JPH0389972A - Painting method - Google Patents

Abstract

PURPOSE:To prevent the generation of a recessed pit on a painting finish surface due to the moisture absorption or drying of a base material by forming a bottom coat layer to a base material and subsequently applying shape processing thereto before forming a top coat layer. CONSTITUTION:After a bottom coat layer 2 is formed to one surface and side surface of a base material to which rough processing is applied, for example, a hole 5 is formed to the base material 1 and a top coat layer 6 is subsequently formed to the surface of the bottom coat layer 2 and the inner peripheral surface of the hole 5. Since the exposed surface of the base material 1 is covered with the top coat layer 6 by this method, the base material 1 generates no moisture absorption or drying and a problem generating unevenness on a painting finish surface is not generated. Further, by making the film of the top coat layer 6 thin after shape processing is applied, a problem bringing about trouble in the assembling with a plastic part by the accumulation of paint at a corner part, that is, a problem caused by the lowering of shape accuracy is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for painting wooden products, and particularly to a method that satisfies the accuracy of the shape of the wooden products and the durability at the same time.

"Conventional technology" Traditionally, there have been methods for manufacturing wood products by cutting, grinding, and painting wood, which requires less viscosity during processing to form the external shape of the wood product. Shape machining of parts that are not processed (hereinafter referred to as rough machining)
After this, shape processing (hereinafter referred to as precision processing) is performed on parts that require precision, such as parts where plastic parts are assembled. Next, after forming an undercoat layer consisting of a colored layer and an intermediate coat layer on the wood processed in this way, there is a method of forming a second coat layer, or after rough processing the wood, an undercoat layer and a top coat are applied. There is a method of forming layers and then performing precision processing.

``Problem to be solved by the invention'' However, in the former case, the paint film is formed after precision machining, so the paint accumulates in some corners, for example, and a thick paint film is formed, which may cause damage to the plastic in the subsequent process. This creates the problem of not interfering with assembly with parts, etc., that is, the accuracy of the shape decreases.

In addition, in the latter case, the above-mentioned problem of reduced shape accuracy is caused by undamaged or precisely processed parts of the wood that are exposed, and the wood absorbs moisture and dries from these parts. It may cause unevenness on the painted surface around the exposed area, which may cause problems in terms of appearance. Furthermore, if the wood absorbs moisture and dries under harsh conditions, there is a risk that the surrounding painted surface may crack or crack. In order to solve such problems,
``1.A method of applying moisture-proof coating to the exposed surface has been proposed, but the problem arises that this moisture-proof coating is time-consuming and expensive, and furthermore, it is difficult to apply moisture-proof coating to the exposed surface. This may cause problems such as paintability, such as protruding onto the exposed surface and worsening the appearance.

"Means for Solving the Problems" In the present invention, the problems described in - are solved by forming an F coating layer on a base material, performing shape processing, and then forming an overcoat layer.

"Function" By shaping the base material on which the undercoat layer has been formed and then applying coating to this base material, the exposed parts of the base material exposed by the shape process are covered with the paint layer, so that the base material It does not absorb moisture or dry out.

Therefore, paintability J: However, problems such as unevenness do not occur. In addition, by thinning the paint layer, which is formed after applying pressure to the shape, we can solve the problem of preventing paint from accumulating in some corners and causing problems when assembling plastic parts, etc. No problems arise due to a decrease in straw shape accuracy.

Hereinafter, the wood coating method of the present invention will be explained in detail.

FIGS. 1 to 10 are process diagrams showing an example of the method for painting water conservancies according to the present invention.

Reference numeral 1 in FIG. 1 indicates a base material. This base material 1 can be made of a natural wood board or an artificial wood board. , composite boards laminated to core materials such as synthetic wood cement, and even FRP.
Plastic side materials such as Nato are used.

Next, as shown in FIG. 2, this base material 1 is subjected to rough processing to form an external shape. Next, as shown in FIG. 3, an undercoat layer 2 is formed on the surface and side surface of the roughly processed base material 1. Here, it is preferable that the surface of the substrate 1 is previously subjected to grinding or cutting before the undercoat layer 2 is formed, and for this grinding, sandpaper of about #180 to #400 is used. As shown in an enlarged view in FIG. 4, it may consist of a colored layer 3 and an intermediate coating layer 4, but it is not limited to this, and for example, one or more coating layers may be provided between the colored layer 3 and intermediate coating layer 4. A film may be formed, or a colored layer 3 may be formed or not. Here, this intermediate coating layer 4
is mainly responsible for properties such as the strength of the entire coating film and the durability of the coating.

The colored layer 3 is coated with a colorant 5 of an appropriate color, or is patterned with an appropriate printing method. The coloring agent may be a dye or pigment dissolved in a solvent, or a small amount of a resin, such as a polyurethane resin, dissolved therein, and applied by brushing or spraying. Further, as the printing method, methods such as graphia printing, screen printing, and offset printing are used.

- On the other hand, for the intermediate coating layer 4, for example, epoxy resins, unsaturated polyester resins, acrylic resins, polyurethane resins, sialyl phthalate 1-based resins, and mixtures thereof are preferably used. It is not limited to this. Further, additives such as a light stabilizer, an antioxidant, and a crosslinking agent may be added to this resin as appropriate.

The method for applying the resin is not particularly limited, but air spray, flow coater, electrostatic spray, or brush coating methods are preferably used.

After forming the undercoat layer 2 in this way, as shown in FIGS.
As shown in the figure, a hole 5 is formed approximately at the center of the surface of the substrate 1. Since plastic parts and the like are assembled into this hole 5 in the rear stage, precision is required in its shape.

After this precision machining has been carried out, a two-coat layer 6 is applied to the surface of the undercoat layer 2 and one hole 5, using a two-coat paint.
is formed on the inner circumferential surface of the This state can be seen in Figures 8 to 1.
Shown in Figure 0. For this top coat layer 6, paints of full gloss, half gloss, half gloss, etc. are used depending on the required finishing condition. Also, since this "second coat layer 6" requires IIIFI paint, the paint forming this "second coat layer 6" needs to be a paint film or a moisture-resistant paint.
For example, urethane-based or unsaturated polyester-based paints are preferably used. The method of applying such a paint is not particularly limited, and it can be applied by any known method as in the case of the undercoat layer 2.

In the present invention, since the topcoat layer 6 is also applied to areas where shape precision is required, the thickness of the topcoat layer 6 needs to be thin. Look at 6 and defend! Since there are some parts that exhibit l-λ, it is necessary to have a film thickness that does not impair the moisture-proof properties of the coating film. Therefore, the thickness of this top coat layer 6 is preferably about 2011 m to 100 μm.

On the other hand, since the intermediate coating layer 4 is thinner than the coating film of the top coating layer 6, it is necessary for the intermediate coating layer 4 to maintain the physical properties such as strength and durability of the coating film. Therefore, the intermediate coating layer 4 has a coating density of 200
It is preferable that the film thickness is at least am.

In addition, in the cow-dressing method of the present invention, as a method other than the above-mentioned example, for example, after forming the undercoat layer 2, rough processing and precision processing are performed, and then a second coating layer 6 is formed. Good too.

"Example" (Example 1) As the base material 1, as shown in FIG. Phenol-cured Nos. 1 to 9.9 are arranged on the outer surface of the phenolic adhesive sheets 8.8, and further, the phenol-cured adhesive sheet 8 is arranged on the outer surface of the phenol-cured sheet 9 on the front side,
A walnut veneer 10 is placed on the outer surface, and this
The material was bonded with pressure at 40° C. for 0 minutes, 1 hour, and OMP a.

After the base material 1 was rough-processed to form an external shape, its surface and side surfaces were ground with #240 paper (FIG. 2).

The side surface of this ground surface machining was first colored with an aqueous coloring agent, and then colored with a urethane paint and color matched to form a colored layer 3. The thickness of the colored pressing layer after drying (hereinafter, the thickness is referred to as the value after drying) was about 5 μm, and the thickness of the color matching layer was about 10 μm.

Next, an intermediate coating was applied to the surface of the colored layer 3 with an unsaturated polyester paint to form an intermediate coating layer 4 having a thickness of about 600 μm. After drying this intermediate coating layer 4, it was finished by grinding with a #400 blade paver (FIGS. 3 and 4).

Holes 5 were formed in the substrate 1 on which the undercoat layer 2 was formed (FIGS. 5 to 7). Here, since plastic parts will be assembled into the hole 5 in a later process, this hole 5
is a part that requires shape accuracy. Next, a non-wax type unsaturated polyester paint was applied to form a top coat layer 6 on the surface of the intermediate coat layer 4 and the inner peripheral surface of the holes 5 (FIGS. 8 to 10). After this second coating layer 6 was dried, it was abraded with #600 sand paper, and then finished by hough polishing.

The coated product obtained in this way has a thick intermediate coating layer 4, so the intermediate coating layer 4 maintains the strength and surface abrasion properties of the coating at the same level as ordinary coated products. It sank. Also,
After forming the thick intermediate coat layer 4, holes 5 are formed which require precision in shape, and the top coat layer 6 applied after the holes 5 are formed is thin. So,
The accuracy of the shape of the holes 5 was good. Furthermore, since the top coat layer 6 was also formed on the inner circumferential surface of the hole 5, the wood did not absorb moisture or dry and did not cause unevenness on the painted surface.

(Example 2) After forming an undercoat layer 2 consisting of a colored layer 3 and an intermediate coat layer 4, rough processing is performed, and the second coat layer 6 is coated with a urethane-based semi-gloss clear paint, and this film is Thickness is 3
Coating was carried out in the same manner as in Example 1 except that the thickness was 0 μm. In this example, only the top coat layer 6 was coated on the side surface of the substrate 1 and the inner peripheral surface of the hole 5 exposed by rough processing.

Similarly to the coated product obtained in the first embodiment, the coated product formed by this method also has good precision in the shape of the holes 5, and since there is no exposed surface of the wood, the wood may absorb moisture or dry out. It didn't smudge, and there were no uneven surfaces on the painted surface.

"Effects of the Invention" The present invention is a coating method characterized by forming an undercoat layer on a base material, applying shape pressure, and then forming an overcoat layer. By processing the shape and then applying a topcoat to this base material, the exposed parts of the base material are covered with the topcoat layer, so the base material does not absorb lH or dry out, and it is possible to create gate protrusions on the painted surface. Problems such as whether it will survive or not. In addition, by thinning the paint layer that is formed after shape processing, there are problems such as paint buildup in some corners etc., which interferes with adhesion to plastic parts, etc. No problems arise due to a decrease in shape accuracy.

[Brief explanation of drawings]

1 to 10 show an example of the coating method of the present invention in the order of steps, and FIGS. 1, 2, 5, and 8 are schematic plan views, and FIGS. 3, 4, Figure 6, Figure 7, Figure 9
Figures 1 and 10 show schematic cross-sectional views. Moreover, FIG. 11 is a schematic cross-sectional view showing a substrate used in an example of the present invention. ■ ・ Base material, 2 ・ Undercoat layer 6
Two coats.

Claims (1)

[Claims] A coating method characterized by forming an undercoat layer on a base material, subjecting it to shape processing, and then forming an overcoat layer.