KR20140080929A - Composition for coating of graphene, manufacturing method thereof and graphene coated steel sheet - Google Patents

Abstract

There is provided a graphene coating composition comprising an oxidized graphene modified with an acrylate, an oligomer, a monomer, and a photoinitiator, a process for producing the same, and a steel sheet coated thereon.
According to the present invention, it is possible to provide a coated steel sheet having high workability, lubricity, corrosion resistance, conductivity, high gloss and transparency as well as high gloss and scratch resistance, and can increase the curing efficiency of the coating composition.

Description

TECHNICAL FIELD The present invention relates to a graphene coating composition, a method for producing the graphene coating composition, and a graphene-

The present invention relates to a graphene coating composition, a method for producing the same, and a graphene coated steel sheet.

UV curing technology has been developed to provide high gloss and scratch resistance characteristics that can not be realized in conventional PCM, and various UV coating compositions have been developed in accordance with necessary physical properties.

However, in the case of photocuring reaction such as UV, the crosslinking density of the coating film is high due to the network structure between the compositions, and scratch resistance is very strong. However, the use of the product for post-processing is limited.

In addition, when a material having no functional group capable of participating in the photo-curing reaction is included in the coating composition, the efficiency of photo-curing reaction is lowered, and thus there are many restrictions in selecting a composition for photocurable coating.

As an example of a material having no functional group capable of participating in the photo-curing reaction, in the case of graphene, there is a technique of applying a polymer brush to graphene through radical polymerization by UV for use in a composition for UV coating. However, this technique has applied UV curing to graft polymers to graphene and does not allow graphene to participate directly in the UV curing reaction. If the graphene does not participate directly in the UV reaction, graphene acts as an impurity that reduces the curing efficiency.

As an alternative to solve these problems, graphene is mixed with a photo-curing resin such as UV resin to allow graphene to participate in the photo-curing reaction directly, thereby exhibiting the intrinsic properties of graphene and the excellent physical properties provided by the UV cured coating Development of technology to make it necessary.

One aspect of the present invention is to provide a coating composition utilizing graphene, which is a material having no functional group capable of participating in a photo-curing reaction, as a part of a photocurable coating composition, and a method for producing the same.

Another aspect of the present invention is to propose a coated steel sheet in which the properties of the photocurable coating and the properties of graphene are simultaneously realized.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

In order to accomplish the above object, one aspect of the present invention provides a graphene coating composition comprising an oxidized graphene modified with an acrylate, an oligomer, a monomer, and a photoinitiator.

In another aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising preparing a graphene oxide, replacing the functional group of the graphene oxide with an acrylate to form an oxide graphene modified with an acrylate, A photoinitiator, a photoinitiator, a monomer, and a photoinitiator.

Another aspect of the present invention provides a graphene-coated steel sheet comprising a base steel sheet and a coating layer composed of the cured product of the coating composition on the base steel sheet.

According to one aspect of the present invention, it is possible to provide a coated steel sheet having high workability, lubricity, corrosion resistance, conductivity, high gloss and transparency as well as high gloss and scratch resistance.

According to another aspect of the present invention, the curing time can be shortened by increasing the curing efficiency even if a small amount of photoinitiator is used.

Hereinafter, the graphene coating composition of the present invention, the method of producing the same, and the graphene-coated steel sheet will be described in detail so that those skilled in the art can easily carry out the present invention.

The present invention proposes a coating composition capable of realizing high gloss and scratch resistance, which is a characteristic of a photocuring technique such as UV, as well as conductivity, which is a characteristic of graphene, together.

However, since graphene has no functional group capable of participating in the photocuring reaction, there is a problem that the photocuring reaction efficiency is lowered. To solve this problem, it is necessary to introduce a functional group capable of participating in the photocuring reaction into graphene. For this purpose, graphene graphene, which is capable of modifying graphene and attaching functional groups, must be prepared. The graphene oxide may have a functional group such as a hydroxyl group, a carbonyl group, a carboxyl group, an amine group and the like, though not necessarily limited thereto. Such graphene oxide is excellent in dispersibility in a solution, but functional groups such as hydroxyl group, carbonyl group, carboxyl group and amine group attached to the graphene oxide inhibit the photo-curing reaction by inhibiting the radical resonance stabilization effect. In addition, when the photocurable composition contains particles or the like, it can not participate in the curing reaction, and thus the curing efficiency can be lowered.

Therefore, in order to solve this problem, in the present invention, it is possible to participate in the photocuring reaction by substituting the functional group of the modified graphene (graphene oxide) with an acrylate, and as a result, a side reaction is not caused, So that the curing efficiency can be greatly improved. In addition, the double bonds at the edges of some graphenes increase the curing rate by participating in the photo-curing reaction, and the curing efficiency can be increased and the curing time can be shortened even when a small amount of photoinitiator is used.

Therefore, graphene modified with a functional group capable of participating in the photo-curing reaction, typically graphene modified with acrylate, is required.

First, graphene oxide (GO) is prepared.

Examples of the functional group of the GO to be modified with an acrylate functional group include a hydroxyl group, a carbonyl group, a carboxyl group, and an amine group. Such functional groups of GO are substituted with acrylates to prepare acrylate-modified graphene grains. The method of attaching the acrylate functional group to the GO may differ depending on the kind of the acrylate.

For example, when a hydroxyalkyl acrylate is attached to graphene, the acrylate polymerization proceeds by a hydrogen transfer reaction between a diisocyanate and a polyol having an active hydrogen. First, the hydroxyl group of the GO functional group is reacted with an isocyanate group To which a hydroxyalkyl acrylate can be attached.

Specifically, the compound containing a functional group capable of reacting with the hydroxyl group of the graphene oxide is a compound having an isocyanate group, an alkoxy group, or a carboxyl group in its structure; A compound containing a halogen atom; Or a cyclic anhydride.

More specifically, the compound containing a functional group capable of reacting with the hydroxyl group of the graphene oxide may be represented by the formula -N═C═O, RO═CX, R-COOH, R 4-x-Si- (R ') x, R '. ≪ / RTI > Wherein R represents C1-30 alkyl, C2-30 alkyl, C2-30 alkynyl, C5-12 aryl, or C6-24 aralkyl. The R may be substituted or unsubstituted, respectively, by one or more substituents selected from the group consisting of C1-12 alkyl, C2-12 alkyl, C2-12 alkynyl and C5-12 aryl. R 'represents C1-12 alkoxy, x represents an integer of 1 to 3, and y represents an integer of 1 to 4.

More specifically, the compound containing a functional group capable of reacting with the hydroxyl group of the graphene oxide is benzyl isocyanate, hexyl isocyanate, 3-isopropenyl-a, a-dimethylbenzyl isocyanate, methacryloyl chloride, Fatty acid succinic anhydrides, and fatty acid succinic anhydrides.

After the graphene oxide is dissolved in an organic solvent, a compound containing a functional group capable of reacting with a hydroxyl group is mixed. Examples of usable organic solvents include acetone, methanol, ethanol, 1-propanol, ethylene glycol, DMSO, DMF, NMP, THF and the like.

At this time, (graphene oxide): (a compound containing a functional group capable of reacting with a hydroxyl group) is preferably mixed in a molar ratio of 1: 2 to 2.1. When the molar ratio is less than 1: 2, unreacted hydroxy groups may be present to cause problems such as low curing degree and low polymerization rate during polymerization. When the molar ratio is larger than 1: 2.1, unreacted functional groups (isocyanate groups Etc.) are present in the reaction product, a purification process is required to remove them, or they may remain in the final product, which may lead to toxicity problems and deteriorate film appearance.

A compound containing a functional group capable of reacting with a carbonyl group, a carboxyl group, an amine group or the like in addition to the hydroxyl group can be mixed at the same molar ratio.

The reforming temperature of the graphene oxide is preferably 30 to 80 캜. If the temperature is lower than 30 ° C, the reaction time becomes too long. If the temperature is higher than 80 ° C, it may be difficult to control the reaction heat due to a high reaction rate. As a side reaction of functional groups (isocyanate etc.), biuret and allophanate ) Formation reaction may occur.

Next, the graphene oxide modified with isocyanate or the like is blocked with an alkyl acrylate such as hydroxyethyl acrylate (HEA) or hydroxyethylmethyl acrylate (HEMA).

Through the above process, the hydroxyl group in the functional group of the graphene oxide is reacted with the isocyanate group, and the hydroxyalkyl acrylate is attached to the hydroxyl group, thereby obtaining the oxidized graphene modified with the acrylate.

Next, the graphene coating composition of the present invention is prepared by mixing oligomer, monomer, and photoinitiator with the acrylate modified graphene.

The graft coating composition comprises 1 to 50% by weight of the graft modified with an acrylate, 10 to 80% by weight of the oligomer, 10 to 80% by weight of the monomer, and 0.1 to 30% by weight of the photoinitiator .

If the amount of grafted oxide grains is less than 1 wt%, the amount of graphene is too small and the graphene is difficult to be present in the surface layer of the coating layer. When the content of graphene is more than 50 wt%, the content of graphene is too high, It is difficult to take advantage of the same UV coating.

The oligomer may be contained in the graphene coating composition in an amount of 10 to 80% by weight, preferably 30 to 70% by weight. If the content of the oligomer is less than 10% by weight, the photopolymerization reaction proceeds rapidly, and the crosslinking density is increased to increase the brittleness of the coating film. When the content of the oligomer exceeds 80% by weight, the photopolymerization reaction rate is lowered, There is a possibility that a UV irradiation amount for curing the coating film is required to be large or a UV irradiation time is prolonged.

The monomer may be contained in an amount of 10 to 80% by weight, preferably 30 to 70% by weight, based on the graphene coating composition. If the content of the monomer is less than 10% by weight, the photopolymerization reaction rate is lowered, the crosslinking density is difficult to control, the UV irradiation amount for curing the coating film is increased, the UV irradiation time is prolonged, As the photopolymerization reaction proceeds rapidly, the cross-linking density increases and the brittleness of the coating film may increase.

The photoinitiator may be contained in an amount of 0.1 to 30% by weight, preferably 1 to 10% by weight, based on the graphene coating composition. When the content of the photoinitiator is less than 0.1% by weight, the photopolymerization reaction does not occur or the photopolymerization reaction occurs very slowly, so that the coating film can not be cured by UV irradiation or the curing time may be prolonged. On the other hand, The photoinitiator may remain in a state of being transferred to the radical form due to the photoreaction, thereby suppressing the photopolymerization reaction or lowering the physical properties of the coating film.

The acrylate which can be used to modify the GO may be one or a mixture of one or more of monofunctional acrylic monomers, bifunctional acrylic monomers and polyfunctional acrylic monomers.

Wherein the monofunctional acrylic monomer is selected from the group consisting of acrylic morpholine (ACMO), tetrahydrofurfuryl acrylate (THFA), hydroxyethyl acrylate (HEA), hydroxypropyl acrylate (HPA) and isobornyl acrylate Can be selected from the group.

The bifunctional acrylic monomer may be selected from the group consisting of diethylene glycol diacrylate (DEGDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), hexanediol diacrylate (HDDA), polyethylene glycol 400 diacrylate (PEG 400DA), and ethylene glycol 600 diacrylate (PEG 600DA).

The polyfunctional acrylic monomer may be selected from the group consisting of trimethyl propane ethoxylate triacrylate and trimethyl propane triacrylate.

The oligomer serves as a binder in the coating composition.

Wherein the oligomer is selected from the group consisting of epoxy acrylate, urethane-based modified epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, acrylic acrylate, silicone acrylate, melamine acrylate, acrylic acrylate, polythiol acrylate derivatives, The polyol component may also be a mixture of two or more selected from the group consisting of acetal acrylates.

The epoxy acrylate may be aromatic dicarboxylic epoxy acrylate, novolac epoxy acrylate, or aliphatic epoxy acrylate.

More specifically, the oligomer preferably contains 25 to 45% by weight of urethane-based modified epoxy acrylate and 10 to 25% by weight of urethane acrylate relative to the graphene coating composition. More preferably 30 to 38% by weight of urethane-based modified epoxy acrylate and 15 to 20% by weight of urethane acrylate. In addition, in the present invention, the weight average molecular weight of the oligomer is not particularly limited and may be, for example, 1000 to 5000, preferably 1000 to 3000.

When the content of the urethane-modified epoxy acrylate is less than 25% by weight, the corrosion resistance and scratch resistance are poor. When the content of the urethane-modified epoxy acrylate is more than 45% by weight, the viscosity of the coating increases.

If the content of the urethane acrylate is less than 10% by weight, the hardness of the coating film is increased to result in poor bending properties (processability), specific bending workability and adhesiveness, and if it exceeds 25% by weight, can do.

The monomer serves as a binder in the coating composition.

The monomer may be one or more of a monofunctional monomer, a bifunctional monomer and a polyfunctional monomer. More specifically, these monomers may be acrylic monomers.

The monofunctional monomer used as the monomer may be one or a mixture of two or more selected from the group consisting of alkyl acrylate, aryl acrylate, alkoxy acrylate, and tetrahydrofurfuryl acrylate.

The difunctional monomer used as the monomer may be one or a mixture of two or more selected from the group consisting of tripropylene glycol diacrylate and hexanediol diacrylate.

The multifunctional monomer used as the monomer may be one or a mixture of two or more members selected from the group consisting of trimethyl propane ethoxylate triacrylate and trimethyl propane triacrylate.

More specifically, the monomer preferably comprises 5 to 40% by weight of a monofunctional monomer and 5 to 30% by weight of a bifunctional monomer relative to the graphene coating composition.

When the content of the monofunctional monomer is less than 5% by weight, the viscosity increases and the adhesion is poor. When the content of the monofunctional monomer is more than 40% by weight, the ultraviolet curing property decreases and the productivity may be reduced.

When the content of the bifunctional monomer is less than 5% by weight, the viscosity of the composition increases. When the content of the bifunctional monomer exceeds 30% by weight, the overall coating property may be adversely affected.

The photoinitiator plays a role in initiation of photo-curing reaction such as UV in the coating composition.

The photoinitiator may be benzophenone, diphenoxycibenzophenone, anthraquinone, xanthone, thioxanthone, or benzyl, but is not limited thereto. Specifically, commercially available initiators such as Micure HP-8, Irgacure 819, Darocur TPO, and Micure CP-4 may be used, but the present invention is not limited thereto.

In the composition of the present invention, the content of the photoinitiator is not particularly limited, but 0.1 to 10% by weight is preferably used. If the amount is less than 0.1% by weight, the curing may not be performed, and if it exceeds 10% by weight, the physical properties may be deteriorated.

The graft coating composition may contain 0.1 to 15% by weight, preferably 0.3 to 10% by weight, more preferably 0.5 to 6% by weight of an additive. By incorporating the additive into the coating composition within the above content range, the effect of the additive can be exhibited without changing the physical properties required for the UV curable coating composition.

The type of the additive is not particularly limited and any additive conventionally used in this field can be used. Preferably, the additive is a defoaming agent, a leveling agent, an adhesion promoter, a light stabilizer, an antioxidant, , A smoothing agent, a dispersant, an antistatic agent, a silane coupling agent, a plasticizer, an organic filler, and a mixture thereof.

The antifoaming agent is used to remove bubbles generated during the coating operation using the graphene coating composition of the present invention. Specific examples thereof include TEGO Airex 920, TEGO Airex 932, BYK 088 or BYK 1790, But is not limited thereto.

Specific examples of the leveling agent include, but are not limited to, TEGO Glide 410, TEGO Glide 440, TEGO Rad 2250, BYK-UV 3500, and BYK-UV 3510. .

The adhesion promoter is for enhancing the adhesion of the photocurable coating composition to the undercoating layer. Specific examples thereof include acrylate-based adhesion promoters such as hydroxyethyl acryloyl phosphate or hydroxyethyl methacrylate phosphate , But is not limited thereto.

The light stabilizer may be used to facilitate storage stability, and examples of the stabilizer include a phenolic antioxidant, an alkylated monophenol, an alkylthiomethyl phenol, a hydroquinone, an alkylated hydroquinone, a tocopherol, a hydroxylated thiodiphenyl Ether, alkylidene bisphenol, O-, N- and S-benzyl compounds, hydroxybenzylated malonates, aromatic hydroxybenzyl compounds, triazine compounds, amine antioxidants, arylamines, diarylamines, polyarylamines , Acylaminophenol, oxamide, metal deactivators, phosphites, phosphonites, benzylphosphonates, ascorbic acids, hydroxylamines, nitrones, thiosynergists, benzofuranones, or indolinones It does not.

Specific examples of the light stabilizer include products of BASF such as Tinuvin 292, Tinuvin 144 or Tinuvin 622LD; And SANKYO products such as Sanol LS-770 (sanol LS-770), Sanol LS-765 (sanol LS-765), Sanol LS-292 (sanol LS-292) or Sanol LS-744 .

Antioxidants used as stabilizers prevent oxidation reactions and thus facilitate storage. Typical examples that can be used as such antioxidants include Irganox 1010, Irganox 1035, Irganox 1076, 1076) or Irganox 1222 (BASF).

The ultraviolet absorber is a material that helps absorb UV light in order to increase the reaction efficiency in the UV reaction. Specific examples of the ultraviolet absorber include Tinuvin P, Tinuvin 234, Tinuvin 320, Products of BASF such as Nubin 328 (Tinuvin 328); And Sumisorb 110, Sumisorb 130, Sumisorb 140, Sumisorb 220, Sumisorb 250, Sumoisorb 320, (Sumisorb 320) or Sumisorb 400 (Sumisorb 400), but are not limited thereto.

Further, the thermal agglomerating agent is added in order to prevent the reaction from being terminated due to heat and to cause a photoreaction by UV. HQ, THQ, HQMME and the like are preferable as the thermal polymerization inhibitor.

The smoothing and dispersing agent may be selected from commercial additives such as BYK, TEGO and EFKA.

The antistatic agent is added for antistatic purposes in the UV reaction. Examples of the antistatic agent include nonionic systems such as polyoxyethylene alkyl ethers, polyoxyethylene amines, glycerin or sorbitol fatty esters, alkyl sulfonates such as alkyl sulfonates, alkyl Benzenesulfonate, alkylsulfate, alkylphosphate and the like, quaternary ammonium salts or mixtures thereof.

The silane coupling agent may be added to increase the adhesive strength of the coating composition of the present invention.

Specific examples of the silane coupling agent include methacryloxypropyltrimethoxysilane, gamma-methacryloxypropylethoxysilane, gamma-chloropropylmethoxysilane, vinyltriethoxysilane, vinyltris (beta-methoxyethoxy ) Silane, vinyltriacetoxysilane, gamma-glycidoxypropyltrimethoxysilane, gamma-glycidoxypropyltriethoxysilane, beta - (3,4-epoxycyclohexyl) ethyltrimethoxysilane, But are not limited to, silane, gamma-mercaptopropylmethoxysilane, gamma-aminopropyltriethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyltrimethoxysilane, and mixtures thereof.

The thus prepared graphene coating composition is coated on a base steel sheet and cured by UV, electron beam or the like to form a coating layer in the form of a cured product to prepare a graphene coated steel sheet.

The base steel sheet is not limited thereto, but may be a cold-rolled steel sheet; galvanized steel; Galvanized electroplated steel sheet; Hot - dip galvanized steel; Aluminum-plated steel sheet; A coated steel sheet containing cobalt, molybdenum, tungsten, nickel, titanium, aluminum, manganese, iron magnesium, tin, copper or a mixture thereof; An aluminum alloy plate to which silicon, copper, magnesium, iron, manganese, titanium, zinc or a mixture thereof is added; Galvanized steel plates coated with phosphate; Or a hot-rolled steel sheet.

The coating composition may be applied to a steel sheet by a method commonly used in the art, for example, a coating method such as dip coating, spray coating, roll coating or bar coating. When the applied coating composition is cured with ultraviolet rays, the wavelength of the ultraviolet ray is preferably 400 nm or less. As a light source for irradiating the ultraviolet ray, a metal halide, a medium pressure mercury lamp, a high pressure mercury lamp, an H bulb without electrode, a D bulb, a V bulb (fusion, USA) can be selected and used as needed. The amount of ultraviolet light to be irradiated is usually 0.1 to 10 J / cm ² , which can be suitably adjusted according to the composition of the ultraviolet ray hardening resin composition and the user's choice.

The thickness of the coating layer is preferably 0.5 to 20 占 퐉. If the thickness of the coating layer is less than 0.5 m, the cured product of the UV curable coating composition may not be sufficient and scratch resistance and gloss may be lowered. When the thickness exceeds 20 m, the coating thickness is too thick, can do.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are provided to aid understanding of the present invention and should not be construed as limiting the present invention.

[ Example ]

One. Oxidized graphene  Ready

The oxidized graphene used for the practice of the present invention was prepared using the generally known Hummer method.

2. Acrylate Oxidized graphene  Modification

The reaction solution in which the graphene oxide was dissolved in THF and the benzyl isocyanate were mixed at a molar ratio of 1: 2 and reacted at 45 ° C to modify the functional group (for example, hydroxyl group) of the oxidized graphene to an isocyanate. Then, hydroxyethyl acrylate (HEA) was slowly added to the isocyanate-modified oxide graphene and the reaction was carried out at about 40 ° C to prepare an acrylate-modified oxide graphene. Through the FT-IR analysis in real time, the intensity of the NCO peak detected at 2270-3 cm ^-1 was observed, and the completion time of the reaction and the amount of consumed isocyanate were determined.

3. Grapina  Preparation of coating compositions

Acrylate modified graphene, bifunctional oligomer [urethane acrylate, SUPER RESIN 1327, Samhwa Paint, Korea], polyfunctional oligomer [urethane acrylate, SUPER RESIN 1315, Samhwa Paint, Korea], monofunctional monomer 1 [ (THDA), SR285, Sartomer, USA), monofunctional monomer 2 [isobornyl acrylate (IBOA), SK-UCB, Korea], difunctional monomer 1 [hexanediol diacrylate (HDDA) ( Mirocer M200, Miwon, Korea), difunctional monomer 2 [tripropylene glycol diacrylate (TPGDA), Mi Won Sang, Korea], photoinitiator 1 [Darocur 1173, Ciba Chemicals, Switzerland], photoinitiator 2 [IRGACURE 184, CIBA , TEGO Airex 920, Evonik, Germany) and leveling agent (TEGO Rad 2250, Evonik, Germany) as additives, hydroxyethyl acryloylphosphate as an adhesion promoter, It was prepared. The component contents of the coating composition were varied as shown in Table 1 for Examples and Comparative Examples. The units represent the respective weight percentages for 100 wt% of the total coating composition.

Inventory 1 Inventory 2 Inventory 3 Honorable 4 Inventory 5 Inventory 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Bifurcated
Oligomer 35 35 35 30 30 30 35 35 30 Multifunctional
Oligomer 15 15 10 10 10 5 15 10 10 Consistency
Monomer 1 15 15 15 15 10 15 15 15 25 Consistency
Monomer 2 5 5 5 - 5 - 10 10 15 Bifurcated
Monomer 1 10 5 5 15 5 10 10 15 5 Bifurcated
Monomer 2 5 5 5 - 5 - 5 - 5 Acrylate modified graphene oxide 5 10 15 20 25 30 0 0 0 additive 4 4 4 4 4 4 4 4 4 Photoinitiator 1 3 3 3 3 3 3 3 3 3 Photo initiator 2 2 2 2 2 2 2 2 2 2 Adhesion promoter One One One One One One One One One system 100 100 100 100 100 100 100 100 100

4. Grapina  Manufacture of coated steel sheet

The graphene coating compositions prepared according to Examples 1 to 6 and Comparative Examples 1 to 3 were coated on the surface of a galvanized steel sheet with a # 3 bar coater, and then nitrogen was added thereto. Then, an ultraviolet ray irradiator [ Fusion 600vps, Fusion Co., USA) was irradiated with ultraviolet rays at a light intensity of 100 to 2000 mJ / cm ² to form a coating film of 3 to 5 탆 to treat the surface of the steel sheet.

5. Analysis of physical properties of coated steel

The appearance, gloss, scratch resistance, corrosion resistance, bending property, lubricity, adhesion, and conductivity of each surface-treated steel sheet were measured and shown in Table 2 below.

Exterior Polish Scratch resistance Corrosion resistance Bending property Lubricity Attachment conductivity Inventory 1 ○ ◎ F ↑ ○ △ ○ ○ ○ Inventory 2 ○ ◎ F ↑ ○ ○ ○ ○ ○ Inventory 3 ○ ◎ F ↑ ○ ○ ○ ○ ○ Honorable 4 ○ ◎ F ↑ ○ ○ ○ ○ ○ Inventory 5 ○ ◎ F ↑ ◎ ○ ○ ○ ◎ Inventory 6 ○ ◎ F ↑ ◎ ○ ○ ○ ◎ Comparative Example 1 ○ △ B ↓ ○ △ △ ○ × Comparative Example 2 △ △ B ↓ △ × △ ○ × Comparative Example 3 ○ △ B ↓ △ × × △ ×

[Measurement method and evaluation standard]

(1) Appearance

The appearance of the coated film was evaluated to be good without any foreign matter and uncoated areas. The evaluation results were evaluated in the following manner.

◎: No abnormality.

○: There is little tea.

C: Partial crater ring.

X: Multiple cratering and yellowing.

 (2) Glossiness

Using the gloss meter, the angle selector was fixed at 60 ° and the black gloss plate was placed on the sample table. After turning on the switch, it was left for 1 ~ 2 minutes. After adjusting the standardizing control knob until the gloss of the standard plate became 96.4%, the specimen to be tested was replaced with the standard plate and the scale of micro amperes was read And then give an average value.)

⊚: 85 or more

?: 70 to 80

?: 60 to 70

×: 60 or less

(3) scratch resistance

The pencil hardness was measured in order to evaluate the scratch resistance, and the pencil hardness was measured according to JIS K5600-5-4KS. Here, the pencil hardness is measured sequentially from 9B to 9H, and the closer to 9B the hardness is, the closer to 9H the harder the hardness.

F ↑: Excellent scratch resistance

B ↓: scratch resistance

◎: HB or more

○: B or more to F or less

DELTA: 4B or more to 2B or less

×: 5 B or less

(4) Corrosion resistance

The initial wetness of the coated specimens was evaluated by continuous spraying of 5% saline at 35 ° C and 95% humidity. The evaluation results were evaluated in the following manner.

◎: No more than 480 hours.

◯: Initial screening after 240 hours.

△: Initial call after 120 hours.

×: Initial call before 72 hours.

(5) Bending property

The surface of the coated specimen was bent by 180 °, then inserted into a vise and tightened to a flat surface. (0, 1, 2, 3T-Bending). A scotch tape was attached to the curved coating film, and when the coating film was peeled off, the state of peeling off the tape was evaluated.

◎: 0T, 1T, 2T, 3T No peeling.

◯: Initial screening after 240 hours.

△: Initial call after 120 hours.

×: Initial call before 72 hours.

(6) Lubrication

The lubricity was measured using a drag bead friction tester (load 1,000 kgf, speed 1,000 mm / min, distance 100 mm).

?: Friction coefficient less than 0.15

?: Friction coefficient 0.15 or more and less than 0.30

X: Friction coefficient 0.30 or more

(7) Adhesiveness

The coated specimens were cut with a cutter so as to have a width of 1 mm and a length of 1 mm to prepare 100 pieces, and 3M tape was attached and then peeled off to evaluate the adhesion of the coating. The evaluation results were evaluated in the following manner.

◎: No abnormality.

○: 10 or less eliminated.

△: Within 50 pieces.

×: Completely eliminated.

(8) Conductivity

The coated specimens were cut to a size of 30 cm x 30 cm in width and length to prepare specimens. The surface resistances of the specimens were measured five times using Loresta-GP (Mitsubishi Corp.) Respectively.

◎: When the reference resistance value is less than 0.1mΩ four times or more.

×: When the reference resistance value is less than 4 times, 0.1mΩ or less.

[Review results]

 The inventive and comparative examples have the greatest difference in the presence or absence of graphene oxide modified with acrylate.

The results of the physical properties test for each of the inventive and comparative examples are shown in Table 2. In the case of the inventive example, it exhibits excellent properties in appearance, gloss, scratch resistance, corrosion resistance, bending property, lubricity, adhesion and conductivity.

However, in the case of the comparative example, all of the gloss, the scratch resistance, the bending property, the lubricity, and the conductivity are inferior or exhibit an average property.

This means that the graphene modified graphene contained in the photocuring reaction was included in the photocuring reaction and thus the various properties were improved compared to the conventional UV coated steel sheet. .

Claims (17)

Acrylate modified graphene grains, oligomers, monomers, and photoinitiators. The method according to claim 1,
Wherein the graft coating composition comprises 1 to 50% by weight of the acrylate-modified graft oxide, 10 to 80% by weight of the oligomer, 10 to 80% by weight of the monomer, and 0.1 to 30% . The method according to claim 1,
Wherein the acrylate is one or more of a monofunctional acrylic monomer, a bifunctional acrylic monomer, and a polyfunctional acrylic monomer. The method according to claim 1,
Wherein the oligomer is selected from the group consisting of epoxy acrylate, urethane-based modified epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, acrylic acrylate, silicone acrylate, melamine acrylate, acrylic acrylate, polythiol acrylate derivatives, Wherein the polyglycolic acid is a mixture of at least one selected from the group consisting of acetal acrylates. The method according to claim 1,
Wherein the monomer is a mixture of one or more of a monofunctional monomer, a bifunctional monomer and a polyfunctional monomer. The method according to claim 1,
Wherein the monomer comprises 5-40 wt% monofunctional monomer and 5-30 wt% difunctional monomer. The method according to claim 1,
Wherein the photoinitiator is a benzophenone, diphenoxycibenzophenone, anthraquinone, xanthone, thioxanthone, or benzyl group. The method according to claim 1,
Wherein the composition further comprises at least one additive selected from the group consisting of a defoaming agent, a leveling agent, an adhesion promoter, a stabilizer, an antioxidant, an antistatic agent, a light absorber, a thermosetting agent, and a silane coupling agent. Preparing graphene oxide;
Replacing the functional group of the oxidized graphene with an acrylate to form an oxidized graphene modified with an acrylate;
And mixing the oligomer, monomer, and photoinitiator with the acrylate-modified oxide graphene. 10. The method of claim 9,
Wherein the functional group of the graphene oxide is a hydroxyl group, a carbonyl group, a carboxyl group, or an amine group. 10. The method of claim 9,
The step of making the grafted oxide grafted with acrylate
(a) dissolving graphene oxide in an organic solvent;
(b) mixing and reacting a compound containing a functional group capable of reacting with the functional group of the graphene oxide; And
(c) blocking with an alkyl acrylate. 10. The method of claim 9,
Wherein the step of making the oxidized graphene modified with acrylate is carried out at a temperature of 30 to 50 ° C. 12. The method of claim 11,
The compound containing a functional group capable of reacting with the functional group of the graphene oxide is a compound having an isocyanate group, an alkoxy group or a carboxyl group; A compound containing a halogen atom; And cyclic anhydrides, wherein the compound is at least one compound selected from the group consisting of a cyclic anhydride and a cyclic anhydride. 12. The method of claim 11,
Wherein the graphene oxide and the compound containing a functional group capable of reacting with the functional group of the graphene oxide are mixed in a molar ratio of 1: 2 to 2.1. Base steel sheet; And
A graphene-coated steel sheet comprising a coated layer comprising a cured product of the coating composition of any one of claims 1 to 8 on said backing steel sheet. 16. The method of claim 15,
The base steel sheet includes a cold-rolled steel sheet; galvanized steel; Galvanized electroplated steel sheet; Hot - dip galvanized steel; Aluminum-plated steel sheet; A coated steel sheet containing cobalt, molybdenum, tungsten, nickel, titanium, aluminum, manganese, iron magnesium, tin, copper or a mixture thereof; An aluminum alloy plate to which silicon, copper, magnesium, iron, manganese, titanium, zinc or a mixture thereof is added; Galvanized steel plates coated with phosphate; Or a hot-rolled steel sheet. 16. The method of claim 15,
Wherein the thickness of the coating layer is 0.5 to 20 占 퐉.