KR100774957B1 - Waterborne urethane acrylic hybride paint for metal coating and method of manufacturing coating layer using the same - Google Patents

Abstract

A water-dispersible urethane acryl hybrid coating agent for coating metals is provided to avoid the use of an excessive amount of surfactant, to form a coating film having a more dense structure and exhibiting excellent weather resistance and hardness, and to prevent environmental pollution. A water-dispersible urethane acryl hybrid coating agent for coating metals comprises: 38-60 wt% of a water soluble urethane acryl hybrid resin; 1-3 wt% of additives including a defoaming agent, wetting agent and anti-corrosive agent; and the balance amount of water, wherein the water soluble urethane acryl hybrid resin is obtained by polymerizing 40-80 parts by weight of a water soluble urethane dispersion and 30-40 parts by weight of acrylic monomers containing acetoacetoxy monomers in the presence of an acrylic reaction initiator.

Description

Waterborne Urethane Acrylic Hybride paint For Metal Coating and method of manufacturing coating layer using the same}

The present invention relates to a water-dispersed urethane acrylic hybrid paint for metal coating and a method for forming a coating film using the same, wherein the water-dispersed coating for metal coating is coated on a steel sheet having a plating layer composed of a mixture of zinc, nickel, aluminum, and silica or a single component. It relates to a urethane acrylic hybrid paint and a coating film forming method using the same.

Steel sheets having a plated layer composed of a mixture of zinc, nickel, aluminum, and silica or a single component are plated in a coil state at a steel company to maintain corrosion resistance and a luxurious appearance that are much better than those of ordinary cold and hot rolled steel sheets. By the way, the color of the steel sheet is very high in the value of the product due to the high whiteness and beautiful appearance of zinc, but the disadvantage is that the contamination caused by fingerprints is very reliably noticeable due to the roughness of zinc particles, resulting in the spread of corrosion. there is a problem.

Accordingly, in order to improve the workability, corrosion resistance, and fingerprint resistance, the surface of metals such as zinc alloy coated steel sheet or aluminum alloy steel sheet is coated with organic resin such as acrylic emulsion, water soluble epoxy, water dispersible urethane, etc. A thin film having a thickness of about 2 μm is formed.

That is, after electrochemical plating or molten plating such as zinc plating or zinc alloy plating is performed, a coating treatment using ethylene acetate copolymer resin or a coating method using epoxy resin is applied as a kind of coating treatment. have. However, ethylene acetate copolymer and epoxy resin cause deterioration and discoloration in harsh external environment such as heat, ultraviolet ray, acid rain, etc., thereby degrading the value of the product and deteriorating various properties required.

Acryl emulsion resin has been applied as a method to solve these problems, but due to the lack of basic corrosion resistance of the resin is often dependent on chromium and has a problem of high dependence on the styrene monomer which may be discolored. Therefore, in order to improve the defects of the physical properties obtained by the method of treating the ethylene acetate copolymer resin, epoxy resin, emulsion resin as described above, the present applicant for the plated steel sheet in Korea Patent Publication No. 2001-0088909 An emulsion resin composition has been disclosed. However, the emulsion resin was used to use a urethane acrylic paint by simply mixing with the urethane resin. Such paints have excellent physical properties in terms of weather resistance and solvent resistance, but are poor in storage properties and have disadvantages in physical properties such as water resistance and chemical resistance in thin film coatings due to the excessive surfactant contained in the emulsion resin.

In addition, since there is no physical and chemical bond between the emulsion resin and the urethane resin, there are advantages that each resin has, but disadvantages also increase.

Accordingly, an object of the present invention is to postcure the urethane and acryl resins in the post-curing reaction type, which is induced in the drying process by heat rather than physically, in order to improve the above problems. It is to provide a paint comprising a urethane acry hybrid resin capable of forming a copolymer by a chemical bond of.

In addition, another object of the present invention is to provide a method of forming a coating film using a coating material containing a urethane acrylic hybrid resin.

Water-dispersed urethane Acrylic hybrid paint for metal coating according to an embodiment of the present invention for achieving the above object is 38 to 60% by weight of water-soluble urethane Acrylic hybrid resin, and 1 to 3 weight of additives including antifoaming agent, wetting agent, rust inhibitor Contains% and extra water. In particular, the water-soluble urethane acrylic hybrid resin is characterized in that formed by reacting 40 to 70 parts by weight of the water-soluble urethane dispersion and 30 to 40 parts by weight of the acrylic monomer containing acetoacetoxy monomer in the presence of an aric reaction initiator.

As an example, the water-soluble urethane dispersion has an acid value of 10 to 50, an average diameter of 10 to 1000 nm, at least one selected from the group consisting of N-methylpyrrolidone, dimethylformamide and acetone. The water-soluble solvent comprises 1% to 20% by weight of the total water-soluble urethane dispersion resin, and has a molecular weight of 40000 to 200000.

In order to form the water-dispersed urethane acrylic hybrid coating film for metal coating according to an embodiment of the present invention for achieving the above another object, the acrylic monomer 30 containing 40 to 70 parts by weight of water-soluble urethane dispersion and acetoacetoxy monomer 30 38 to 60 parts by weight of a water-soluble urethane acryl hybrid resin, which is formed by polymerization and co-polymerizes upon thermal curing, 1 to 3% by weight of an additive including an antifoaming agent, a humectant and a rust preventive agent, and a metal containing excess water. A water-dispersed urethane acryl hybrid paint for coating is applied to the surface of the plated steel sheet. Thereafter, the coating material coated on the plated steel sheet is thermally cured. As a result, the paint is formed of a urethane acrylic hybrid coating film in which a copolymerization reaction of the functional group of the urethane domain contained in the water-dispersed urethane acrylic hybrid resin of the paint and the acetoacetoxy monomer of the acrylic domain is induced.

In order to prepare a water-dispersed urethane acrylic hybrid coating material for metal coating according to an embodiment of the present invention for achieving the above-mentioned other objects 30 to 70 parts by weight of the acrylic monomer containing a water-soluble urethane dispersion and acetoacetoxy monomer 30 to 40 parts by weight of a water-soluble urethane acryl hybrid resin formed by polymerization in the presence of an aric reaction initiator is prepared. Then, 1 to 3% by weight of an additive including an antifoaming agent, a humectant, and a rust preventive agent is mixed with 38 to 60% by weight of the water-soluble urethane acryl hybrid resin and excess water. As a result, a water-dispersed urethane acryl hybrid coating for metal coating is produced.

When the coating for metal coating containing the water-soluble urethane acryl hybrid resin described above is coated on a metal steel sheet and subjected to a drying process by heat, a copolymerization reaction of the functional group of the urethane domain and the acetoacetoxy monomer of the acryl domain in the resin is carried out. It is induced to form a coating film having excellent physical properties. That is, the paint has the characteristics of having a quick drying and excellent weather resistance, chemical resistance of urethane and acryl properties to improve the hardness at the same time.

Hereinafter, the water-dispersed urethane acrylic hybrid paint for metal coating, a method for preparing the same, and a method for forming a coating film using the paint according to preferred embodiments of the present invention will be described in detail, but the present invention is not limited to the following examples. It may be implemented in the form. In addition, the weight percent and weight portion may be used interchangeably and the embodiments introduced herein are provided to make the disclosure more complete and to fully convey the spirit and features of the invention to those skilled in the art.

Water Dispersed Urethane Acric Hybrid Paint and Manufacturing Method

The urethane acrylic hybrid paint for metal coating of the present invention is dense by inducing a copolymerization reaction between the functional group of the urethane domain and the acetoacetoxy monomer of the acrylic domain included in the water-dispersed urethane acryl hybrid resin in the heat drying process for forming a subsequent coating film. It is a paint which can form the coating film of tissue. That is, it is a paint which can form the urethane acrylic hybrid coating film which has a physical chemical bond between urethane and an acryl.

The paint has a composition comprising an additive including water-soluble urethane acrylic hybrid resin, antifoaming agent, wetting agent, rust inhibitor and water, specifically 38 to 60% by weight of water-soluble urethane arc hybrid hybrid resin and an antifoaming agent, wetting agent, anti-rust additive 1 To 3% by weight and excess water.

The water-soluble urethane acrylic hybrid resin includes an acrylic monomer including a water-soluble urethane dispersion and an acetoacetoxy acrylate monomer. The water soluble urethane dispersion is a well known material. Most of them have carboxylic acid in the polymer, and polyols are divided into polyester, polyether and acryl polyols.

The water-soluble urethane dispersion applied to the water-soluble urethane acrylic hybrid resin includes 40 to 70 parts by weight based on the total weight of the urethane acrylic hybrid resin solids. If it is less than 40 parts by weight, difficulties in stabilization of the acrylic monomer mixed in the urethane dispersion resin may occur, resulting in a problem in that physical properties such as elasticity and chemical resistance of the urethane are weakened. When it exceeds 70 parts by weight, the production price of the urethane acryl hybrid resin is high, which leads to poor commercial viability. Therefore, the amount of the water-soluble urethane dispersion is 40 to 70, preferably 45 to 65 parts by weight.

At this time, the water-soluble urethane dispersion applied has an acid value of 10-50, and contains a water-soluble solvent. If the acid value of the urethane dispersion is less than 10, water solubility is difficult, and if it exceeds 50, the water resistance becomes poor. Therefore, the water-soluble urethane dispersion has an acid value of 10 to 50, preferably has an acid value of 20 to 40.

In addition, if the average diameter of the water-soluble urethane dispersion particles is less than 10nm may be excellent in the stability of the acrylic monomer, but the problem of reducing the chemical resistance of the urethane occurs, if the exceeding 1000nm problem of the stability of the acrylic monomer is inferior This is brought about. Therefore, the average diameter of the particles has about 10 to 1000 nm, preferably 100 to 500 nm.

The solvent used in the water-soluble urethane dispersion is preferably to use a water-soluble solvent that can facilitate the reaction of the isocyanate group and the polyol and control the phase change of the urethane resin. N-methylpyrrolidone, dimethylformamide, acetone, etc. are mentioned as an example of the said water-soluble solvent. These can be used individually or in mixture of 2 or more. When the content of the water-soluble solvent contained in the water-soluble urethane dispersion is less than 1% by weight of the total weight of the water-soluble urethane dispersion, it is difficult to stabilize the acrylic monomer into the urethane dispersion, and when it exceeds 20% by weight, the acrylic monomer is It is difficult to hybridize between an acrylic monomer and a urethane dispersion, which swell during the reaction and have a high viscosity. Therefore, the solvent contains 1 to 20% by weight of the total weight of the water-soluble urethane dispersion, preferably 4 to 15% by weight.

 When the molecular weight of the water-soluble urethane dispersion is 40,000 or less, a problem of low chemical resistance and water resistance, which are excellent basic characteristics of the urethane resin, is caused. When the molecular weight is 200,000 or more, a problem occurs that the acrylic monomer absorbs and swells rather than stabilizes. do. Therefore, the molecular weight of the water-soluble urethane dispersion is 40000 to 200,000, preferably 80,000 to 150,000.

As an example of the said water-soluble urethane dispersion resin, Dipia Co., Ltd. urethane dispersion (solid content 34%, acid value 20 or less, molecular weight 70000, N-methylpyrrolidone content 12%), Alberdink Boley (Germany) U series, Takelac W series of Mitzui Takeda Chemical Co., Ltd., NeoRez series of Avecia, USA, Hyrex series of Korea Gwanggwang Chemical, etc. can be used alone or in combination of two or more.

The water-soluble urethane acrylic hybrid resin includes an acrylic monomer. The acryl-based monomer is 30 to 60 parts by weight based on the total weight of the solid content of the urethane acrylic hybrid resin. If the content of the acrylic monomer is less than 30 parts by weight, the amount of the urethane dispersion is relatively large, the price competitiveness is low, and when the content of more than 60 parts by weight, the reaction stability of the acrylic monomer in the water-soluble urethane dispersion is reduced. do.

 As an example of the said acryl-type monomer, an acrylate monomer, an acetoacetoxy monomer, an acrylamide monomer, etc. are mentioned. These acrylic monomers essentially include the acetoacetoxy monomer. In addition, the acrylic monomer may further include a monomer including a separate crosslinkable functional group for crosslinking with the curing agent after the resin is prepared.

Examples of the acrylate monomer included in the acrylic monomers include methyl acrylate, ethyl acrylate, ethyl acrylate, isopropyl acrylate, normal butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, Isopropyl methacrylate, normal butyl methacrylate, normal hexyl methacrylate, etc. are mentioned.

As an example of the acryl monomer which has a functional group for crosslinking contained in the said acryl-type monomer, 2-hardy hydroxy methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, etc. are mentioned. Examples of the amide monomer contained in the acryl-based monomers are acrylamide, methacrylamide, N-methylacrylamide, N-octylacrylamide, N-methylolacrylamide, N, N-dimethylaminomethylacrylamide, N, N- Dimethyl aminopropyl methacrylamide, diacetone amide, etc. are mentioned.

Examples of the acetoacetoxy monomers include acetoacetoxyethyl acrylate, acetoacetoxyethyl methacrylate, acetoacetoxypropyl acrylate, acetoacetoxypropyl methacrylate, diacetoacetoxyethyl acrylate and diacetoacetoxyethyl Methacrylate, diacetoacetoxypropyl acrylate, diacetoacetoxypropyl methacrylate, vinyl acetoacetate, vinyl diacetoacetate, allyl acetoacetate, allyl diacetoacetate, and the like.

In preparing the water-soluble urethane aric hybrid resin, the aric reaction initiator and the catalyst may be used. The acryl reaction initiator is used in an amount of 0.1 to 5 parts by weight relative to the solid content of the acrylic monomer. When the amount of the acryl reaction initiator is less than 0.1 part by weight, the reaction of the acrylic monomer does not proceed, and when the amount is more than 5% by weight, a problem of sludge due to rapid reaction is caused.

Examples of the aric reaction initiators include potassium peroxydisulfate, ammonium peroxydisulfate, dibenzoyl peroxide, lauryl peroxide, dietary butyl peroxide, 2,2-azobisisobutylonitrile, t-butyl peroxide, t -Butyl hydroperoxide, benzoyl peroxide, sodium formaldehyde sulfoxylate, etc. are mentioned. Examples of the aric reaction catalyst include iron sulfate heptahydrate, iron chloride cupric chloride, cobalt acetate, cobalt sulfate, and mixtures thereof.

As an example, in order to prepare the water-soluble urethane acrylic hybrid resin, first, the acrylic monomer is slowly added at 30 to 60 parts by weight at 40 to 70 parts by weight of the water-soluble urethane dispersion at low temperature. Allow to stabilize sufficiently. Subsequently, by raising the temperature sequentially, the water-soluble urethane dispersion and the acrylic monomer are polymerized to prepare the water-soluble urethane acrylic hybrid resin. In this case, the polymerization is preferably carried out in the presence of the aric reaction initiator and the catalyst.

As another example, in order to prepare the water-soluble urethane acrylic hybrid resin, a part of the acryl-based monomer is first stabilized at 40 to 70 parts by weight of the water-soluble urethane dispersion at low temperature. Subsequently, the temperature is raised, and the remaining acrylic monomer is added dropwise at about 40 to 60 ° C and stabilized again. Thereafter, the temperature is sequentially increased to polymerize the water-soluble urethane dispersion and the acrylic monomer to prepare the water-soluble urethane aric hybrid resin. In this case, the polymerization is preferably carried out in the presence of the aric reaction initiator and the catalyst.

The water-dispersed urethane acrylic hybrid paint for metal coating of the present invention is an additive 1-3 containing 3% by weight of an antifoaming agent, a humectant, a rust preventive agent, and water 39 to 59 in 38 to 60% by weight of the water-soluble urethane aric hybrid resin prepared by the above-described method. It can be prepared by mixing the weight percent.

When the content of the water-soluble urethane acryl hybrid resin contained in the paint is less than 38% by weight of the total weight of the paint, the workability of the paint is lowered due to the low viscosity, and when the content exceeds 60% by weight, the paint workability is due to the high viscosity. The problem of being lowered is brought about. Thus, the paint comprises 38 to 60% by weight of the water-soluble urethane acryl hybrid resin, and preferably contains 42 to 55% by weight.

The paint is difficult to form a coating film having the properties to be obtained in the present invention when the content of an additive including an antifoaming agent, a humectant, a rust preventive agent is less than 1% by weight or more than 3% by weight. Therefore, the paint contains 1 to 3% by weight of the additive including the antifoaming agent, the humectant, and the rust preventive agent, preferably 1.5 to 2% by weight.

When the content of water contained in the paint is less than 39% by weight or more than 59% by weight, the workability of the paint is lowered. Thus, the paint comprises 39 to 59% by weight of the water, preferably 45 to 55% by weight.

The coating material for metal coating of the present invention comprising the above-mentioned water-soluble urethane acryl hybrid resin, when the drying process by heat after coating the metal steel sheet, the air of the functional group of the urethane domain contained in the resin and the acetoacetoxy monomer of the acrylic domain The coalescence reaction can be induced to form a coating film having excellent physical properties. That is, the paint may have a fast drying and excellent weather resistance, chemical resistance of the urethane and the acryl properties to improve the hardness at the same time.

Urethane Acrylic Hybrid Coating Film Forming Method

In order to form a urethane acrylic hybrid coating film, first, a water-soluble urethane acry hybrid resin 38 to 60% by weight, 1 to 3% by weight of an additive including an antifoaming agent, a humectant, and a cleaning agent, and a water-dispersed urethane aric for metal coating containing excess water Prepare a hybrid paint.

The water-soluble urethane acrylic hybrid resin included in the paint is formed by polymerizing 40 to 70 parts by weight of the water-soluble urethane dispersion and 30 to 40 parts by weight of the acrylic monomer including acetoacetoxy monomer, and has a property of co-polymerizing upon thermal curing.

The composition, composition ratio, and preparation method thereof of the water-soluble urethane acrylic hybrid resin are omitted in order to avoid duplication because they have been described in detail above. In addition, since the components constituting the paint and the composition ratio thereof are also described in detail above, they are omitted to avoid duplication.

Subsequently, the water-dispersed urethane acryl hybrid coating material for metal coating is coated on the surface of the plated steel sheet. The paint may be coated to a thickness of about 1 to 10um on the coated steel sheet using a spray.

Subsequently, the paint coated on the plated steel sheet is thermally dried at a temperature of about 80 to 130 ° C. As a result, a urethane acrylic hybrid coating film is formed on the plated steel sheet to induce a copolymerization reaction of the functional group of the urethane domain contained in the water-dispersed urethane acrylic hybrid resin of the paint and the acetoacetoxy monomer of the acrylic domain. The urethane acrylic hybrid coating film has excellent weather resistance and chemical resistance of urethane and acryl to improve hardness at the same time.

  Hereinafter, the present invention will be described in detail through specific examples. However, it is a matter of course that the present invention is not limited only to the following examples.

Example

457 g of a water-soluble urethane Acrylic hybrid resin (Note 1) copolymerized with a urethane domain acrylic domain in the subsequent drying process according to the mixing ratio of Table 1 and the antifoaming agent (BYK-024, BYK Chemie) 1g, wetting agent (BYK-346 , BYK Chemie) 2g, rust preventive (LF rust M-PSN, Kikuchi Color Co., Ltd.) 15g and water containing 525g was prepared.

Comparative example

According to the blending ratio of Table 1, 457g of the urethane acryl hybrid resin (Note 2) of the network structure, antifoaming agent (BYK-024, BYK Chemie) 1g, wetting agent (BYK-346, BYK Chemie) 2g, rust preventive agent (LF rust-preventing M-PSN , Kikuchi Color Co., Ltd.) 15 g and water 525 g were prepared.

Table 1 Paint Preparation

 Example (g) Comparative Example (g) Resin Note 1 457 Resin Note 2 457 Antifoam One One Humectant 2 2 Rust preventive 15 15 water 525 525 Sum 1000 1000

Paint and Film Evaluation

In order to find out the characteristics of the paints of the Examples and Comparative Examples having the composition of Table 1, the storage properties of the paints were evaluated. Then, the coatings of the above Examples and Comparative Examples were coated with a thickness of 2 μm on a degreased galvanized steel sheet having a size of 70 ㅧ 150 후 0.5mm, and then the specimen was baked at 100 ° C. to prepare a specimen (treated steel sheet). The physical properties of the coating film were evaluated. The results are shown in Table 2 below.

Table 2 Coating Evaluation

 Example Comparative example varnish Zhejiang ◎ ◎ Coating Exterior ◎ ◎ Corrosion resistance ◎ ○ Heat resistance ○ △

From the above Table 2, in the case of using the urethane acrylic hybrid paint having the composition of the embodiment, the storage property of the paint is excellent and there is no phase separation, and the coating film formed from the paint is also compared with the coating film formed from the coating material of the comparative example in terms of appearance, corrosion resistance and heat resistance. It was found to exhibit excellent effects.

Hereinafter, the storage property of the paint and the physical property evaluation method of the coating film are as follows.

Paintability Test of Paint

The coated example is sealed and stored at 50 ° C. for 7 days and then evaluated by measuring the change in viscosity at 25 ° C. with Ford Cup # 4.

(◎: no abnormality, ○: viscosity rises for 5 seconds, △: viscosity rises for 10 seconds, X: cannot be measured)

Appearance test of coating

Evaluate the appearance of the painted specimens, with no foreign matter and no unpainted area.

(◎: No abnormality, ○: Tee slightly, △: Cratering, X: Unpainted)

Corrosion Resistance Test of Coating Film

The initial specimen was evaluated by spraying continuously 5% saline at 35 ° C. and 95% humidity.

(◎: No more than 72 hours, ○: Initial call after 48 hours △: Initial call after 24 hours, X: Initial call before 24 hours)

Heat resistance test of coating film

After the coated specimen is left for 20 minutes at an ambient temperature of 240 ° C., the discoloration or loss of the coating film is evaluated.

(◎: No abnormality, ○: ΔE = 5 or less, ΔΔE = 10 or less, X: complete deterioration)

As described above, when the coating for the metal coating containing the water-soluble urethane Acrylic hybrid resin is coated on a metal sheet and then subjected to a drying process by heat, the functional group of the urethane domain contained in the resin and the acetoacetoxy group of the acryl domain The copolymer reaction may be induced to form a coating film having a denser structure. That is, the paint has the characteristics of having a quick drying and excellent weather resistance, chemical resistance of urethane and acryl properties to improve the hardness at the same time. In addition, the paint has the advantage of reducing the energy saving problem, environmental pollution problem, work hygiene stability problem and fire risk because the solvent uses water as the main component.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified without departing from the spirit and scope of the invention described in the claims below. And can be changed.

Claims (7)

38 to 60% by weight of a water-soluble urethane acryl hybrid resin; 1-3 wt% of an additive including an antifoaming agent, a humectant, and a rust preventive agent; Include extra water, The water-soluble urethane acrylic hybrid resin A water-dispersed urethane acrylic hybrid coating for metal coating, wherein 40 to 70 parts by weight of a water-soluble urethane dispersion and 30 to 40 parts by weight of an acrylic monomer including an acetoacetoxy monomer are polymerized in the presence of an aric reaction initiator. The water-dispersed urethane acrylic hybrid paint of claim 1, wherein the water-soluble urethane dispersion has an acid value of 10 to 50 and a particle size of 10 to 1000 nm in average diameter. The method of claim 1, wherein the water-soluble urethane dispersion is 1 to 20% by weight of the total water-soluble urethane dispersion resin at least one water-soluble solvent selected from the group consisting of N-methylpyrrolidone, dimethylformamide and acetone It contains, and has a molecular weight of 40000-200000, The water dispersion urethane aric hybrid coating material for metal coatings characterized by the above-mentioned. The method of claim 1, wherein the acetoacetoxy monomer is acetoacetoxyethyl acrylate, acetoacetoxyethyl methacrylate, acetoacetoxy propyl acrylate, aceto acetoxy propyl methacrylate, diaceto acetoxy ethyl acrylate, At least one selected from the group consisting of diacetoacetoxyethyl methacrylate, diacetoacetoxypropyl acrylate, diacetoacetoxypropyl methacrylate, vinyl acetoacetate, vinyl diacetoacetate, allyl acetoacetate and allyl diacetoacetate Water-dispersed urethane acrylic hybrid paint for metal coating comprising a. 40 to 70 parts by weight of a water-soluble urethane dispersion and 30 to 40 parts by weight of an acryl-based monomer including an acetoacetoxy monomer, and 38 to 60% by weight of a water-soluble urethane acrylic hybrid resin which is co-polymerized upon thermal curing, and an antifoaming agent and a wetting agent. Coating a surface of the plated steel sheet with a water-dispersed urethane acryl hybrid paint for metal coating containing 1 to 3% by weight of an additive including a rust preventive agent and excess water; And Thermally curing the paint coated on the plated steel sheet to form a urethane acrylic hybrid coating film in which a copolymerization reaction between a functional group of the urethane domain included in the water-dispersed urethane acryl hybrid resin of the paint group and the acetoacetoxy monomer of the acrylic domain is induced. Coating film formation method containing. The method of claim 5, wherein the water-soluble urethane acrylic hybrid resin Adding 30 to 60 parts by weight of an acryl monomer including acetoacetoxy monomer to 40 to 70 parts by weight of a water-soluble urethane dispersion; Stabilizing an acrylic monomer in the water-soluble urethane dispersion; And And coating the water-soluble urethane dispersion and the stabilized acrylic monomer in the presence of an aric reaction initiator. Preparing a water-soluble urethane acryl hybrid resin; And 38 to 60% by weight of the water-soluble urethane Acrylic hybrid resin, including an anti-foaming agent, wetting agent, 1 to 3% by weight of an additive including a rust preventive agent, and the step of mixing excess water, The water-soluble urethane acrylic hybrid resin is water-soluble urethane dispersion 40 to 70 parts by weight of the acrylic monomer containing acetoacetoxy monomer and 30 to 40 parts by weight of the acrylic coating for water dispersing urethane acryl, characterized in that formed by polymerization in the presence of an acryl reaction initiator. Method for producing a hybrid paint.