JPS62132572A - Diverse painting method - Google Patents

Abstract

PURPOSE:To permit easy control of a paint and to reduce painting installations by using the same metallic paint for the paint of the 1st color and the paint of the 2nd color and changing the painting conditions thereof so that diverse painting can be made with one kind of the paint. CONSTITUTION:The surface of a material 1 to be coated on which a a primer coat 3 or the primer coat 3 and an intermediate coat 4 are successively applied is subjected to the diverse painting by using the paint 5 of the 1st color and the paint 10 of the 2nd color. The same metallic paint is used for the paints 5, 10 and the painting is executed by changing the painting conditions for the 1st color and the painting conditions for the 2nd color. The painting conditions in this case refer to the pressure of atomizing air, the pattern width of the paint, the distance for spraying, impressed voltage, the discharge quantity of the paint, etc., in the case of, for example, painting by an air atomization electrostatic painting method. As a result, the diverse painting is made possible with one kind of the paint, by which the control of the paint is made easy and the painting installations are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of separately painting the surface of an object to be painted, such as an automobile body, using the same metallic paint.

[Conventional technology]

2. Description of the Related Art Conventionally, when the surface of an object to be painted, such as an automobile body, is to be painted separately, it has been carried out by a painting method as shown in the sectional view of FIG.

In FIG. 3, reference numeral 50 denotes an object to be painted made of a metal material. First, a chemical conversion coating 51 is formed on the surface of the object 50 to improve adhesion, and then an undercoat is applied by an appropriate coating method. A film 52 and an intermediate coating film 53 are sequentially formed.

Next, a first color top coat is applied to the surface of the intermediate coat 53 to form a first top coat 54.

After baking and curing this first top coat film 54, a parting tape 56 is affixed to the parting part 55 from the next top coat paint, and this parting strip 15
6 and the first top coat film 54 side are masked with a masking material 57 such as paper.

In this state, a second color topcoat having a different color and composition from the first color topcoat is applied to the area below the masking to form a second topcoat film 58. After baking and curing the second top coat 58, the masking material 57 is removed and the parting tape 56 is peeled off.

As a result, the first top coat film 5 is applied to the surface of the object 50 to be coated.
4 and the second top coat 58 are formed, and the separate painting is completed.

[Problems to be Solved by the Invention] However, in such a separate painting method, two types of paint, a first color topcoat and a second color topcoat, are used to perform separate painting. As a result, not only is paint management complicated, but there are also problems in that it requires painting equipment, painting space, and other painting facilities.

Therefore, this invention was made to solve the above-mentioned problems, and by using the same metallic paint as the first color paint and the second color paint, and changing the coating conditions, one type of paint can be used. The object of the present invention is to make it possible to perform separate coatings, to facilitate the management of paints, and to reduce the need for painting equipment.

[Means for Solving the Problems] That is, in the separate painting method according to the present invention, the first color paint is applied to the surface of the object to be painted, which has been sequentially coated with the uncoated paint, the undercoat paint, and the intermediate coat paint. When painting separately using the paint of the first color and the second color,
The paint of the same color and the paint of the second color are the same metallic paint, and the coating conditions for the first color and the coating conditions for the second color are changed.

The painting conditions here include, for example, when painting with an air atomization electrostatic painting method, the atomization air pressure, paint pattern width, spraying distance, applied voltage, paint discharge amount, etc.
In the case of painting using the air atomization painting method, it refers to all painting conditions except for the applied voltage in the air atomization electrostatic painting method. When painting with the rotary atomization static 11 painting method, the number of rotations of the bell,
Applied voltage, amount of paint discharged, spraying refers to distance, etc.

Furthermore, the relationship between the coating conditions and brightness of metallic paint is as follows.

In other words, in the air atomization electrostatic painting method, the lower the atomizing air pressure, the narrower the paint pattern width, the shorter the spray distance, the higher the applied voltage, and the greater the amount of paint discharged, the more the paint will be formed. The brightness of the paint film decreases, and by applying the opposite coating conditions, the brightness of the paint film formed increases.

The air atomization coating method is also the same as the air atomization electrostatic coating method except for the applied voltage. Furthermore, regarding the rotary atomization electrostatic coating method, the lower the bell rotation speed, the higher the applied voltage, the greater the amount of paint discharged, and the shorter the spraying distance, the lower the brightness of the paint film formed. By applying coating conditions opposite to these, the brightness of the coating film formed increases.

[Effect]

In such a separate painting method, the same metallic paint is used and the coating conditions for the first color and the second color are changed to perform separate painting, so the orientation of the metallics contained in the paint is different for both. This changes depending on the coating conditions, and the receiving angle of the rays of light that are reflected on the painted film surface and enters the visual field differs.

By the way, metallic paint contains disc-shaped or scale-shaped aluminum and pigment, and depends on the viewing angle, that is,
There is a phenomenon in which the visually perceived brightness differs depending on the receiving angle of the emitted light reflected by the painted film surface.

Therefore, even though the first color paint film and the second color paint film have different receiving angles of the light rays that enter the visual field and are painted with the same metallic paint, their lightness is different, so they have different color tones, that is, paint films of the second color are painted with the same metallic paint. This gives you different tones.

〔Example〕

Hereinafter, the separate painting method according to the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples (and various modifications may be made without departing from the gist of the present invention). Of course, it is possible to add

(First Example) FIG. 1 is a process diagram illustrating a first example of the separate painting method according to the present invention.

In Figure 1, ■ is l, 000 x 3.000 x 0.8
Tsuru cold rolled steel plate (JIS-G~3141.5PCC)
This test piece was treated with a pretreatment process consisting of alkaline degreasing, water washing, zinc phosphate treatment, and water washing, and then heated at 80°C for 10
The sample was drained and dried in a drying oven for a minute to form a zinc phosphate film 2 of 8 g/g on the surface of the test piece 1, as shown in FIG. 1(a).

Next, the entire test piece 1 was coated with a polybutadiene-based anionic electrodeposition paint, and after washing with water, it was baked and cured in a drying oven set at 160°C for 30 minutes to obtain an average film thickness of 25 μm. An undercoat film 3 was formed.

Subsequently, the entire test piece 1 was coated with air atomization using the intermediate coating paint and coating conditions shown below to form an intermediate coating film 4.

(1) Intermediate coating (a) Composition (parts by weight) (i) Epoxy resin: 30 parts (b) Titanium oxide pigment: 30 parts (c) Carbon black: trace amount (d) Organic solvent: 40 parts ('b) Viscosity = 22 to 23 seconds (Ford Cup #4/23°C) (c) Paint color: Gray (2) Painting conditions <a>egm: Devilbiss air atomization spray gun (b) Paint discharge rate : 300m#/m1n(C)
Paint pressure: 1.5kg/cn (d) Air pressure: 5. Okg/cfl! (e) Pattern width: 30 cm/φ (f) Spraying distance: 30 CIl (3) Paint film thickness: 30 μm Test piece 1 on which intermediate coating film 4 was formed was set at a furnace temperature of 140°C. Bake for 30 minutes in a drying oven.
hardened.

The entirety of the obtained test piece 1 was subjected to air atomization electrostatic painting using a top coat mixed with metallic 5a and under the coating conditions shown below to form a first color top coat 1 [5].

(1) Top coat (a) Composition (parts are parts by weight) (a) Acrylic/melamine resin: 15.00 parts (b)
Aluminum foil: 2.00 parts (c) Cyanine blue: 0.20 parts (d) Carbon black: 0.02 parts (e) Organic solvent
: 82.78 parts (b) Viscosity: 13 to 1
4 seconds (Ford Cup #4/23°C) (c) Paint color Nibble (2) Painting conditions (a) Painting machine Niunsburg spray gun (b) Atomization air pressure: 3. Okg/cII! (C
) Spraying distance i1i H3Qcm (d) Pattern width
740cm/φ <e) Paint discharge amount: 80 Qm6/m1n(f)
Applied voltage: eoKv 3) Coating film thickness: 15 μm After setting the obtained test piece l in a setting chamber at a room temperature of 30°C for 10 minutes, it was coated with the clear paint shown below without baking or curing. Air atomization electrostatic coating was performed depending on the conditions to form a clear coating film 6a.

(1) Clear paint (a) Composition (parts by weight) (a) Acrylic/melamine resin: 40 parts (b) Organic solvent 260 parts (b) Viscosity: 26 seconds (Ford Cup #4/23°C ) (C) Paint color: Colorless and transparent (2) Painting conditions Same as the painting conditions of the first color topcoat paint.

(3) Paint film thickness: 30 μm After setting the obtained test piece 1 in a setting room at a room temperature of 30°C for 10 minutes, this test piece 1
in a drying oven with an internal temperature of 140°C.
The colored top coat 5 and clear coat 6a were baked and cured for 30 minutes.

Subsequently, as shown in FIG. 1(C), a parting tape 8 is pasted to the parting part 7 of the clear coating film 6a of the test piece 1, and a part of this parting strip 8 and the clear parting tape 8 are attached to each other. The coating film 6a is masked with paper 9.

In this state, air atomization electrostatic painting was performed on areas other than the masking area using the top coat paint and the coating conditions shown below to form the top coat film 10 of the second color.

(1) Top coat paint The same as the top coat paint that formed the first color top coat film 5.

(2) Coating conditions Same as the coating conditions for the first color top coat except that the atomization air pressure was 5.0 kg/al.

(3) Coating film thickness: 15 μm After setting the obtained test piece 1 in a setting room at a room temperature of 30°C for 10 minutes, a coating film was formed on the surface of the first color topcoat III 5 without baking or curing. Air atomization electrostatic coating was performed using the clear paint and coating conditions to form a 30 μm clear paint film 6b.

Furthermore, test piece 1 was coated with a second color topcoat MIJILO in a drying oven with an oven temperature set at 140°C.
The clear coating film 6b was baked and cured for 30 minutes.

After that, remove the masking paper 9 and
The parting strip 8 was peeled off.

As mentioned above, in the first embodiment, the same metallic paint is used and the atomizing air pressure for the first color and the atomizing air pressure for the second color are changed to perform separate painting.
As shown in d), the orientation of the metallic 5a of the first color topcoat film 5 and the second color topcoat film 10 changes, and the reception angle of the light beam reflected from the paint film surface and entering the visual field differs.

Therefore, the first color topcoat film 5 and the second color topcoat film 10, which have different reception angles of light rays entering the visual field, are different because of their different lightness even though they are coated with the same metallic paint. A blue tone, that is, a divided color tone is obtained.

(Second Example) FIG. 2 is a process diagram illustrating a second example of the separate painting method according to the present invention.

In Figure 2, 11 is 1,000X3,00OX0.
8m (7) cold rolled steel plate (J l5-G-3141,5
PCC), this test piece 1 is treated with a pretreatment process consisting of alkaline degreasing, water washing, zinc phosphate treatment, and water washing.
Figure 2 (a) after draining and drying in a drying oven for 10 minutes at °C.
As shown in the figure, a zinc phosphate coating 12 of 7 g/n was formed on the surface of the test piece 11.

Next, the entire test piece 11 was electrodeposited with a polybutadiene-based anionic electrodeposition paint, washed with water, and baked and cured in a drying oven set at 160°C for 30 minutes to obtain an average film thickness of 25 μm. An undercoat film 13 was formed.

Next, as shown in Fig. 2(b), test piece 1
1 was subjected to air atomization electrostatic painting using a top coat mixed with metallic 14a and under the coating conditions shown below to form a top coat 14 of the first color.

(1) Top coat (a) Composition (Parts are @Okibe) (a) Acrylic/melamine resin: t6. Part o (b) Aluminum foil: 1.5 parts (c) Nickel titanium yellow: Part o (d) Carbon blank:
0.1 part (e) Organic solvent: 82.3 parts (
b) Viscosity: 13 to 14 seconds (Ford Cup #4/23°C) (C) Paint color: Yellow (2) Painting conditions The spraying distance was the same as in the first example except that the distance was 20 gloss. Same painting conditions as the first color top coat.

(3) Paint film thickness: 15 μm After setting the obtained test piece 11 in a setting room at a room temperature of 30°C for 10 minutes, it was air atomized using the clear paint and coating conditions shown below without baking or curing. A clear coating film 15 was formed by electrostatic coating.

(1) Clear paint Same as the clear paint of the first example.

(2) Painting conditions The coating conditions are the same as the coating conditions for the first color top coat in the first example.

(3) Coating film thickness: 30 μm After setting the obtained test piece 11 in a setting room at a room temperature of 30°C for 10 minutes, this test piece 11 was placed in a drying oven whose internal temperature was set at 140°C. ,
The first color top coat 14 and clear coat 15 were baked and cured for 30 minutes.

Next, as shown in Figure 2 (C), test piece 1
A parting tape 17 is affixed to the dividing part 16 of the clear coating film 15 of No. 1, and this parting strip 17 is
A part of the clear coating film 15 is masked with paper 18.

In this state, air atomization electrostatic painting was performed on areas other than the masking area using the top coat paint and the coating conditions shown below to form a second color top coat film 19.

(1) Top coat of the first color] Same as the top coat that formed 4.

(2) Coating conditions The coating conditions were the same as those for the top coat of the first color in the first embodiment, except that the paint was sprayed at a distance of 50 sprays.

(3) Coating film thickness: 15 μm After setting the obtained test piece 11 in a setting room at a room temperature of 30°C for 10 minutes, the surface of the top coat 14 of the first color was Clear coating film 2 of 30μm depending on the formed clear coating and coating conditions.
0 was formed.

Furthermore, the test piece 11 was baked and cured for 30 minutes with the second color top coat 19 and clear coat 20 in a drying oven with an oven temperature set at 140°C. After that, while removing masking II and 18,
The parting strip 17 was peeled off.

As mentioned above, in the second embodiment, the same metallic paint is used, and the spraying distance of the first color paint and the distance changing the spraying distance of the second color paint are applied separately. As shown in (d) of the figure, the top coat film 1 of the first color
The orientation of the metallic 14a of the top coat 19 of the fourth and second colors changes, and the receiving angle of the light beam reflected from the paint film surface and entering the visual field differs.

Therefore, although the first color topcoat film 14 and the second color topcoat film 19, which have different reception angles of light rays entering the visual field, are coated with the same metallic paint, they are different because their lightness is different. A yellow tone, that is, a divided color tone is obtained.

〔Effect of the invention〕

As explained above, in the separate painting method according to the present invention, the first color paint and the second color paint are the same metallic paint, and the coating conditions are changed, so that one type of paint is used. Since it is possible to perform separate coatings, it is possible to manage the paint more easily than with conventional separate coatings, and the cost of painting equipment can be significantly reduced.

Further, in the separate painting method according to the present invention, since separate painting can be performed using the same paint, there is an effect that the cost of separate painting can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a process diagram illustrating a first embodiment of the separate coating method according to the present invention. FIG. 2 is a process diagram illustrating a second embodiment of the separate coating method according to the present invention. FIG. 3 is a cross-sectional view illustrating a conventional separate painting method. ■・----・Test piece 3-----First undercoat film 4----First coat paint film 5-----First color topcoat film 53--・-Metallic 10- --- Second color top coat applicant Toyota Motor Corporation] --- Test case 5-- One rate IT! , ¥3oh hope! ζ (a) (b)
Figure 1 Figure 3

Claims (1)

[Claims] When applying a first color paint and a second color paint to the surface of the object to be coated, which has been sequentially coated with an undercoat paint or an undercoat paint and an intermediate coat paint, the first color paint and the second color paint are applied separately. A separate painting method characterized in that the same metallic paint is used as the paint of the same color, and the coating conditions of the first color and the second color are changed.