KR101816398B1 - Multilayered coating film for automobile and manufacturing method thereof - Google Patents

Abstract

A base coat layer comprises a first base layer comprising a black pigment and a first base layer comprising a glass flake and a second base layer on the first base layer, And a second base layer including a first base layer and a second base layer.
The coating film according to an embodiment of the present invention includes a double-layered base coat layer including a first base layer including a black pigment and a second base layer including a glass flake on the first base layer , It is possible to further improve the feeling of the particle and the layer separation while satisfying the excellent blackness.

Description

TECHNICAL FIELD [0001] The present invention relates to a multi-layer coating film for automobiles,

More particularly, the present invention relates to a multi-layer coating film for automobiles, and more particularly to a multi-layer coating film for automobiles, which comprises a first base layer containing a black pigment and a glass flake on the first base layer, A second base layer, and a method of manufacturing the same.

A typical automotive exterior coating film is composed of a multi-layer coating film and is generally composed of a middle layer, a base coat layer and a clear coat layer as shown in Fig.

In the automotive market, black color accounts for more than 20% of the market share. In the automotive market, black color is pure black with no particles and 2 blacks with a particle feel.

At present, carbon black is widely used as a pigment which realizes black color of the base coat layer of an automobile paint.

Carbon black is a substance produced when fossil fuels such as petroleum or coal or wood burns incompletely and absorbs heat in the air and light having a wavelength ranging from the ultraviolet region of the sun to the far infrared region, that is, the sun infrared ray and heat radiation .

In general, the solar absorption rate of a black pigment to which carbon black is applied is measured to be 95% or more. Because of this characteristic, the carbon black mixed in the automobile coating absorbs the infrared rays to cause the temperature of the coating to rise, and the increased coating film temperature can transfer heat to the inside of the car and the car, resulting in an increase in the temperature inside the car.

On the other hand, examples of the pigment that expresses the particle feel include mica (MICA) or aluminum flake, and the pigments can be mixed with a pure black pigment and added to give a particle feel.

That is, as shown in FIG. 2, a base coat layer is formed by mixing a pure black pigment and a pigment expressing the particle feeling on one surface of the intermediate layer to increase the feel of the particles, and a clear coat layer is coated on the base coat layer, A coating film can be formed. At this time, when the amount of the pigment expressing the graininess is large, the blackness is lowered and can be seen as a dark gray color, and if the amount of the pigment expressing the graininess is too small, the graininess may be lowered.

In addition, when a pigment that expresses a particle sensation is mixed with a pure black pigment and coating, the layer separation sensation of the coating film is inhibited and the coating film may appear thin, thereby deteriorating the quality of the automobile.

Therefore, it is necessary to develop a coating film for automobiles that includes a black color coating composition capable of improving the feeling of particles and the layer separation while maintaining an excellent blackness.

Korean Patent Publication No. 10-2015-0068842

A first object of the present invention is to solve the problems of the prior art as described above, and to provide a coating film which can further improve the sensation of granularity and layer separation while satisfying excellent blackness.

A second technical problem to be solved by the present invention is to provide a method for producing the coating film.

In order to solve the above problems, the present invention provides a multilayer coating film in which a middle layer, a base coat layer and a clear coat layer are sequentially formed, wherein the base coat layer comprises a first base layer including a black pigment, And a second base layer including a glass flake on the first base layer.

The present invention also provides a method for forming a base coating composition, comprising the steps of: forming a first base layer by coating a first base coating composition comprising a black pigment on the intermediate layer formed by coating the intermediate coating composition; Coating a second base coating composition comprising a glass flake on the first base layer to form a second base layer; And coating a clear coat paint composition on the second base layer to form a clear coat layer.

The coating film according to an embodiment of the present invention includes a double-layered base coat layer including a first base layer including a black pigment and a second base layer including a glass flake on the first base layer , It is possible to further improve the feeling of the particle and the layer separation while satisfying the excellent blackness.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description of the invention, It should not be construed as limited.
1 is a sectional view of a coating film of Comparative Example 1;
2 is a sectional view of a coating film of Comparative Example 2. Fig.
3 is a cross-sectional view of a coating film of Example 1 according to an embodiment of the present invention.
FIG. 4 is a schematic view showing the appearance of particles due to reflection of light of a coating film of Example 1 according to an embodiment of the present invention. FIG.
FIG. 5 is a schematic view showing the formation of a silane-decomposing layer on the side of light of Example 1 according to an embodiment of the present invention.
6 is a graph showing the change in blackness (MF) according to the content of carbon black contained in the coating film.
7 is a graph showing the change in blackness according to the content of the glass flakes in the examples of the present invention.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

The coating film of the present invention is a multilayer coating film in which a middle layer, a base coat layer, and a clear coat layer are sequentially formed, wherein the base coat layer comprises a first base layer including a black pigment and a glass flake and a second base layer including a glass flake.

The coating film according to an embodiment of the present invention includes a double-layered base coat layer including a first base layer including a black pigment and a second base layer including a glass flake on the first base layer , It is possible to further improve the feeling of the particle and the layer separation while satisfying the excellent blackness.

3 to 5, a coated layer according to an embodiment of the present invention includes a middle layer 10, a base coat layer 20, and a first base layer 20 as a base coat layer 20, 25 and a clearcoat layer 30 are sequentially laminated.

Specifically, the base coat layer 20, 25 according to an embodiment of the present invention includes a first base layer 20 including a black pigment.

The first base layer may be a pure black layer, and the black pigment included in the first base layer may include carbon black capable of exhibiting a pure black color without a graininess. The first base layer can realize excellent black color by including the black pigment.

Also, the first base layer is a layer to which the first base coating composition containing the black pigment is applied, wherein the first base coating composition comprises from 0.5 wt% to 10 wt% of a black pigment based on the total weight of the first base coating composition, 10 to 50% by weight of a polymer resin, 0.5 to 5% by weight of an acrylic additive, and 40 to 85% by weight of a solvent.

According to one embodiment of the present invention, when the first base coating composition having the above-mentioned content is obtained, an optimum workability can be secured, and a coating film having blackness and excellent physical properties can be obtained.

Specifically, the black pigment is preferably used in an amount of 0.5 to 6% by weight, more preferably 1 to 5.5% by weight, most preferably 1.2 to 2.4% by weight, based on the total weight of the first base coating composition. As shown in FIG.

In the first base coating composition, if the black pigment exceeds the above range, aggregation of the pigments may increase, which may be difficult to exhibit excellent blackness, and may also result in deterioration of particle feelability. On the other hand, when the black pigment is less than the above range, the blackness may decrease.

The thickness of the first base layer may be 7 to 12 占 퐉, preferably 7 to 10 占 퐉. If the thickness of the first base layer is too large, the granularity development may be deteriorated. If the thickness is too thin, the blackness may be reduced.

In addition, the base coat layer according to an embodiment of the present invention includes a second base layer 25 including a glass flake.

The second base layer may serve as a permeable layer to improve the sense of granularity and layer separation.

The coating film according to an embodiment of the present invention can separate the first base layer including the black pigment and the second base layer including the glass flake to improve the feel and feel of the layer while maintaining excellent blackness have.

The glass flake may have better light transmittance than Mica (MICA) or aluminum flake which expresses the particle feel. Layer base coat layer consisting of a first base layer comprising, for example, a black pigment and a second base layer comprising a mica or an aluminum flake, the glass flake, which is a constituent of the present invention relative to a mica or aluminum flake, So that more light can reach the pure black layer and thus blackness can be more advantageous for the expression.

4, a coating film according to an embodiment of the present invention includes a first base layer 20 and a clear coat layer 30, which are formed by placing a second base layer 25 including a glass flake between the first base layer 20 and the clearcoat layer 30, The light incident on the coating film can be further scattered, and the particle feel can be generated at the portion where the light is projected. In addition, the transmittance is improved to reduce the loss of light, and the black pigment particles included in the coating can be clearly seen as a magnifying glass, resulting in a sharper and deeper color of the coated film.

Further, as shown in FIG. 5, it is possible to develop a feeling of layer separation in which the black color appears to be distant when there is no light, and the quality of the vehicle can be improved by making the black color sharper and deeper.

In addition, the glass type of the glass flake can be used in either A glass, C glass or E glass. A glass is soda-lime glass, which contains more sodium than potassium and calcium dioxide. C glass or so-called chemical glass is resistant to acid and moisture corrosion. It usually contains zinc oxide and other oxides. E-glass or electric glass can be used in electrical applications, as the name suggests, and can be easily subjected to chemical damage, although very stable at high temperatures. C glass and A and E glasses have a wide range of chemical composition.

The glass flakes contained in the second base layer preferably have an average particle size of 2 to 50 탆, preferably 5 to 40 탆, more preferably 10 to 35 탆, and a thickness of 5 탆 or less, And may be a plate having a diameter of 0.5 to 4 탆.

In the coating film according to an embodiment of the present invention, the glass flakes may use, for example, TITANIA COAT RS1030 manufactured by NSG, having an average particle size of about 30 μm.

According to an embodiment of the present invention, it is preferable that the second base layer does not include carbon black. That is, since the glass flake of the present invention is separated from the black pigment, the coating film of the present invention can increase the effect of exhibiting the graininess and the effect of reducing the separation of the layer even in a small amount.

 Wherein the second base layer is a layer applied with a second base coating composition comprising the glass flake, wherein the second base coating composition comprises 0.05 to 5% by weight of glass flakes based on the total weight of the second base coating composition, 10 to 50% by weight of the polymer resin, 0.5 to 5% by weight of the acrylic additive, and 40 to 85% by weight of the solvent.

According to one embodiment of the present invention, when the second base coating composition having the above-mentioned content is obtained, optimum workability can be ensured and excellent particle feel and layer separation sensation effect can be achieved while maintaining excellent blackness have.

Specifically, the glass flake preferably comprises 0.05 to 3% by weight, more preferably 0.05 to 2% by weight, most preferably 0.05 to 0.17% by weight, based on the total weight of the second base coating composition, As shown in FIG.

In the second base coating composition, the blackness may be reduced when the glass flakes are in the above range, and when the glass flakes are less than the above range, the blackness may be favorable, but the coating film may be thin There may be a problem that the feeling of quality is separated.

In the coating film according to an embodiment of the present invention, the content ratio of black pigment to glass flake may be 1: 0.02 to 0.9 weight ratio, preferably 1: 0.025 to 0.85 weight ratio, , It is possible to achieve an optimal feeling of graininess and layer separation while maintaining the excellent blackness desired in the present invention.

The thickness of the second base layer may be 2 to 5 占 퐉, preferably 3 to 4 占 퐉. The coating layer according to an embodiment of the present invention has the second base layer in the thickness range, so that the light can reach the pure black layer of the first base layer and improve the sense of granularity and layer separation. If the thickness of the second base layer is too thick, the degree of blackness can be reduced. If the thickness is too thin, the granularity and layer separation can be deteriorated.

Meanwhile, in the coating film according to an embodiment of the present invention, the polymer resin, the acrylic additive and the solvent contained in the base coat layer, that is, the first base layer and the second base layer, Materials commonly used in the art can be used without limitation.

For example, the polymer resin may be any one selected from the group consisting of an acrylic resin, a polyester resin, and melamine formaldehyde, or a mixture of two or more thereof.

Specifically, the acrylic resin may be included as a main resin, and may be included in the first base coating composition and the second base coating composition in an amount of about 10% by weight to 20% by weight based on the total weight of the coating composition, respectively. If the acrylic resin is less than 10% by weight, physical properties of the coating film may be deteriorated. If the acrylic resin is more than 20% by weight, workability may be deteriorated by adding an excess amount of the polymer resin.

Further, the polyester resin is an auxiliary resin added to improve the smoothness and to enhance the adhesion to the intermediate layer, wherein the first base coating composition and the second base coating composition each contain about 3 wt% By weight to 8% by weight. If the amount of the polyester resin is less than 3% by weight, a problem of deterioration of adhesion with the intermediate layer may occur, and if it exceeds 8% by weight, physical properties of the coating film may be deteriorated.

On the other hand, the melamine formaldehyde can be used as a curing agent, and can be used as a substitute for a curing agent of a kind having an effect equal to or higher than that of melamine formaldehyde, or can be used in admixture with the melamine formaldehyde.

In addition, the melamine formaldehyde may be included in the first base coating composition and the second base coating composition, respectively, in an amount of about 2% to 6% by weight based on the total weight of the coating composition. When the content of the melamine formaldehyde is less than 2% by weight, the physical properties of the coating film may be deteriorated due to the lowering of the curing reactivity, and when it exceeds 6% by weight, the impact resistance may be lowered.

Meanwhile, the acrylic additive may be any one selected from the group consisting of an acrylic copolymer, a silicone-modified acrylic compound and an acrylic derivative, or a mixture of two or more thereof.

The acrylic copolymer may serve as a pinhole inhibitor added to prevent pinholes in the paint. Preferably, the first and second base coating compositions may contain 1 wt% to 2 wt% %. ≪ / RTI > If the amount of the acrylic copolymer is less than 1% by weight, the pinhole generation inhibiting performance may deteriorate, and if it exceeds 2% by weight, the quality may deteriorate in appearance.

The silicone-modified acrylic compound may serve as a surface conditioner for improving the smoothness of the coating material. Preferably, the first base coating composition and the second base coating composition may each contain 1 wt% to 2 wt% %. ≪ / RTI > If the amount of the silicone-modified acrylic compound is less than 1% by weight, the smoothness of the coating may be lowered. If the amount of the silicone-modified acrylic compound exceeds 2% by weight, the adhesion between the layers may be deteriorated.

The acrylic derivative may serve as a flow inhibitor for preventing the flow of the paint. Preferably, the first base coating composition and the second base coating composition each contain 0.1 to 1% by weight, based on the total weight of the coating composition, ≪ / RTI > If the acrylic derivative is less than 0.1% by weight, the anti-flow performance (SAG) of the paint may be lowered, and if it exceeds 1% by weight, the smoothness of the paint may decrease.

In addition, the solvent may serve to improve the workability of painting, and the kind thereof is not particularly limited, and various solvents conventionally used in the art can be used. Specifically, the solvent may be any one selected from the group consisting of water, an alcohol-based solvent and a glycol-based solvent, or a mixture of two or more thereof.

The solvent may include deionized water, distilled water, or pure water.

The alcohol-based solvent may be any one selected from the group consisting of ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, and glycerin, or a mixed alcohol of two or more thereof.

Examples of the glycol-based solvent include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol di Diethylene glycol dialkyl ethers such as ethyl ether, diethylene glycol dipropyl ether or diethylene glycol dibutyl ether, ethylene glycol alkyl ether acetates such as methyl cellosolve acetate or ethyl cellosolve acetate, or propylene glycol mono And alkylene glycol alkyl ether acetates such as methyl ether acetate, propylene glycol monoethyl ether acetate and propylene glycol monopropyl ether acetate, and mixtures of two or more of them may be used.

The content of the solvent may be used in the first base coating composition and the second base coating composition in an amount of 40 wt% to 85 wt%, preferably 57 wt% to 80 wt%, based on the total weight of the coating composition, respectively. If the content of the solvent is less than the above range, the viscosity of the coating composition may increase, and the workability of the coating composition may deteriorate. If the content of the solvent exceeds the above range, the viscosity of the coating composition may decrease.

According to an embodiment of the present invention, the solvent is added to the first basecoat composition and the second basecoat composition in an amount of 40 wt% to 50 wt% of distilled water, 7 wt% to 15 wt% of alcohol solvent, , And glycol solvent in an amount of 10% by weight to 15% by weight, the optimum workability and viscosity of the coating can be achieved.

The coating layer according to an embodiment of the present invention may be formed by sequentially forming the intermediate layer 10, the base coat layer 20, and the clear coat layer 30, as shown in FIGS.

In the coating layer according to an embodiment of the present invention, the intermediate layer 10 may impart smoothness, chipping resistance, and light diffusing property, and may include the first base layer 20 and the second base layer 25 The base coat layer of the double layer can impart color, layer separation feeling and particle feel to the automobile. Further, the clear coat layer 30 can impart smoothness, gloss, weather resistance, and durability.

Specifically, the intermediate layer 10 may serve to reflect infrared rays transmitted through the clear coat layer 30 and the base coat layers 20 and 25 in the present invention. The coating composition to be applied to the intermediate layer may be a mid-coat composition commonly used in the art, and each component can be used without any particular limitation by controlling the type and content thereof.

The intermediate coating composition may contain, for example, carbon black, which is a conventionally used pigment, and a rutile type oxidation pigment having a high refractive index may be used to enhance the reflection effect of the intermediate layer. The rutile type oxidative branch is used in an amount of 5 to 30% by weight, preferably 10 to 20% by weight, based on the total weight of the intermediate coating composition. Examples of products applicable as the oxidized pigment of the present invention include Ti-Pure R706, Ti-Pure R900 manufactured by DuPont, Kronos 1000 and Kronos 1001 manufactured by Kronos.

In addition, the clear coat layer 30 of the present invention protects the surface of the base coat film and can provide a durability such as an appearance effect such as smoothness or glossiness, weather resistance, water resistance, or chemical resistance. The clearcoat paint composition applied to the clearcoat layer of the present invention may be a clearcoat paint composition conventionally used in the art, and each component may be used without any particular limitation by controlling the kind and content thereof.

Further, according to the present invention, a brightener such as aluminum particles or mica particles can be further used to maximize the sunlight reflecting effect of the clear coat layer. The content thereof is used in an amount of 0.1 to 8% by weight, preferably 0.5 To 2% by weight is suitable.

Examples of products applicable as the brightening agent of the present invention include STAPA30, Hydrolan 2192 from Eckart, Sparkle Silver E2141 and E2992 from Silberline, and Iriodin 121 from Merck.

Meanwhile, the present invention can provide a method of manufacturing the coating film according to an embodiment.

According to an embodiment of the present invention, there is provided a method of manufacturing a coating film, comprising: coating a first base coating composition containing a black pigment on a center layer formed by coating a center coating composition to form a first base layer; Coating a second base coating composition comprising a glass flake on the first base layer to form a second base layer; And coating a clear coat paint composition on the second base layer to form a clear coat layer.

In addition, each of the layers may further include a step of coating and then drying the coating composition.

Specifically, the intermediate coating composition containing oxidized lipid, extender pigment, carbon black, luminous pigment, resin and solvent is first applied on the electrodeposited coating film so that the thickness of the dried coating film is 25 to 35 μm (coating condition: 20 ° C. relative Humidity of 80%, relative humidity of 25 DEG C of 70%, relative humidity of 28 DEG C of 60%) and then cured in a general oven at about 150 DEG C for about 30 minutes to form an intermediate layer. The first base coating composition was applied on the formed intermediate layer to a thickness of 7 to 12 占 퐉 (coating condition: 20 占 폚 relative humidity 80%, 25 占 폚 relative humidity 70%, 28 占 폚 relative humidity 60% Thereby forming a base layer. Then, the second base coating composition was coated on the first base layer to a thickness of 2 to 5 占 퐉 (coating condition: 20 占 폚 relative humidity 80%, 25 占 폚 relative humidity 70%, 28 占 폚 relative humidity 60% ) To form a second base layer. Then, after leaving for 1 to 5 minutes under normal temperature conditions, the clearcoat paint composition was coated (coating condition: 20 DEG C, relative humidity 80%, 25 DEG C, relative humidity 70%, 28 Lt; 0 > C and a relative humidity of 60%) and then cured in a general oven at 150 DEG C for about 30 minutes to form a multilayer coating film.

The coating method on each side is not particularly limited, but may be spin coating, roll coating, dip coating, spray coating, or the like.

The blackness of the coating film according to an embodiment of the present invention may be about 180 to 200 when the blackness is represented by the Mf value established by Lippok-Lohmer. Also, the SG may be 4 to 5 based on the numerical value defined in JIS Z8729 (1994) (Measuring equipment: BYK-MAC by BYK).

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.

Example

EXAMPLES The present invention will be further illustrated by the following examples and experimental examples, but the present invention is not limited by these examples and experimental examples.

<Preparation of the first coating film double layer comprising a base layer and second base layer>

Example  One :

&Lt; Preparation of first base coating composition >

As shown in the following Table 1, 1.8% by weight of carbon black, 16.2% by weight of acrylic main resin, 5.4% by weight of polyester auxiliary resin, 3.6% by weight of melamine formaldehyde curing agent, , 1.2% by weight of a silicone-modified acrylic as a surface modifier, 0.2% by weight of an acrylic derivative as a flow inhibitor, 47.2% by weight, 9.18% by weight and 13.4% by weight of a glycol- % Was stirred at room temperature for about 10 minutes at 500 rpm to obtain a first base coating composition.

&Lt; Preparation of second base coating composition >

As shown in the following Table 1, 0.12% by weight of glass flake, 15.4% by weight of acrylic main resin, 6.6% by weight of polyester auxiliary resin, 3.1% by weight of melamine formaldehyde curing agent, , 1.2% by weight of silicone-modified acrylic as a surface modifier, 0.2% by weight of an acrylic derivative as a flow inhibitor, 47.1% by weight, 11.18% by weight and 13.36% by weight of a glycol- % Was stirred at room temperature for about 10 minutes at 500 rpm to obtain a second base coating composition.

The first base coating composition was coated on an SPC steel plate with a zinc phosphate pretreated cation electrodeposition and a moderate coating to form a first base layer on a cured and dried specimen so as to have a thickness of about 7 μm by a spray gun Respectively. After about 1 to 3 minutes, the second base coating composition was coated on the first base coating layer to a thickness of about 3 μm to form a second base coating layer. After cooling to about 50 to 80 ° C (Flash off / on) After the clearcoat layer was formed by applying the clearcoat paint composition, it was allowed to stand at room temperature for about 10 minutes and thermally cured at about 150 ° C for 30 minutes to prepare a black base coat.

Example  2 to 7

The first base coating composition contains 2% by weight of carbon black, and the second base coating composition contains 0.01% by weight, 0.05% by weight, 0.09% by weight, 0.13% by weight, 0.17% by weight and 0.12% by weight % Was used instead of the base coat layer in Example 1, to obtain a coating film.

Comparative Example  1: Single layer including carbon black The base coat layer  Included Coating Production

<Preparation of Carbon Black Coating Composition>

As shown in the following Table 1, it was found that when 1.8% by weight of carbon black, 16.2% by weight of acrylic main resin, 5.4% by weight of polyester auxiliary resin, 3.6% by weight of melamine formaldehyde curing agent, , 1.2% by weight of a polymer, 1.2% by weight of a silicone-modified acrylic as a surface modifier, 0.2% by weight of an acrylic derivative as a flow inhibitor, 47.2% by weight, 9.18% by weight and 13.4% by weight of a distilled water, an alcohol- At 500 rpm for about 10 minutes to obtain a base coating composition.

The base coating composition was coated on a SPC steel plate with a zinc phosphate pretreated cation electrodeposition and a moderate coating to form a first base layer on a cured and dried specimen with a spray gun. After about 1 to 3 minutes, the clearcoat coating composition is applied by cooling at about 50 to 80 ° C (Flash off / on) to form a clearcoat layer, then left at room temperature for about 10 minutes, And then thermally cured for 30 minutes to prepare a black base coating film.

Comparative Example  2: Monolayer containing carbon black and MICA (particulate black pigment) The base coat layer  Included Coating Production

As shown in the following Table 1, a mixture of 1.2% by weight of carbon black and 0.4% by weight of MICA as a pigment, 15.8% by weight of main acrylic resin, 6.7% by weight of polyester auxiliary resin, 3.2% by weight of melamine formaldehyde curing agent, , 1.2% by weight of silicone-modified acrylic as a surface conditioner, 0.2% by weight of an acrylic derivative as a flow inhibitor, 46.4% by weight, 10.21% by weight and 13.14% by weight of a distilled water, an alcohol- And the mixture was stirred at 500 rpm for about 10 minutes to obtain a base coating composition.

A black base coating film was prepared in the same manner as in Comparative Example 1 except that the base coating composition prepared above was used.

The ingredients and contents of the raw materials added to the black base coating compositions of the above Examples and Comparative Examples are shown in Table 1 below.

Comparative Example  3: Bilayer  Coating Production

MICA was added as a pigment to the second base coating composition as a pigment in the first base coating composition and a first base coating composition and a second base coating composition containing the components and contents of the following Table 1 were prepared and used , A double-layered black base coating film was prepared in the same manner as in Example 1.

ingredient Comparative Example 1 Comparative Example 2 Example 1 The first base coating composition The second base coating composition Pigment Carbon black (% by weight) 1.8 1.2 1.8 - MICA (% by weight) - 0.4 - - Glass flakes (weight%)
NSG TITANIA COAT RS1030 - - - 0.12 Suzy Acrylic resin (% by weight) 16.2 15.8 16.2 15.4 Polyester resin (% by weight) 5.4 6.7 5.4 6.6 Melamine formaldehyde (curing agent) (% by weight) 3.6 3.2 3.6 3.1 additive Pinhole inhibitor (acrylic copolymer) (% by weight) 1.82 1.75 1.82 1.74 Surface modifier (silicone modified acrylic) (% by weight) 1.2 1.2 1.2 1.2 Flow inhibitor (acrylic derivative) (% by weight) 0.2 0.2 0.2 0.2 solvent Distilled water (% by weight) 47.2 46.4 47.2 47.1 Alcohol-based (weight (%)) 9.18 10.21 9.18 11.18 Glycol system (weight (%)) 13.4 13.14 13.4 13.36 Gross weight (%) 100 100.2 100 100

Experimental Example 1: Measurement of blackness

The blackness (Mf) X of the coating films containing only carbon black and the pigment contents of the coating films of Examples 2 to 7 prepared by changing the content of carbon black to 2 wt% and the glass flakes to 0.01 wt% to 0.21 wt% -RITE MA68II device, and evaluated according to ISO 7724, and the results are shown in FIG. 6 and FIG.

The blackness is represented by the Mf value established by Lippok-Lohmer. The Mf value is calculated from the tristimulus values (Xn, Yn, Zn) of the light source measured by the spectrophotometer and the tristimulus values (X, Y, Z ) Was calculated based on the following equation.

Mf = 100 [log (Xn / X) -log (Zn / Z) + log (Yn / Y)]

Legend: ◎ (190 ~ 200) - Excellent, ○ (180 ~ 189) - Good, △ (179 or less) - Inferiority

As can be seen from FIG. 6, the blackness increases as the content of carbon black increases. Specifically, when 0.8 wt% of carbon black is contained, the degree of blackness was only about 172, but when the amount of carbon black was 1.2 wt% to 2.8 wt%, the degree of blackness was about 190 or more. On the other hand, when the carbon black is 2.4 wt% or more, the degree of increase in blackness is decreased.

As can be seen from FIG. 7, when the glass flake content was changed from 0.01 wt% to 0.21 wt% based on the carbon black content of 2 wt%, it was found that the blackness decreased as the glass flake content increased .

Specifically, when the glass flake content is 0.01 wt% to 0.17 wt%, the blackness gradually decreases, but when the glass flake content is 0.21 wt%, the blackness sharply decreases as compared with 0.17 wt%. Therefore, when the glass flakes are contained in a specific range, that is, 0.05 to 0.17% by weight based on 2% by weight of carbon black, the properties of glass flakes, i.e., Can be expected to improve.

Experimental Example 2: Particle Sense (SG)

The graininess was measured using BYK-GARDNER BYK-mac equipment. BYK-mac measures L *, a *, b * with a commonly used colorimeter and calculates SG (SPARKLE GRADE) using the calculation formula developed by BYK-GARDNER using this measurement data. SG is a value obtained by quantifying the degree of glitter of particles in a coating film. The SG values obtained by measuring the angle of incidence of light on the coating film at 15 degrees, 45 degrees, and 75 degrees were averaged and expressed as a result.

In addition, the particle feel (SG value) was evaluated by visually observing the coating film surface of each coated plate and evaluated according to the following criteria.

Visual Evaluation Criteria:

◎ (4.5 ~ 5)

○ (2 to 3.9): Excellent in particle feel and clear color

△ (1.5 to 1.9): The feeling of the particle is lowered, the color is slightly turbid

 × (0 to 1.4): The particle feeling is dull and the color is cloudy

division Comparative Example Example 1 (double layer) Comparative Example 1 (single layer) Comparative Example 2 (single layer) Pigment Carbon black O O O MICA O Glass flake O Blackness ◎ (190 ~ 200) ? (170-180) (187) Particle sensation (none) ○ (2 ~ 5) ◎ (4.7)

As shown in Table 2, in Comparative Example 1 including a single-layer base coat layer containing only carbon black, blackness was excellent, but no particle feeling was observed. As in Comparative Example 2, Comparative Example 2 including a single-layer base coat layer using MICA mixed with carbon black and a pigment expressing a particulate feel showed good particle feel, but had a blackness lower than 180, which was lower than Comparative Example 1 .

On the other hand, Example 1 containing carbon black as the first base layer and glass flake as the second base layer and including the base coat layer of the double layer exhibited excellent particle feel while maintaining good blackness.

Experimental Example 3: Measurement of other physical properties

(1) glossy

Gloss was measured using BYK GLOSS METER.

(2) Hardness

The hardness of the coating was measured using a Mitsubishi Uni pencil.

(3) Impact resistance

And measured using a DuPont impact tester. 500 g weight and 1/2 curved surface were used.

(4) Adhesiveness

After making 100 lattices on the coated surface using a blade, the peeling test was performed using a tape to confirm that the result was M-2.5 or more.

(5) Sand hiding power

# 600 straight sanding (STRAIGHT SANDING).

(6) Re-construction

The mark of the repainted portion and whether or not it was developed were observed.

(7) Water resistance and moisture resistance

It was confirmed whether or not the appearance was abnormal, and it was confirmed that it was M-2.5 or more in the same manner as the adhesion evaluation method.

(8) Weatherability

And measured using a Xenon arc weatherometer. The CAM 180 had a gloss retention of more than 90% at 1000 hrs.

(9) Layer separation feeling (depth sense)

Each coating film surface was visually observed and evaluated according to the following criteria.

Visual Evaluation Criteria:

○: Large brightness change from highlights to shades

△: The brightness change from the highlight to the shade is slightly smaller and the depth feeling is slightly lowered

×: Small change of brightness from highlight to shade, and no depth feeling

Property measurement Remarks
(Evaluation standard) Evaluation results Comparative Example 2 Example 1 The first base layer The second base layer Base coat layer Container state No foreign matters and evenly dispersed in stirring Good Good Good Viscosity FORD CUP # 4 51 seconds 52 seconds 51 seconds Dilution stability With no significant precipitation, even dispersion Good Good Good Storage stability There should be no significant difference compared to before storage Good Good Good importance - 1.010 1.012 1.011 Nonvolatile matter - 22% 23.4% 19.2% Coat Polish High gloss: 20 'method 88 ↑ 88.7 88.4 Hardness B or more HB HB Impact resistance DuPONT type impactor should be more than 20cm 50cm 50cm Attachment Should be M-2.5 or higher M-1.0 M-1.0 Sand hiding power
(탆) # 600 Straight Standing 7 7 Re-construction 1. Repainted parts mark (MARK)
2.No SANDING attachment M-2.5 or more Good, M-1 Good, M-1 Water resistance M-2.5 or higher, no abnormal appearance M-1 M-1 Moisture resistance M-2.5 or higher, no abnormal appearance M-1 M-1 Weatherability Gloss retention: 90% ↑, Adhesion M-2.5 ↑
Discoloration (ΔE) = 1.0 ↓ (WHITE series), 3.0 ↓ (other colors) 96.4% / M-1
? E = 0.93 96.5% / M-1
? E = 0.81

Example 1 according to an embodiment of the present invention not only improves the particle feel while maintaining excellent blackness, but also has properties equivalent or superior to those of Comparative Example 1, which has excellent physical properties as a conventional product, as shown in Table 3 Can be achieved.

10: middle floor
20: first base layer
25: second base layer
30: Clear coat layer

Claims (15)

A base coat layer, and a clearcoat layer sequentially formed on a substrate,
Wherein the base coat layer comprises a first base layer comprising a black pigment and a second base layer comprising a glass flake on the first base layer,
The second base layer comprises 0.05 to 0.17% by weight of a glass paste, 10 to 50% by weight of a polymer resin, 0.5 to 5% by weight of an acrylic additive and 40% by weight of a solvent based on the total weight of the second base coating composition, To 85% by weight of the second base coating composition. The method according to claim 1,
Wherein the glass flake has an average particle size of 2 to 50 占 퐉. The method according to claim 1,
Wherein the second base layer does not comprise carbon black. The method according to claim 1,
Wherein the black pigment comprises carbon black. The method according to claim 1,
Wherein the first base layer comprises from 0.5% to 10% by weight of a black pigment, from 10% to 50% by weight of a polymeric resin, from 0.5% to 5% by weight of an acrylic additive and from 40% &Lt; / RTI &gt; 85% by weight of the first base coating composition. delete The method according to claim 1,
Wherein the content ratio of the black pigment to the glass flake is 1: 0.02 to 0.9 weight ratio. The method according to claim 1,
Wherein the thickness of the first base layer is 7 to 12 占 퐉. The method according to claim 1,
Wherein the thickness of the second base layer is 2 to 5 占 퐉. The method of claim 5,
Wherein the polymer resin is any one selected from the group consisting of an acrylic resin, a polyester resin, and melamine formaldehyde, or a mixture of two or more thereof. The method of claim 5,
Wherein the acrylic additive is any one selected from the group consisting of an acrylic copolymer, a silicone-modified acrylic compound and an acrylic derivative, or a mixture of two or more thereof. The method of claim 5,
Wherein the solvent is any one selected from the group consisting of water, an alcohol-based solvent, and a glycol-based solvent, or a mixture of two or more thereof. Coating a first base coating composition comprising a black pigment on the intermediate layer formed by coating the intermediate coating composition to form a first base layer;
Coating a second base coating composition comprising a glass flake on the first base layer to form a second base layer; And
Coating a clear coat coating composition on the second base layer to form a clear coat layer,
The second base coating composition comprises 0.05 to 0.17% by weight of a glass paste, 10 to 50% by weight of a polymer resin, 0.5 to 5% by weight of an acrylic additive and 40 to 40% by weight of a solvent, based on the total weight of the second base coating composition % To 85% by weight of the composition. 14. The method of claim 13,
Wherein the thickness of the first base layer is 7 to 12 占 퐉. 14. The method of claim 13,
Wherein the thickness of the second base layer is 2 to 5 占 퐉.

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