler can be used in various forms such as spherical, rod-shaped, and flake-type, but a spherical filler is used to improve the heat conduction by improving the heat flow.

Particle size increases the particle size and increases the thermal conductivity as the content increases. However, since the thermal conductivity decreases as the temperature increases, it is necessary to control the particle size and the content of the thermally conductive filler. A slight modification is possible.

Preferably, the thermally conductive filler is 50 to 50 mu m in the case of metal, metal compound and resin filler spherical particles, and the rod or flake carbon-based filler such as carbon nanotubes is 600 to 1000 nm in length .

In addition, the content of the thermally conductive filler is not more than 50% by weight in the total composition constituting each layer.

Next, the prepared graphene solution and the binder solution are sprayed on the surfaces of electronic parts or electronic devices by using an electric spraying device equipped with a nozzle to form a heat radiation coating layer.

Since the graphen has an electrical characteristic that electrons are transferred along the edge, the direction of graphene can be adjusted when the graphene is stacked on the surface of the electronic component or the electronic device by the flow of the electric field applied in the electrospray process.

1 is a schematic view showing a vertical arrangement of graphene according to the present invention. 1, a syringe through which a solution of graphene 15b is sprayed and a target to be formed with a heat-radiating coating layer (that is, an electronic component or an electronic device) are vertically arranged, an electric field is applied thereto, . For convenience, the electronic components are displayed in the form of a substrate.

In the graphene 15b injected from the syringe, the crystal plane of the graphene 15b is transferred in a direction perpendicular to the substrate in accordance with the flow of the electric field. At this time, no flow or transfer in the vertical direction occurs due to the characteristics of the graphene 15b, thereby enabling alignment of the graphenes 15b in the vertical direction of the electronic parts or the like. However, in processes such as spraying or chemical vapor deposition (CVD) in which no electric field is formed, the graphene 15b may be stacked in the horizontal direction.

At this time, in order to effectively arrange the graphene 15b in the vertical direction, the syringe is disposed on the upper side so that the graphene can be effectively transferred to the electronic part by the gravity along with the electric field. It is preferable to exclude the element which interferes with the stacking of the pin 15b.

In addition, in the present invention, the binder 15a for supporting the graphene 15b together with the graphene 15b is electrically sprayed together to fix the graphene 15b to the substrate 13, which is effectively the target part 13, .

The electrospray device is not particularly limited in the present invention, and it is possible to use a multi-nozzle as well as a device having two nozzles as shown in Fig. 3 to increase the mass productivity. At this time, the electrospray device can be variously modified by those skilled in the art and is shown exaggerated for the sake of understanding, and a known device or configuration necessary for electrospraying can be added to each element. In order to facilitate understanding, two syringes, pumps, and potential difference generators are shown for convenience of illustration in order to spray the binder solution and the graphene solution. However, the syringe, the pump, and the potential difference generator may be provided in one or a plurality of them depending on the solution used or the electrical connection method. That is, the syringe and the pump of each solution can be provided according to the number of the used solutions, and they can be used by being electrically connected to one potential difference generating device.

Referring to FIG. 2, the electrospray apparatus 100 includes a syringe 101a and a syringe 101b having nozzles, a binder solution and a graphene solution are stored in the syringe 101a and 101b, respectively, Syringe pumps 103a and 103b for supplying the graphene solution and potential difference generators 105a and 105b for forming an electric field between the substrate 11 and the syringes 101a and 101b and a binder solution and a graphene solution And a stage 107 for supporting the substrate 11 to be deposited.

The production of the heat-radiating coating layer 15 using the apparatus 100 will be described in more detail.

First, an object part 13 to be stacked is disposed on the electric spraying apparatus 100. In this case, the component 13 may be an electronic component such as a PCB or an electronic device. In FIG. 2,

Next, the binder solution and the graphene solution are prepared, respectively, and the solutions are injected into the syringes 101a and 101b using the syringe pumps 103a and 103b, respectively. At this time, the nozzles of the syringes 101a and 101b are disposed so as to be perpendicular to the target component 13.

Next, electricity is applied to the nozzle and the stage 107 by using the potential difference generator 105a to form an electric field having a flow in the vertical direction inside the chamber.

Next, a droplet of the binder solution is sprayed onto the target component 13 from the syringe 101a, and the binder layer 15a is laminated on the target component 13.

Next, a graphene solution 15b is formed on the binder layer 15a by spraying the graphene solution from the syringe 101b in a droplet state using a potential difference generator 105b connected to the syringe 101b containing the graphene solution, .

Next, after the completion of the spraying of the graphene solution, the binder solution and the solvent or various additives contained in the graphene solution are removed through a drying process to form a graphene 15b on the target component 13, To obtain a heat-radiating coating layer (15) supported by the heat-radiating layer (15).

Drying conditions vary depending on the solvent used and are performed in a temperature range of 15 to 200 ° C so that the solvent can be sufficiently removed.

If necessary, heat treatment is performed at 200 to 600 ° C to remove the binder to obtain a thermal spray coating layer 15 made of only graphene.

The heat-radiating coating layer 15 manufactured through the above-mentioned steps has various factors such as the size of the graphene used, the material of the binder, the solvent used, the kind and content of the various additives, the concentration, The morphology of the graphene can be controlled by adjusting factors such as the distance between the nozzle and the substrate, the temperature, and the flow rate.

In addition, considering the factors in the electrospray process, the distance between the nozzle and the substrate, and the strength of the electric field applied at this time, should be considered so that the graphene ejected from the nozzle can be transported with a perpendicular direction to the binder.

Specifically, if the distance between the nozzle and the substrate is insufficient, the graphene may not have sufficient vertical orientation, and if it is too far, there is a fear that the manufacturing time may become longer, and the distance between the nozzle and the substrate may be 1 to 15 cm .

In addition, electricity is applied for spraying in a droplet state, and the droplet tends to be formed smaller as the voltage of the applied electric power is increased. Thus, a voltage is applied in the range of 5 to 50 kV, preferably in the range of 10 to 25 kV, so that there can be one graphene in one droplet for uniform graphene arrangement, i. E., To form micron level droplets.

In addition, it is preferable to carry out the spray flow rate at 0.01 ml / h to 5 ml / h and use the nozzle diameter of 0.005 to 0.5 mm.

In addition, it is preferable to apply a high voltage when the substrate is far from the nozzle and a low voltage when the substrate is far from the nozzle. It is also desirable to consider the magnitude of the voltage as well as the distance from the nozzle to the substrate. And the substrate was performed at 20 kV.

The heat-radiating coating layer is formed on the surface of the electronic component or the electronic device through the above-described steps. At this time, the heat-radiating coating layer may be formed to have a thickness of 10 nm to 0.1 mm, though it may vary in thickness depending on heat radiation specifications required for electronic parts or electronic equipment. If the thickness is less than the above range, sufficient heat radiation functionalities can not be ensured. On the other hand, if the thickness exceeds the above range, the effect of improving the heat dissipation function is no more and the processing time becomes longer.

Particularly, graphene, which forms a heat-radiating coating layer, has a two-dimensionally thermal conduction and functions as a heat-dissipating layer. As graphenes are arranged vertically, heat conduction is possible in three dimensions (vertical direction or Z direction) The present invention can be applied to various electronic components and electronic devices in which functions are required.

The heat dissipation coating layer forms a transparent coating layer. The electronic parts or electronic devices are applied to various electronic products such as notebook computers, mobile phones, TVs, printed circuit boards (PCBs), and LEDs. By effectively releasing it, it reduces the malfunction of equipment caused by conventional heat, improves reliability, and increases life span.

The electrospray method for manufacturing the heat radiation coating layer of the heat-radiating sheet is advantageous in terms of cost as compared with the expensive equipment for conventional vapor deposition, and a coating layer having a transparent thickness and uniform thickness can be formed even for three-dimensional components. In addition, not only the production time can be shortened, but also the process can be performed at normal temperature and pressure, so that it can be easily applied to a mass production process.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Of course.

Hereinafter, the present invention will be described in more detail with reference to examples. The following examples are only illustrative of the present invention, but the present invention is not limited thereto.

[Example]

Example 1: Graphene coating by electrospray

A graphene solution was prepared by dispersing 0.001 g of graphene in 1 ml of DMF, and 1 g of PEDOT and 5 ml of DMF were dissolved to prepare a binder solution. The graphene and binder solutions were each injected into a syringe of an electrospray device. A silicon wafer was used as the substrate. The distance between the needles of the syringe and the substrate was adjusted to 10 cm, and an electric field of 20 kV was applied between the syringe and the substrate.

At this time, the deposition by electrospray was performed on the substrate with the binder solution for 5 minutes, and then, through the nozzle of the graphene solution, the support layer was deposited to a thickness of about 6 탆. And dried at 100 DEG C to form a heat-radiating coating layer containing graphene / PEDOT on the substrate. Referring to FIG. 3, it can be seen that the graphenes are vertically arranged at an angle on the substrate.

Comparative Example 1: Simple spray coating

0.001 g of graphene and 1 g of PEDOT were added to 10 ml of DMF to prepare a spray solution and spray-sprayed to form a 10 탆 thick graphene / PEDOT coating layer on the substrate.

Experimental Example  1: Property of heat-radiating coating layer

The heat dissipation characteristics of the graphene coating layer and the adhesion of the coating layer in Example 1 and Comparative Example were evaluated.

(1) Thermal conductivity: Measured according to ASTM D 5470 method.

(2) Change in surface temperature: An LED lamp was attached to the substrate on which the heat radiation coating layer was formed, and the temperature of each substrate surface was measured after an elapse of 1 hour after passing a current of 500 mA. At this time, only the substrate on which the heat radiation coating layer was not formed was evaluated as a control example.

(2) Adhesiveness: 100 squares were formed in 1 cm square by 1 mm squares in a unit of 1 mm squares, then adhered with a Scotch tape, and then evaluated for adhesion through the number of squares detached and dropped. In Table 1, it is evaluated as good (O) when the number of squares falling out of 100 squares is less than 5. When the number of squares falling from 6 to 25 is evaluated as normal (△), when the number of squares falling is 26 or more And evaluated as defective (X).

Thermal conductivity Surface temperature Attachment Example 1 220.8 W / m.k 57 ℃ ○ Comparative Example 1 4.5 W / m.k 78 ℃ ○ Control Example 0.5 W / m.k 95 ℃ -

Referring to Table 1, the thermal conductivity of the substrate coated with vertically arranged graphene of Example 1 was 220.8 W / mk, and the thermal conductivity was about 49 times or more at 4.5 W / mk in Comparative Example 1 in which simple spray coating was applied The degree of improvement was improved. These results show that the heat dissipation characteristics can be improved, that is, the heat can be rapidly discharged in the vertical direction, as compared with the case where the vertically arranged graphenes are arranged in the horizontal direction. This is also known from the result of the measured surface temperature, and it can be expected that the heat removal effect of electronic parts and electronic devices is excellent and the lifetime characteristics can be improved.

Further, it can be seen that the heat-radiating coating layer of Example 1 has excellent adhesiveness and can be applied to various products.

The method according to the present invention can improve the lifetime as well as reduce malfunction and heat generation of electronic devices due to excellent heat radiation characteristics by forming a heat radiation coating layer on various electronic parts and electronic equipment.

11: substrate 13: target part
15a: binder 15b: graphene
100: Electrospray device
101a, 101b: a syringe
103a, 103b: Syringe pump
105a and 105b:
107: stage

Claims (10)

To increase the thermal emissivity of electronic components or electronic devices,
Preparing a graphene solution and a binder solution, respectively; And
And spraying the graphene solution and the binder solution onto the surface of the electronic component or electronic device to form a heat radiation coating layer,
Wherein the heat-radiating coating layer comprises graphene arranged in a direction perpendicular to a surface of an electronic component or an electronic device. The resin composition according to claim 1, wherein the binder is selected from the group consisting of polyacrylate, polymethacrylate, polystyrene, polyester, polyamide, polyimide, polyolefin, cellulose, ethyl cellulose, polyvinyl butyral, polyacrylic ester, , A polyurethane, a vinyl acetate resin, an epoxy resin, polyaniline, polypyrrole, polyacetylene, polythiophene, PEDOT (poly (3,4-ethylenedioxythiophene) Wherein the heat-dissipating coating layer is formed of a thermosetting resin. The method according to claim 1, wherein the solvent for preparing the graphene solution and the binder solution are the same or different from each other and are selected from the group consisting of water, methanol, ethanol, propanol, isopropanol, butanol, ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, Propylene glycol dimethyl ether, ethylene glycol dimethyl ether, methyl methoxypropionate, ethyl ethoxypropionate (EEP), ethyl lactate, propylene glycol methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, But are not limited to, sorbic acid, sorb acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate, diethylene glycol ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, dimethylformamide (DMF) (DMAc), N-methyl-2-pyrrolidone (NMP), gamma -butyrolactone, diethyl ether, ethylene glycol di Methyl ethyl ketone, diethyl ether, diglyme, diglyme, tetrahydrofuran (THF), methyl cellosolve, ethyl cellosolve, diethyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol methyl ether, Xylene, hexane, heptane, octane, and combinations thereof. The method for forming a heat-dissipating coating layer according to claim 1, [2] The method of claim 1, wherein the graphene solution is prepared by mixing 0.5 to 1000 parts by weight of a solvent with respect to 1 part by weight of graphene. The method for forming a heat dissipation coating layer according to claim 1, wherein the binder solution is mixed with 0.5 to 1000 parts by weight of a solvent relative to 1 part by weight of the binder. The method according to claim 1, further comprising a thermally conductive filler selected from the group consisting of a carbon-based filler, a metal filler, a metal compound filler, a resin filler and a combination thereof in any one of the graphene solution or the binder solution Wherein the heat-dissipating coating layer is formed on the substrate. The method of claim 6, wherein the carbon-based filler is carbon black, graphite, or carbon nanotube, and the metal filler is selected from the group consisting of gold, copper, lead, tungsten, silver, copper, zinc, molybdenum, tin, Invar or Kovaar and the metal compound filler is a metal selected from the group consisting of gold, copper, lead, tungsten, silver, copper, zinc, molybdenum, tin, titanium, aluminum, Wherein the resin-based filler is an oxide, hydroxide, carbide, nitride or carbonitride, and the resin-based filler is epoxy, polyethylene, or high-density polyethylene. The method for forming a heat dissipation coating layer according to claim 1, wherein the heat dissipation coating layer has a thickness of 10 nm to 0.1 mm. 3. The method of claim 1, wherein the electrospray is performed by applying a voltage between 5 and 50 kV between the plate and the syringe, spacing them by 5 to 20 cm, performing a spray flow rate from 0.01 ml / h to 5 ml / h, And the nozzle diameter is 0.005 to 0.5 mm. The method of claim 1, wherein the electrospray
A binder solution and a graphene solution are respectively stored for electro-spraying, and a syringe having a nozzle,
A syringe pump for supplying the binder solution and the graphene solution to the syringe,
A potential difference generating device for forming an electric field between the substrate and the syringe, and
Wherein a binder solution and a stage for supporting a substrate on which the graphene solution is deposited are used.

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