JPS618171A - Formation of embossed pattern and embossed body - Google Patents

Abstract

PURPOSE:To form a beautiful embossed surface by using a waste powdery paint, by such a relatively simple process that a powdery paint is electrostatically adhered to the surface of an article to be processed as a thick layer and difference of altitude is provided to the formed powdery paint film before baking. CONSTITUTION:After an electric field is provided between a powder painting apparatus 3 and an article 1 to be processed, a powdery paint 2 is electrostatically adhered to the surface of the article to be processed as a thick layer and, subsequently, treatment for providing difference of altitude, for example, by a spatula 4 is applied to said powdery paint film formed in an almost uniform thickness at this time while the treated paint film is baked to obtain an embossed surface. By this relatively simple process using a waste powdery paint, a beautiful embossed surface can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming an uneven pattern using a powder coating.

Attempts to coat surfaces such as metals using powdered plastic began about 50 years ago, and gradually developed as a means of plastic lining, especially after the development of powder electrostatic coating. , is rapidly penetrating into an extremely wide range of fields.

The characteristics of this electrostatic powder coating are: ■ There is no solvent loss during coating, and there is no danger of toxicity from organic solvents, photochemical pollution, or fire.

■ There is almost no loss of paint.

It is easy to collect and reuse the paint that does not adhere to the object to be coated, and by installing an appropriate collection device, it is possible to minimize the loss of paint during painting.

■ It is possible to rationalize the painting process.

A coating film with a wide range of thickness ranging from 50 to several hundred microns can be obtained in one coat, and thick coating of solution paint is difficult.
Paint film defects such as "sagging" and "foaming" are less likely to occur.

Furthermore, since painting can be easily automated, the painting process can be streamlined.

etc., and various shapes have been developed and utilized.

Also, regarding the field of use, for example, adhesion, toughness,
Epoxy resin powder coatings with excellent chemical resistance are widely used for electrical insulation coatings, the exterior coating of buried steel pipes, and the interior coating of automobiles, and are also used as top coatings on the exterior of automobile bodies where initial gloss is desired to be maintained. Acrylic resin-based and polyester-based powder paints, which have excellent weather resistance, are used for painting, decorative painting of home appliances, gates, fences, etc.

However, unlike solvent layer paints, the color of powder paints is determined at the time of paint manufacture, and even if paints of different colors are mixed, an intermediate color will not appear as with solvent layer paints, and the particles will be mixed. It has the disadvantage that it is baked as is, and it does not allow mixing of powder paints of different colors, let alone color toning.

Therefore, when handling multiple types of powder paint, it is necessary to have an independent powder paint recovery device for each color. If it is not collected in a timely manner, it will no longer be possible to reuse it. It is easy to imagine that even if individual collection equipment were prepared, a considerable amount of waste paint would still be generated.

Furthermore, since color matching is determined at the paint manufacturing stage and cannot be done by painting companies, paints of colors that are no longer manufactured are also likely to be disposed of.

The powder paint that was decided to be disposed of in this way cannot be easily disposed of because it is made of plastic particles.
Generally speaking, incineration disposal is commissioned to a specialist company at a high price. In other words, not only can it not be reused, but it also costs money to dispose of it.As these costs are added to the painting cost, electrostatic powder coating is currently an unnecessarily expensive painting method, especially when painting. This has become a serious problem for businesses.

Therefore, the inventor of the present invention started with the problem of effective utilization of powder paint which had become waste paint, and as a result of many years of intensive research, he finally achieved his goal in the field of uneven pattern formation.

In other words, the method for forming an uneven pattern, which is one of the aspects of the present invention, uses a powder coating and is a relatively simple process, while still retaining the advantages of the electrostatic coating method, which is known as a painting method. It is extremely innovative and groundbreaking.

To give an example of application to a metal plate, this uneven pattern formation is conventionally performed at the steel plate manufacturing stage by embossing or coining during rolling of the steel plate, or by pasting a processed synthetic resin sheet. There are methods such as etching and other post-manufacturing treatments for the steel material, but especially in high-productivity methods, either the stamping type or the etching method is expensive. On the other hand, the idea of pre-metal coating by embossing or coining negates the production of one-piece products with uneven patterns, and although it is useful for reducing production costs, it does not meet the wishes of all users. It was hard to say. In this sense, the present invention has been long awaited not only by businesses but also by consumers.

The present invention will be described in detail below based on the drawings.

The explanation will be given assuming the case of processing into a metal plate as a preferred example, but it is not limited to this, and can include all heat-resistant materials that can withstand temperatures higher than the melting temperature of the powder coating used. It is something.

Figure 1 shows the formation of uneven patterns (hereinafter referred to as "processing") using powder paint.
This figure shows a state in which a powder coating (2) is applied by electrostatic powder coating to the surface of a workpiece (1) to be coated.

This is because when a negatively ionized powder coating (2) is sent together with air from a powder coating device (3), the powder coating (2) is electrostatically charged to the workpiece (1), which is a positively charged body. This method is basically the same as the conventional painting method, but when used in the present invention, it is extremely large compared to the concept of normal painting. Powder paint (2) is applied to the desired thickness.

(For example, taking epoxy resin powder paint as an example, the film thickness in normal painting is said to be approximately 50 to 200 microns, but in the present invention, tests conducted at a film thickness of around 1 millimeter are optimal. At this stage, the powder coating (2) has adhered to the surface of the workpiece (11) with a uniform thickness.

Next (Fig. 2), the step of adding height differences to the powder paint (2) that has adhered to it due to static electricity begins. This was done by moving the waveform.

Subsequently, when the workpiece (1) with the surface having a height difference created in this way is baked at a temperature higher than the melting point of the powder coating (2) used, the workpiece (11) has a The paint is held and fixed while maintaining the height difference, and the uneven body (I2) of the present invention is completed.

If this uneven body (12) is made of a thermosetting resin-based (epoxy resin, etc.) powder coating, it will have excellent strength and an appearance that is no different from etching or embossing.
If a thermoplastic resin powder coating such as polyester or acrylic is used, the thick coating will result in foaming during baking, resulting in the formation of a very unique uneven pattern.

Up to this point, the formation of the uneven pattern has been completed in a strict sense, but in practice, electrical insulating coating, corrosion-resistant coating, decorative coating, etc. are then performed depending on the purpose of use.

Figure 3 (al and (bl) is an example of such a coating, which is one of the cosmetic coatings that has the effect of highlighting the unevenness caused by processing.

First, a shading powder paint (5) darker than the metal color (for example, brown color) is electrostatically applied to the surface of the uneven body (12) that has been powder coated in a metal color (for example, copper color) and baked. Attach to target. ((a) in the same figure) Next, lightly brush the surface with a brush or the like.As is clear from (b) in the same figure, the surface of the uneven body (12) of the powder coating for shading (5) The distribution is no longer uniform, with less on the convex portions (6) and more on the concave portions (7).As a result, the unevenness is accentuated, and in addition, fine hairlines (brush lines) caused by brushing are The eyes) will have an extremely deep and beautiful finish.The resulting product will be fired again to create the finished product.

Alternatively, the surface may be further coated with a transparent paint or the like.

An example of the present invention has been shown above, and the surface of the workpiece (1).

Various modifications can be considered in the process of adding height differences to the powder coating (2) attached to the surface, and some of them will be shown below.

Fig. 4 shows a system in which a spatula (4) having a corrugated end surface is moved by a reciprocating device (8) as a piston, and a workpiece (1) is placed on a conveyor (9) and is continuously processed. It is. This reciprocating device (8) and spatula (4)
Depending on the shape, it seems possible to draw quite a variety of patterns.

Figure 5 shows how powder paint (2) is removed by suction nozzle (10).
The idea is to create a pattern while sucking in the water. In this case, the powder coating (2) is not sequentially brought to the surrounding area to form the recesses as in the previous case, so it is easier to apply the powder coating thickly (i.e., the particles collapse into piles). ), and the unevenness becomes very clear. Moreover, if the suction nozzle (10) is connected to an industrial robot and operated, it is expected that it will be possible to draw something with a certain degree of design.

Finally, Fig. 6 shows a baking process in which a masking material (11) is placed on the surface of the workpiece (11) in advance, powder paint (2) is applied, and then the masking material (11) is removed. The plan is to move to .

Although various other methods may be possible, the method in which powdered synthetic resin is electrostatically attached to the surface of the workpiece and then processed by creating irregularities on the surface before baking is All are included in the present invention.

Furthermore, although the workpiece Tl) has been described so far as a metal plate, it is also possible to apply the present invention to wood products and plastic products with low electrical conductivity by using a chemical that imparts electrical conductivity. However, it can be applied not only to plate materials but also to almost anything that can be electrostatically powder coated, such as finished products such as pipes and boxes.

Further, unlike general painting, the purpose of the present invention is to depict unevenness, so even if a powder coating made of a material that foams during baking is used, it is possible to obtain a unique uneven body.

As explained in detail above, the present invention provides an electrostatic The powder coating is applied thickly to the surface of the workpiece, and the powder coating film of almost uniform thickness that is formed at this time is treated to create height differences, and then baked to create an uneven surface. With this uneven pattern forming method, it is possible to turn the waste powder coating, which was generated in large quantities at each business office and had a problem of disposal, into a material for forming a beautiful uneven surface. Depending on the nature of the paint, it is possible to depict a variety of unique objects such as hard, metallic objects and foaming objects, and it is also easy to produce, making it an extremely innovative product that is especially suitable for small-lot, high-mix products. It is an invention.

[Brief explanation of drawings]

1 and 2 both show an example of the uneven pattern forming method of the present invention, and FIG. 1 is a schematic front view to show the principle;
FIG. 2 is a perspective view, FIG. 3(a) is a partially enlarged perspective view showing a state in which powder coating for shading is further adhered to the uneven body of the present invention, and FIG. FIG. 3 is a cross-sectional view of a product whose surface has been brushed. FIG. 4, FIG. 5, and FIG. 6 are perspective views showing other embodiments of the present invention. 1...Workpiece 2...Powder coating 3...
Powder coating device 4... Spatula 5... Powder coating for shading 6... Convex part -7... Concave part 8.
... Reciprocating device 9 ... Conveyor 10 ...
・Suction nozzle 11... Masking material 12...
Uneven body construction times 13 Yo Biao 2 stomach [b] inferior 6

Claims (1)

[Claims] 1. After providing an electric field between the powder coating device and the workpiece,
The powder coating is electrostatically adhered thickly to the surface of the workpiece,
Next, the powder coating film of substantially uniform thickness formed at this time is subjected to a treatment to provide height differences, and then baked to obtain an uneven surface. 2. The method for forming an uneven pattern according to claim 1, wherein the treatment is performed by adhering the powder coating to the workpiece and then moving a spatula while contacting the workpiece. . 3. The treatment is carried out by attaching the powder paint to the workpiece, then bringing a suction nozzle into contact with the workpiece, and removing the powder paint from the contacted area.Claim 1 The uneven pattern forming method described in Section 1. 4. The treatment is carried out by placing a masking material on the surface of the workpiece in advance, applying a powder coating, and then removing the masking material before baking. The uneven pattern forming method described above. 5. After baking the powder coating, powder coatings of different colors are attached to the surface of the workpiece, and the coating is baked again by brushing with a brush or the like.Claims 1 and 2 , the method for forming an uneven pattern according to item 3 or 4. 6. An uneven body having an uneven layer made of powder paint on its surface. 7. The uneven body according to claim 6, wherein the surface of the uneven layer is further coated with an overcoat.