JPS59118402A - Manufacture of decorative pasted flitch having no warpage - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a nine-piece thin decorative plate without warping.

Wall usage 2. Decorative plywood used for flooring, etc., is made by bonding a decorative veneer to the surface of a plywood base plate, and is commercially available in many thicknesses of 3 to 5 mm thick. Among such decorative plywood, so-called thin ones, especially those with a thickness of 3 m+n or 4 barrels, usually exhibit an upwardly warped state in which the surface side is concave.

The above-mentioned warpage is thought to be caused by the following reasons. In other words, plywood, which is decorative plywood, is made by gluing together an odd number of veneers.
For example, in the case of a 3-ply base plate, the front and back veneers of the front plate, stone plate, and back plate are made to have the same thickness, and these veneers are alternately stacked so that the fiber direction is orthogonal to each other. By forming it in this way, even if the wood expands or contracts due to changes in the moisture content of each veneer, the stress will be balanced with each other, resulting in a plywood base plate that is less prone to warping or twisting. It is said that it will be done.

However, when a decorative veneer is bonded to one side of the plywood base plate using an adhesive, moisture in the adhesive causes severe changes in the moisture content of the plywood base plate, especially the top plate. This effect would disrupt the above balance.

Conventionally, when using decorative plywood, thicker pieces were fixed to crosspieces or joists using a combination of adhesive and nails, so even if the wood warped slightly, it did not cause any problems during construction. However, thin products are usually attached directly to a smooth base material using adhesive or double-sided adhesive tape, and if there is any warping during that process, the edges may lift up. This caused problems in construction. Even in this case, it seems that there is no particular problem because it is possible to glue the construction misalignment while pushing the periphery in a convenient manner, but even after gluing, the periphery of the decorative flash base plate γj and the upward force that tries to return to its original state will continue to act, so the peripheral edge of the decorative plywood glued during use will be on the bottom). It will peel off and become a floating layer. For this reason, thin decorative plywood needed to be made to avoid warping as much as possible.

In general, in the case of unwarped plywood, the neutral axis passes through the center of the core root, and the tensile stress above and below it can be considered to be balanced. Therefore, the key to eliminating warping in decorative plywood is to predict how much tensile force will be generated by gluing the decorative veneer to the base plate, and then create a tensile force on the opposite side that balances this. That's fine.

In other words, if the neutral axis passes through the center of the decorative plywood, it is possible to make decorative plywood without warping.

Therefore, the inventor of the present invention has focused on the above-mentioned points, and as a result of various investigations, has achieved the present invention. That is, the inventor of the present invention formed the back plate of the 3-ply base plate to be thicker than the top plate so that the lower side of the plywood base plate had a lower tensile stress than the upper side, and also Washi paper is pasted on the back of the baseboard, and then water is sprinkled on the surface of the washi paper, and the shrinkage force of the washi paper caused by the evaporation of water is used to reduce the tensile force caused by adhering the decorative veneer to the plywood baseboard. The neutral axis passes through the center of the decorative burr plywood so that a decorative burr baseboard with no warping can be obtained, but even if there is warpage, the surface side will be convex and exhibit some downward curvature. It is something to do.

Next, as an example of the present invention, a method for manufacturing decorative flash plywood of three thicknesses will be described below.

First of all, carefully adjust the thickness of the back plate (13) of the top plate (11), heart root (1), and back plate (13) of the 3-braue board so that it is thicker than the top plate (jl). is 2~ than the top plate (11)
In order to increase the size by 35 times, the specific thickness of each deck is 0.5 to 0.6 for the top plate (1) and 1 for the core (12).
．． It has been found that when the back plate (13) is made to have a thickness of 1.1 to 1.2 mm and the back plate (13) has a diameter of 1.1 to 1.2 mm, a plate with a decorative H shape without warping can be produced.

After producing the plywood base plate (10) as described above, a decorative veneer (2
0) via a known thermosetting adhesive (a),
The pieces are bonded together by heat and pressure, and then left to cool day and night (Figure 1). As the decorative veneer (20), one formed in a marquetry pattern or the like by a known method may be used.

After that, the back surface of the base plate base plate (10) VC8 ~]Oζ2
After hot-pressing a heavy Japanese paper (30) using a known adhesive (1) and laminating it (Fig. 1, c), the surface of the washi paper (30) was sprayed with water evenly using a water sprinkler. Sprinkle it on the water and leave it for about two days and nights (Fig. 1, 2).

The amount of water to be sprayed, together with the water content in the adhesive (1) used for binding the Japanese paper (30), will be 2.5 to 3 times the water content in the adhesive (-). do it like this. J: When the water in the Japanese paper (30) evaporates due to searing, the Japanese paper (30) shrinks, and the shrinkage force of the Japanese paper (30) and the back plate (13) of the plywood base plate (10) are This combination of the fact that the thickness is thicker than the top plate (moon) creates stress in the decorative plywood that counteracts the warping, and therefore the neutral axis is the center of the decorative plywood. The decorative veneer (20) is glued to the plywood base plate (10).The stress generated by the cyano A decorative burr base plate with a slight downward curvature with a convex surface can be obtained without causing any problems in practical use. When the height of the warp was measured for the sample (object), it was found to be 3 feet.

When manufacturing decorative plywood, we consider all factors that affect warping, such as the shrinkage rate of the raw wood, the degree of shrinkage of the adhesive during hot pressing, the dryness of the surface, and the distribution of moisture content. It is difficult to hold the back board (13) exactly 1 to 35 times as thick as the top board (11), although it differs depending on the tree species. , decorative plywood can be manufactured such that the neutral axis passes through the center of the decorative plywood.

Generally, when manufacturing this type of decorative plywood, the base plate base plate (10) is formed with dimensions of 1835 x 930 (mm), and the decorative veneer (20) is placed on its surface in an arbitrary pattern. After manufacturing, the surface is further polished and painted, and then divided into three parts in the longitudinal direction, each having dimensions of 1818 rrvn x 303 mm. (40) is double-sided adhesive tape adhered to the back side of the decorative flashing base plate, (50) is double-sided adhesive tape (
A covering tape (40) is releasably attached to the surface of the tape (50), and during construction, the covering tape (50) is peeled off to expose the adhesive surface.

The decorative beam base plate manufactured as described above has no warpage or is warped downward, and there is no problem in practical use. ,
It does not peel off from the periphery.

Especially when pasting the double-sided adhesive tape (40) on the back side, it can be pasted simply by pressing it with your hands.
It can also be used to repair existing floors, walls, ceilings, etc. when they become dirty or damaged by pasting them directly onto the interior walls.

Furthermore, when used as a floor in a newly built house, various superior effects can be obtained compared to conventional thick (12 mm to 15 rmn thick) decorative plywood. In other words, for the base plate, ordinary plywood (12
mmJ, 'J-), roughly nail it to the joist, etc., and paste the decorative plywood (3mm thick) on top of this. It is possible to use a variety of materials, simplify construction, and reduce construction costs per unit area compared to conventional products. ■Unlike conventional products, there is no need to fit and join pieces that have been processed to have a grain finish, so there is no chance of treading. ■When constructing a building, you usually have to construct the floor, walls, and ceiling in that order.
Therefore, when constructing walls and ceilings, the floors that have already been constructed may become dirty or scratched, but when using decorative plywood obtained by the present invention,
It becomes possible to adopt a construction method in which the walls and ceiling are constructed at the stage where the walls and ceiling are constructed, and finally the decorative plywood is attached to the base material to finish the work, which eliminates the drawbacks of conventional construction methods. ■ Conventionally, for 15-thick decorative burr boards, a 1.2 to 1.3 mm thick veneer was used as the top plate of the plywood base plate, so the difference in thickness between the decorative veneer and the decorative veneer was extremely large. However, the decorative veneer tends to crack, and to prevent this, paper or cloth is interposed between the plywood base plate and the decorative deck, or a face plate is placed inside the base plate. Therefore, the cost was high, but since the thickness of the top plate of the plywood base plate can be made thinner with the decorative plywood obtained by the present invention, it can meet the decorative veneer regulations without the need for the measures required for conventional products. This will eliminate the occurrence of cracks.

[Brief explanation of drawings]

Figures 1 (A), (B), and (C) are side views showing the manufacturing method of the present invention in order, Figure 2 is a perspective view of the surface side of the product obtained by the same method, and Figure 3 is It is a partially cutaway perspective view of the back side same as the above. +101...Plywood base plate, (11)...Top plate, (12)
... Core root, (13) ... Back board, (20) ... Decorative board, (30) ... Japanese paper, (a) (1)) ... Adhesive. Patent applicant Kyodo Veneer Co., Ltd. Figure 1

Claims (1)

[Claims] 1 Among the top board (11), stone board (12), and back board (]3), make the back board (13) thicker than the top board (121) to produce a 3-ply plywood baseboard (10). process, applying a decorative veneer (20) to the surface of the base plate (10) via an adhesive (3)
and applying adhesive (1) to the back surface of the base plate (10).
]) After pasting the Japanese paper (30) through the paper, the Japanese paper (30)
A method for producing a decorative adhesive board without warping, which comprises the step of spraying water on the surface of the board.