JPH0459951B2 - - Google Patents

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 outer panels, and the like. One of the typical painting methods
One method is to apply 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 lacks gloss 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, yoking, gloss blurring, 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 color (first paint color), and then drawing a parting line with masking tape after that.
Furthermore, the upper layer (second coating color) is finished, and the masking tape is finally peeled off to complete the process. However, in the case of this coating method, there is a problem in that a large step corresponding to the thickness of the upper layer is formed at the parting portion when the masking tape is peeled off. This is because such steps not only look bad visually, but also make the paint surface feel bad to the touch, and if physical force is applied carelessly, it can cause layer peeling or chipping of the paint film. This is because when the thickness of the upper layer becomes particularly large, it is necessary to specially protect the parting line with tape or protecta mold. Therefore, there is a need for a two-tone painting method that does not create a large step difference in the parting area.

In order to avoid the formation of steps in two-tone painting, a method of performing two-tone painting using tape decoration is known from Japanese Patent Publication No. 57-48273. According to this method of painting, the tape covered by a cover is attached to the object to be painted, the paint is applied over these, and then the cover is removed from the tape, thereby avoiding the problem of two-tone painting. By eliminating the need for tiering at the high parting portion, the appearance of the attached tape can also be improved. 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 attempts to solve]

As is clear from the above facts, there are various drawbacks to the painting method using solid color paints, and these drawbacks also apply to the two-tone painting method using solid color paints. Therefore, it is now possible to prevent the solid color paint from peeling off from the underlying paint without causing problems such as gloss, finish, weather resistance, light resistance, and staining, which are the inherent disadvantages of solid color paint. The problem is to provide a two-tone coating method that can prevent such problems, eliminate sharp steps at two-tone boundaries, and bring about new design effects.

[Means for solving problems]

According to the present invention, the above-mentioned problems can be solved by applying a first coating 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 of the paint color is applied, the formed paint film is cured by baking to obtain a metallic base paint film, and a second coat is applied to a part of the object to be coated that does not contain the metallic base paint film and a part of the metallic base paint film. A solid color paint is applied, the formed paint film is cured by baking to obtain a solid color paint film, and a clear paint is applied to the entire surface of the metallic base paint film and the solid color paint film so that the painted surface is smooth. This problem can be solved by a two-tone coating method characterized by baking and hardening.

〔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 segment - of the automobile body after two-tone painting shown in FIG. From this figure, it can be seen that on the steel plate 1 constituting the car body, an undercoat film, that is, an electrodeposited (ED) film 2,
It can be seen that the intermediate coating film 3, the metallic base coating film 4 of the first coating color, the solid color coating film 5 of the second coating color, and the clear coating film 6 as the finishing layer are sequentially applied. Probably. The illustrated coating system is
For example, it can be obtained 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). Next, this phosphate film is subjected to ordinary electrodeposition coating to form an undercoat film 2 having a film thickness of approximately 15 to 20 μm, and this is baked and hardened. After that, in the intermediate coating process, a regular intermediate coating is applied to a film thickness of 15 to 20 μm.
The intermediate coating film 3 is obtained by baking and hardening the obtained coating film.

After the formed intermediate coating film 3 is subjected to a polishing process such as water polishing or air polishing, a metallic base paint of a first paint color is applied to a selected area of the vehicle body 1 (in this case, the lower part of the vehicle body). Metallic base paints are well known dispersions of metallic pigments, such as aluminum flakes, and other pigments. The coating film thus formed is cured by baking to obtain a metallic base coating film 4 having a thickness of about 10 to 40 μm.

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 4.

Under the above masking conditions, a solid color paint of the second paint color is applied to the unmasked areas of the vehicle body, ie, on the exposed intermediate coating 3 and on a portion of the metallic base coating 4. Solid color paints that can be used here are usually amino, alkyd or polyester paints. The formed coating film is then cured by baking to obtain a solid color coating film 5 having a thickness of about 20 to 50 μm. 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
This is a part that is often prone to chipping and peeling under normal circumstances.

After the formation of the solid color coating is completed, the used masking means is peeled off. Next, metallic base coating 4 and solid color coatings 5 and 5 were applied.
Apply clear paint to the entire surface of a so that the painted surface is smooth. Here, the clear paint that can be advantageously used is one that is compatible in terms of physical properties such as adhesion with both the metallic base paint film and the solid color paint film to be coated, usually an acrylic clear paint. It is. As a useful clear paint, for example, Super Lacku-O- manufactured by Nippon Paint Co., Ltd.
I can give you 28M (product name). This coating film is baked and hardened in the same way as in the previous process to a film thickness of approximately 20 to 40μ.
A clear coating film 6 of m is obtained.

〔Effect of the invention〕

According to the present invention, unlike the conventional two-tone painting method, it is not necessary to apply a solid color paint film on top of a clear paint film, so it is possible to avoid weakening of the adhesion between overcoated paint films. I can do it. 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, since the previously formed two-tone coating film is wrapped in a clear coating film,
We can expect the effects of this. Specifically, we will eliminate the defects observed in conventional solid color coatings and improve gloss, finish, weather resistance, light resistance,
It is possible to improve stain resistance, etc., and to newly improve image clarity, etc.

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 onto a two-tone coating consisting of a solid color plus 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 drawings]

FIG. 1 is an enlarged cross-sectional view of the two-tone painted automobile body shown in FIG. 2 along the line segment 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 solid color paint film, and 6 is a clear paint film.

Claims (1)

[Claims] 1. A method for applying two-tone paint to an automobile body, which comprises applying a metallic base paint of a first paint color to a selected area of a workpiece that has completed a preceding painting process to form a two-tone paint. A metallic base coating film is obtained by baking and curing the 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. A solid colored coating film is obtained by baking and hardening the painted 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 baked and hardened. Two-tone painting method.