JP2549026B2 - Matte coating method using thermosetting resin paint - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel matte coating method for thermosetting paints.

[0002]

2. Description of the Related Art Thermosetting resin paints are used under severe conditions such as outdoors because they are excellent in various performances as paints such as adhesion, water resistance, weather resistance and stain resistance. Used for painting building materials and other products. In particular, among thermosetting resin paints, acrylic resin paints include solvent-based paints and emulsion-based paints, which are widely used for various purposes. Therefore, the present invention is also described based on the acrylic resin paint, but it is not limited to this.

Acrylic resin paints have a unique luster,
There are various coatings that make use of this luster, but on the other hand,
There are cases where it is desired to have a low gloss, so-called matte state, while maintaining the performance as a paint. Therefore, the following two are mainly performed as conventional matte coating methods. (1) A method of increasing the mixing ratio of the coloring pigment and the extender pigment in the paint. (2) A method of spraying and adhering fine powder such as sand or glass powder.

In the method (1), the proportion of the extender pigment increases when the thickness of the paint layer is constant, but the proportion of the resin that controls the properties of the paint layer decreases, resulting in durability and weather resistance of the paint layer. On the contrary, in order to maintain durability and weather resistance, the thickness of the paint layer must be increased, and when the substrate has an uneven pattern, the unevenness becomes unclear and the expression of the pattern is expressed. Becomes defective.

In the case of the method (2), there is a problem that a spraying device for fine powder is required and the appearance of the sprayed product is restricted. It is difficult to use for painting.

[0006]

SUMMARY OF THE INVENTION The present invention aims to obtain a dull matte gloss appearance by applying a thermosetting resin coating, generally an acrylic resin coating, to an exterior material having an embossed pattern. That is the subject.

[0007]

In order to solve the above-mentioned problems, the present invention provides, as the first method, as described in "Claim 1", "a cement-based inorganic substrate (1) is coated with a thermosetting resin coating ( 2) is applied almost uniformly, the thermosetting resin paint (2) is heated to melt the resin, and then the thermosetting resin paint is applied in the form of fine particles (5) in an amount of 5 to 15 g / m ^2. After that, it is heated and dried ”.

As the second method, as described in "Claim 2", " Cement-based inorganic substrate (1) is thermosettable".
When the resin coating material (2) is applied almost uniformly, and the thermosetting resin coating material (2) is heated to melt the resin but before it flows, the thermosetting resin coating material is applied. Is applied in the form of fine particles (3) in an amount of 5 to 15 g / m ² and then dried by heating ”.

[0009]

According to the present invention, since the paint layer is integrated with the paint layer surface formed on the cement-based inorganic substrate, a myriad of microscopic projections composed of paint particles are formed.
A low gloss matte coated surface is obtained.

[0010]

The present invention will be described below. The thermosetting resin coating material used in the present invention is usually an acrylic resin coating material. The building materials to be painted are mainly cement-based exterior materials such as ALC.

The coating method according to the first invention will be described in detail. (1) The substrate (1) is uniformly coated with an acrylic resin-based coating material. This coating is applied once or twice or more times to form a coating layer (2) having a predetermined thickness. (2) Next, the paint layer (2) is heated. By this heating, the solvent of the paint layer (2) volatilizes first, and then the resin melts (3) Furthermore, the resin of the paint layer (2) flows and then hardens by being heated. In the invention, the acrylic resin paint is made into fine particles (3) in this fluid state,
It is applied on the surface of the paint layer (2) at a rate of 5 to 15 g / m ² , and then heated again. (4) Therefore, innumerable protrusions are formed by the coating fine particles (3) on the smooth coating layer. Since the paint layer (2) is in a fluidized state before being cured, the paint particles (3) are adhered and integrated. By heating after this, the paint layer (2) hardens, but when further heating is applied, the paint particles (3) that form the convex parts flow and the convex parts of the coated surface disappear and become smooth, resulting in a glossy surface. Therefore, the paint particles (3) adhere to the surface of the paint layer (2) because of the appearance of the paint particles, and the paint particles (3) need to maintain the convex portion and finish the heating before the fluidized state. . (5) The coating layer (2) on which the convex portions are formed is hardened without flowing in order to finish heating in a molten state while maintaining the convex portions, and as a result, the coated surface having innumerable convex portions Is obtained,
A coated building material with a matte, dull and glossy appearance is obtained.
An arbitrary matte coating surface as shown in FIG. 1 can be easily obtained depending on the particle size and the degree of heating of the paint particles (3).

The second invention, like the first invention, is a substrate (1).
The acrylic resin paint (2) is evenly applied to the above, and then the paint layer (2) is heated to a molten state. Then this paint layer
Although the resin of (2) is in a molten state, the acrylic resin coating material is applied in the form of fine particles (3) at 5 to 15 g / m ² before flowing. Then, since the paint layer (2) is temporarily cooled by the fine particle paint (3), the paint layer (2) hardens as it is without flowing.

The coating layer (2) of the second invention thus formed looks smooth in a coated state, but microscopically, due to uneven coating or the like, a concave portion or a convex portion is formed on the surface of the coating layer (2). However, since the paint layer (2) does not flow, it cures as it is. On the other hand, the paint fine particles (3) adhere to the molten paint layer (2) to form innumerable protrusions, and as a result, the paint layer
The coated surface has an infinite number of protrusions integrated with (2). If the paint layer (2) is overheated at this stage, the innumerable convex parts formed by the paint particles (3) will flow and flatten, so it is important to finish the heating before fluidizing. Is. Therefore, in this case, as shown in FIG.
A matte coated surface having a lower gloss than the coated surface of the first invention can be obtained.

Example 1 An acrylic resin emulsion paint was applied to a cement-based substrate having an embossed pattern twice by a flow coater at a rate of 60 g / m ² , followed by heating with a Schwang burner for about 120 seconds, and then, The same acrylic resin emulsion paint fine particles were sprayed by air spray at a rate of 10 g / m ² and heated at 120 ° C. for 50 seconds.

(Example 2) The same procedure was carried out except that the heating time of the Schwang burner of Example 1 was changed to 90 seconds.

(Comparative Example 1) Comparative Example 1 was the same as Example 1 except that granular coating was not performed.

(Comparative Example 2) 60 g / m ^{2 of the} same acrylic resin emulsion paint as in (Example 1) was applied to a cement substrate having an embossed pattern, and then 60 g of a commercially available low-gloss acrylic resin emulsion paint. It was applied with a flow coater at a ratio of / m ² and heated under the same conditions as in (Example 1). The test results of these products are as follows

The results are shown in Table 1.

[0017]

[Table 1] The surface gloss is measured by a Murakami specular reflectometer. Chalking is a phenomenon in which the coating film ages due to sunlight, wind and rain, etc., and then becomes powdered from the coating surface, which is a stage before whitening.
Efro is a phenomenon in which white crystals form on the concrete surface.

[0018]

As described above, in the first and second aspects of the invention, the pigments and other additives are not used in the paint, but the fine particles of the paint originally used are used. A low-gloss appearance can be obtained without decreasing the performance of the paint layer without increasing the layer thickness. In addition, even if the paint layer has a low gloss, it is possible to prevent the occurrence of eflation peculiar to cement products, and since the paint layer is thin, the embossed pattern on the substrate can be expressed sharply. Furthermore, since the same base paint and matte paint can be used, the number of paint types can be reduced, and since there is no solid content such as pigments, the coating equipment is not clogged and the quality is stable. . in addition,
Since the fine-grain paint is sprayed, the coating amount used for the matte granular coating is small, and the matte coating can be produced at a low cost.

[Brief description of drawings]

FIG. 1 is a sectional view of a building material formed by the present invention, which corresponds to claim 1.

FIG. 2 is a sectional view of a building material formed by the present invention, which corresponds to claim 2;

[Explanation of symbols]

 (1) ... Substrate (2) ... Thermosetting paint layer (3) ... Paint fine particles

Claims (2)

(57) [Claims] 1. A thermosetting tree cementitious inorganic substrate
Substantially uniformly coating the fat coating, and heating the thermosetting resin coating the resin in a molten state, then, after 5 to 15 g / m ² coated with a thermosetting resin coating material in particulate, heating drying A matte coating method using a thermosetting resin coating characterized by: 2. A thermosetting tree cementitious inorganic substrate
When the oil paint is applied almost uniformly and the thermosetting resin paint is heated to melt the resin but before it flows,
A matte coating method using a thermosetting resin coating, which comprises applying 5 to 15 g / m ^{2 of the} thermosetting resin coating in the form of fine particles and then heating and drying.