JPH105681A - Application method for varicolored pattern coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a varicolored pattern coating film excellent in finish properties, substrate concealability, water resistance, weatherability and durability by applying the same coating material twice or more. SOLUTION: A varicolored pattern coating material containing one or more kind of enamel particles formed by dispersing enamel prepared by mixing and dispersing a compsn. based on a resin (A), pigment (B) and an org. solvent (C) in an aq. dispersion medium is applied to an article to be coated twice or more. In this case, at a time of first coating, a spray gun with a nozzle caliber of 1-4mm is used as a coating machine and, when the air supply system of the coating machine is a compressor type, coating air pressure is set to 0.2-0.5MPa. When the air supply system of the coating machine is a high speed turbine type, coating air quantity is set to 800-7,500l/min.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for applying an oil-in-water type multi-color paint, and more particularly, to a finish, a base concealing property, a water resistance, a weather resistance, and the like by two or more coatings using the same paint. The present invention relates to a method for applying a colorful paint capable of forming a colorful paint film having excellent durability. INDUSTRIAL APPLICABILITY The present invention is applicable to painting inside and outside buildings, dry building materials, roofs, vehicles, bridges, ships, furniture, woodwork, and the like.

[0002]

2. Description of the Related Art Oil-in-water type colorful paints specified in JIS K 5667 are obtained by dispersing an enamel mainly composed of a resin, a pigment and an organic solvent in water. The dispersed particles are present discontinuously.

[0003] Conventionally, the paint finishing using such oil-in-water type colorful pattern paint has focused on a variety of particulate design characteristics due to the discontinuity, and forms a discontinuous film so that the particles are not fused. Therefore, in order to conceal the base and adjust the base, it is necessary to apply a base paint or a paint for concealment called a binder coat before applying the multicolor paint. Was. These paints use a matte paint with a high pigment concentration to make the suction unevenness in the base material and the unevenness of the base material less noticeable, and are sufficient for building interiors, etc. In order to paint under severe environment such as surroundings, the ability to follow the substrate was poor and the weather resistance and water resistance were insufficient.

[0004] Therefore, in such a harsh environment, the coating finish using the multicolor pattern paint causes a discontinuous pattern particle film from the concealing coating surface due to cracks and the like generated in the underlying concealing coating film. There was a problem such as peeling off and it was not applied.

[0005] On the other hand, there has been proposed a paint finish using an elastic paint having a followability to a base material as an undercoat (for example, Japanese Patent Application Laid-Open No. 62-87285). According to this method, the problem due to the ground surface is eliminated,
In a severe environment such as an architectural exterior or a water environment, the pattern coating itself, which is a discontinuous film, deteriorates and peels off due to cracks between the pattern particles, making it very difficult to maintain the initial design.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, a multi-color paint has been applied twice under specific coating conditions using a spray gun having a specific nozzle diameter. By overcoating, it is possible to form a continuous pattern coating film, and it is possible to form a variety of pattern coating films having excellent water resistance and durability, excellent underground concealing properties, and without using a concealing paint. The invention has been completed.

That is, according to the present invention, an enamel is prepared by mixing and dispersing a composition mainly composed of a resin (A), a pigment (B) and an organic solvent (C) on an object to be coated, and dispersing the composition in an aqueous dispersion medium. A multi-color paint containing at least one kind of enamel dispersed particles comprising a spray gun having a nozzle diameter of 1 to 4 mm as a coating machine during the first coating. The air supply system of the machine is a compressor
A multi-color pattern characterized by a coating air pressure of 0.2 to 0.5 MPa for a mold, or a coating air amount of 800 to 7,500 liters / minute for a high-speed turbine type air supply system of a coating machine. It is intended to provide a method of applying paint.

Hereinafter, the present invention will be described.

The spray gun used in the present invention is of a type capable of atomizing paint by air pressure.
The nozzle diameter of the spray gun used at the time of the first coating is 1 to 4 mm, preferably 1.5 to 3 mm. The spray gun used in the second and subsequent coatings preferably has a nozzle diameter of 2 to 4 mm, preferably 2.5 to 3 mm.

As a method of supplying paint to the spray gun, any of conventionally known types such as a gravity type, a suction type, and a pressure feed type can be applied. However, the proportion of the paint discharge amount to the amount of air used is zero. It is desirable to select one that is at least 1%. If this ratio is less than 0.1%, atomization at the time of atomization is good, but the pattern particles in the coating film tend to be fine, which is not desirable.

According to the method of the present invention, the multi-color paint is applied twice or more. At the time of the first coating, if the air supply system of the coating machine is a compressor type, the coating air pressure of the spray gun is set to 0.2 to 0. 0.5 MPa, preferably 0.25 to
0.5 MPa, or when the air supply system of the coating machine is a high-speed turbine type, the coating air amount of the spray gun is 800 to
7,500 l / min, preferably 3,000 to 6,
000 liter / min. Here, a coating machine with an air supply system of a compressor type is a coating machine of a type for supplying compressed air, and a coating machine with an air supply system of a high-speed turbine type is H.264. V. L. P. (High Volume Low Pr
essure) type coating machine.

The first coating (hereinafter referred to as "base spray coating")
The object of the present invention is to provide a coating film made of the multicolored paint as a continuous film and to adhere to an object to be coated, thereby imparting a substrate hiding property. That is, by applying a relatively high share as the spray gun coating air pressure (or the coating air amount), the coating particles are partially broken, and the fusion of the particles becomes strong, and the coating particles adhere to the object to be coated. This makes it possible to form a continuous film.

If the spray gun coating air pressure during the first coating is less than 0.2 MPa or the spray gun coating air flow rate is less than 800 liters / minute, the coating particles are not broken and the particles do not fuse together. Adhesiveness to the object to be coated and underlying layer concealing property cannot be obtained, while 0.5 MPa or 7,500
If it exceeds 1 liter / min, it is necessary to increase the pressure resistance of the coating machine, and a large improvement effect on the fusing property of the coating particles and the adhesion to the coating object cannot be obtained.

In the first coating, the distance between the object to be coated and the gun is 10 to 40 cm, preferably 10 to 30 cm, and the coating amount is 0.1 to 0.7 kg / m ² , preferably 0.2 to 0.7 kg / m ² .
Desirably, it is 0.5 kg / m ² . If the distance between the object to be coated and the gun is greater than 40 cm, the density of the paint at the time of coating becomes small, and the paint particles are not sufficiently fused to each other, which is not desirable. If the coating amount is less than 0.1 kg / m ² , it is difficult to completely cover the base as a continuous film.
If it exceeds 7 kg / m ² , the coating film tends to sag, which is not desirable.

As described above, it is preferable to perform the second coating after the continuous film formed on the object to be coated by the first coating reaches the touch dryness. It is not desirable to apply the second and subsequent coatings before touch drying, because after the second and subsequent dryings, the skin tends to have a purulent state and the coating film easily drips.

In the method of the present invention, the second and subsequent coatings (hereinafter referred to as
The "pattern spray coating" is intended to be a non-continuous film in which a spherical pattern is formed by a multi-color paint. In the second and subsequent coatings, the air supply system of the coating machine is set to a coating air pressure of 0.05 to less in a compressor type.
0.3 MPa, preferably 0.08 to 0.2 MPa, or when the air supply system of the coating machine is a high-speed turbine type, the coating air amount is 300 to 3,000 liter / min, preferably 500 to 2,800. It is desirable to use liter / minute. Further, the distance between the object and the gun is 20 to 100 cm, preferably 20 to 80 cm, and the coating amount is 0.1 to 0.7 k.
g / m ² , preferably 0.2 to 0.5 kg / m ² . The spray gun coating air pressure at the time of the second and subsequent coatings is 0.3 MPa, or the coating air amount is 3.0
If it exceeds 00 liters / minute, the pattern paint particles are distorted and the finish is undesirably reduced. When the distance between the object to be coated and the gun is less than 20 cm, the pattern particles become thin or deformed. On the other hand, when the distance is more than 100 cm, the pattern particles become sparse and difficult to form a good pattern, which is not desirable.

The substrate to which the method of the present invention is applied includes:
For example, concrete surface, mortar surface, slate plate, part
Light plate, stone, wood, paper, plastic, metal and other material surfaces, and those coated with a primer for adjusting the ground surface and improving adhesion, and further applied with an elastic material capable of forming irregularities There are also things. As the primer, conventionally known water-based or organic solvent-based paints containing a resin as a main component such as acrylic, styrene-acryl, vinyl chloride, vinyl chloride-vinyl acetate, and ethylene-vinyl acetate can be used. . As elastic material,
Conventionally known synthetic resin emulsion-based, cement-based, polymer-cement-based, etc., multi-layer finishing base materials and base adjustment coating materials can be used.

The multicolor paint used in the present invention is obtained by mixing and dispersing a composition mainly composed of a resin (A), a pigment (B) and an organic solvent (C) to obtain an enamel, which is dispersed in an aqueous dispersion medium. Containing at least one kind of enamel dispersion particles.

As the resin (A), nitrocellulo-
Conventionally known resins such as polystyrene, polyvinyltoluene, and polybutadiene can be used. Particularly, when the resin is applied to outdoor use in terms of weather resistance and water resistance, a monomer containing at least 20% by weight of an acrylic monomer is used. A weight average molecular weight of 20,000 to 20 obtained by copolymerizing the mixture;
A copolymer having an acid value of 2 or less at 000 can be suitably used.

Examples of the acrylic monomer include, for example, methyl (meth) acrylate and ethyl (meth) acrylate.
Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate
And alkyl or cycloalkyl esters of acrylic acid or methacrylic acid having 1 to 24 carbon atoms, such as isobutyl, isobornyl (meth) acrylate, etc., and these are used alone or in combination of two or more. Acrylic monomers having a hydrophilic functional group such as a carboxyl group, a hydroxyl group, an amide group, and an amine group may be used in combination with the above monomers in a small amount as long as the stability of the enamel-dispersed particles is not impaired. .

Further, other monomers include, for example, vinyl aromatic compounds such as styrene, α-methylstyrene and vinyltoluene; and alkoxysilyl groups such as vinyltrimethoxysilane and γ- (meth) acryloyloxypropyltrimethoxysilane. Monomers: Perfluoroalkyl (meth) acrylates such as perfluorobutylethyl (meth) acrylate and perfluorooctylethyl (meth) acrylate; vinyl chloride, fluoroolefins, and the like are copolymerizable with the above acrylic monomers. No. These can be appropriately selected and used according to desired physical properties.

The above monomer mixture can be obtained by copolymerization in the presence of a radical polymerization initiator by a conventional method such as a solution polymerization method. As the radical polymerization initiator,
Peroxides such as benzoyl peroxide, t-butylperoxy-2-ethylhexanoate, cumyl peroxide;
Azo compounds such as α, α′-azobisisobutyronitrile and azobisdimethylvaleronitrile are exemplified.

Examples of the solvent used at the time of polymerization include aliphatic hydrocarbons such as petroleum benzene, mineral spirit and tapene; aromatic hydrocarbons such as benzene, toluene and xylene; and alicyclic hydrocarbons such as cyclohexane. System, other dichloroethane, trichlene, texano-
Toluene, texanol isobutylate, 2-ethylhexyl alcohol, diisobutyl ketone, 2-ethylhexyl acetate, dibutyl phthalate, dioctyl phthalate
A solvent having a low affinity for water, such as water, can be used alone or as a mixture. Preferably, an aliphatic hydrocarbon-based solvent is suitable from the viewpoint of the odor at the time of coating and the working environment.

When a poor solvent such as an aliphatic hydrocarbon-based solvent is used as a solvent for the polymerization, the SP of the monomer mixture used above may be used for good enamelling.
It is desirable to appropriately adjust the (solubility parameter) value (as a measure of hydrophilicity), and particularly a monomer having high hydrophilicity.
, The SP value (solubility parameter value) depending on the acrylic monomer used is 7.6-8.
6, preferably 7.8 to 8.4,
It is appropriate to select the acrylic monomers to be used so as to fall within this range.

The above-mentioned copolymer is the above-mentioned acrylic monomer.
Is preferably obtained by copolymerizing a monomer mixture containing at least 20% by weight or more, preferably 50% by weight or more, particularly from 0 to 50% by weight, and preferably from 10 to 30% by weight, in view of weather resistance and water resistance. %, Acrylic monomer
20-100% by weight, preferably 50-90% by weight, and other monomers -0-80% by weight, preferably 0-4%
Those obtained by copolymerizing a monomer mixture containing 0% by weight are preferred.

The above copolymer has a weight average molecular weight of 20,0.
00 to 200,000, preferably 50,000 to 15
It is 0000. If the molecular weight is less than 20,000, the weather resistance of the coating film and the stability of the enamel-dispersed particles in the coating material will decrease, while if it exceeds 200,000, the coating workability and the film-forming property will be poor.

The above-mentioned copolymer is a copolymer having an acid value of 2 or less, preferably less than 1. If the acid value exceeds 2, the stability of the enamel-dispersed particles is unpreferably reduced. In addition, the copolymer has a glass transition temperature (Tg) of 0 to 0.
When the Tg is less than 0 ° C., the stability of the enamel-dispersed particles, the water resistance of the coating film are reduced, and the film is easily stained.
When the temperature exceeds ℃, the film forming property is lowered and the coating film becomes brittle, which is not preferable.

As the pigment (B), conventionally known coloring pigments and extenders can be used. Examples of the coloring pigments include titanium oxide, carbon black, red iron oxide, iron oxide, phthalocyanine blue, and phthalocyanine resin. ,
Benzimidazolone, azo pigment, quinacridone red,
Examples include graphite, chromium oxide, ultramarine, pearl pigment, metal powder, and the like.
Talc, barium sulfate, white carbon, alumina,
Bentonite, silica, mica and the like can be mentioned, and they can be used alone or in combination. The content of these pigments in the enamel can be appropriately selected depending on the intended design and the like, but is desirably 70% by weight or less, preferably 50% by weight or less. If the content is more than 70% by weight, the mechanical strength of the enamel is reduced, and the stability of the enamel-dispersed particles and the sprayability during coating are reduced. It is not desirable because viscosity adjustment and the like are likely to be inconvenient.

As the organic solvent (C), conventionally known organic solvents can be used, for example, aliphatic hydrocarbons such as petroleum benzene, mineral spirit and tapene, and aromatic hydrocarbons such as benzene, toluene and xylene. , Alicyclic hydrocarbons such as cyclohexane, other dichloroethane,
Tricklen, Texanol, Texanol isobutylene
2-ethylhexyl alcohol, diisobutyl ketone, 2-ethylhexyl acetate, dibutyl phthalate
G, dioctyl phthalate, methanol, ethanol,
Butanol, acetone, methyl ethyl ketone, methyl isobutyl ketone and the like can be used, and these can be used alone or as a mixture, and aliphatic hydrocarbon solvents are preferable from the viewpoint of odor at the time of coating and working environment. The content of the organic solvent (C) in the enamel is preferably 20 to 70% by weight. If it is less than 20% by weight, adjustment of the specific gravity and viscosity of the enamel tends to be inconvenient, while if it exceeds 70% by weight, the mechanical strength of the enamel is reduced, and the stability of the enamel-dispersed particles and the sprayability during coating are reduced. It is not desirable because it may cause

The above resin (A), pigment (B), organic solvent (C) and the like are mixed and dispersed according to a conventional method such as using a disperser such as a disperser, a sand mill, a roll mill or a ball mill. To enamel. Further, additives such as a dispersant, an antifoaming agent, and a plasticizer may be appropriately added to the composition as needed.

The specific gravity of the enamel obtained as described above is 0.90 to 0.95 in view of the stability of the enamel-dispersed particles in the paint.
A range of 2.5, preferably 0.95 to 1.5 is suitable. Outside of this range, the dispersed particles float or settle during storage of the coating and are liable to fuse, which is not preferred. The viscosity of the enamel is appropriately determined depending on the intended design, but is preferably 1 Pa · s or more in view of the mechanical strength of the enamel.

The multi-color paint used in the present invention contains one or more kinds of enamel dispersion particles obtained by dispersing the above-mentioned enamel in an aqueous dispersion medium. It can be obtained as a mixture.

As the aqueous dispersion medium, conventionally known ones can be used, for example, those in which a stabilizer for appropriately stabilizing dispersed particles so that they do not aggregate with each other can be used. As such a stabilizer, any of an organic or inorganic stabilizer can be used. Particularly, a stabilizer which is water-soluble and has a moderately hydrophobic portion is suitable. Examples of such a stabilizer include known protective colloids, such as methyl cellulose, ethyl cellulose, polyvinyl alcohol, casein, tragacanth rubber, carbarium rubber, and cellulose acetate.
Tophthalate, bentonite, hydroxyethyl cellulose, polymethacrylic acid, gum arabic, gum karaya,
Gelatin, sodium alginate, albumin, pectin, xanthan gum, starch, water-soluble urea formaldehyde and the like can be used. Also relatively insoluble salts in water,
For example, clay, talc, barium sulfate, calcium carbonate,
Magnesium carbonate, diatomaceous earth and the like may also be used as the above stabilizer. However, since a large amount is required for stabilization as compared with a water-soluble stabilizer, it is desirable to use as fine a powder as possible.

The aqueous dispersion medium may further contain an electrolyte (sodium chloride, sodium sulfate, magnesium sulfate, etc.), a wetting agent, a film-forming aid, an antifreezing agent, an antifoaming agent, if necessary.
A dye or the like may be appropriately added to such an extent that the stability of the dispersed particles is not impaired.

The aqueous dispersion medium is preferably adjusted to about 45 to 90 (KU value) from the viewpoint of coating workability and stability of dispersed particles.

In the method of dispersing the enamel in the aqueous dispersion medium, the mixing ratio of the enamel to the aqueous dispersion medium is from 1.5 to 1.5.
Conventionally known methods using a normal mixing and dispersing apparatus can be adopted by mixing to about 0.3, but preferably a propeller-type stirrer having, for example, two or three blades capable of mixing the whole with a small shearing force It is desirable to use a device having

When the enamel is dispersed in the aqueous dispersion medium, the enamels for each color required for the intended design are separately dispersed, and the obtained aqueous dispersions are mixed to form a paint.
Alternatively, the enamels of the respective colors can be simultaneously mixed in an aqueous dispersion medium and dispersed to form a coating material, and the former method is generally used from the viewpoint of reproducibility of the pattern color.

The average particle size of the enamel dispersed particles obtained as described above is suitably about 0.1 mm or more from the viewpoint of patternability. The particle size can be selected according to the intended design by appropriately adjusting the enamel composition and viscosity, the type and amount of the stabilizer in the aqueous dispersion medium, and the like. Further, the enamel-dispersed particles are not necessarily spherical, and may be elliptical, teardrop-shaped, or the like.

[0039]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. “Parts” and “%” are “parts by weight” respectively.
And "% by weight".

Preparation of Resin (A) A thermometer, a thermostat, a stirrer, a reflux condenser and a dropping pump were provided in a reactor, 45 parts by weight of mineral spirit were charged, the temperature was raised to 100 ° C. while stirring, and 20 parts of styrene were added. 63 parts of i-butyl methacrylate, i-butyl methacrylate
17 parts of butyl acrylate and t-butyl peroxy-
Mixture of 0.4 part of 2-ethylhexanoate 100.4
Using a dropping pump, the solution was dropped at a constant rate over a period of 3 hours into a reactor in which parts by weight were kept at 100 ° C. After completion of the dropwise addition, the mixture was kept at 100 ° C. for 2 hours and stirring was continued. Thereafter, an additional polymerization initiator (t-butylperoxy-2-ethylhexanoe-
G) A solution prepared by dissolving 0.5 parts by weight of mineral spirits in 30 parts by weight was added dropwise at a constant rate over 1 hour, the reaction was terminated at 100 ° C. for 1 hour, and diluted with 48.8 parts by weight of mineral spirits. did. The obtained copolymer solution was a uniform and transparent solution having a nonvolatile content of 45% by weight. The weight average molecular weight of this copolymer was 98,000,
g was 45 ° C. and the acid value was 0.1.

Production of multicolor paints The copolymer solution, pigment, anti-algal agent and solvent obtained in the above production example were charged into a stainless steel container having a capacity of 2 liters according to the composition shown in Table 1 and stirred for 15 minutes by a disper. Thereafter, the mixture was dispersed for 15 minutes with a desktop sand mill using a glass bead to prepare (white), (red), and (blue) enamels.

[0042]

[Table 1]

Then, 100 parts of tap water, 0.5 parts of methylcellulose, 0.1 part of "SluoF 72N" (preservative, manufactured by Takeda Pharmaceutical Co., Ltd.) and 0.1 part of "BYK-025" (manufactured by BYK Corporation, antifoaming agent) ) 100 parts of the above obtained enamel was mixed with 0.1 part of an aqueous dispersion medium, and the mixture was stirred at a low speed for 15 minutes with a propeller-type stirrer.
Each enamel aqueous dispersion was obtained by dispersing so as to have a range of about 2 mm.

The (white) enamel water dispersion 100 obtained above
Parts, 10 parts of (red) aqueous enamel dispersion and (blue)
10 parts of an aqueous enamel dispersion were mixed and mixed to obtain a multicolored pattern paint A.

Also, "Zolacoat No. 229" (manufactured by Kansai Paint Co., Ltd., nitrocellulose-based colorful paint) and "Zolaton No. 17911SU" (Kansai Paint Co., Ltd., vinyl toluene resin-based colorful paint) ) Were designated as colorful paints B and C, respectively. Examples and Comparative Examples Each of the colorful pattern paints obtained in the above Production Examples was applied to a test plate for the following performance test using a spray gun (*) shown in Table 2 under the coating conditions shown in the same table. The obtained coated plate was subjected to each performance test. Table 2 shows the results.

(*) The spray gun types in Table 2 are as follows. The air supply system is all compressors except l.
Type.

A: “W-87-25W5G”, gravity spray gun manufactured by Iwata Coating Machine Co., Ltd. b: “W-90-25W5P”, 〃, pumping type 〃 c: “W-90-30Y5S”, 〃 , Suction type ｄ d: “W-873”, 、, pressure feed type ｅ e: “W-871-1”, 、, pressurization type ｆ f: “W-871-2”, 、, pressure feed type ｇ g: “F-200B-P20”, manufactured by Meiji Kikai Seisakusho, pumping type ｈ h: “F-200B-P25”, 、, pumping type ｉ i: “F-200B-P30”, 〃, pumping type 〃 j: “Rissingan” MG-1D ", Iwata Co., Ltd., gravity type ｋ k:" Listagun MG-6B ", 、, gravity type 〃 l:" No152 * 1 ", VOLUMAIR, HVLP pressurized type 〃 m:" W " -87-20R5S ", manufactured by Iwata Coating Machine Co., Ltd., gravity type n:" W-90-18N5P ",圧, pressure feeding type 〃 o: “F-200B-P15”, manufactured by Meiji Kikai Seisakusho, pressure feeding type 〃 (1) Patterning Ales holder-G (manufactured by Kansai Paint Co., Ltd.) on a 70 × 150 × 4 mm slate plate , Aqueous base conditioner) was applied with a roller so as to have an application amount of 800 to 1,000 g / m ^2, and dried at room temperature for 24 hours to obtain a test plate. After leaving the obtained coated plate at room temperature for 24 hours, the pattern of the coated plate was visually evaluated.

◎: The pattern of the particles is clear. 部分: A small portion of the pattern of the particles is slightly observed. Δ: The pattern is distorted and a considerable amount of linear pattern is observed. X: The pattern is completely distorted. No pattern of particles is seen at all. (2) Concealment A test plate was prepared by applying "Ales Aqua Letan Black" (Kansai Paint Co., Ltd., water-based topcoat) on the test plate of (1) above with a brush. Then, the concealing property of the coated plate obtained by applying each of the various pattern paints to the resultant was visually evaluated.

：: Black band is not visible at all, and concealment is good. ご: Very slightly black band is visible, but there is no practical problem. Δ: Black band is partially visible, and there is a practical problem. (3) Repeated heating / cooling test The coated plate prepared in the same manner as in (1) above was further cooled to room temperature for 10 minutes.
After drying for days, the coated plate was immersed in water for 18 hours according to JIS A 6909 hot / cold repetition test.
3 hours cooling in a 20 ° C. incubator to 5 hours in a 50 ° C. incubator
Time heating> was defined as one cycle, and the state of the coating film surface after the 10 cycle test was visually evaluated.

：: No cracking or discoloration was observed on the coating film surface, and no discoloration was observed. ：: Any cracking, discoloration, or discoloration was recognized on the coating film surface. Δ: Cracking, discoloration, or discoloration was observed on the coating film surface. Either one is observed. ×: Cracking, peeling and discoloration are remarkably observed on the coating film surface.

[0051]

According to the present invention, the first and second and subsequent multi-color paints are applied under the respective coating conditions using a spray gun having a specific nozzle diameter.
It is possible to form a continuous pattern coating film, and it is possible to easily form a variety of pattern coating films having excellent base water concealing property, excellent water resistance and durability without using a concealing paint.

[0052]

[Table 2]

Claims (5)

[Claims] 1. An enamel obtained by mixing and dispersing a composition containing a resin (A), a pigment (B) and an organic solvent (C) as main components on an object to be coated to form an enamel and dispersing the composition in an aqueous dispersion medium. A coating method in which a multi-color paint containing at least one kind of dispersed particles is applied twice or more times. In the first coating, a spray gun having a nozzle diameter of 1 to 4 mm is used as a coating machine, and the air of the coating machine is used. When the supply system is a compressor type, the coating air pressure is 0.2 to 0.5 MPa, or when the coating machine air supply system is a high-speed turbine type, the coating air amount is 800 to 0.5 MPa.
A method for applying a multi-colored paint, wherein the coating rate is 7,500 liters / minute. 2. In the first coating, the distance between the object to be coated and the gun is 10 to 40 cm, and the coating amount is 0.1 to 0.7 kg / m.
^2. The coating method according to claim 1, wherein the coating method is 2. 3. In the second and subsequent coatings, a spray gun having a nozzle diameter of 2 to 4 mm is used as a coating machine and the coating air pressure is 0.05 to 0.3 MPa when the air supply system of the coating machine is a compressor type. Or, if the air supply system of the coating machine is a high-speed turbine type, the amount of coating air is 300 to 3,
The coating method according to claim 1 or 2, wherein the coating rate is 000 liter / min. 4. In the second and subsequent coatings, the distance between the object to be coated and the gun is set to 20 to 100 cm, and the coating amount is set to 0.1 to 0.7 k.
The coating method of any one of claims 1 to 3, g / m ^2. 5. A resin (A) obtained by copolymerizing a monomer mixture containing at least 20% by weight of an acrylic monomer, and having a weight average molecular weight of 20,000 to 200,0.
The coating method according to any one of claims 1 to 4, wherein the copolymer is a copolymer having an acid value of 2 or less.