JPH1028923A - Coating method for building board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to efficiently, safely and accurately plot design patterns on the surface of a building board previously formed with a lower layer colored coating film on its surface by separating an electromagnetic vibration part and an ink discharge control part and directly coupling a needle valve and this electromagnetic vibration part by a flexible connecting material. SOLUTION: An ink jet printer is separately provided with an ink chamber 3 and a electromagnetic vibrator 4. The needle valve 2 and the core 6 of the electromagnetic vibrator 4 are connected by the flexible connecting material 7. The needle valve 2 is opened and closed by the operation of the electromagnetic vibrator 4. The electromagnetic vibrator 4 is provided with a spring 8. This spring 8 is compressed with the core 6 by electromagnetic force in the state that, for example, the electromagnetic vibrator 4 is electrically on, by which the connecting material 7 and the needle valve 2 are pushed out to close a nozzle hole 1. On the other hand, the spring 8 pushes up the core 6 by its restitutive force in the state that the vibrator is electrically off. The connecting material 7 and the needle valve 2 are pulled up by the movement of the core 6 to open the nozzle hole 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method of painting and finishing a building board, and more particularly, to a building board having a lower colored coating film formed on a surface thereof, while conveying the building board with a conveyer. The present invention relates to a novel painting method for painting an excellent pattern.

[0002]

2. Description of the Related Art In recent years, for exterior walls of houses, bricks, tiles or natural stones having the appearance of being piled up side by side are preferred, and the tendency to spread is increasing. However, in the production of building boards having such an appearance, the surface of the unhardened hydraulic plate material is pressed by a press through a template having an uneven pattern formed of bricks, tiles, A surface makeup process of forming a concavo-convex pattern expressing a natural stone surface or the like on the surface of the plate material, then passing through a curing curing process, and then applying a paint using a known spray coating machine, flow coater coating machine, roll coater coating machine, or the like. After that, it is a building board. However, the building board obtained by such a method has either a single-color surface finish or a two-color finish using a height difference, and each of them is a real brick or tile, or It is completely different from the appearance of building materials made of natural stone and has poor design.

[0003] From such a viewpoint, there has been a long-awaited need for the development of a technology capable of painting and finishing a portion in a different color such as brick, tile or natural stone. As a solution to this problem, Japanese Utility Model Laid-Open No. 63-149725 discloses an electronic control method in which an ink jet nozzle is moved to the left and right and a print target plate is moved back and forth, or the jet nozzle is fixed while the print target plate is fixed. It has been proposed to perform a printing operation while moving the print head in the front-rear direction together with the sliding shaft.

[0004] However, in the former method, in order to print over the entire width by moving the long printing target plate back and forth while moving the ejection nozzle to the left and right, it is necessary to obtain the stopping accuracy in the transport device. However, there is a disadvantage that the advanced technology is required and the printing time is considerably long. On the other hand, in the latter method, in order to fix a long printing target plate and perform printing while moving the ejection nozzle to the left, right, back and forth by moving the sliding shaft, the moving mechanism of the sliding shaft has to be robust. High precision is required, and therefore, efficient printing on a long building board is inappropriate in terms of printing speed and maintaining accuracy.

In the method described in JP-A-6-155729, a large number of ink discharge nozzles are linearly fixed and arranged on a conveyor for transporting a building board. It is enough in terms of maintenance.
However, since the electromagnetic oscillation system and the ink chamber are integrated into an electromagnetic valve system for controlling ink ejection, and the valve unit and the nozzle unit are connected with a vinyl pipe,
The following disadvantages occur.

[0006] Since the electric circuit and the ink path are completely integrated, when a solvent-based ink is used, there is a great risk that a fire may occur due to electric spark due to failure of the electric system or the like. When a failure occurs in the solenoid valve, it is necessary to replace the solenoid valve irrespective of whether it is an electrical factor or an ink factor, and it is difficult to determine the cause. In any type of jet printer, the deposition or clogging of the colorant in the ink path, ink chamber, and nozzles is the biggest issue. This problem is a major issue.

[0007] Since each ink feed pipe from the solenoid valve to the nozzle hole is made of a vinyl pipe, a pressure loss occurs due to the elasticity of the vinyl pipe. And the size of the ejected ink droplets differs. As described above, although the length of the ink feed pipe must be the same, the solenoid valve has a diameter of 8 to 12 mm while the nozzle hole diameter is as small as 50 to 300 μm and the nozzle pitch is as small as 100 to 400 μm. And their arrangement positions are very limited.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and provides a method for producing a patterned pattern on the surface of a building board having a lower colored coating film formed on the surface in advance. It is an object of the present invention to provide a coating method that can efficiently, safely and accurately draw using an inkjet printer that is easy to use and that can obtain a building board having excellent durability.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies in order to achieve the above object, and as a result, the present invention has been changed to a structure in which the electromagnetic vibration portion and the ink discharge control portion are conventionally integrated. Is a needle valve system that separates them and opens and closes them at the nozzle hole. The needle valve and the electromagnetic vibration part are directly connected by a flexible connecting material (for example, a wire) and the needle is operated by the operation of the electromagnetic vibrator. It has been found that the above disadvantages can be improved by opening and closing the valve, and the present invention has been completed.

That is, the coating method of the present invention is a method of painting a pattern on a surface of a building board having a lower colored coating film formed on the surface thereof in advance while conveying the building board by a conveyor. A needle valve for opening and closing the nozzle hole, an ink chamber and an electromagnetic vibrator flowing through the nozzle hole, and the ink chamber and the electromagnetic vibrator are separately provided; A needle valve electromagnetic opening / closing type ink jet printer which is connected to a core of the electromagnetic vibrator by a flexible connecting material so that the needle valve opens and closes by the operation of the electromagnetic vibrator. Nozzle holes are arranged in the width direction of the conveyor at a position above the building board, while a control signal from a computer in which pattern pattern data corresponding to a pattern to be painted is stored in advance. By controlling the vibration of each of the electromagnetic oscillators to control the opening and closing of each of the needle valves, and controlling the discharge of the ink sent at a low pressure from each of the nozzle holes, the surface of the building board is controlled. It is characterized in that a pattern is painted.

Hereinafter, the coating method of the present invention will be described in detail. FIG. 1 (a schematic sectional view showing a part of the printer) and FIG. 2 show a main part of a needle valve electromagnetic opening / closing type ink jet printer used in the coating method of the present invention.
(A schematic sectional view taken along the line AA in FIG. 1). As is clear from FIGS. 1 and 2, the ink jet printer used in the present invention has a large number of ink discharge nozzle holes 1, a needle valve 2 for opening and closing the nozzle holes, an ink chamber 3 flowing through the nozzle holes, and an electromagnetic vibrator. 4 and the electromagnetic vibrator 4
Has a coil 5 and a core 6 as is known. The ink chamber 3 and the electromagnetic vibrator 4 are provided separately, and the needle valve 2 and the core 6 of the electromagnetic vibrator 4 are connected by a flexible connecting member 7. By using a wire such as a piano wire or a stainless steel wire as the connecting member, the needle valve and the connecting member can be constituted by one wire. This wire is provided with, for example, a slidable sheath or a suitable guide so that the needle valve 2 can be opened and closed by the operation of the electromagnetic vibrator 4.

The electromagnetic vibrator 4 is provided with a spring 8. For example, when the electromagnetic vibrator 4 is in an electrical ON state, the core 6 compresses the spring 8 by an electromagnetic force and pushes out the connecting member 7 and the needle valve 2. To close the nozzle hole 1 while
In a state where the electricity is off, the spring 8 pushes up the core 6 by the restoring force, and the movement of the core 6 raises the connecting member 7 and the needle valve 2 to open the nozzle hole 1. Alternatively, conversely, when the electromagnetic vibrator 4 is in the electric-on state, the core 6 stretches the spring 8 by the electromagnetic force, pulls up the connecting member 7 and the needle valve 2 to open the nozzle hole 1, and in the electric-off state, The spring 8 pulls down the core 6 by its restoring force, and the movement of the core 6 pushes out the connecting member 7 and the needle valve 2 to close the nozzle hole 1. In FIG. 1, a set of needle valves, for simplification of the drawing,
Only the ink chamber and the electromagnetic vibrator are shown.

Each nozzle hole 1 of the ink jet printer used in the present invention preferably has an inner diameter of 100 to 500.
μm holes. The nozzle holes may be arranged linearly in a row in the width direction of the conveyor, or 16 or 32 nozzle holes may be arranged.
One or 64 nozzle holes may be defined as one block, and the blocks may be arranged in a staircase shape, an uneven shape, a mountain shape, or a combination thereof. Regarding the arrangement of the nozzle holes, it is more preferable to arrange a certain number of blocks and to combine and arrange the blocks from the viewpoint of maintenance such as detection of defective nozzle holes, than to arrange them in a completely linear manner. The nozzle holes are arranged so that the distance between the nozzle holes is preferably a pitch of 0.5 to 3 mm, but the nozzle hole diameter and the pitch between the nozzle holes can be appropriately selected depending on the desired image quality accuracy. . Under these conditions, approximately 10-5
A pattern with an image quality accuracy of 0 dpi can be drawn.

As described above, in the ink jet printer used in the present invention, preferably, the nozzle holes are arranged so that the distance between the nozzle holes has a pitch of 0.5 to 3 mm. If the electromagnetic vibrators are to be arranged in a straight line, the outer diameter of each electromagnetic vibrator must be 0.5 to
It must be about 3 mm or less, and it is extremely difficult to manufacture an electromagnetic vibrator having such an outer diameter. Therefore, it is practical to displace the arrangement position of the electromagnetic vibrators not only in the width direction of the conveyor but also in the traveling direction so that each electromagnetic vibrator contacts or separates. For example, as shown in FIG. 2, four electromagnetic vibrators 4A, 4B, 4C, and 4D that are respectively connected by flexible connecting members to opening and closing needle valves of four continuous nozzle holes are arranged in this order. Then, the electromagnetic vibrators are displaced not only in the width direction of the conveyor but also in the traveling direction so as to contact or separate from each other, and these 4A, 4B, 4C and 4D are repeated to constitute an ink jet printer. Note that the number of electromagnetic vibrators constituting the repeating unit can be arbitrarily determined according to the desired distance between the nozzle holes and the size of the outer diameter of the electromagnetic vibrator.

The nozzle hole 1 may be constituted by a hole formed in the plate 14 as shown in FIG.
A tubular projection 16 provided on a plate 15 as shown in FIG.
May be configured. These plates 14 or 1
5 can be directly attached to the ink jet printer or, as shown in FIGS.
The nozzle plate may be attached to a support plate 17 having a smaller opening so as not to block the nozzle hole, and the support plate 17 may be attached to the inkjet printer.

In FIG. 1, reference numeral 9 denotes an ink supply port, and reference numeral 10 denotes a packing for keeping the ink chamber liquid-tight. In the ink jet printer used in the present invention, if necessary, an outside air intake port 11, an exhaust port 12, and a separating wall 13 are provided, and air is sucked from the exhaust port and taken in from the outside air intake port 11 into the ink jet printer. By passing the gas through the opening in the separating wall 13 and discharging the gas through the exhaust port 12, it is possible to prevent the flammable volatile vapor from the ink from flowing into the electric system.

When an ink jet printer as described above is used, very weak static or pressurized ink enters the ink chamber 3 through the ink supply port 9. On the other hand, the electromagnetic vibrator is vibrated by the electromagnetic driving signal, and the needle valve 2 connected by the wire 7 is opened and closed by the vibration to control the ejection of the ink droplet from the nozzle hole 1. In the coating method of the present invention, a conveyor speed of 1 to 50 m / min can be generally used, but a speed in a range of 10 to 35 m / min in consideration of productivity and image quality. Preferably, there is.

The term "building board having a lower colored coating film formed on the surface in advance" used in the present invention means a slate board, a wood chip cement board, a pulp cement board, an asbestos whose base material is used for an outer wall material or an interior material. Cement board, lightweight aggregate-mixed cement board, foam concrete board, glass fiber reinforced cement board, calcium silicate board, magnesium carbonate board, or other hydraulic board material, even if the surface is flat or processed into irregularities It may be. Further, the lower colored coating film is a coating of any type of conventionally known various colored coatings such as an organic solvent type such as a baking type, a normal drying type, and an active energy ray curing type, an aqueous type, and a non-solvent type. And what you get
A coating film obtained by combining these with any type of conventionally known base material reinforcing primer such as a baking type, a normal drying type, an organic solvent type such as an active energy ray-curing type, an aqueous type, and a solventless type. It is.

The ink (or paint) used in the present invention is a material containing a resin, a coloring pigment, and a solvent as main components. The resin is not particularly limited as long as it has good adhesion to the lower colored coating film described above, and conventionally known ink (or paint) resins can be used. Specifically, acrylic resin, vinyl resin,
Various resins such as acrylic silicone resin, fluorine resin, silicon resin, and chlorinated resin are typical examples.

Examples of the above color pigments include titanium oxide, iron oxide, composite oxides (nickel titanium, chromium titanium, bismuth vanadium, etc.), carbon black,
Various inorganic pigments such as graphite, and various organic pigments such as quinacridone, diketopyrrolopyrrole, benzimidazolone, isoindolinone, anthrapyramidine, phthalocyanine, sulene, and dioxazine are listed as typical examples. Can be

Further, the above-mentioned solvent has a specific evaporation rate (value by a weight method with respect to 100 parts of normal butyl acetate) of 50.
380 to 380, preferably 80 to 200. Solvents having a specific evaporation rate in the above range include aromatic hydrocarbon solvents such as toluene and xylene; ethyl alcohol, isopropyl alcohol,
Representative solvents include alcohol solvents such as isobutyl alcohol; ester solvents such as normal propyl acetate, normal butyl acetate, sec-butyl acetate and isobutyl acetate; and aliphatic hydrocarbon solvents such as petroleum benzine and rubber volatile oil. Can be In the present invention, it is also possible to use a solvent having a specific evaporation rate outside the above range in an amount of 20% by weight or less based on the total solvent mainly composed of the above-mentioned specific solvent.

Ink (or paint) used in the present invention
Is composed mainly of the above-described resin, coloring pigment, and solvent, and further, if necessary, blended with an extender pigment, a dye, a conductivity adjuster, a surfactant, and the like.
In this case, the ratio of each component is appropriately 4 to 50% by weight of resin, 1 to 30% by weight of coloring pigment, and 49 to 95% by weight of solvent. Then, after mixing and stirring the above components, the ink is filtered and purified using a filter having a pore size of about 1/10 or less with respect to the diameter of the nozzle in the ink jet printer used in the method of the present invention. Is obtained.

The viscosity of the ink (or paint) used in the present invention is generally from 5 to 15 cps (20 ° C.), preferably from 6 to 12 cps (20 ° C.). If the viscosity of the ink (or the paint) is out of the above range, the ink (or the paint) discharged from the nozzle is difficult to become a normal dot-shaped ink droplet (or the paint droplet), which is not preferable. In addition, ink (or paint)
Other properties of the surface tension: 20 to 60 dynes / c
m, specific resistance: 200 to 3000 Ω · cm, specific gravity: 0.8
3 are preferable.

In the coating method of the present invention, a clear paint may be applied to the entire surface of the coating film on which the pattern is applied for the purpose of adjusting the appearance of the finished surface and ensuring durability. As such a clear paint, a clear paint conventionally used for an inorganic decorative board, for example, a transparent or translucent clear paint or a colored clear paint can be used. That is, baking type using a binder such as acrylic urethane resin type, acrylic epoxy resin type, acrylic melamine resin type, acrylic silicon resin type, acrylic fluororesin type, fluororesin type, silicon resin type, etc. Conventionally known clear coatings (colors) such as an organic solvent type such as a line curing type and an aqueous type can be used. In addition, these clear paints include matting agents, pigments, various beads, metal powder,
It is also possible to mix and use ceramic powder and the like in such an amount that the ink applied surface is not hidden. These paints can be applied using a known coater such as an air spray, an airless spray, a flow coater, and a roll coater. Regarding the timing of applying the clear paint, the ink surface of the pattern may be in an undried state or after being dried.

In the coating method of the present invention, a plurality of rows of nozzle holes arranged in the width direction of the conveyor are arranged before and after in the moving direction of the conveyor, and a different color ink is ejected from each nozzle hole row. Multi-color painting is also possible.

[0026]

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a partially cutaway schematic front view for explaining an example of the embodiment of the present invention, and is a schematic right side view of the embodiment shown in FIG.
FIG. 4 is a right side schematic side view for explaining another example of the embodiment of the present invention.

As shown in FIGS. 5 and 6, the building board 21 having a lower colored coating film formed on the surface thereof is a conveyor 22.
Is transported forward. Above the conveyor 22, an inkjet printer 23 of a needle valve electromagnetic opening / closing type including individual components as illustrated in FIGS. 1 and 2 is disposed.
Nozzle holes are arranged over the entire width direction of No. 2. A coating ink 25 in an ink tank 24 is pumped into an ink supply port of each component of the inkjet printer 23 by a pump 26. Although not shown, the ink supply system can be connected to the ink tank 24 via a relief valve so that even if bubbles are generated in the ink supply system, it can be easily removed. 2
Reference numeral 7 denotes an electromagnetic vibrator control device that controls the vibration of each electromagnetic vibrator of the ink jet printer to control the opening and closing of each needle valve, and controls the discharge of ink sent at low pressure from each nozzle hole. . Reference numeral 28 denotes pattern pattern data which records a pattern corresponding to a pattern to be painted, 29 denotes a computer which issues a control signal to the electromagnetic vibrator control device 27 based on the input pattern data 28, and 30 denotes a projector 31 And a photodetector 32 provided at predetermined positions on both sides of the building board transport path on the conveyor 22, and transmits a detection signal to the computer 29. Reference numeral 33 denotes an encoder connected to the driving roll 34 of the conveyor 22, which transmits a pulse to the computer 29 at each minimum rotation angle, for example, every 360/2000 minimum rotation angle.

In the coating method of the present invention, for example, when a building board 21 to be coated having an uneven pattern on its surface is advanced on a conveyor 22 after the undercoat sealer processing, a predetermined position of the front end of the building board 21 is determined. The sensor 30 detects the arrival and sends a detection signal to the computer 29. On the other hand, with the operation of the conveyor 22, pulses are transmitted to the computer 29 from the encoder 33 provided on the drive roll 34. The computer 29 starts counting the pulses based on the signal from the sensor 30. When the number of pulses reaches a set area stored in advance, the computer 29 sequentially generates a control signal based on the pattern data 28 of the pattern according to the number of pulses. A transmission command is sent to the slave controller 27, whereby the electromagnetic oscillator controller 27 individually controls the vibration of each of the electromagnetic oscillators to control the opening and closing of each needle valve. The discharge from each nozzle hole is controlled, and when the needle valve is opened, it is jetted from the nozzle hole to a required position on the surface of the building board 21 being conveyed to draw a pattern based on the pattern data 28. In this case, since the surface of the building board 21 and the nozzle holes are not in contact with each other, the drawing of the pattern can be performed without any problem regardless of the unevenness of the surface of the building board 21.

In the case of painting a multicolor pattern on a building board, as shown in FIG.
Are installed, and these inkjet printers 35, 3
The inks of different colors are supplied to the ink jet printers 6 and 37 in the same manner as in the above example. The surface of the building board 21 to be fed is coated with a multicolor pattern.

[0030]

As described above, according to the present invention, the electromagnetic vibration portion and the ink discharge control portion are separated from each other, and the needle valve system is opened and closed at the nozzle hole. Is connected directly with a flexible connecting member to open and close the needle valve by the operation of the electromagnetic vibrator. Therefore, there is no danger of fire occurring due to electric sparks due to failure of the electric system, and coloring of the nozzle. There is no sedimentation or clogging of the agent and no difference in the size of the ejected ink droplets. Using a printer enables efficient, safe and accurate drawing.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a main part of an inkjet printer of a needle valve electromagnetic opening / closing type used in a coating method of the present invention.

FIG. 2 is a schematic cross-sectional view taken along line AA of FIG.

FIG. 3 is a schematic perspective view showing an example of a plate having nozzle holes.

FIG. 4 is a schematic perspective view showing an example of a plate having a tubular projection nozzle hole.

FIG. 5 is a partially cutaway schematic front view for explaining an example of an embodiment of the present invention.

FIG. 6 is a schematic right side view of the embodiment shown in FIG. 6;

FIG. 7 is a right side schematic side view for explaining another example of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink discharge nozzle hole 2 Needle valve which opens and closes a nozzle hole 3 Ink chamber 4 Electromagnetic vibrator 5 Coil 6 Core 7 Flexible connection material 8 Spring 9 Ink supply port 10 Packing 11 Outside air intake 12 Exhaust port 13 Separation wall 14 Plate 15 Plate 16 Tubular protrusion 17 Support plate 21 Building plate 22 Conveyor 23 Inkjet printer 24 Ink tank 25 Painting ink 26 Pump 27 Electromagnetic vibrator controller 28 Pattern pattern data 29 Computer 30 Phototube sensor 31 Projector 32 Receiver 33 Encoder 34 Drive Roll 35, 36, 37 Inkjet Printer

Claims (4)

[Claims] 1. A method for painting a pattern on a surface of a building board having a lower colored coating film formed on the surface thereof, while conveying the building board by a conveyor, comprising a plurality of ink discharge nozzle holes, and needles for opening and closing the nozzle holes. A valve, an ink chamber flowing through the nozzle hole, and an electromagnetic vibrator, wherein the ink chamber and the electromagnetic vibrator are provided separately, and the needle valve and the electromagnetic vibrator core Is a needle valve electromagnetic opening / closing type ink jet printer which is connected by a flexible connecting material so that the needle valve opens and closes by the operation of the electromagnetic vibrator. Are arranged in the width direction of the conveyor at a position above, while the pattern signals corresponding to the pattern to be painted are stored in advance by a control signal from a computer which stores the pattern data corresponding to the pattern. Painting a pattern on the surface of the building board by controlling the movement of the needle valve to control the opening and closing of each needle valve and controlling the discharge of ink sent at a low pressure from each nozzle hole. A method for painting building boards, characterized by the following. 2. The method for coating a building board according to claim 1, wherein an ink jet printer of a needle valve electromagnetic opening / closing type in which the needle valve and the connecting member are formed of a single wire is used. 3. A multi-color coating by arranging a plurality of rows of nozzle holes arranged in the width direction of the conveyor before and after in the moving direction of the conveyor, and discharging a different color ink from each nozzle hole row. The method for coating a building board according to claim 1 or 2, wherein 4. The method for coating a building board according to claim 1, wherein a clear paint is further applied to the surface of the building board on which the pattern is painted.