JP2003136017A - Coating method of porous plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove a coating material turning around to the back face of a porous plate at the time of applying the coating material to the front face of the porous plate. SOLUTION: The coating method of a porous plate (ALC plate) is for coating the front face of a porous plate during transportation process from a step of taking in the porous plate to a step of taking out the plate and involves coating steps 102 and 104 of forming a coating liquid film on the front face of the ALC plate by blowing a water-proof coating material by pressure to the front face of the ALC plate and a removal step 105 of removing the coating material turning around to the rear face of the ALC plate by washing with a brush.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coating a porous plate, and more specifically, to a porous plate having irregularities or bubbles on its surface (for example, lightweight cellular concrete, hereinafter simply referred to as ALC plate or ALC plate). It is also referred to as an outer wall material.) The present invention relates to a coating method for a porous plate, which has a step of coating a waterproof coating on the surface of the outer wall material.

[0002]

2. Description of the Related Art Conventionally, as an outer wall of a building, there have been many outer walls such as a soil wall coated with soil, etc., which have been constructed at a construction site. The outer wall, in which the timber is attached to the outer wall of the building, has been widely used because it can be constructed quickly, uniformly, and with good appearance.

As the outer wall material produced in the factory, ALC is used.
Outer wall material made of (Autoclaved Light-weight Concrete), outer wall material made of precast concrete, and outer wall material made of hard wood cement board.

[0004] In particular, ALC outer wall materials are produced in large quantities because they are similar in appearance to precast concrete outer wall materials and are light and easy to construct. As an outer wall material of a building such as a house, a material having a recently engraved concave-convex pattern has been favored by construction workers because of its luxurious appearance.

A coating material is usually applied to the surface of such an outer wall material in order to improve its appearance and prevent it from absorbing water. Conventionally, as a coating method for coating the surface of such an outer wall material, there are a brush coating method, a spray coating method, a roll coater, a flow coater, a dipping method, and the like.

The brush application method is the most primitive method, in which the surface of the outer wall material is stroked and applied with a brush to which a paint is attached. This brush application method is suitable for repairing the coating surface of small quantities of outer wall materials and outer wall materials because the brush is put in the paint reservoir, the paint is attached to the brush, and this brush is stroked to apply. However, since it is not suitable for mass production, it is not used in the mass production process of outer wall materials.

On the other hand, the spray coating method is a method of spraying paint from a nozzle at the tip of the spray and spraying the sprayed paint on the surface of the outer wall material to paint. The air spray method and the airless spray method are used. There is. The air spray system consists of a compressed air passage leading to the nozzle at the tip of the spray gun and a passage leading from the paint reservoir to this compressed air passage. When compressed air is passed through the nozzle at the tip, the compressed air passage is decompressed, the paint in the paint reservoir is sucked through the passage leading to the compressed air passage, and the sucked paint and air are combined. This is the method of painting from the nozzle.

In the airless spray system, a passage is provided from the paint reservoir to the nozzle at the tip of the spray gun. When compressed air is introduced into the paint reservoir, the pressure of the compressed air causes This is a method in which the paint is pushed out into the passage and the paint is blown out from the nozzle at the tip of the spray gun. Since this spray coating method can spray the paint on the surface of the outer wall material, it can be applied to a deeply carved outer wall material, and is used for coating various outer wall materials.

After airless spray painting,
A combination coating method is used, such as a method in which excess paint is scraped off with an air knife that produces an air jet in the shape of a slit, or a method in which an air jet is applied in a pressure booth after passing through a pressure reduction booth after spray painting.

However, even if the conventional spray coating method, which is considered to be the most effective method for coating the surface of the outer wall material, there are many problems in coating the outer wall material made of ALC with deep engraving. Was occurring. That is, if there is a deep engraving such as a groove, there is a problem that the amount of coating material applied by spraying is different between the groove portion and the non-groove portion.

Further, in the case of the ALC outer wall material, many bubbles appear on the surface at the time of manufacture to form fine holes (irregularities).
When paint is applied to this surface by the spray method, the inside of the unevenness is not applied, and the inside of the unevenness contains an air reservoir, and the air reservoir is ruptured after the coating liquid film is formed, and that portion is painted. No coating or thin coating liquid film.

Further, in the method of removing paint by an air knife after spray painting or by making the paint into a uniform thin film in a decompression booth + a pressure booth, the paint pool such as grooves is reduced, but the paint liquid film reaches inside the bubbles. There is a problem that it cannot be formed.

ALC having a coating liquid film formed on a conventional surface
When a part of the plate is schematically illustrated, for example, as shown in FIG. 9A, when the coating liquid film 2 is formed by coating the surface of the ALC plate 1 with a waterproof coating device, Inside the large number of air bubbles 3 present on the surface of the plate 1, air is contained in the coating liquid film 2
The air reservoir 5 was formed in a sealed state by.

However, when the pore diameter of the bubble 3 is large,
As shown in FIG. 9B, when the air pressure changes with the passage of time, the air reservoir 5 in the bubble 3 expands and bursts, causing a pinhole 4 in the coating liquid film 2. there were.

As one of the measures for solving such a problem, it is conceivable to apply a coating liquid film thickly. However, in this case, a large amount of paint (coating composition) is required, and the solution is There were still problems such as inadequacy. FIG. 10 schematically shows a state in which the coating liquid film 2 having an extremely large thickness is formed on the surface of the ALC plate 1.

Therefore, the applicant of the present invention should spray the paint onto the surface of the porous plate under pressure to push the paint into the air bubbles provided on the surface of the porous plate to reduce the pressure of the coating liquid film surface of the porous plate. Then, a coating method has been developed in which the air reservoir trapped in the bubbles is expanded and ruptured to form a coating liquid film.

[0017]

Here, in the above-mentioned coating method, a coating process line is constructed in which the porous plate is sequentially conveyed from the carry-in process to the carry-out process, and the porous plate is subjected to coating work on the way. For mass production,
The following problems may occur.

That is, if the porous plates after coating are stacked and sequentially stacked and stored, the upper and lower porous plates will stick together due to the influence of gravity, temperature, time, etc. If so, a defect that the surface of the porous plate is damaged (hereinafter referred to as blocking defect) has occurred.

The cause of this is that the paint is applied to the surface of the porous plate and the paint is blown by air, so that when the paint is applied to the surface of the porous plate with a substantially uniform thickness, the air pressure of the air blow is increased. It was found that the paint on the front surface wraps around to the back surface due to the influence of, and the porous plates that are conveyed as they are are sequentially stacked and stored.

[0020]

In order to solve the above problems, therefore, the method for coating a porous plate according to the present invention is a method for coating a porous plate while the porous plate is being conveyed from the loading process to the unloading process. In the one that has the process of painting the surface,
A step of spraying a paint on the surface of the porous plate under pressure;
It has a step of removing excess paint on the surface of the porous plate by air blowing, and a step of removing the paint sneaking around the back surface of the porous plate while cleaning with a brush. .

According to this coating method, when the surface of the porous plate is sprayed with the paint under pressure and the excess paint is removed by air spraying, the paint wraps around to the back surface of the porous plate. Since there is a step of brush cleaning and removing the paint, even if the porous plates after coating are stacked and stored in the storage section, the paint that wraps around the back surface causes the upper and lower porous plates It is possible to prevent problems such as sticking.

In addition, after the step of brush-cleaning and removing the paint that has flowed around the back surface of the porous plate, the step of drying the porous plate and the powdery material forming the porous plate are used. And a step of spraying powder on the surface of the porous plate.

According to such a coating method, the paint that has flowed around the back surface of the porous plate is removed by brush cleaning, the porous plate is dried, and then the material forming the porous plate is used. In a state in which the powdered powder is sprayed on the surface of the porous plate, the porous plates after coating are stacked and stored in the storage portion, so that the powder is not present between the upper and lower porous plates. By interposing it, it is possible to prevent the occurrence of a defect such as the upper and lower porous plates sticking to each other.

Further, the method for coating a porous plate according to the present invention comprises a step of applying a coating to the surface of the porous plate during the transportation of the porous plate from the loading step to the unloading step. A step of spraying paint on the surface of the plate under pressure, a step of removing excess paint on the surface of the porous plate by air spraying, and an abutting portion for abutting the paint wrapping around the back surface of the porous plate Is used to scrape off the coating material.

Further, according to the coating method, since there is a step of scraping the coating material wrapping around the back surface of the porous plate at the contact portion, the porous plates after the coating are overlaid. Even if they are stacked and stored in the storage section in the above state, it is possible to prevent the occurrence of a problem in which the upper and lower porous plates are stuck to each other due to the coating material that has wrapped around the back surface.

In addition, after the step of scraping the coating material wrapping around on the back surface of the porous plate at the contact portion, the step of drying the porous plate and the material forming the porous plate are made into powder. And a step of spraying powder on the surface of the porous plate.

According to such a coating method, the coating material wrapping around the back surface of the porous plate is scraped off at the contact portion, the porous plate is dried, and then the material forming the porous plate is used. In a state in which the powdered powder is sprayed on the surface of the porous plate, the porous plates after coating are stacked and stored in the storage portion, so that the powder is not present between the upper and lower porous plates. By interposing it, it is possible to prevent the occurrence of a defect such as the upper and lower porous plates sticking to each other.

Further, in the step of scraping off the coating material that has flown around the back surface of the porous plate by the abutting portion, the leaf spring-shaped abutting portion arranged at the conveyor level position of the porous plate by the conveyor is concerned. The coating material is scraped off by bringing it into contact with the back surface of the porous plate.

Further, according to the coating method, when the porous plate is conveyed, the plate spring-shaped contact portion contacts the back surface of the porous plate at the conveyance level position by the conveyor. The paint can be scraped off by a simple structure such as disposing the contact portion.

Further, the method for coating a porous plate according to the present invention comprises a step of applying a coating on the surface of the porous plate during the transportation of the porous plate from the loading step to the unloading step. The step of spraying the paint on the surface of the plate under pressure, the step of removing the excess paint on the surface of the porous plate by air spraying, and the paint sneaking around the back surface of the porous plate are removed while brush cleaning And a step of scraping off the paint by using an abutting portion that comes into contact with the paint wrapping around the back surface of the porous plate.

According to such a coating treatment method, even if there is paint that has sneak up on the back surface of the porous plate that cannot be removed only by brush cleaning, the paint can be scraped off by the contact portion. Therefore, the paint on the back surface can be reliably removed.

Further, after the step of removing the coating material wrapping around the back surface of the porous plate by the brush cleaning and scraping the coating material wrapping around the back surface of the porous plate at the contact portion, the porous plate is cleaned. It is characterized by including a step of drying and a step of spraying a powder of a material forming the porous plate on the surface of the porous plate.

According to such a coating method, the coating material sneaking around the back surface of the porous plate is brush-cleaned, and the contact portion is brought into contact with the coating material to remove the coating material. It can be made more stable, and further, after the porous plate is dried, the powder of the material forming the porous plate is applied to the surface of the porous plate in a state of being coated with powder. Since the porous plates that have been completed are stacked and stored in the storage unit, the risk of causing a problem such as the upper and lower porous plates sticking to each other can be further reduced.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for coating a porous plate according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing the outline of a coating process line to which the present invention is applied.

Reference numeral 100 denotes a carry-in process for carrying in the porous plate 11 (hereinafter referred to as an ALC plate) supplied from the material storage site into the coating process line using a carry-in device (not shown). ALC board 1 carried in
1 is conveyed to the preheating process 101 of the next process.

The preheating step 101 is the ALC
This is a step for heating the plate 11 in advance, and the ALC plate 11 heated here is subjected to coating treatment in the first coating step 102 of the next step. Hereinafter, the coating process 102 will be described with reference to FIG.

In FIG. 2, reference numeral 10 denotes the entire coating apparatus according to the present invention, which is preheated in the preheating section 25 in the preheating step 101 and is conveyed by the AL.
Coating part 30 for applying the waterproof paint 12 to the surface of the C plate 11
Have.

The above-mentioned ALC plate 11 is preheated by the preheating unit 2 in advance.
At 5, for example, heated to 40-50 ° C. Next, the ALC plate 11 placed on the transport rollers 72 and 73 is sent in the direction of arrow a in the figure by the rotation of the transport rollers 72 and 73, whereby each processing by the coating unit 30 is performed.
Are sequentially applied to.

A control unit 22 is provided in the coating apparatus 10, and the control unit 22 controls each unit of the coating apparatus 10 according to the input command.

The ALC plate 11 heated to a predetermined temperature in the preheating section 25 as described above is sent to the coating section 30. A near the carry-in entrance of the ALC plate 11 of the coating unit 30
A sensor 26 for detecting the presence or absence of the LC plate 11 is provided. This sensor 26 transmits laser light to the ALC plate 1
Irradiate to the carry-in route of No. 1 and A based on the intensity of the reflected light
It is possible to use a device that detects the presence or absence of the LC plate 11.

The control section 22 constantly monitors the detection result of the sensor 26, and when detecting that the ALC plate 11 has been carried in, the control section 22 operates each part of the coating section 30 to cause the ALC board 11 to be carried in. It controls so that the coating unit 30 may perform the coating process on the plate 11.

The coating portion 30 of the coating portion 30 has a coating processing space inside thereof shielded from the external space. The coating processing space is divided into four processing spaces by partition walls 42, 43 and 44. Of these four processing spaces, the first processing space provided on the carry-in side of the ALC plate 11 is a pressure spray chamber for spraying the paint under pressure.
There is an injection coating section 32 for hitting the paint (coating composition) 12 on the surface of the ALC plate 11 at high pressure, and the paint 12 is supplied from the pump 52 to the injection nozzle 54 via the pipe 51.

At this time, the paint 12 has a coating hammering force of 2 g / cm ² or more (preferably 10 g / c) on the surface of the ALC plate 11 while its pressure is controlled by the liquid pressure gauge 53.
It is sprayed on the surface of the ALC plate 11 with a pressure such that m ² or more). As a result, the paint is almost pushed into the fine holes on the surface of the ALC plate 11.

The first part constituting the spray coating section 32
In the processing space of the
A shutter 41 is provided to prevent the water from leaking to the outside.

In the spray coating section 32, an ALC plate 1 having a lump of the coating material 12 sprayed on its surface by high-pressure spraying
1 is sent to the second processing space by the rotation of the transport rollers 72 and 73. The second processing space is an air blowing chamber for removing excess paint by air blowing, and by blowing air to the paint 12 in a state of being piled up on the surface of the ALC plate 11, An air blow part 33 is provided for scraping off excess paint from the surface. Air is supplied to the air cutter 65 provided in the air blow unit 33 from the blower unit 61 via the air distribution chamber 62, and the supplied air is supplied to the air cutter 65. It is supplied to the pair of air blow plates 65A and 65B, and high-pressure air is blown onto the paint on the ALC plate 11 from the tip portions thereof.

In this way, the ALC plate 11 is sent in the direction of the arrow a by the rotation of the conveying rollers 72, 73 while the air is blown by the air cutter 65, so that the excess paint among the paints deposited on the surface thereof. Paint is removed. In addition, the removed paint is the ALC plate 1
1 from both sides to the recovery tank 46. The paint 12 accumulated in the recovery tank 46 is sent to the pipe 75 by the pump 74 and is supplied to the filter (not shown) provided at the tip of the pipe 75.

Although not shown and described below, the filter is for removing impurities from the paint 12 carried out from the recovery tank 46, and is for filtering the recovered paint by passing it through the housing. There is a wire mesh. Impurities are removed from the recovered paint that has passed through the wire net and is stored in the tank. The filtered paint stored in the tank is returned to the coating device 10 by the pump again, and is spray-coated on the ALC plate 11 in the spray coating unit 32 in the same manner as in the case described above with reference to FIG.

Impurities such as ALC powder removed from the recovered paint through the filter are stored in a waste tank. Thus, in the coating apparatus 10, the air cutter 65
After the excess paint that has been scraped off by the method is recovered in the recovery tank 46, it is reused through the filter, so that the use efficiency of the paint is increased.

Subsequently, the ALC plate 11 from which the excess paint has been removed in the air blow section 33 of the coating apparatus 10 shown in FIG. 2 is sent into the third processing space by the rotation of the transport rollers 72 and 73. This third processing space is ALC
It is a processing space for depressurizing the surface of the coating liquid film applied on the surface of the plate 11, and the coating 12 is applied on the surface of the ALC plate 11.
This is a decompression chamber 34 for expanding and bursting the air reservoir in the state where there is air trapped in the remaining bubbles due to the formation of bubbles that are not completely filled in, that is, the coating liquid film. The air is drawn out by the blower unit 61, so that the inside of the decompression chamber 34 is kept at a pressure lower than the atmospheric pressure by 1.5 KPa or more, so that the air in the air reservoir in the bubbles is expanded. At this time, if there is little removal of the excess paint in the air blow section, the paint liquid film on the bubble inlet becomes thicker and cannot be repelled by the expansion of the air in the bubbles, and unpainted residue will occur.

In the decompression chamber 34, the ALC plate 11 in which the air reservoir in the air bubbles in the coating part has been repelled is the transfer roller 72,
It is sent to the fourth processing space that follows by the rotation of 73. The fourth processing space is a pressurizing chamber for blowing air onto the coating liquid film applied to the surface of the ALC 11, and the air reservoir inside the bubbles bursts to pressurize the coating inside the bubbles with the open inlet. A pressurizing chamber 35 is provided for pouring by the air flow.

Pressurized air is supplied to the pressurizing chamber 35 from the blower section 61 through the air distributing chamber 62. An air flow as shown by an arrow b in the figure is generated from the pressurizing chamber 35 to the adjacent depressurizing chamber 34, and the ALC plate 11 has a flow in the air flow.
Is sent, the painted portion of the surface is smoothly spread and the paint 12 flows into the inside of the bubbles.

Thus, the coating liquid film 20 is formed on the surface of the ALC plate 11 so that the inside of the bubbles is coated and there is no unpainted portion.

Here, FIG. 3 is a flow chart showing the coating processing procedure of the coating apparatus 10 described above in FIG.

As shown in FIG. 3, when the coating apparatus 10 enters the processing procedure from step A1, the ALC plate 11 to be coated moves to step A2.

In step A2, the coating device 10
After heating the ALC plate 11 by the preheating unit 25,
Move to step A3.

From step A3, the coating process in the coating section 30 is started, and in step A3, the coating device 10 is started.
Is a high-pressure jet of a lump of paint on the surface of the ALC plate 11 by the jet coating unit 32.

Then, the process proceeds to step A4, and in the air blow section 33, the excess paint is scraped off by the air cutter 65 to form the paint liquid film 20.

Further, moving to step A5, the decompression chamber 34 encloses air in the bubbles in which the paint on the surface of the ALC plate 11 is not completely filled, that is, the bubbles remaining by the formation of the paint liquid film 20. Of the air bubbles in the air bubbles are expanded to repel them, and the process proceeds to step A6.

In step A6, the coating apparatus 10 sends the ALC plate 11 in which air holes are popped in the bubbles to form the pinholes to the pressurizing chamber 35, so that the coating material formed on the surface of the ALC plate 11 is coated. Air is blown onto the liquid film 20 to pour the paint on the surface of the paint liquid film 20 into the air bubbles to close the pinholes and to smoothly extend the paint liquid film 20.

Next, FIGS. 4 (a), (b), (c),
With reference to (d) and FIG. 5, the state in which the coating liquid film is formed in the bubbles provided on the surface of the ALC plate 11 will be described in order of each step. That is, on the surface of the ALC plate 11, a large amount of the paint 12 is thickly attached by high-pressure spraying in the pressure spraying chamber of FIG.
3). At this time, the coating material 12 is pushed into the bubbles 3 existing on the surface of the ALC plate 11 from the inlet, and traps air in the depths of the bubbles 3 to form the air reservoir 5. In the air-blowing chamber of FIG. 2B, high-pressure air is jetted from the nozzle to remove the excess of the paint 12 attached to the surface of the ALC plate 11, and the coating liquid on the surface of the ALC plate 11 is removed. The film 20 is formed (step A4).

Then, in the decompression chamber of FIG.
Since the surface of the coating liquid film 20 applied to the LC plate 11 is depressurized, the air in the air reservoir 5 trapped in the bubbles 3 expands and is pushed into the inlet of the bubbles 3 as described above. The paint liquid film 20 made of the existing paint bursts and is discharged to the outside. A pinhole 4 is formed at a predetermined portion of the coating liquid film 20 from which the air is released (step A above).
5).

Further, in the pressurizing chamber of FIG. 4 (d), high-pressure air is blown from the nozzle onto the coating liquid film 20 on the surface of the ALC plate 11, whereby the air trapped in the bubbles 3 is removed. Around the pinhole 4 after being discharged, a part of the paint of the paint liquid film 20 flows into the pinhole 4 to close the pinhole 4, and the paint liquid film 20 is formed in this part. At the same time, the surface of the coating liquid film 20 can be smoothly extended by the air blowing (step A6).

Therefore, by carrying out the coating method of the present invention, as shown in FIGS. 4 (d) and 5, the coating liquid film 20 is formed so that there are no uncoated portions on the entire inner surface of the bubble 3. Can be formed.

The paint used for carrying out the above-described coating method of the present invention will be described below.

That is, the waterproof coating which is the undercoat coating composition used in this embodiment has a resin / pigment ratio of 1/10 to 6 /
10 (solid content weight ratio), the nonvolatile content at the time of coating is 50% or more, and the viscosity of # 4 Ford cup is 10 to 10.
An undercoat coating composition having a lamella length of 3 mm or less at 50 seconds / 25. For this purpose, the resin is dispersed in the resin (A), the pigment (B) and the solvent (C), and the acrylic emulsion resin is preferable as the resin.

Examples of the resin for forming the resin coating liquid film include water-soluble and water-dispersed (emulsion) type water-based resins such as acrylic resin and silicon-modified acrylic resin.
In particular, an emulsion resin of acrylic resin or silicon modified acrylic resin is preferably used. Hydrazide,
It can also be used as a mixture with a cross-linking agent such as glycidyl methacrylate, silanol, oxazoline, and metal oxide. Further, these resins are not limited to one type, and two or more types can be used in combination.

The undercoat coating composition of the present embodiment preferably has a lamella length of 3 mm or less. The lamella length refers to the degree of liquid breakage in a liquid film such as paint. The smaller the measured value, the easier the liquid film of paint breaks, and the easier it is to remove excess paint by blowing air. Lamella length is 3mm
If it exceeds, the liquid film of the paint is not well drained, and removal of the excess paint by air blowing tends to be difficult. More preferably, it is 0.1 to 2 mm.

By the way, the coating amount and the water permeation amount were compared with each other using an acrylic emulsion type sealer (Audite 155, manufactured by Nippon Paint Co., Ltd.) as the waterproof coating composition.

When a pressure spray shower and an air knife were used according to the method of the present invention (twice treatment), the sealer coating amount was 750 to 850 g / m ² and the water permeation amount was ² cc /.
It was 24 hours or less. On the other hand, in the conventional method of double-spraying a general spray, the coating amount of the sealer is 2100 g.
The water permeability was about 4 cc / 24 hours or less, even if it was / m ² . As a method of measuring the amount of water permeation, a method was used in which the funnel was turned upside down and stood on the surface of the ALC plate, and the circumference of the funnel was stopped with a sealer and water was injected.

The operation of the coating method of the present invention will be described below. That is, in the coating apparatus 10 for carrying out the present invention having the above-described functions and configurations, the excess coating material among the coating materials struck with a high pressure on the surface of the ALC plate 11 by the coating unit 30 is removed by the air cutter 6.
Shave off with 5. At this time, the coating liquid film 20 having a necessary and sufficient thickness is ensured on the surface of the ALC plate 11 in order to exhibit characteristics such as waterproofness that the coating material (coating composition) originally has. This is much more than in the conventional case in which an extra thickness is secured in response to the fact that air bubbles under the coating liquid film are broken and the film thickness becomes thin after coating drying, or uncoating occurs. It has a thin film thickness.

The coating liquid film having such a thickness is
Underneath that, there are bubbles in which the paint is not completely contained in the bubbles on the surface of the porous plate. The coating device 10 forms a paint liquid film in which the bubbles are generated. By putting the ALC plate 11 in the decompression chamber 34, air bubbles 3
The atmospheric pressure inside the chamber becomes higher than the atmospheric pressure in the decompression chamber 34, and the air in the air reservoir 5 trapped in the bubbles 3 expands and pops.

In this way, the paint liquid film 2 popped by the air reservoir 5
The surface of No. 0 has irregularities such as pinholes 4 in the popped portion, but the coating liquid film is not yet cured, and in such a state, it enters the pressurizing chamber 35 that follows. As a result, the surface of the coating liquid film 20 is leveled by the flow of the pressurized air by blowing air, and the coating material flows into the bubbles to form the coating liquid film 20 without any coating residue.

Thus, the surface of the ALC plate 11 does not have the unpainted air bubbles 3 which are sufficiently spread over the irregularities (fine holes), and a coating liquid film having a necessary and sufficient thickness is formed.

In the above-described embodiment, the ALC plate 11 on which the coating liquid film 20 is formed is put into the pressurizing chamber 35 in a state where the air reservoir 5 of the air bubbles 3 is burst by the depressurizing chamber 34, and the pressure is applied. Although the coating liquid film 20 is extended by the air flowing from the chamber 35 to the decompression chamber 34, the present invention is not limited to this, and the air may be blown onto the surface of the coating liquid film 20 using, for example, an injection nozzle. , The point is the paint liquid film 2
The surface of 0 may be exposed to the flow of air.

Further, in the above-described embodiment, the flow of air is generated from the pressurizing chamber 35 to the depressurizing chamber 34 so that the surface of the coating liquid film 20 is uniformly extended, but the present invention is not limited to this. Without the pressurizing chamber 35, the depressurizing chamber 3
The surface of the paint may be extended by causing the air to flow into the outer space from the outside space.

Then, as shown in FIG. 1, the ALC plate 11 on which the first coating step 102 has been completed is reversed in the setting step 103 in the conveying direction of the ALC plate 11, and then the second coating step 104 is performed. Be transported to. Here, the ALC plate 11 is coated by the coating device 10 based on the procedure described above. At this time, the second
In the coating process in the coating process 104, the coating device 1
Since the setting step 103 sets the direction of the ALC plate 11 to be carried into 0 in the opposite direction to the coating process in the first coating process 102, the ALC plate 11 is coated with the paint twice. In this case, the film thickness can be made more uniform.

Subsequently, as shown in FIG. 3, in step A7, the ALC plate 11 conveyed by the conveyor is
The process moves to the removal step 105 for removing the paint that has wrapped around the back surface (see FIG. 1).

This step is a feature of the present invention. In the above-mentioned painting step, the ALC plate 11 is coated with the coating material, and the coating material is blown by air to scrape off the excess coating material. Since the paint liquid film 20 is formed on the surface of the ALC plate 11, the paint naturally wraps around the back surface of the ALC plate 11.

In such a state, if the ALC plates 11 are stacked and stored in a state where they are directly stacked on the storage unit through the drying / cooling process described later, the weight and ambient temperature of the ALC plate 11 itself and the time when the ALC plates 11 are left as they are, etc. Due to the influence, the upper and lower ALC plates 11
This is to prevent the occurrence of a so-called blocking phenomenon in which the two stick together.

First, in this step 105, the ALC
The back surface of the plate 11 is cleaned using the cleaning device 110.

As shown in FIG. 6, a nylon washing brush 112 installed at a conveying level position of the ALC plate 11 by a conveyor 111 composed of an endless chain belt is used as a water tank 114 for storing water supplied from a water supply nozzle 113. By rotating the motor 115 inside, the back surface of the ALC plate 11 is washed with water and the paint on the back surface is scraped off by the brush 112.

Then, the paint removed together with the water in the water tank 114 is discharged to the drain tank 117 through the hose 116.

Thereafter, there is a step of further scraping the coating material sneaking around the back surface of the ALC plate 11 by using the subsequent contact portion 118 arranged at the transport level position.

Then, the contact portion 118 causes the AL
As shown in FIG. 7, the step of scraping off the coating material wrapping around the back surface of the C plate 11 is made of an L-shaped plate made of a plate spring-like steel plate material arranged at the transport level position of the ALC plate 11 by the conveyor 111. The contact portion 118 of (1) comes into contact with the back surface of the ALC plate 11 that is being transported, and scrapes off the paint that has flowed around the back surface of the ALC plate 11. As described above, in this embodiment, the contact portion 118 is directly brought into contact with the back surface of the ALC plate 11, and the coating material that wraps around the back surface is scraped off. Even if there is paint that cannot be removed, the paint that wraps around the back surface is scraped off by the contact portion 118, so that the paint on the back surface can be removed more reliably.

Further, the ALC plate 11 by the conveyor 111
Along with the conveyance of
By adopting the configuration in which the contact portion 118 is arranged at the transport level position by the conveyor 111 so as to contact the back surface of the LC plate 11, the paint scraping operation can be realized with a relatively simple structure.

Here, in the present embodiment, as shown in FIG. 7, a pair of the cleaning brush 112 and the contact portion 118 are arranged so as to be in contact with both ends of the ALC plate 11 conveyed by the conveyor 111. Then, the paint 12 sneaking around the back surfaces of the both end portions is brush-cleaned, and then scraped off by the contact portion 118. This is the coating device 1 described above.
ALC plate 1 in the coating process 102, 104 by 0.
1 is conveyed in the longitudinal direction thereof, in particular, since the backing of the paint occurs at the front and rear positions of the ALC plate 11 with respect to the carrying direction, it is necessary to remove the paint on the back surface of the both ends. Because there is. In the removing step 105, the ALC plate 11 is configured to be conveyed in the longitudinal direction similarly to the coating device 10, and the entire back surface of the ALC plate 11 is cleaned by using the single washing brush 112 and the single contact portion 118. It may be processed.

This step is a feature of the present invention. First, the paint that has flowed around the back surface of the ALC plate 11 is washed with the brush 1.
By washing with 12, the paint is scraped off. Further, the contact portion 118 is used to reliably remove the paint that could not be removed by the brush cleaning alone. It should be noted that the main removing step 105 does not necessarily have to have a step of cleaning with the water washing brush 112 and a step of scraping with the abutting portion 118, and depending on the state of adhesion of the paint, only one of them is the processing. However, there are cases where it can be handled. However, as described above, by including the cleaning process using the water washing brush 112 and the scraping process using the contact portion 118, the AL
It is possible to more reliably remove the paint that has flowed around the back surface of the C plate 11.

In step A8, the coating liquid film on the surface of the ALC plate 11 was dried (drying step 106 shown in FIG. 1).
After that, the ALC plate 11 is cooled (cooling step 107 shown in FIG. 1). After the paint is brush-washed with a water-washing brush 112 and further scraped off by the contact portion 118,
The ALC plate 11 is dried and cooled.

Subsequently, step A9 is a powder spraying step 108 for spraying a very fine powdery concrete powder made of the material forming the ALC plate 11 onto the ALC plate 11, and as shown in FIG. The powder 121 is evenly scattered on the surface of the stored ALC plate 11 by using the powder spraying machine 120. The next ALC plate 11 is stacked on top of it and the ALC
The powder 121 is also scattered on the surface of the plate 11.

By interposing the powder 121 between the upper and lower ALC plates 11 in this way, the front surface of the lower ALC plate 11 and the back surface of the upper ALC plate 11 are stuck together. The occurrence is suppressed more reliably.
In addition, without using the powder spreader 120, manually
The powder 121 may be spread on the surface of the ALC plate 11.

Since the powder 121 is a very fine powder, when the ALC plate 11 is used, the powder 1
21 is easy to use because it can be easily dropped by hitting the ALC plate 11 or washing it with water.

Thus, in step A10, AL
The coating process for the C plate 11 is completed, and the ALC plate 11 is carried out to the finished product storage space through a carrying-out process 109 by a carrying-out device (not shown).

[0094]

According to the present invention, the method has a step of removing the paint sneaking around on the back surface of the porous plate while cleaning with a brush, so that the porous plates after coating are stacked and stored in the storage portion. When going, it is possible to prevent the occurrence of the problem that the upper and lower porous plates are stuck to each other due to the paint wrapping around on the back surface.

Further, by having a step of scraping the coating material wrapping around on the back surface of the porous plate at the contact portion, when the porous plates after coating are stacked and stored in the storage portion, It is possible to prevent the problem that the upper and lower porous plates stick to each other due to the paint that has wrapped around.

Furthermore, by having a step of brush-cleaning the coating material that has flowed around the back surface of the porous plate and then scraping the back surface of the porous plate at the abutting portion, paint that cannot be completely removed by brush cleaning only Even if there is, the paint can be removed more reliably.

In addition, after the step of removing the coating material that has flowed around the back surface of the porous plate, the step of drying the porous plate and the powder of the material forming the porous plate are made into the porous material. By having a step of spraying on the surface of the plate, when the porous plates after coating are stacked and stored in the storage part, the powder is present between the upper and lower porous plates. Further, it is possible to further reduce the risk that a defect such as the upper and lower porous plates sticking to each other will occur.

[Brief description of drawings]

FIG. 1 is a diagram showing each step of a coating method of the present invention.

FIG. 2 is a schematic explanatory view of a coating apparatus for carrying out the coating method of the present invention.

FIG. 3 is a flowchart showing a coating method of the present invention.

FIG. 4 is a cross-sectional explanatory view showing a process of forming a coating liquid film in the bubbles on the surface of the ALC plate by the coating method of the present invention.

FIG. 5 is an enlarged cross-sectional explanatory view showing a main part of the ALC plate according to the coating method of the present invention.

FIG. 6 is a perspective view showing a cleaning device used in a removing step according to the coating method of the present invention.

FIG. 7 is a perspective view showing a contact portion used in a removing step according to the coating method of the present invention.

FIG. 8 is a perspective view showing a powder spraying machine used in a powder spraying step according to the coating method of the present invention.

FIG. 9 is an enlarged cross-sectional explanatory view showing an ALC plate coated by a conventional coating method.

FIG. 10: ALC coated by a conventional coating method
It is a board and is an expanded cross-sectional explanatory view showing a state in which a large amount of paint is applied to the surface.

[Explanation of symbols]

10 coating equipment 11 ALC plate (porous plate) 12 Waterproof paint 20 Paint liquid film 30 Painting Department 110 cleaning device 111 conveyor 112 Washing brush 113 Water supply nozzle 114 aquarium 115 motor 116 hose 117 drainage tank 118 Contact part 120 powder spreader 121 powder

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Chozo straight road             492-1, Urawari Higashi, Katada, Tsukuba, Ibaraki               Toa Industry Co., Ltd. (72) Inventor Toshiki Hamabe             Asahi 1-2 1-2 Yurakucho, Chiyoda-ku, Tokyo             Kasei Co., Ltd. (72) Inventor Takashi Naito             1-1, Castle Town East, Minami-ku, Nagoya City, Aichi Prefecture             Marine Products Co., Ltd. F-term (reference) 4D075 AA51 AA84 AC19 BB20Z                       BB24Z BB92Z DA06 DB12                       DC01 EA13 EB22 EB42

Claims (8)

[Claims] 1. A method for coating a porous plate, comprising the step of applying a coating to the surface of the porous plate during the transportation of the porous plate from the loading process to the unloading process. A step of spraying under pressure, a step of removing excess paint on the surface of the porous plate by air spraying, and a step of removing the paint sneaking around the back surface of the porous plate while cleaning with a brush. A method for coating a porous plate, characterized by: 2. The step of drying the porous plate after the step of brush-cleaning and removing the paint that has flowed around the back surface of the porous plate, and the material forming the porous plate is powdered. The method of coating a porous plate according to claim 1, further comprising: applying a powder to the surface of the porous plate. 3. A coating method for a porous plate, comprising the step of applying a coating to the surface of the porous plate during the transportation of the porous plate from the loading process to the unloading process, wherein a coating material is applied to the surface of the porous plate. A step of spraying under pressure, a step of removing excess paint on the surface of the porous plate by air spraying, and the coating material using an abutting portion that comes into contact with the coating that wraps around the back surface of the porous plate. A method for coating a porous plate, comprising a scraping step. 4. The step of scraping off the coating material sneaking around the back surface of the porous plate by the abutting portion includes a leaf spring-shaped abutting portion arranged at a transport level position of the porous plate. The coating treatment method for a porous plate according to claim 3, wherein the coating material is scraped off by being brought into contact with the back surface of the plate. 5. The step of drying the porous plate after the step of scraping off the coating material that has flowed around the back surface of the porous plate using the contact portion, and the material forming the porous plate is in the form of powder. 4. The method for coating a porous plate according to claim 3, further comprising the step of spraying the formed powder onto the surface of the porous plate. 6. A method for coating a porous plate, comprising the step of applying a coating to the surface of the porous plate in the course of transporting the porous plate from the loading process to the unloading process, wherein a coating material is applied to the surface of the porous plate. A step of spraying under pressure; a step of removing excess paint on the surface of the porous plate by air spraying; a step of removing the paint that has flowed around the back surface of the porous plate while cleaning with a brush; And a step of scraping off the coating material by using an abutting portion that comes into contact with the coating material that has wrapped around the back surface of the material sheet. 7. The step of scraping off the coating material sneaking around the back surface of the porous plate by the contact portion is performed by using a leaf spring-shaped contact portion arranged at a transport level position of the porous plate. The coating method for a porous plate according to claim 6, wherein the coating material is scraped off by bringing it into contact with the back surface of the plate. 8. A step of drying the porous plate after the step of brush-cleaning the coating material that has flowed around the back surface of the porous plate and further scraping it using the contact portion, and forming the porous plate. 7. A method of coating a porous plate according to claim 6, further comprising: applying a powder of the material to be powdered onto the surface of the porous plate.