JP5574564B2 - Decorative plate manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a decorative board suitable for use in flooring or wall material of a building such as a house, and in particular, produces a decorative board that is unlikely to undergo deformation such as warping or twisting during manufacturing or actual use. The present invention relates to a method for manufacturing a decorative board that can be manufactured with good performance.

  Conventionally, as described in Patent Document 1, for example, a wood composite board in which a wood fiber board such as MDF having high hardness is attached to the surface of a plywood is well known. Usually, a water-based adhesive such as urea resin or urea-melamine resin adhesive is applied to the surface of the plywood, and a wooden fiber board such as MDF is placed thereon and laminated, and this laminate is heated by a hot press device. It is manufactured by pressing and bonding.

  However, when such a wood composite board is manufactured, if the wood fiber board and the plywood are hot-pressed with a hot press device using a water-based adhesive such as urea-melamine resin adhesive, the moisture in the adhesive is removed from the plywood surface. As a result of the transition to the back of the wood fiber board or the moisture on the surface of the wood fiber board being dissipated and contracted by heat pressure, there is a problem that the wood composite board is likely to be deformed such as warping or twisting with its back side convex. It was.

  For this reason, in Patent Document 1, the fiber direction of the single plate on the front and back of the plywood is set as the longitudinal direction, and the thickness of the front side single plate is set to be thicker than the thickness of the back side single plate. It is devised so that deformation such as warping and twisting does not occur during hot pressing.

  However, such a method of Patent Document 1 has a problem that the configuration of the obtained wood composite board is extremely limited. Furthermore, since it is premised on hot press bonding with a hot press apparatus, there is a problem that a large-scale production facility is required and productivity is low due to batch processing.

  Conventionally, as a single plate constituting plywood, southern hardwoods such as lauan timber, which has a small and uniform density difference between early and late wood, and has no defects such as missing nodes, have been widely used. From the viewpoint of depleting resources and protecting the global environment in recent years, the difference in the density of early and late wood such as planted trees, especially Radiata Pine, domestic todomatsu, larch, cedar, etc. is clear and air-dried. It is desired to make full use of a plywood made of a single plate made of light conifers having a specific gravity of 0.5 or less as a base material for a wood composite board.

  However, as described in, for example, Patent Document 2, a plywood using a veneer having a large density difference between early and late woods, or a planted wood veneer that is light and has many defects such as missing nodes is used as a base material. As shown in FIGS. 3 and 4, the wood composite board is compressed by the hot pressure generated by the hot press device during the production of the wood composite board. When the surface of the wood fiber board 22 on the material portion 26 and the wood fiber board 22 on the cut-out node portion 23 is slightly swollen 25 and the convex portion 32, and further the decorative sheet material 31 is stuck on the surface. There has been a problem that such bulges 25 and convex portions 32 are raised on the surface of the decorative sheet material 31 and the appearance of the decorative plate is remarkably impaired.

For this reason, it is possible to grind the surface of the formed wood composite board and then apply the decorative sheet material to form it on the decorative board, but it is possible to adjust it to the degree of the individual bulges 25 and convex parts 32 Since there is a need to grind excessively assuming the maximum swell, there is a problem that the yield and productivity become very bad, and the obtained wood composite board is also hard on the surface of the bent wood fiber board As a result of grinding the part, there was a problem that the hardness of the surface was insufficient.
JP 2006-192817 A JP 2002-187103 A

  The present invention has been made in view of the above problems, and a decorative board in which a decorative sheet material is attached to the surface of a wood composite board formed by attaching and integrating a wood fiber board to the surface of a plywood is warped or twisted during manufacture. There is provided a method for manufacturing a decorative board capable of manufacturing a decorative board that is less likely to be deformed such as warping or twisting due to environmental changes such as humidity during actual use. For the purpose.

  In addition, the present invention provides a plywood as a base material for a wood composite board, a softwood single board having a large density difference between early wood and late wood, a single board made of wood with many omissions, or a light planted wood single piece. In the case of using a plate, it is possible to remarkably suppress the occurrence of blisters and protrusions that are likely to occur on the surface of the wood composite board, and the grinding process can be carried out without excessively grinding the surface of the wood composite board as in the past. An object of the present invention is to provide a method for manufacturing a decorative board, which can be manufactured with good productivity by omitting or grinding lightly to a normal degree, so that the decorative face does not bulge and the protrusion of the convex part does not occur. To do.

In order to achieve the above object, the method for producing a decorative board according to claim 1 has a thickness of 1.0 to 3.0 mm, a specific gravity of 0.6 to 1.0, and a moisture content of 4 in advance. A wood fiber board adjusted to ˜8 % by weight , a thickness of 9.0 to 9.5 mm, a number of laminated single plates of 4 or 5 plies, a specific gravity of 0.5 or less, and a moisture content of 8 in advance. Plywood adjusted to ˜14% by weight is laminated via a moisture curable urethane resin hot melt resin adhesive, and the moisture curable urethane resin hot melt resin adhesive is in a molten state. feed rate among a roll press 20 to 30 m / min, by applying cold as a pressure 10-20 kg / cm ^2, the wood fiber board is formed in wood composite board which is integrally bonded to the surface side, and then the wood quality composite board And sticking a reinforcing sheet material to the back side of the wood A decorative sheet material is adhered to the surface side of the composite plate.

Thus, in the invention of claim 1, the wood fiber board and the plywood are instantaneously fed at a feed speed of 20 to 30 m / min and a pressure of 10 to 20 kg / cm ^{2 by} a roll press using a moisture-curable urethane resin hot melt resin. since cold pressed by adhering to, it is possible to continuously produce compared with the case of hot-pressing in a hot press using a conventional manner aqueous adhesive good productivity, also, moisture in the adhesive Therefore, it is possible to manufacture a wood composite board that is free from deformation such as warping and twisting. And since the reinforcing sheet material is stuck to the back side of this wood composite board and the decorative sheet material is stuck to the front side, a decorative board free from deformation such as warping and twisting can be manufactured. .

Furthermore, wood fiberboard and plywood thickness, air-dried specific gravity, plywood number of plies, it by adjusting the wood composite board manufacturing before water content adjustment as described above, warpage to a further, small deformation distortion, etc. A decorative board can be manufactured. In addition, even when using light plywood made of planted wood veneer or plywood with defects such as cut-off joints, the surface of the decorative sheet material can be used without excessively grinding the surface of the wood composite board that is the base material. Therefore, it can be formed on a decorative board with high design that does not bulge or protrude.

  As described above, the present invention can produce a decorative board that does not undergo deformation such as warping or twisting during production or use with high productivity. In addition, even when using a veneer with a defect such as an afforestation tree or a conifer, a veneer that does not float up as a convex or swollen on the surface of the decorative sheet material, even when the veneer part or breakthrough of the veneer is used, It can be manufactured with high productivity without excessively grinding the surface of the wood composite board.

  Hereinafter, the manufacturing method of the decorative board B which is embodiment of this invention is demonstrated based on FIG. 1, FIG. Note that the present invention is not limited to the description of the present embodiment.

  FIG. 1 shows a manufacturing process of a wood composite board A used as a substrate of a decorative board B, and FIG. 2 manufactures a decorative board B by attaching a decorative sheet material 10 to the surface of the obtained wood composite board A. The manufacturing process of the decorative board B is shown.

  In FIG. 1A, reference numeral 1 denotes a rectangular plywood that is a base material of the wood composite board A, and is configured so that the direction of a single board wood fiber on the front and back is substantially the length direction of the plywood 1. ing. The plywood 1 is adjusted in advance so that the moisture content is 8 to 14% by weight.

  Here, when the decorative board B is used as a standard decorative floor board having a thickness of 12 mm, the number of single plies of the plywood 1 as the base material is 4 or 5 plies, and the thickness of the plywood 1 is 9.0. It is preferable to use a material having a thickness of about 9.5 mm. In addition, when the moisture content of the plywood 1 is less than 8% by weight, it is not preferable because it absorbs moisture and easily expands in the use state after being formed on the decorative board B, and when it exceeds 14% by weight, moisture is dissipated. This is not preferable because it tends to shrink. By preliminarily adjusting the moisture content of the plywood 1 to 8 to 14% by weight, which is higher than the moisture content of the wood fiber board 2 to be described later, the balance between expansion and contraction with the wood fiber board 2 is kept good, It is possible to satisfactorily prevent the warp and twist from occurring in the formed wood composite board A.

  Moreover, the tree species of the single board which comprises the plywood 1 are not specifically limited, A various thing can be used. In particular, in the present invention, a soft and low-hardness tree species, a tree species that tends to warp or twist, a tree species that has many defects such as missing nodes, and a tree species that has a large hardness difference between early and late wood, such as conifers whose use range was limited. Plywood 1 is composed of tree species such as Japanese Todomatsu, larch, cedar, spruce, radiata pine, northern larch, poplar, acacia hybrid, acacia mangeum, falkata, eucalyptus, rubber, etc. It can be used as a single plate or a single plate constituting a part of the plywood 1.

  In FIG. 1A, reference numeral 2 denotes a wood fiber board that is bonded to the surface of the plywood 1. The wood fiber board 2 has a thickness of 1.0 to 3.0 mm and an air-dry specific gravity (hereinafter, the specific gravity is referred to as air-dry specific gravity in the present invention) 0.6 to 1.0. Yes, a water content adjusted to 4 to 8% by weight in advance can be suitably used.

  If the thickness of the wood fiber board 2 is less than 1.0 mm, the strength such as hardness is insufficient, which is not preferable. If the thickness exceeds 3.0 mm, the influence of the wood fiber board 2 becomes too large to be formed. The wood composite board A is not preferable because deformation such as warpage is likely to occur. By setting the thickness of the wood fiber board 2 to 1.0 to 3.0 mm, a single board constituting the plywood 1 is light and low in hardness like an afforestation tree, and has a defect such as an omission. Even when used, good hardness can be imparted and deformation such as warpage can be prevented.

  Further, when the moisture content of the wood fiber board 2 is less than 4% by weight, it absorbs moisture in the use environment and easily expands, and when it exceeds 8% by weight, the moisture dissipates and easily contracts. In such a case, the wood composite board A may be deformed such as warping, which is not preferable. From such a viewpoint, it is preferable that the moisture content of the wood fiber board 2 is adjusted in advance to be 4 to 8% by weight.

  Thus, by setting the moisture content of the wood fiber board 2 to be in the above range in advance and adjusting the moisture content to be lower than the moisture content of the plywood 1, the formed wood composite board A is Even during its use, it is possible to satisfactorily prevent warping and twisting.

  Further, if the specific gravity of the wood fiber board 2 is less than 0.6, it is not preferable because the hardness is low and the surface is easily damaged, and if it exceeds 1.0, it is not preferable because the workability is poor and the cost is increased.

  Further, when a thin fiberboard 2 having a thickness of less than 2.0 mm is used as the wood fiberboard 2, for example, the wood fiberboard 2 having a thickness of 3.0 mm is divided into two in the thickness direction to be approximately 1.5 mm. It is also possible to use a thicker layer, or to further reduce the thickness by sanding the divided surface.

Next, as shown in FIG. 1 (b), a hot melt resin coating apparatus 4 is used for either one or both of the front surface of the plywood 1 adjusted in water content, the back surface of the wood fiber board 2, or both. Hot melt resin adhesive 3 is applied. The application amount of the adhesive 3 is not particularly limited, but is usually about 50 to 100 g / m ² . In addition, in FIG.1 (b) which shows this embodiment, the example which apply | coated the said hot-melt resin adhesive 3 to the back surface of the wood fiber board 2 is shown. That is, the molten hot-melt resin adhesive 3 is applied to the back surface of the wood fiber board 2 by the application roll of the coating device 4 while being conveyed with the back surface side of the wood fiber board 2 facing upward. In addition, not only this but the hot-melt resin adhesive 3 can also be apply | coated to the surface of the plywood 1, or it can also apply | coat to both the back surface of the wood fiber board 2, and the surface of the plywood 1.

  Here, as the hot-melt resin adhesive 3, a moisture-curing urethane resin hot-melt adhesive (PUR hot-melt adhesive) that has excellent adhesive strength and can be cured well without heating can be suitably used. . Unlike the water-based urea-melamine resin adhesive or the like normally used for this kind of application, such a hot melt resin adhesive 3 does not contain moisture, so the plywood 1 and the wood fiber board 2 are bonded and combined. When this is done, moisture in the adhesive does not permeate the surface of the plywood 1 or the back surface of the wood fiber board 2, and the moisture content of the surface of the plywood 1 or the back surface of the wood fiber board 2 is not affected. Moreover, since it is not necessary to heat for hardening, it can prevent that curvature arises by shrinkage | contraction of the wood fiber board 2 surface by heating.

  Next, as shown in FIG. 1 (c), the wood fiber board 2 with the hot melt resin adhesive 3 applied on the back surface is placed with the back surface facing upward, and the front surface of the plywood 1 is in contact with the back surface. The plywood 1 is placed on the laminate 5.

  Then, as shown in FIG. 1 (d), while the laminate 5 is continuously conveyed, while the hot melt resin adhesive 3 is in a molten state, one or a plurality of continuously installed units are provided. The laminate 5 is cold-pressed by the roll press device 6 and the plywood 1 and the wood fiber board 2 are bonded and integrated, and then cured and inverted to produce a wood composite board A as shown in FIG. .

Here, the pressing condition of the laminate 5 by roll press device 6 conveys at a speed 20 to 30 m / min Feed The product layer was 5, cold the laminate 5 by roll press device 6 at 10-20 kg / cm ² By pressing, the wood composite board A shown in FIG. 1 (e) can be manufactured continuously and with high productivity.

  As described above, since the roll press device 6 is cold-pressed, the moisture of the plywood 1 and the wood fiber board 2 is diffused as in the case of a hot press under a high temperature as conventionally performed. In addition, the manufactured wood composite board A is not deformed such as warpage. In addition, there is an advantage that the heating equipment can be omitted and the production can be performed at a high production speed.

  Moreover, even when using a coniferous plantation tree that is relatively light and has a difference in hardness between the early and late woods and has knots on the veneer constituting the plywood 1 Since the plywood 1 and the wood fiber board 2 are adjusted in water content in advance and are cold-pressed by the roll press device 6 using the hot melt resin adhesive 3 not containing moisture, the plywood 1 is integrated. It is possible to reduce the fact that the traces of the hard single material and the traces of the breakout of the single plate constituting the swell are raised on the surface of the wood composite board A.

  Such relief effect of the relief phenomenon is that the moisture content of the plywood 1 and the wood fiber board 2 is reduced to 14% by weight or less and 8% by weight or less in advance to reduce the compressive deformability, and does not contain moisture. By using the hot melt resin adhesive 3, the moisture in the adhesive does not transfer to the plywood 1 or the wood fiber board 2 as in the prior art, so that the compressive deformation does not increase, and the instantaneous cold pressure by the roll press Therefore, the compression deformation is very small, and the phenomenon that the trace of the compressed early wood and the trace of the break-through node return after the decompression is reduced, and the surface of the wood composite board A is raised to the wood fiberboard layer. Can be reduced. For this reason, the decorative board B which does not produce the above-mentioned embossing phenomenon can be manufactured by light grinding to an ordinary level without excessively grinding the surface of the wood composite board A.

  Therefore, the obtained wood composite board A is not warped or twisted, and the surface of the single board constituting the plywood 1 and the traces of the missing nodes do not rise strongly on the surface. There is no need to grind, and in the next step, the decorative sheet material 10 can be satisfactorily adhered to the wood composite board A with good productivity.

2A shows a wood composite board A ′ obtained by sticking the reinforcing sheet material 11 to the back surface of the wood composite board A obtained in the above step. Here, as the reinforcing sheet member 11, a thin wood veneer having a thickness of about 0.15 mm to 0.60 mm, reinforced paper, resin-impregnated paper, or the like can be used. Moreover, the sticking of the reinforcing sheet material 11 to the back surface of the wood composite board A ′ is performed by applying a melamine resin adhesive, for example, at a temperature of 110 to 120 ° C. and a pressure of 5 to 7 kg / cm ² by hot pressing. For about 30 to 50 seconds.

  Next, the surface of the wood composite board A ′ obtained by sticking the reinforcing sheet material 11 on the back surface is lightly ground with a sander attached with paper having a roughness of about 180 to 240 to adjust the surface. . The surface of the wood composite plate A ′ can be ground before the reinforcing sheet material 11 is adhered to the back surface.

Next, as shown in FIG.2 (b), the decorative sheet material 10 is stuck on the surface of obtained wood composite board A '. Here, as the decorative sheet material 10, a veneer having a thickness of 0.15 to 0.60 mm, a synthetic resin decorative sheet such as polyolefin resin, decorative printing paper, resin-impregnated decorative printing paper, or the like can be used. Moreover, the sticking of the decorative sheet material 10 to the surface of the wood composite board A ′ is performed, for example, by applying a melamine resin adhesive, and at a temperature of 110 to 120 ° C. and a pressure of 5 to 7 kg / cm ² with a hot press. For about 30 to 50 seconds.

  Here, after grinding the surface of the wood composite board A ', the decorative sheet material 10 can be bonded to the front surface and the reinforcing sheet material 11 can be bonded to the back surface by hot pressing at the same time.

  In this way, the decorative sheet B shown in FIG. 2C is manufactured by sticking the decorative sheet material 10 to the surface of the wood composite board A '. And in this manufacturing method of the decorative board B, the decorative board B can be manufactured with high productivity without deformation such as warpage and without a lifting phenomenon caused by a missing joint.

  The present invention relates to a technology for producing a decorative board based on a wood composite board that effectively uses a plantation tree or the like that is a light renewable resource, with high productivity without warping, and for the global environment. The industrial applicability is also high in terms of contributing to this.

Explanatory drawing of the manufacturing process of the wood composite board A which is a base material of the decorative board B which is embodiment of this invention. Explanatory drawing of the manufacturing method of the decorative board B which is embodiment of this invention. Explanatory drawing of the lift which arises in the conventional method. Explanatory drawing of the lift which arises in another conventional method.

A, A 'wood composite board B decorative board 1 plywood 2 wood fiber board 3 hot melt resin adhesive 4 hot melt resin coating device 5 laminate 6 roll press device 10 decorative sheet material 11 reinforcing sheet material

Claims (1)

A wood fiberboard having a thickness of 1.0 to 3.0 mm, a specific gravity of 0.6 to 1.0, and a moisture content of 4 to 8% by weight, and a thickness of 9.0 to 9 .5mm, plywood with 4 or 5 ply laminates, specific gravity of 0.5 or less, and moisture content of 8-14% by weight previously bonded to moisture-curing urethane resin hot melt resin Laminating through the agent,
Feed rate The laminate was a roll press While the moisture-curable urethane resin-based hot melt resin adhesive in a molten state 20 to 30 m / min, by applying cold as a pressure 10-20 kg / cm ^2, the surface side Formed into a wood composite board with wood fiber board bonded together,
Next, a decorative sheet material is attached to the back surface side of the wood composite board, and a decorative sheet material is attached to the front surface side of the wood composite board.

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