JPH1133485A - Two-tone finish coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-tone finish coating method capable of forming coating films having excellent finish appearance, chipping resistance, etc., on the outside plate parts of an automotive body. SOLUTION: In the method for coating the outside plate part of the automotive body by using two kinds of colored coating materials varying in color tones and finishing the coating films to two tones, the entire surface of the outside plate part is coated with an electrodeposition coating material and is cured by heating and thereafter, the parts likely to be struck with gravel and pebbles is coated with the vinyl chloride resin-based chipping resistant coating material and the polyurethane resin-based chipping resistant coating material. After the entire surface of the outside plate part is coated with an intermediate coating material, the lower part of the outside plate parts is coated with the first colored coating material and the four-layered coating films are simultaneously cured by heating and thereafter, only the upper part of the outside plate part is coated with the second colored coating material and clear coating material. These two-layered coating films of the upper part are then simultaneously cured by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel coating method for two-tone finishing of an outer panel of an automobile body.

[0002]

2. Description of the Related Art There are already known coating methods in which an upper part and a lower part of an outer panel portion of an automobile body are separately applied using two kinds of coloring paints having different color tones to achieve a two-tone finish. For example, in the outer plate of an automobile body that is coated with an electrodeposition paint and then cured by heating, the lower portion thereof is easily hit by gravel or pebbles that are mainly jumped up during traveling, thereby partially peeling off the coating film. In order to prevent this, apply a vinyl chloride resin-based chipping-resistant paint in advance to that part, apply an intermediate coating paint on the entire surface of the outer plate, and further apply a After applying one colored paint, it is heated to simultaneously cure the three-layer paint film composed of the vinyl chloride resin paint, the intermediate paint and the first colored paint, and then the lower part is masked and then the upper part is coated. After the second colored paint and the clear paint are applied, heating is performed to simultaneously cure the two-layer coating film composed of the second colored paint and the clear paint, thereby completing the two-tone paint.

However, in the lower part of the vehicle body, a vinyl chloride resin-based coating, an intermediate coating and a first colored coating are each applied in an uncured state, and then heated to simultaneously cure these three-layer coatings. If it does, the gloss of the colored paint film is reduced, and the orientation of the metallic pigment contained in the paint film is disturbed, and the finished appearance is poor. Has insufficient defects, such as insufficient finished smoothness.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a two-tone finish coating method capable of forming a coating film having excellent finish appearance and chipping resistance on an outer panel of an automobile body.

[0005]

SUMMARY OF THE INVENTION The inventor of the present invention has made intensive studies to solve the various deficiencies in the above-mentioned conventional coating method in the case where the upper and lower portions of the outer body portion of an automobile body are separately painted to achieve two tones. As a result, in the coating method, in particular, by coating a vinyl chloride resin-based chipping-resistant paint on the lower part and then further applying a polyurethane resin-based chipping-resistant paint on the coated surface, the first colored paint coating is applied. It can effectively prevent the decrease in the gloss of the film, the disorder of its orientation when a metallic pigment is contained, and the decrease in the smoothness due to the vinyl chloride resin paint. It has been found that a coating film having excellent properties and the like can be formed and the above object can be achieved, and based on this, the present invention has been completed.

That is, the present invention relates to a method for coating an outer panel of an automobile body in which a two-tone finish is obtained by using two kinds of colored coatings having different color tones. After heat hardening, gravel and pebbles are easy to hit,
A vinyl chloride resin-based chipping-resistant paint and a polyurethane resin-based chipping-resistant paint are applied, then an intermediate coating is applied over the entire outer panel, and then a first colored coating is applied to a lower portion of the outer panel. After heating and simultaneously curing these four-layer coatings, a second colored paint and a clear paint are applied only to the upper part of the outer panel, and heated to simultaneously apply these two-layer coatings on the upper part. The present invention relates to a two-tone finish coating method characterized by curing.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The coating method of the present invention will be described below more specifically.

The object to be coated in the coating method of the present invention is an automobile body, and a metal automobile body is particularly suitable. The vehicle body outer panel portion in the present invention is a portion located outside the vehicle body, for example, a locker, a door, a fender,
Aprons, hoods, roofs, trunk lids, and the like. In addition, the part of the car body that is easily hit by gravel, pebbles, etc.
The lower part of a door, the lower part of a fender, an apron, etc. are mentioned. Further, the lower portion of the vehicle body outer panel portion is determined in consideration of a design property of a desired two-tone finish, and examples thereof include a locker, a lower portion of a door, a lower portion of a fender, and an apron. Further, the upper portion of the vehicle body outer plate portion is a portion above the lower portion, and includes, for example, an upper portion of a door, an upper portion of a fender, a hood, and the like.

The electrodeposition paint applied to the object to be coated is for improving rust prevention, adhesion and the like, and a cationic electrodeposition paint is preferred.

[0010] As the cationic electrodeposition paint, those known per se can be used, and examples thereof include cationic polymer compounds in which an amino group is introduced into an acrylic resin or an epoxy resin having a crosslinkable functional group. It is preferable to use water or water dispersed by neutralization with an organic acid or an inorganic acid or the like, and further blend a blocked polyisocyanate or the like as a crosslinking agent.

An automobile body (object to be coated) is immersed in a bath of these cationic electrodeposition paints as a cathode to perform electrodeposition coating, and the film thickness is usually in the range of 10 to 50 μm based on the cured coating film. Preferably, the coating film can be crosslinked and cured by heating at 140 to 220 ° C for 10 to 40 minutes.

In the coating method of the present invention, the coating portion of the vinyl chloride resin-based chipping-resistant paint and the polyurethane resin-based chipping-resistant paint is an outer plate portion of an automobile body obtained by electrodeposition coating and heating and curing. It is the part of the car body that is easily hit by gravel, pebbles, etc., which have been flipped up inside. Also,
It is not necessary to match the parts to be coated with these chipping-resistant paints and the parts to be coated with the first colored paint described below,
As described above, the chipping-resistant paint is applied to a portion where pebbles or the like are likely to hit, while the application site of the first colored paint is determined in consideration of the design property of the intended two-tone finish.

The vinyl chloride resin paint is a paint which is mainly applied to prevent the paint film from being partially peeled off by pebbles or the like which are flipped up during traveling and has excellent chipping resistance. It is preferable to form a film, specifically, containing a vinyl chloride resin, a filler and a plasticizer,
Further, there may be mentioned a thermoplastic liquid paint containing an organic solvent, a stabilizer and the like as required.

The vinyl chloride resin contains vinyl chloride as a main component, and further contains vinyl acetate, maleic acid, (meth) acrylic acid, acrylic esters, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, styrene, acrylonitrile, etc., if necessary. (Co) polymerized resin.

Examples of the filler include coloring pigments such as titanium white, barium sulfate, barium carbonate, calcium carbonate, clay, silica, white carbon, talc, magnesium carbonate, carbon black, mica, zinc white, and cadmium red; And the like.

Examples of the plasticizer include dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, tricresyl phosphate, triphenyl phosphate, dibutyl sebacate and the like.

Examples of the organic solvent include hydrocarbon solvents, ester solvents, ether solvents, alcohol solvents, ketone solvents and the like.

The composition ratio of these components in the vinyl chloride resin paint can be arbitrarily selected according to the purpose.
5 to 15 fillers per 100 parts by weight of vinyl chloride resin
0 parts by weight and the plasticizer are preferably 5 to 100 parts by weight.

The vinyl chloride resin-based paint is applied to the electrodeposited surface of the outer plate portion of the automobile, which is electrodeposited and heat-cured, where the gravel, pebbles, etc. are likely to hit, and the cured coating film is applied in an amount of about 200 to
It is preferable to apply a coating having a thickness of 400 μm by a coating method such as airless spraying or air spraying.

In the coating method of the present invention, a polyurethane resin-based paint is applied to the coating surface of an uncured vinyl chloride-based paint.

The polyurethane resin paint is a liquid thermosetting paint containing a urethane-modified polyester resin, a block polyisocyanate compound, a melamine resin, an epoxy resin and a filler.

The urethane-modified polyester resin is a resin obtained by subjecting a polyester polyol and a polyisocyanate compound to a urethanization reaction in an excess molar ratio of hydroxyl groups, and has two or more hydroxyl groups in one molecule.

The blocked polyisocyanate compound is a compound obtained by blocking all or most of the free isocyanate groups of the polyisocyanate compound with a blocking agent. When heated to a temperature higher than the dissociation temperature, the free isocyanate groups are regenerated to form a crosslinking agent. Function as

The polyisocyanate compound is a compound having two or more isocyanate groups in one molecule, and includes aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, violet type adduct, isocyanuric ring type adduct and the like. can give. Examples of the blocking agent include phenols, oximes, lactams, active methylene compounds, alcohols, acid amide compounds, imide compounds, amine compounds, imidazole compounds, urea compounds, carbamic acid compounds, Imine compounds, mercaptans and the like can be used.

The urethane-forming reaction between the polyesterol and the polyisocyanate compound can be carried out by a usual method. The urethane-modified polyester resin thus obtained has a number average molecular weight of 1,500 to 350,000 and a hydroxyl value of 50 to 200 mg KOH. / G is suitable.

As the melamine resin, a methylolated melamine and an etherified melamine resin obtained by reacting the methylolated melamine with a monohydric alcohol having 1 to 6 carbon atoms can be used.

The epoxy resin is a resin having two or more epoxy groups in one molecule. For example, glycidyl ether of polyphenol obtained by reacting polyphenol with epichlorohydrin is preferable. As polyphenols that can be used here, for example,
Bis (4-hydroxyphenyl) -2,2-propane,
Bis (4-hydroxyphenyl) -1,1-ethane, bis (4-hydroxyphenyl) -1,1-isobutane,
Bis (2-hydroxynaphthyl) -methane, bis (2
4-dihydroxyphenyl) -methane, tetra (4-hydroxyphenyl) -1,1,2,2-ethane and the like. Of these, the bisphenol type is preferred.

As the filler, one or two selected from those exemplified as the filler in the above-mentioned vinyl chloride resin-based paint are used.
More than species can be used.

In the polyurethane resin paint used in the coating method of the present invention, a urethane-modified polyester resin improves chipping resistance, and a block polyisocyanate compound and a melamine resin act as a curing agent. As a result, the balance between the flexibility and the curability of the coating film is excellent, and the film is sufficiently cross-linked and cured even at a temperature of 140 ° C. or less, and has good chipping resistance. Further, the epoxy resin improves the adhesion to the surface to be coated and also improves the chipping resistance.

The composition ratio of these components in the polyurethane resin-based coating is such that the total solid content of these components is 100% by weight, and the urethane-modified polyester resin is 50 to 7%.
0 wt%, blocked polyisocyanate compound is 5-2
It is particularly preferable that the content is 0% by weight, the melamine resin content is 10 to 30% by weight, and the epoxy resin content is 1 to 10% by weight. The filler is preferably in the range of 200 to 300 parts by weight per 100 parts by weight of the total solid content of the urethane-modified polyester resin, the block polyisocyanate compound, the melamine resin and the epoxy resin, and within this range, It is preferable because the chipping resistance, the sagging resistance of the coating film, and the prevention of the occurrence of wrinkles are improved.

The polyurethane resin paint used in the coating method of the present invention can be obtained by mixing and dispersing the above components in an organic solvent. As the organic solvent, one or more kinds selected from those exemplified as the organic solvent in the vinyl chloride resin-based paint can be used.

The polyurethane resin-based paint is coated on the uncured coating surface of the above-mentioned vinyl chloride resin-based paint by 5% based on the cured coating film.
It is preferable to apply a coating having a thickness of 0 to 100 μm by a coating method such as electrostatic coating, airless spray, or air spray.

In the coating method of the present invention, a predetermined portion of a chipping-resistant vinyl chloride resin coating and a polyurethane resin coating is applied by wet-on-wet, and then an intermediate coating is applied to the entire outer plate.

The intermediate coating is a liquid thermosetting coating comprising a base resin, a cross-linking agent and a pigment. As the base resin, for example, a hydroxyl group-containing polyester resin, a hydroxyl group-containing alkyd resin and the like are preferable. For example, amino resins such as melamine resins and urea resins are preferred. As the pigment, an ordinary pigment for paints can be used, and one or more kinds selected from those exemplified as the filler in the vinyl chloride resin-based paint can be used.

The intermediate coating is obtained by mixing and dispersing a base resin, a crosslinking agent, a pigment and the like in an organic solvent.
As the organic solvent, one or more kinds selected from those exemplified as the organic solvent in the vinyl chloride resin-based paint can be used.

The intermediate coating is applied on the entire surface of the outer plate including the uncured coating surface of the polyurethane resin coating based on the cured coating film.
With a film thickness of 0 to 20 μm, electrostatic coating, airless spray,
It is preferable to apply the coating by a coating method such as air spray.

According to the coating method of the present invention, a vinyl chloride resin paint, a polyurethane resin paint, and an intermediate paint are applied as described above, and the first colored paint is applied to a part of the uncured intermediate coat without curing. Paint.

The application site of the first colored coating does not need to coincide with the site where the chipping-resistant vinyl chloride resin-based coating or polyurethane resin-based coating is applied.
It is determined in consideration of the design of the tone finish, but usually,
It is preferable to apply the paint to the lower part of the vehicle body outer panel portion, and often overlaps the application portion of the chipping-resistant paint.

The first colored paint has a color tone different from that of the second colored paint, and contains a base resin, a cross-linking agent, a color pigment, and the like, and is obtained by mixing these with an organic solvent to obtain a thermosetting resin. Paint. As the organic solvent, one or more kinds selected from those exemplified as the organic solvent in the vinyl chloride resin-based paint can be used.

Examples of the base resin include an acrylic resin having a crosslinkable functional group, a polyester resin, an alkyd resin, and a urethane resin. Examples of the crosslinker include a melamine resin, a urea resin, a polyisocyanate compound, and a block polyisocyanate. Examples include isocyanate compounds. Further, as the coloring pigment, flake-like metallic pigments such as aluminum, stainless steel, and mica powder can be suitably used.

The first colored paint comprises the above-mentioned base resin, cross-linking agent, and color pigment, together with paint additives, if necessary.
It is obtained by mixing with an organic solvent, and this is generally applied to the lower part of the outer body of the vehicle body by 10 to 50 based on the cured coating film.
It is preferable to apply a coating having a thickness of μm by a coating method such as electrostatic coating, airless spray, or air spray.

In the coating method of the present invention, after the first colored coating is applied, the coating is heated at a temperature of about 100 to 170 ° C. for about 10 to 40 minutes to obtain the above-mentioned vinyl chloride resin coating, polyurethane resin coating, intermediate coating. The four-layer coating film composed of the paint and the first colored paint is simultaneously cross-linked and cured.

In the coating method of the present invention, the first colored paint is applied, cured by heating, and then the second colored paint is applied only to the upper portion of the vehicle body outer panel.

The second color paint is a thermosetting paint obtained by mixing a base resin, a cross-linking agent, a color pigment and the like with an organic solvent in a color tone different from that of the first color paint. As the organic solvent, one or more kinds selected from those exemplified as the organic solvent in the vinyl chloride resin-based paint can be used.

Examples of the base resin include acrylic resins, polyester resins, alkyd resins, and urethane resins having a crosslinkable functional group. Examples of the crosslinkers include melamine resins, urea resins, polyisocyanate compounds, and blocks. And polyisocyanate compounds. As the color pigment, flake-like metallic pigments such as aluminum, stainless steel, and mica powder can be suitably used.

The second colored paint is prepared by adding the above-mentioned base resin, cross-linking agent, and color pigment together with paint additives, if necessary.
It is obtained by mixing with an organic solvent.

In the coating method of the present invention, the first colored paint is applied, and the coated surface of the lower part of the body formed by heating and curing is masked with a masking tape or the like, and then the second colored paint is applied only to the exposed upper part of the body. Apply a coating method such as electrostatic coating, airless spraying, or air spraying to a thickness of 15 to 25 μm based on the cured coating film, and then cure the clear paint on the surface of the second colored paint without curing. 10 based on coating
Electrostatic coating, airless spray,
After coating by a coating method such as air spraying, the two coating films are cured by heating, whereby the coating method of the present invention is applied.
A tone finish is achieved.

As a result, the outer body of the vehicle body is made up of the first metallic paint and the second metallic paint having different metallic tones.
It is preferable that the coatings are applied in different colors and that the coating films of the two paints are in contact with and adjacent to each other, or are adjacent to each other via a molding or the like.

The clear paint to be applied to the second colored painted surface on the upper part of the vehicle body contains a base resin, a crosslinking agent and an organic solvent as main components,
Further, it is a liquid thermosetting paint which forms a colorless or colored transparent coating film containing a coloring pigment and other additives for coating materials to the extent that the transparency of the coating film is not impaired as required. Examples of the base resin of the clear paint include an acrylic resin having a crosslinkable functional group, a polyester resin, an alkyd resin, and a urethane resin. Examples of the crosslinker include a melamine resin, a urea resin, a polyisocyanate compound, and a block polyisocyanate. And the like. As the organic solvent, one or more kinds selected from those exemplified as the organic solvent in the vinyl chloride resin-based paint can be used.

After applying the clear paint, about 100 to 1
By heating at a temperature of 70 ° C. for 10 to 40 minutes, both coating films of the second colored paint and the clear paint are simultaneously cross-linked and cured.

[0051]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Production Examples, Examples, and Comparative Examples. All parts and percentages in each case are by weight.

Production Example 1 Preparation of Coating Material "Electron 9600" (trade name, epoxy resin-based cationic electrodeposition paint, manufactured by Kansai Paint Co., Ltd.) was electrodeposited on a steel plate for an automobile body so as to have a cured film thickness of 15 μm. Painted, 1
What was cured by heating at 60 ° C. for 30 minutes was used as an object to be coated.

Production Example 2 Vinyl chloride resin paint (a-
Preparation of 1) 100 parts of a vinyl chloride resin, 100 parts of a filler (titanium white, barium sulfate, calcium carbonate), 50 parts of a plasticizer (dibutyl phthalate), and a hydrocarbon solvent are blended, and a vinyl chloride resin paint (A-1) was prepared.

Production Example 3 Polyurethane resin paint (b-
Preparation of 1) Hexamethylene diisocyanate-modified polyester resin (hydroxyl value 90 mgKOH / g, number average molecular weight about 2,7
00) 60 parts, ε-caprolactam block hexamethylene diisocyanate 12 parts, “CYMEL 703” (trade name, melamine resin, manufactured by Mitsui Cyanamid Co.), 22 parts,
6 parts of an epoxy resin (“Epon 828”, manufactured by Shell Chemical Company, trade name, bisphenol type epoxy resin), 260 parts of a pigment (titanium white, barium sulfate), and a hydrocarbon solvent are blended, and a polyurethane resin paint ( b-1) was prepared.

Example 1 The vinyl chloride resin-based coating material (a-1) obtained in Production Example 2 was applied by airless spray coating to the lower part of the object to be coated obtained in Production Example 1 (coating thickness: 250 μm as a cured coating film). The polyurethane resin paint (b) obtained in Production Example 3 was applied to the uncured coated surface without curing.
-1) is applied by airless spray (the coating film thickness is 75 μm in a cured coating film), and without curing, “WSTP-65 Primer” (manufactured by Kansai Paint Co., Ltd., trade name, hydroxyl group-containing polyester resin / melamine resin middle coating) After coating the entire surface of the object with air spray coating (the coating thickness is 1
5 .mu.m), a portion of the above-mentioned polyurethane resin-based paint (b-1) coated without curing, as a first colored paint, "WSTP-069 silver" (manufactured by Kansai Paint Co., Ltd., trade name, hydroxyl group-containing polyester resin. Melamine resin-based silver metallic paint) was applied by air spray (the thickness of the coated film was 20 μm for the cured coating film), and then 30 ° C at 140 ° C.
By heating for a minute, these four-layer coatings were simultaneously cured. Next, after masking the coated surface of the first colored paint,
"NAD5500 B38M" (manufactured by Kansai Paint Co., Ltd., trade name, hydroxyl group-containing acrylic resin / melamine resin-based blue metallic paint) as a second colored paint is air-sprayed on the top of the object to be coated so as to be adjacent to the first colored paint film. After coating (the coating thickness is 20 μm with a cured coating film), without curing, further, as a clear paint, “DNC-K2 Clear” (trade name, manufactured by Kansai Paint Co., Ltd., hydroxyl group-containing acrylic resin / melamine resin clear paint) After applying air spray coating to the entire surface of the second colored paint portion (the coating film thickness is 40 μm as a cured coating film), the coating is heated at 140 ° C. for 30 minutes to simultaneously cure the upper two-layer coating film. Was carried out.

Comparative Example 1 A comparative coating method was performed in the same manner as in Example 1 except that the polyurethane resin-based coating material (b-1) was not used.

The performance of the coating films obtained in Example 1 and Comparative Example 1 was examined by the following test methods.

Adhesion between layers: A multi-layer coating film was cut at intervals of 1 mm with a cutter so as to reach a substrate, and the size was 1 mm ×
100 pieces of 1 mm squares were formed, an adhesive tape was stuck on the surface, and the adhesive tape was rapidly peeled off at 20 ° C., and the interlayer adhesion between the coating films was examined based on the number of remaining squares. ○
Represents 100 remaining, Δ represents 99 to 90 remaining, and X represents 89 or less remaining.

Chipping resistance: 500 g of No. 7 crushed stone was applied to a coated surface by using a gravelometer (manufactured by Q Panel Co., Ltd.).
It was sprayed onto the coated surface at an angle of ° and an air pressure of 0.3 MPa at 20 ° C to give an impact. Then, the state around the scratches due to impact after the adhesive tape was stuck to the coated surface and peeled off was examined. ○ indicates that the coating film peeling is hardly recognized around the scratch, Δ indicates that the coating peeling is clearly recognized around the scratch, and x indicates that the coating peeling is significantly recognized around the scratch.
Shown respectively.

Gloss: Evaluated by 60 ° specular reflectance (%).

Smoothness: The coated surface was visually evaluated. 5 indicates good smoothness, 4 indicates somewhat good smoothness, 3 indicates slightly poor smoothness but no problem in practical use, 2 indicates poor smoothness and is not practical, and 1 indicates very poor smoothness.

Color difference: Color difference meter “CR-20” manufactured by Minolta Co.
Using the “type 0”, the color difference (ΔE) from the color standard plate was determined. The smaller the numerical value is, the smaller the color difference is, and the better the value is 0.8 or less.

Table 1 shows the test results of the coating film performance.

[0064]

[Table 1]

The difference in the performance of the upper part in Table 1 is that the lower four-layer coating film and the spray dust exist in the lower part and the adjacent upper part, and the performance of the upper part film fluctuates due to the presence of the lower four-layer coating film and spray dust.

[0066]

According to the present invention, a vinyl chloride resin-based chipping resistant paint is applied to the lower portion of the outer body of the automobile body when the exterior body of the automobile body is painted in two tones. By applying the paint, it effectively prevents the decrease of the gloss of the first colored paint film, the disorder of the orientation when metallic pigment is contained, the decrease of the smoothness by the vinyl chloride resin paint, etc. As a result, a coating film having excellent finish appearance, chipping resistance and the like was formed on the outer panel of the automobile body.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kiminori Nakamura 1-1-1, Daihatsu-cho, Ikeda-shi, Osaka Inside Daihatsu Industry Co., Ltd. (72) Inventor Masao Yamaguchi 2-1-1 Taoyuan, Ikeda-shi, Osaka Daihatsu Inside Industrial Co., Ltd. (72) Inventor Hiromitsu Ine 2-1-1 Taoyuan, Ikeda-shi, Osaka Daihatsu Kogyo Co., Ltd. (72) Inventor, etc. 2-1-1 Taoyuan, Ikeda-shi, Osaka Daihatsu Kogyo Inside (72) Inventor Naoto Kubota 3-13-7 Nishitenma, Kita-ku, Osaka-shi, Osaka Inside Fan Trading Co., Ltd. (72) Inventor Ken Oi 3- 13-7, Nishitenma, Kita-ku, Osaka, Osaka Shares (72) Inventor Hideaki Fujiwara 33-1, Kanzakicho, Amagasaki City, Hyogo Kansai Paint Co., Ltd. (72) Inventor Masaru Minato 33, Kanzakicho, Amagasaki City, Hyogo Prefecture No. Kansai Paint Co., Ltd. in

Claims (1)

[Claims] 1. A method for coating an outer panel of an automobile body, which is finished to two tones using two kinds of colored paints having different color tones,
After coating the entire surface of the outer plate with an electrodeposition paint and curing by heating,
Apply a vinyl chloride resin-based chipping-resistant paint and polyurethane resin-based chipping-resistant paint to areas where gravel and pebbles are likely to hit, then apply an intermediate coating over the entire outer panel, and then apply Paint the first colored paint on the bottom,
After heating to cure these four-layer coatings at the same time, apply a second coloring paint and clear coating only to the upper part of the outer plate part, and heat to simultaneously cure these two-layer coatings on the upper part. A two-tone finish coating method characterized by the following.