JPH0335082B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a decorative board made of natural wood veneers, and in particular, its purpose is to produce a decorative board made of softwood such as pine, cedar, or cypress, which has a low surface hardness and is suitable for use as a flooring material. To provide a manufacturing method.

Among conventional natural wood veneer decorative boards, the flooring material is made of hardwood veneers such as cherry, oak, and rosewood, which have a high hardness, and after being attached to a substrate such as plywood, amino alkyd resin or urethane resin is used. It was most commonly manufactured by overcoating it with a transparent paint.

On the other hand, with the diversification of hobbies, not only conventional hardwoods but also softwood veneers such as pine, cedar, and cypress are being used as floor surface materials. However, like hardwood veneers, softwood veneers have drawbacks such as being easily damaged and dented because the spring wood, which makes up most of the veneer, is soft if only a transparent paint is applied. For this purpose, softwood veneers are impregnated with synthetic resin liquids such as unsaturated polyester and methyl methacrylate under reduced pressure and pressure, and then bonded to the substrate under heat and pressure, and the veneers are made into WPC.
(Wood plastic combination) type flooring material, or by thermo-pressing transparent impregnated paper impregnated with melamine, polyester, diallyl phthalate resin, etc. onto the surface of a veneer.

However, manufacturing veneer WPC-type decorative laminates requires a large amount of resin impregnation equipment, and the veneer is thin, about 2.0 mm or less, so as the impregnated resin hardens, it becomes extremely brittle. It will break easily. In addition, in order to be able to reuse the remaining liquid after impregnating the veneer with synthetic resin liquid, it is necessary to keep the amount of curing agent and curing accelerator as small as possible and to keep the molecular weight of the resin small. Bonding a board to a board by heat and pressure requires high temperatures and a long time, which results in poor work efficiency and tends to deteriorate the material of the veneer.

On the other hand, the method of hot-pressing transparent impregnated paper onto the surface of a veneer, as described in JP-A-50-76208, involves impregnating thin paper with synthetic resin and then heating and drying it to form impregnated paper. , the thermosetting reaction of the synthetic resin has been accelerated and its molecular weight has become extremely large, so even if it is then layered onto a veneer and hot-press molded, the synthetic resin will harden in a short time and the fluidity of the molecules will decrease. Badly, it is difficult to penetrate between the veneers.

Therefore, the adhesion force between synthetic resin and veneer is easily affected by the moisture content and smoothness of the veneer or substrate. For example, if the moisture content of the veneer exceeds about 10%, poor adhesion may occur, or the synthetic resin layer may It tends to cause cloudiness, uneven flow, and silvery eyes.

As described above, according to the conventional methods, it has been difficult to obtain a natural wood veneer decorative board that is satisfactory in terms of performance.

Therefore, after studying the above problems, we have completed the method of the present invention, which is satisfactory in terms of both performance and appearance.

The present invention uses a low-molecular thermosetting adhesive with good permeability on the surface of commonly used substrates such as plywood and particle board, or an adhesive made of the same synthetic resin as the synthetic resin liquid applied to the veneer in a later process. The veneers are layered through the veneer, then a transparent or colored transparent thermosetting synthetic resin liquid is applied to the surface of the veneer, and a sheet that becomes transparent when the synthetic resin permeates is layered on top of the veneer, and then laminated from there. This is a method for manufacturing a decorative veneer board in which adhesive resin molecules and overcoat synthetic resin molecules are infiltrated into the veneer and into the sheet and are integrated by heat-pressing the body at the same time.

In other words, the most distinctive features of the present invention are a highly permeable thermosetting adhesive applied to the surface of a common substrate, and a thermosetting synthetic resin liquid applied directly to the surface of the veneer, together with a sheet stacked on top of it. Pressure molding allows the adhesive resin molecules and synthetic resin molecules to penetrate into the veneer and into the sheet and harden it, forming a thick synthetic resin layer on the surface of the veneer as the veneer becomes WPC.

The present invention will be explained in detail with reference to the drawings.

Figure 1 shows a cross-sectional view of a veneer-covered decorative flooring material manufactured by the method of the present invention, and Figure 2 shows a veneer-covered decorative flooring material manufactured by hot-pressing conventional resin-impregnated paper for comparison. A cross-sectional view of the decorative flooring material is shown.

1 is a substrate, which uses commonly used substrates such as plywood, particle board, hardboard, asbestos slate board, and metal plate.

2 is an adhesive with good permeability, and veneer 3 is used during hot pressure molding.
It is used to penetrate the inside of the substrate and to attach the veneer 3 to the substrate 1.

If the adhesive 2 is made of the same synthetic resin as the transparent or colored transparent thermosetting synthetic resin liquid 4 applied to the veneer 3 in a later process, it will penetrate into the veneer from above and below. The adhesion of synthetic resins that harden with each other is good, and low-molecular thermosetting synthetic resins such as urea resin have good permeability into the veneer, both of which improve the strength of the veneer.

3 is a veneer made by peeling natural wood to a thickness of about 0.2 to 2.0 mm, and then laminating many natural wood veneers with adhesive, so that the adhesive layer forms a wood grain pattern. A thinly peeled veneer or the like, especially a veneer obtained from a coniferous tree such as pine, cedar, or cypress, is preferable.

Note that the surface of the veneer 3 may be appropriately colored with dye or pigment.

4 is a transparent or colored transparent thermosetting synthetic resin layer made of unsaturated polyester resin, melamine resin, amino alkyd resin, diallyl phthalate resin,
Acetoguanamine resin, benzoguanamine resin,
Use urethane resin, etc. By adding an appropriate coloring agent to the synthetic resin 4 and making it transparent, it is possible to impart depth of color to the decorative board.

The viscosity of the four synthetic resin liquids is preferably as high as 0.5 poise or higher so that a large amount can be applied onto the veneer 3.

5 is a sheet that becomes transparent when the synthetic resin 4 permeates, and is usually called overlay paper or slightly colored color overlay paper and weighs 10 to 40 g/
m ² Japanese paper or rayon paper, or 23-30g/
Use tissue paper wet-woven fabric, glass fiber mixed paper, etc. of about ² m2.

According to the method of the present invention, as is clear from FIG.
The resin penetrates into the interior from the upper and lower surfaces respectively, and is bonded inside the veneer 3 to form WPC, thereby not only improving the hardness of the veneer 3 but also greatly improving the adhesion between the synthetic resin 4 and the veneer 3. I can do it.

The reason for this is that, as mentioned above, in the conventional method using resin-impregnated paper (Fig. 2), the synthetic resin 6 is applied once to the thin paper 5.
Since the synthetic resin 6 is impregnated with a veneer and then heated and dried to form impregnated paper, the thermosetting reaction of the synthetic resin 6 is accelerated and the molecular weight becomes extremely large. It hardens over time, and the six molecules of synthetic resin have poor fluidity and are difficult to penetrate between the three veneers. Therefore, if there is a slight adhesion inhibiting factor such as moisture in the veneer 3, poor adhesion may occur, and uneven thickness of the decorative substrate may cause uneven flow of the resin or graininess.

However, in the method of the present invention, the highly permeable adhesive 2 and the synthetic resin 4 liquid are applied to the surface of the substrate 1 and the surface of the veneer 3, so it is possible to use resins each having a small molecular weight.

Next, the viscosity can be controlled freely by adjusting the amount of solvent added to the adhesive or synthetic resin liquid. Furthermore, by adjusting the amount of curing agent or curing accelerator added to the adhesive or synthetic resin, the curing time of the adhesive or synthetic resin can be adjusted freely, which is necessary for the adhesive or synthetic resin molecules to penetrate into the veneer. It is possible to select a suitable heat-pressing time, and the adhesion between the veneer 3 and the adhesive 2, the synthetic resin 4, and even the sheet 5 can be greatly improved compared to conventional resin-impregnated paper heat-press products.

In addition, since the amount of synthetic resin 4 that adheres to the veneer 3 and determines the surface performance of the decorative laminate is reduced by interposing the sheet 5 on the surface, it is different from the conventional decorative flooring material in which synthetic resin paint is applied on the veneer 3. It can be easily made in large amounts compared to the above, and the surface performance of the decorative board can be greatly improved.

Moreover, since the four synthetic resin layers of the present invention are reinforced by the fibers of the sheet 5, there is a decorative board that is simply a conventional veneer 3 coated with synthetic resin paint, and a WPC type in which the veneer 3 is impregnated with synthetic resin. It has features such as no cracking or chipping compared to decorative boards.

Next, examples of the present invention will be described.

Example (1) After applying 70 to 80 g/m ² of polyester resin adhesive to the surface of a 12 mm thick plywood, a 0.6 mm thick Japanese pine veneer was layered. Next, the top surface of the veneer is colored with a yellow dye, and then 100 to 120 g/m ² of a resin solution containing cobalt naphthenate and peroxide is applied to an unsaturated polyester resin with a viscosity of 1 to 2 poise. Layer a piece of thin paper weighing 23g/ ^m2 on top of the resin layer, insert it between hot press plates and press at 10-12cm.
Kg/cm ² , temperature 130 to 135° C., and pressure molding for 5 minutes to obtain the desired flooring material.

Example (2) After applying 70 to 80 g/m ² of urea resin adhesive to the surface of particle board with a thickness of 15 mm, a cedar board veneer with a thickness of 0.4 mm was layered. Then apply a viscosity of 0.5 to the top surface of the veneer.
Apply 200 to 230 g/m ² of a resin liquid containing ~1 poise diallyl phthalate resin and BPO, layer transparent paper weighing 20 g/m ² on top of the resin layer, insert it between hot press plates, and apply pressure. 8-10Kg/cm ² , temperature
Pressure molding was carried out at 130 to 135°C for 6 to 8 minutes to obtain the desired cedar veneer decorative flooring material.

As described above, according to the present invention, a veneer is converted into WPC using a very simple method, and a thick thermosetting synthetic resin layer is formed on the surface of the veneer, which is reinforced with thin paper fibers and strongly adheres to the veneer. Because it can be done, it has the effect of being able to manufacture veneer-laminated decorative boards with excellent surface performance at low cost.

[Brief explanation of the drawing]

FIG. 1 shows a sectional view of a flooring material according to an embodiment of the present invention. FIG. 2 shows a cross-sectional view of a conventional resin-impregnated paper overlay flooring. 1...Substrate, 2...Adhesive, 3...Single board, 4...
...Thermosetting transparent synthetic resin, 5... Sheet.

Claims (1)

[Claims] 1 Lay the veneers together using a commonly used low-molecular thermosetting adhesive with good permeability on the surface of the substrate, or an adhesive made of the same synthetic resin as the synthetic resin liquid applied to the veneer in a later process, and then By applying a transparent or colored transparent thermosetting synthetic resin liquid to the surface of the veneer, layering a sheet on top of which the synthetic resin permeates and becomes transparent, and then simultaneously thermo-pressing the laminate. A method for producing a decorative veneer board, which is characterized by integrating adhesive resin molecules and overcoating synthetic resin molecules into the veneer and sheet by penetrating and curing them.