JP2004089933A - Method of coating plate-like body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of coating a plate-like body by which the upper surface and if necessary, the butt end surfaces of the plate-like body are coated while preventing sticking of a coating material on an undesirable part and the plate-like body having excellent surface smoothness is obtained. <P>SOLUTION: The method of coating the upper surface P1 and the butt ends P2-P5 of the plate-like body P is performed by passing through the curtain 17 of a coating material by a head 13. The plate-like body P is placed on a fixture 16 provided with a supporting surface 16A having a size smaller than the plane size of the plate-like body and coated. The plate-like body P is transported so that the butt end surfaces P2-P5 passes through the curtain 17 at an angle of nearly 45° with respect to the curtain 17. After being coated one time jointly using the fixture 16 provided with an inclined surface 16A, the plate-like body P is dried and polished. After that, second time coating and drying are carried out to obtain the plate-like body having excellent surface smoothness. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of coating a plate-like body by a flow coater method, and more particularly, to a method of coating peripheral equipment of an object to be coated with a paint without contaminating the upper surface of the plate-like body and, if necessary, a cut surface. The present invention relates to an improvement in a coating method that can be adapted to simultaneously apply a coating and that can dramatically improve the smoothness of the upper surface.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, a flow coater method has been known as a method of coating a plate-shaped body or the like used for a building material as an object to be coated. The flow coater method is a coating method performed by flowing paint in a curtain shape from a slit of a head that is long in the lateral direction, and passing a workpiece under the curtain at a constant speed. There is no paint loss in that the paint that has flowed down besides the painted material can be circulated and used, and the conveyor speed is high, the paint can be applied at high speed, and the work environment is sanitary with no paint mist scattering. And so on.
[0003]
[Problems to be solved by the invention]
However, in the flow coater method, since the object to be coated is painted while being directly placed on the conveyor and moved, the paint adheres to the belt constituting the conveyor, and the paint adheres to the belt. There is an inconvenience that the paint adheres to the surface of the object to be coated, which must be done.
[0004]
By the way, in the flow coater method, in order to paint the upper surface of the plate-shaped body and the lip end, the lip end of the plate-shaped body is kept at a fixed angle with respect to the feeding direction, and the curtain is passed through in this state. There is known a method of simultaneously coating the upper surface of a plate-like body and the surrounding wood edge.
[0005]
However, in such a flow coater method, two successive coatings are performed by first coating the upper surface of the plate-like body and the two cleave surfaces on the curtain side, and then coating the upper surface and the other cleave surface before drying. And drying. Therefore, a volatile component in the coating material tends to cause diffusion and flow, which impairs the surface smoothness of the coated surface and makes it difficult to achieve a high gloss mirror finish. In addition, at the ridgeline between the upper surface of the plate-like body and the lip surface, a partial rise of the coating film occurs due to the surface tension of the paint, which is a factor that hinders the smoothness of the upper surface. Such partial swelling of the coating film appears, for example, in a curved shape when the portion is projected with a fluorescent lamp. Further, irregularities of the material of the plate-like body appear on the finished surface as they are, and this also becomes a factor that hinders the surface smoothness. In addition, in the flow coater method, the amount of paint applied to the top surface of the plate-like body is reduced to about 1/3, and the difference in the amount applied is further increased by performing only two coats on the upper surface. Therefore, there is also a problem that the coating film on the upper surface becomes relatively thick, causing cracks in the coating film, and a color tone difference due to a difference in coating film thickness depending on the color of the topcoat paint.
[0006]
[Object of the invention]
The present invention has been devised in view of such inconvenience, and its object is to effectively utilize coating efficiency by a flow coater method and to apply a coating material to an area not intended for a plate-like body. An object of the present invention is to provide a coating method capable of avoiding adhesion.
[0007]
It is another object of the present invention to provide a method for coating a plate-like body of high quality by improving the upper surface painting finish accuracy, that is, the surface smoothness of the plate-like body.
[0008]
Yet another object of the present invention is that when coating the upper surface of the plate-like body and the kiguchi surface, the coating of the kiguchi surface becomes relatively thin, that is, the coating of the upper surface and the kiguchi surface coating film An object of the present invention is to provide a method for coating a plate-like body capable of reducing a difference in film thickness.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a method of painting the upper surface of a plate-like body by passing a paint curtain,
The plate-shaped body is placed on a jig provided with a support surface smaller than the plane size of the plate-shaped body, and in this state, the jig and the plate-shaped body are passed through the curtain to perform coating on the upper surface, The method is adopted. With such a configuration, the paint does not adhere to the jig even when the plate passes through the paint curtain. Or the like can be reliably eliminated even if the paint is placed on the lower surface (back surface) of the plate-shaped body.
[0010]
Furthermore, the present invention relates to a method of coating the upper surface of a plate-like body and the surrounding edges by passing through a paint curtain,
The plate-shaped body is placed on a jig having a support surface smaller than the plane size of the plate-shaped body,
A method is also adopted in which the jig and the plate-like body are passed through the curtain in a state where the edge of the edge is disposed at an angle of approximately 45 degrees with respect to the curtain, so that the upper surface and the edge of the edge are painted. Can be.
[0011]
Further, the present invention is a method of painting the upper surface of the plate-like body and the surrounding edges of the wood by passing through a paint curtain,
The plate-shaped body is placed on a jig having a support surface smaller than the plane size of the plate-shaped body,
A first method for painting the upper surface and the curtain-side edge of the curtain by passing a jig and a plate-like body through the curtain in a state where the edge of the edge is arranged at an angle of approximately 45 degrees with respect to the curtain. Coating process,
A drying step of drying the painted surface,
A grinding step of grinding the painted surface,
A plate-shaped body which has been coated through a second coating step of coating the plate-shaped body through a curtain in a direction opposite to the first coating step and coating the upper surface of the plate-shaped body and the opening on the curtain side You can also get your body. According to such a method, the surface smoothness of the painted surface can be improved by drying the painted surface in the first painting process and employing the grinding process before the second painting process. Therefore, it is possible to eliminate the inconvenience that the uneven surface of the material appears, and it is possible to perform the high gloss mirror finish by performing the subsequent second coating process. In addition, it becomes possible to suppress that the coating film on the upper surface becomes relatively thicker than the coating film on the wood opening surface, and a crack in the coating film or a color difference due to a difference in the coating film thickness due to the color of the top coat paint occurs. Such inconvenience can be solved. Preferably, the support surface is an inclined surface, and the jig passes through the curtain in a direction in which a front portion along the moving direction is gradually higher than a rear portion. As a result, while it is possible to increase the amount of application on the wooden surface, it is possible to relatively reduce the amount of application on the upper surface, and it is possible to reduce the difference in the coating thickness described above.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, it is important to study the properties of the paint used. That is, when a high gloss mirror finish is used, the flow (leveling) and bubble removal of the paint applied to the plate-like body must be good. The choice of leveling agent is also relevant, but this is related to the paint viscosity. In addition, in the coating of the open end surface, since the open end surface is located in the vertical plane at the time of coating, it is also necessary to prevent the dripping of the paint and the occurrence of the unpainted portion. Related to this prevention is the amount of paint applied and the relative speed at which the lip edge hits the paint curtain, that is, the speed of the belt moving the plate. It is effective to impart thixotropic properties to the sagging of the paint. For example, by adding a thixotropic agent to a polyester resin, a UV-curable resin, or the like, the expected effect of suppressing sagging can be obtained.
Therefore, the mutual balance between the paint viscosity, the applied amount and the belt speed is important. In the present invention, the paint viscosity is about 15 to 50 seconds, preferably 25 to 40 seconds (Iwata Cup NK-2 measurement seconds). The coating amount of the coating material is about ^{50g / m 2 ~150g / m 2} , preferably in the range of ^{70g / m 2 ~100g / m 2} . The belt speed is 50 m / min to 100 m / min, preferably in the range of 60 m / min to 80 m / min.
The reason for setting the paint viscosity to 15 seconds to 50 seconds is that if the viscosity is less than 15 seconds, the paint tends to sag on the tip surface, while if it exceeds 50 seconds, the leveling property of the flat surface is poor and the entrapment of air bubbles increases. It is.
Further, the coating amount was ^50g / ^{m 2 ~150g} / m 2, in less than 50 g / ^{m 2,} while the entire surface of the butt end face is less likely to be fully coated, it exceeds 150 g / ^{m 2,} coating the butt end surface This is because dripping easily occurs.
Furthermore, the reason why the speed of the belt is set to 50 m / min to 100 m / min is that if the speed is less than 50 m / min, it is difficult to sufficiently coat the entire surface of the lip, but if it exceeds 100 m / min, the coating amount on the lip is reduced. Because it is too much.
[0013]
In the present invention, it is also important to design the hardness of the coating film so that it can be ground in consideration of workability and accuracy of the finished surface. Specifically, it is preferable that the pencil hardness is HB to 5H. By grinding the upper surface of the plate-like body after the first coating process, the unevenness of the plate-like body itself is removed and smoothed, and further, the coating on the upper surface is thinned by the grinding, and the thickness of the coating between the upper surface and the kiguchi is reduced. The difference can be reduced. As the grinding conditions, for example, it is preferable to remove irregularities on the upper surface of the plate-like body using a fine sandpaper of # 320 or less.
[0014]
The paint used in the present invention is a UV-curable paint (solvent-based, non-sol-based), urethane resin paint, polyester resin paint, or water-based paint, each of which is clear, colored with a dye, or added with pigment, pearl, metallic, etc. Opaque paints can also be selected. In the flow coater method, as long as the above-mentioned coating conditions are satisfied, the structure of the head may be a slit type or an overflow type.
[0015]
The jig of the present invention may have a support surface that is substantially horizontal, in addition to the support surface being inclined. When the jig is made of a material having a tilted support surface, the jig and the plate have such a friction that the relative slip between the jig and the plate can be regulated while the plate is placed on the support surface. It is preferable that the jig itself has resistance, is lightweight, has excellent workability, has good conductivity, and is hardly charged, and furthermore, the jig itself does not attract dust or the like. Specifically, for example, a low foaming conductive crosslinked polyethylene foam and the like can be exemplified.
[0016]
Further, as the plate-like body in the present invention, MDF, plywood, particle board, calcium silicate plate, flexible plate, steel plate and the like can be suitably used. Further, the plate-shaped body may have a substantially rectangular shape in plan view, or may be a plate-shaped body provided with a peripheral surface curved in plan view.
[0017]
The coating method according to the present invention can be performed using the coating apparatus shown in FIG. The coating apparatus 10 includes a first belt conveyor 11, a second belt conveyor 12 arranged in a horizontal line at a predetermined distance from the belt conveyor 11, and an upper part between the belt conveyors 11, 12. , A paint receiver 14 disposed below the head 13, and a pump 15 for returning the paint flowing down to the paint receiver 14 to the head 13.
[0018]
The first and second belt conveyors 11 and 12 are provided to be rotatable forward and backward, and are plates to be coated placed on the belt 11A or 12A through a jig 16 in a substantially horizontal posture. By transferring the body P from one belt conveyor to the other belt conveyor, the paint P flowing through the lower slit of the head 13 is passed through the plate P so that the plate P can be coated. Has become.
[0019]
As shown in FIG. 2, the plate-shaped body P has a substantially square upper surface P1 and four cutting edges P2, P3, P4, and P5 that hang down through a straight ridge C extending in a substantially horizontal plane. It has a rectangular shape in plan view with
[0020]
The jig 16 has a support surface 16A (see FIG. 1) smaller than the plane size of the plate-shaped body P and is formed flat with a certain plate thickness. The jig 16 is used such that the jig 16 does not protrude from any of the cut surfaces P2 to P5 of the plate-shaped body P when viewed from the upper surface with the plate-shaped body P placed thereon.
[0021]
At the time of painting, as shown in FIG. 2 (A), the plate-shaped body P is placed on the first belt conveyor 11 in a state where the cut surfaces P3 and P4 or the cut surfaces P2 and P5 are substantially parallel to the curtain 17. Is done. Then, when this is transferred to the second belt conveyor 12 side, the plate-like body P passes through the curtain 17 together with the jig 16, thereby forming a first coating film on the upper surface P 1. Can be completed. After drying, the upper surface P1 is ground with sandpaper to smooth the upper surface of the plate-like body P and to reduce the coating thickness of the upper surface P1.
[0022]
Next, as shown in FIG. 2 (B), the first and second belt conveyors 11 and 12 are turned over, and the plate-like body together with the jig 16 is moved from the second belt conveyor 12 to the first belt conveyor 11 side. By transferring P, a second coating step of forming a coating film on the upper surface P1 of the plate-like body P can be performed, and thereafter, the plate-like body P that has been subjected to the coating treatment as a final product by drying is provided. Obtainable.
[0023]
Therefore, in such a coating method, even if the jig 16 passes through the curtain 17, the paint is not adhered to the jig 16, and thereafter, the plate-shaped body P is placed on the jig 16. Even if it is replaced or a new plate-shaped object P is placed, the paint does not adhere to the lower surface of the plate-shaped object P.
[0024]
As another coating method of the present invention, as shown in FIGS. 3 and 4, as the jig 16, a jig having a shape in which the support surface 16 </ b> A is inclined is used, and The jig 16 is set so that the extending direction of the jig 16 is approximately 45 degrees with respect to the transport direction of the plate-like body P, that is, approximately 45 degrees with respect to the surface of the paint curtain 17. It is set on the first belt conveyor 11 or the second belt conveyor 12 through the above, and thereby, the upper surface P1 and the cutting edges P2 to P5 can be painted.
[0025]
That is, as shown in FIG. 4 (A), at the time of painting, when the plate-shaped body P is arranged on the first belt conveyor 11 via the jig 16 and transferred to the second belt conveyor 12 side. Then, the plate-like body P passes through the curtain 17, and the first coating step of forming a coating film on the upper surface P1 and the two wood edges P2 and P3 on the curtain 17 side can be completed. . After drying, the upper surface P1 is ground with sandpaper to smooth the upper surface of the plate-like body P and to reduce the coating thickness of the upper surface P1.
[0026]
Next, as shown in FIG. 4 (B), the right and left positions of only the jig 16 are inverted, and the first and second belt conveyors 11 and 12 are inverted to transfer the first belt from the second belt conveyor 12 to the first belt. By transferring the plate-like body P to the conveyor 11 side, it is possible to perform a second coating step of forming a coating film on the upper surface P1 of the plate-like body P and the wood opening surfaces P4 and P5 of the curtain 17 side, After that, it is dried to obtain a plate-shaped body P which has been subjected to a coating treatment as a final product.
[0027]
According to such a method, the upper surface P1 and each of the cut surfaces P2 to P5 can be simultaneously coated, and the curtain 17 is passed through the plate-shaped body P in an inclined state. As compared with the method described above, the thickness of the coating film on the cut surfaces P2 to P5 can be increased while the thickness of the coating film on the upper surface P1 can be suppressed.
[0028]
【Example】
Next, the results of the present invention in which the upper surface P1 and the cutting edges P2 to P5 are coated using the coating device 10 will be described with reference to comparative examples.
[0029]
[Example 1]
MDF was used as the plate-shaped body P, and a polyester facer layer was provided on the upper surface P1 and the four wood-cut surfaces P2 to P5, and an enamel layer was provided on the surface to obtain a material.
Using the coating apparatus 10, the plate-shaped body P was placed on a jig serving as a support surface 16 </ b> A having an inclination angle of 0 °, and the cutout surfaces P <b> 2 and P <b> 3 were arranged so as to be approximately 45 ° with respect to the curtain 13. Then, the plate-shaped material P is transferred from the first belt conveyor 11 to the second belt conveyor 12 side, the clear resin paint flows down from the head 13, and the paint curtain 17 is passed through, so that the upper surface P1 and the cut surface P2, The first coating process was performed on P3. After drying for a predetermined time, the upper surface P1 was ground with # 320 sandpaper. Thereafter, the plate-like body P is transferred from the second belt conveyor 12 toward the first belt conveyor 11, and the plate-like body P is passed through the curtain 17 from the opposite side to the above, so that the upper surface P1 and the kiguchi A second coating process was performed on the surfaces P4 and P5. Then, a plate-shaped body P which was dried for a predetermined time and finished with an enamel mirror surface was obtained. When the obtained plate-like body P was visually observed, the surface smoothness could be visually recognized well, and the long wave value measured by using Wavescan Plus of Big Chemie Japan was 2.21, and the surface smoothness was measured. It was possible to obtain a coated plate-like body excellent in quality. Here, as the long wave value approaches "0", it indicates that the smoothing performance is more excellent. In addition, the coating material viscosity in Example 1 was 30 seconds, and the coating amount was 70 g / m ² . The belt speed was 70 m / min.
[0030]
[Example 2]
Instead of the polyester facer layer, a material made of a solid wood veneer was adhered to the MDF and a colored layer and a colored resin layer were provided on the surface of the plate.
The plate-like body P was coated using the coating apparatus 10 under the same conditions as in the first embodiment to obtain a plate-like body having a wood grain mirror finish.
When the obtained plate-like body P was visually observed, the surface smoothness was visibly recognized, and the long wave value was 0.70.
[0031]
The coating was performed under the same conditions as in the first and second embodiments by gradually increasing the inclination angle of the support surface 16A of the jig 16 up to 20 ° in increments of 5 °. The same result was obtained except for the relative change in the thickness of the coating on the surfaces P2 to P5. Incidentally, the coating thickness of the upper surface P1 at an inclination angle of 0 ° was 72 μm, and the coating thickness of the lip surfaces P2 to P5 was 17 μm, but the coating thickness of the upper surface P1 was 69 μm at 5 ° and 65 μm at 10 °. It was 62 μm at 15 ° and 57 μm at 20 °. On the other hand, the thicknesses of the coatings on the wood surfaces P2 to P5 were 20 μm, 22 μm, 24 μm, and 26 μm, respectively. That is, as the inclination angle increases, the difference between the thickness of the coating on the upper surface P1 and the thickness of the coating on the cut surfaces P2 to P5 is reduced.
[0032]
[Comparative Example 1]
After passing through the first coating step using the same material as in Example 1, the second coating step was performed without passing through the drying step and the grinding step, and drying was performed.
When the obtained plate-like body P was visually observed, the surface smoothness was not recognized, and the long wave value showed a value of 17.5, which was hard to recognize that the surface smoothness was good.
In addition, when the test was performed by changing the inclination angle of the jig 16 in the same manner as in the above-described embodiment, only the difference between the coating thickness of the upper surface P1 and the coating thickness of the cutting edges P2 to P5 was reduced.
[0033]
[Comparative Example 2]
After passing through the first coating process using the same material as in Example 2, the second coating process was performed and dried without passing through the drying process and the grinding process.
When the obtained plate-like body P was visually observed, as in Comparative Example 1, no surface smoothness was observed, and the long wave value also showed a value of 15.8.
In addition, in Comparative Example 2, an experiment was performed by changing the inclination angle of the jig 16 in the same manner as in the above-described embodiment, but the difference between the coating thickness of the upper surface P1 and the coating thickness of the cut surfaces P2 to P5 was reduced. It is just.
[0034]
As described above, the best configuration and method for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this.
That is, although the present invention has been particularly illustrated and described mainly with respect to a specific embodiment, without departing from the scope of the technical idea and the purpose of the present invention, the shape, material, A person skilled in the art can make various changes as necessary regarding the position or arrangement. For example, with reference to FIGS. 1 and 2, a description has been given of a direction in which the front edge of the front end in the moving direction is substantially parallel to the paint curtain 17. However, as illustrated in FIG. This also includes painting in an inclined orientation.
[0035]
【The invention's effect】
As described above, according to the present invention, a method of interposing a jig having a supporting surface smaller than the plane size of the plate-shaped body when coating the plate-shaped body is employed. Is prevented from being attached, whereby the inconvenience that the paint adheres to the lower surface of the plate-like body can be solved.
[0036]
Further, according to the method employing the method of drying and grinding the painted surface in the first painting process prior to the second painting process, the surface smoothness of the painted surface can be improved satisfactorily. There is no inconvenience that the uneven surface appears. In addition, a high gloss mirror finish can be achieved through the second coating process. Furthermore, the coating method using a jig provided with an inclined surface can also prevent the coating film on the top surface from becoming relatively thicker than the coating film on the wood opening surface. The inconvenience of causing a color tone difference due to a difference in coating film thickness depending on the color of the paint can also be solved.
[Brief description of the drawings]
FIG. 1 is a schematic side view of a coating apparatus to which a coating method using a jig having a constant thickness is applied.
FIGS. 2A and 2B are schematic plan views showing a coating method using the apparatus shown in FIG.
FIG. 3 is a schematic side view of a coating apparatus to which another coating method using a jig having an inclined support surface is applied.
FIGS. 4A and 4B are schematic plan views showing a coating method using the apparatus shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Coating apparatus, 11 ... First belt conveyor, 12 ... Second belt conveyor, 13 ... Head, 16 ... Jig, 16A ... Support surface, 17 ... Curtain of paint, P ... Plate, P1 ... Top surface , P2, P3, P4, P5 ... Kiguchi surface

Claims (5)

In the method of painting the upper surface of the plate-shaped body through a paint curtain,
Placing the plate-like body on a jig provided with a support surface smaller than the plane size of the plate-like body, and in this state, passing the jig and the plate-like body through the curtain to paint the upper surface. A method for coating a plate-like body, characterized by the following. In the method of painting the upper surface of the plate-shaped body and the surrounding edges by passing through a paint curtain,
The plate-shaped body is placed on a jig having a support surface smaller than the plane size of the plate-shaped body,
A plate, wherein the jig and the plate-like body are passed through the curtain in a state where the cut edge surface is arranged at an angle of approximately 45 degrees with respect to the curtain, and the upper surface and the cut edge surface are painted. How to paint the body. In the method of painting the upper surface of the plate-shaped body and the surrounding edges by passing through a paint curtain,
The plate-shaped body is placed on a jig having a support surface smaller than the plane size of the plate-shaped body,
A first method for painting the upper surface and the curtain-side edge of the curtain by passing a jig and a plate-like body through the curtain in a state where the edge of the edge is arranged at an angle of approximately 45 degrees with respect to the curtain. Coating process,
A drying step of drying the painted surface,
A grinding step of grinding the painted surface,
A second painting step of painting the plate-like body through a curtain in a direction opposite to the first painting step and painting the upper surface of the plate-like body and the opening on the curtain side, Method. The plate-like body according to claim 2 or 3, wherein the support surface is an inclined surface, and the jig passes through the curtain in a direction in which a front portion along the moving direction becomes a position gradually higher than a rear portion. Painting method. Claim 1, wherein the viscosity of the coating is 15 to 50 seconds, the coating amount is ^{50g / m 2 ~150g / m 2} , the relative movement velocity of the curtain and the plate-like body is 50m / min~100m / min 5. The method for coating a plate-shaped body according to any one of the above-described items 4 to 4.

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