JP2999105B2 - Painting method of building board and building board with spot pattern - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method for applying a coating having a spot pattern on a surface to be coated of a building board such as a fiber cement board, and to a building board with a spot pattern.

[0002]

2. Description of the Related Art It is very preferable in terms of design to apply a speckled coating to an architectural board such as a fiber cement board to give an appearance like a natural stone. Conventionally, in order to apply such a spotted pattern coating on a building board, the viscosity and thixotropy of the paint are set within a predetermined range, and the moving speed of the spray gun with respect to the coated surface and the discharge amount from the spray gun,
Further, there is provided a method in which the diameter of a spray pattern or the like on the surface to be coated is set within a predetermined range, and the paint is sprayed from the spray gun onto the surface to be coated in a state where the paint is not atomized or almost not atomized ( JP-A-3-157160, JP-A-3-157
-186381).

[0003]

However, according to the above-mentioned conventional method, the paint is sprayed from the spray gun onto the surface to be coated in a state where the paint is not atomized or almost not atomized. moving speed of the gun, the discharge amount from the spray gun, it is necessary to adjust the diameters many factors of the spray pattern slightly, in particular the width I wide
The painting of a building board having a surface to be coated required enormous labor, and the nozzle of the spray gun was easily clogged, and the probability of defective products was high.

[0004]

According to the present invention, as a means for solving the above-mentioned conventional problems, the rotational speed of the nozzle (3) of the bell type coating machine (1) is set to 300 to 2500 m / min.
Provided is a coating method for coating a surface to be coated by dispersing a coating material having a viscosity adjusted to 30 to 80 cps / 25 ° C., and further provides a building board with a spot pattern and a multicolor spot pattern coated by the coating method. It provides building boards.

[0005]

The paint used in the present invention may be any of a water-based paint and an oil-based paint, and the viscosity is usually 30 to 80.
It is adjusted to cps / 25 ° C. A bell type coating machine is a coating machine mainly used for painting the body of an automobile, and sprays and atomizes paint from a rotating nozzle by centrifugal force to electrostatically paint an object to be coated. The rotation speed of the nozzle at this time is usually 4700 to 7900 m /
Set to the range of minutes. In the present invention, the rotation speed of the nozzle of the bell-type coating machine is set to be much lower than the normal rotation speed, and the peripheral speed is set in the range of 300 to 2500 m / min. In this range, the paint is dispersed in particles coarser than the atomization and adheres to the surface to be coated. The size of the paint particles at this time becomes smaller as the nozzle rotation speed becomes higher. If the nozzle rotation speed exceeds 2500 m / min, the paint is dispersed in a mist state, and as a result, the surface to be coated is uniformly applied and does not become a spot. When the nozzle rotation speed is less than 300 m / min,
It is difficult to disperse the paint in the form of particles.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to an embodiment shown in FIGS. 1 to 4. In FIG. 1, (1) is a bell-type coating machine, and is composed of a machine frame (2) and a machine frame (2). a nozzle (3) which is rotatably mounted to the lower direction to the tip, the air motor (4) for rotating the nozzle (3), the shaving air cap attached to the upper side of the nozzle (3) (3E ), The air motor (4) and the shaving air cap
(3E), high-pressure air is sent from the operation panel (6) through the air feed passages (7, 8), respectively, and a paint supply passage from the paint tank (9) is provided at the root end of the nozzle (3). The paint (5) is supplied by the pump (11) via (10), and the excess paint (5) is returned to the paint tank (9) via the return path (12).

The nozzle (3) has a structure as shown in FIG. 2, for example, and has an outer frame (3) having a slit (3 B) stretched in the opening.
A paint supply port (3C) communicating with the paint supply path (10) is provided at the root end of (A), a dispersing plate (3D) is arranged immediately below the paint supply port (3C), and the outer frame (3A As shown in FIG. 3, a shaving in which small blow holes (31E) having a diameter of, for example, 0.5 mm and large blow holes (32E) having a diameter of, for example, 1.0 mm are substantially alternately arranged in a circle at the root end. Air cap (3E) is attached.

In the bell type coating machine (1) having the above configuration, the nozzle (3) is rotated by the air motor (4), and the paint (5) is supplied from the paint supply port (3C) into the nozzle (3). The paint (5) is centrifugally applied to the paint (5) by a dispersion plate (3D) to be dispersed in a granular form, and is sprayed on the surface to be coated through a slit (3B). At this time, the shaving air cap (3E)
E, 32E) blows air downward to regulate the spread of paint particles.

The bell type coating machine (1, 1) is disposed, for example, directly above a belt conveyor (14) for moving a plate (13A) to be coated in an arrow direction as shown in FIG.
4) Coating is applied to the upper plate (13A). At this time, the rotation speed of the nozzle (3) of the bell type coating machine (1) is set to 300 to 2500.
The spot-like coating is performed by setting the range to m / min. The coated plate (13) after coating is transferred to a roller conveyor (15) and transferred to a drying step. Then, on the lower side of the belt conveyor (14), the paint adhered is washed by the washing liquid in the washing tank (16).

In the above-mentioned coating system, a multicolor spot pattern can be formed by changing the color of the paint used for the bell-type coater (1) in the first stage and the bell-type coater (1) in the second stage. Also, three or more bell-type coating machines (1) may be set.

Table 1 shows the results when the water-based paint was applied to the fiber cement board by the above-mentioned coating system.

[Table 1]

According to Table 1, the paint viscosity is 35 cps / 25.
When the nozzle rotation speed is less than 300 m / min, even at 75 ° C./25° C., even if the nozzle rotation speed is less than 300 m / min, the coating is not smoothly granulated, and the coating becomes coarse and massive. It will be painted.

[0013]

Accordingly, in the present invention, a building having a wide surface to be coated can be obtained only by adjusting the rotation speed of the nozzle of the bell type coating machine.
Speckled paint for built plate is very easily carried out, the quotient
An architectural board with a speckled pattern like a natural stone with extremely high product value can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 4 show one embodiment of the present invention.

[Fig. 1] Painting system diagram

FIG. 2 is a sectional view of a nozzle.

FIG. 3 is a bottom view of a shaving air cap.

Fig. 4 Painting process diagram

[Explanation of symbols]

 1 Bell type coating machine 3 Nozzle 4 Air motor 13A Plate to be coated 13 Painted plate

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigeharu Shirai 12 Nishiha, Minato-ku, Nagoya-shi Nichiha Co., Ltd. (56) References JP-A-54-163978 (JP, A) JP-A-3-186381 (JP) JP-A-4-300665 (JP, A) JP-A-63-114635 (JP, A) JP-B-63-47511 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB B05D 1/02 B05D 5/06 101 B32B 13/12 E04F 13/08 E04F 13/14 102

Claims (3)

(57) [Claims] 1. The nozzle rotation speed of a bell type coating machine is 300 to
Set to 2500 m / min to increase viscosity from 30 to 80 cps / 25
A method for painting a building board, characterized in that the surface of the building board is painted by dispersing a paint adjusted to a temperature of ° C. 2. The nozzle speed of a bell type coating machine is 300 to 300.
Set to 2500 m / min to increase viscosity from 30 to 80 cps / 25
Architectural board with spots, characterized in that the surface is painted by dispersing a paint adjusted to ℃ 3. The building board with a spot pattern according to claim 2, wherein the spot pattern is multicolored.