JPS6193873A - Two-tone painting method - Google Patents

Abstract

PURPOSE:To obtain a good quality paint film showing high design effect, by applying a metallic base paint to an article to be painted after the completion of a series of processes such as under coating and subsequently applying a solid color paint to the specific area of the formed metallic base paint film and enclosing both paint films by a clear paint. CONSTITUTION:An electrodeposition paint film 2 as an under coat paint film and an intermediate coat paint film 3 are formed to the steel plate 1 constituting a car body. Next, a metallic base paint film 4 having a first color is at first formed to the selected area of the intermediate coat paint film 3 and solid color paint films 5, 5a each having a second color are formed to the part containing no metallic base paint film 4 and a part of the metallic base paint film 4. If a clear paint film 6 is smoothly formed to the entire surfaces of the two-tone paint films 4, 5, 5a as a finishing layer, a paint film inconspicuous in step difference, having gloss and excellent in weatherability and anti-staining property can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of painting an automobile body, and particularly to a method of applying two-tone painting to produce a new design effect.

[Conventional technology]

Various painting methods are used for painting automobile bodies, so-called exterior panels, etc. One of the typical painting methods is a method of applying solid color paint. Although this painting method has the advantage of being relatively simple and suitable for painting automobile bodies, due to the properties of the solid color paint itself, the resulting paint film is not glossy and the finish quality is poor. In other words, it has the disadvantage that the coating surface is not necessarily sufficient. Furthermore, this solid color coating film does not have sufficient weather resistance or light resistance, and tends to cause discoloration, discoloration, chalking, glossy pixelation, etc. during long-term use. Furthermore, this is particularly noticeable with paint colors such as super white, which are susceptible to the effects of atmospheric pollutants and gasoline, and are susceptible to stains caused by these substances.

Furthermore, methods of producing two-tone coatings using solid color paints are also known. This painting method usually involves applying a solid color paint over a metallic base paint coated with a clear coat. Although this coating method can produce a two-tone color design effect, it still has the disadvantages inherent to the solid color paints mentioned above, and due to the paint characteristics, the metallic base paint film and the solid color paint film are different. Adhesion is not good and layer peeling is likely to occur even at the initial stage of use.

Additionally, traditional two-tone painting methods also include common drawbacks. Two-tone painting usually involves finishing the lower layer (first paint color), drawing a parting line with masking tape, and then applying the upper layer (second paint color).
Finish by removing the masking tape.

However, in the case of this painting method, there is a problem with the large step in the upper layer (thickness bone) that is formed at the parting point when the masking tape is removed. The surface of the paint film is also rough to the touch, and if physical force is applied carelessly, layer peeling or chipping of the paint film may occur.In addition, if the thickness of the upper layer becomes particularly large, use tape or protector mold. This is because the parting line needs to be specially protected by such methods.Therefore, a two-tone painting method that does not create a large step at the parting part is desired.

In order to avoid the formation of steps in two-tone painting, a method of two-tone painting using tape decoration is known from Japanese Patent Publication No. 57-48273.

According to this painting method, after the tape covered by the cover is attached to the object to be painted, paint is applied on top of the tape, and
Then, by removing the cover from the tape, it is possible to eliminate the step-up in the parting part that was inevitable with two-tone painting, and at the same time, it is possible to improve the appearance of the attached tape. However, even with this improved method, it is not possible to avoid the disadvantages due to the above-mentioned characteristics when using solid color paints.

[Problem that the invention seeks to solve]

As is clear from the above facts, painting methods using solid color paints have various drawbacks, and these drawbacks also apply to two-tone painting methods using solid color paints. Therefore, it is now possible to avoid problems such as gloss, finish, weather resistance, light resistance, and staining that are inherent to solid color paints, and to prevent the solid color paint film from peeling off from the underlying paint film. It is possible,
The problem is to provide a two-tone coating method that can eliminate the sharp step difference at the two-tone boundary and can also lead to new design effects.

[Means for solving problems]

According to the present invention, the above-mentioned problems can be solved by applying a first coat to a selected area of an object to be coated, particularly an automobile body (outer panel, etc.), which has undergone a preceding painting process, such as an undercoating process or an intermediate coating process.
A metallic base paint with a paint color of Apply a solid color paint with a paint color of , bake and harden the formed paint film to obtain a solid color paint film, and then apply a clear paint to the entire surface of the metallic base paint film and the solid color paint film to make the painted surface smooth. This problem can be solved by a two-tone painting method, which is characterized by painting and curing it by baking.

〔Example〕

Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is an enlarged sectional view taken along line 1-1 of the automobile body after two-tone painting shown in FIG. From this figure, it can be seen that on the steel plate 1 that constitutes the car body, there are an undercoat film, that is, an electrodeposition (ED) film 2, an intermediate coat 3, and a metallic base coat of the first paint color. 4. It will be understood that the solid color coating 5 of the second coating color and the clear coating 6 as the finishing layer are applied in sequence. The illustrated coating system can be obtained, for example, through the following series of steps: First, as a pretreatment step, the prepared steel plate 1 is degreased and chemically treated to form a phosphate film (not shown). ) to form. Next, this phosphate film is coated with ordinary electrodeposition coating to a film thickness of approximately 1.
An undercoat film 2 of 5 to 20 μm is formed and cured by baking. Thereafter, in an intermediate coating step, a normal intermediate coating is applied to a film thickness of about 15 to 20 μm, and the resulting coating is baked and cured to obtain an intermediate coating 3.

After the formed intermediate coating film 3 is subjected to a polishing process such as hydroponic polishing or aerial polishing, a metallic base paint of a first paint color is applied to a selected area of the vehicle body 1 (here, the lower part of the vehicle body). Metallic base paints are, as is well known, dispersions of metallic pigments, such as aluminum flakes, and other pigments. The coating film thus formed is baked and cured to a thickness of about 10 to
A metallic base coating film 4 of 40 μm is obtained.

Subsequently, a masking step for forming parting lines is performed. This step can be advantageously carried out by applying suitable masking means, such as parting tape, masking paper, etc. (not shown) to the required portions of the previously formed metallic base coating film 4.

Under the above masking conditions, a solid color paint of the second paint color is applied to the non-masked areas of the vehicle body, that is, on the exposed intermediate coating film 3 and on a portion of the metallic base coating film 4. The solid color paint that can be used here is usually an amino, alkyd or polyester paint, and a solid color paint film 5 having a thickness of about 20 to 50 μm is obtained by curing the formed paint film by baking. In the illustrated case, since the intention is to form a two-tone parting line with thin lines, the thin lines 5a of the solid color coating film are also included. The thin wire 5a is a portion that is often prone to chipping or peeling in normal cases.

After the formation of the solid color coating is completed, the used masking means is peeled off. Next, a clear paint is applied to the entire surfaces of the metallic base paint film 4 and the solid color paint films 5 and 5a so that the painted surfaces are smooth. here,
Clear paints that can be advantageously used are those that are compatible in terms of physical properties such as adhesion to both the metallic base paint film and the solid color paint film to which they are applied, usually acrylic clear paints. For example, it will be useful as a rear paint,
One example is Super Rack-〇-28FI (product name) manufactured by Nippon Paint ■. This coating film is baked and cured in the same manner as in the previous step to form a clear coating film 6 with a film thickness of approximately 20 to 40 μm.
get.

〔Effect of the invention〕

According to the present invention, unlike the conventional two-tone painting method, there is no need to apply a solid color coating on top of a clear coating, so it is possible to avoid weakening the adhesion between coated coatings. . In other words, in the resulting coating system, there are no areas where the adhesion between the coatings is weak, so peeling and chipping of the coating can be prevented.

Furthermore, according to the present invention, the previously formed two-tone coating film is wrapped in a clear coating film, so that effects can be expected. Specifically, we will eliminate the defects observed in conventional solid color coatings and improve gloss, finish, and
Weather resistance, light resistance, stain resistance, etc. can be improved, and image clarity, etc. can be newly improved.

Further, according to the present invention, there is no sharp step difference in the two-tone parting part, and a good feeling can be obtained.

In addition, a new overall two-tone design effect can be expected. For example, by applying a clear coating film onto a two-tone coating film that is a combination of a solid color and a solid color, an unprecedented design effect can be obtained.

Furthermore, according to the present invention, a two-tone coating film can be obtained through a simple coating process.

[Brief explanation of the drawing]

1 is an enlarged sectional view taken along line 1-1 of the two-tone painted automobile body shown in FIG. 2, and FIG. 2 is a schematic side view of the two-tone painted automobile body. In the figure, 1 is a car body steel plate, 2 is an undercoat film, 3 is an intermediate coat film, 4 is a metallic base paint film, 5 is a Solirad color paint film, and 6 is a clear paint film.

Claims (1)

[Claims] 1. A method for applying two-tone painting to an automobile body, which comprises applying a metallic base paint of a first paint color to a selected area of the object to be painted after the preceding painting process has been completed. The resulting coating film is baked and cured to obtain a metallic base coating film, and a solid color paint of a second coating color is applied to a part of the object to be coated that does not include the metallic base coating film and a part of the metallic base coating film to form a metallic base coating film. A solid color coating film is obtained by baking and curing the resulting coating film, and a clear coating is applied to the entire surface of the metallic base coating film and the solid color coating film to make the coated surface smooth, and this is baking hardened. Two-tone painting method.