JPH05269705A - Manufacture of decorative plate - Google Patents

Abstract

PURPOSE:To manufacture efficiently a synthetic-resin-infiltration-treated decorative plate wherein impregnation of a synthetic resin solution is performed swiftly and it is free from generation of a blur and has favorable decorative properties. CONSTITUTION:An adhesive agent layer 2 which has made a film is provided on a ligneous base 1 and after a lumber veneer 4 is superposed upon the adhesive agent layer 2 which has made the film through a coating layer 3 of an additive polymerization type synthetic resin solution which possesses viscosity of 200-30,000cps and viscosity at a hot press temperature becomes 100cps or lower and hot press treatment is performed by a press, through which infiltration of the synthetic resin solution into the lumber veneer 4 is made easy and after the infiltration, the synthetic resin solution is solidified immediately under a holding state without streaming the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a decorative board in which a wood veneer is bonded and integrated on a wooden substrate and at the same time a synthetic resin liquid is immediately impregnated and cured in the wood veneer. is there.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a decorative board which is obtained by laminating synthetic resin-impregnated single plates on a wooden substrate and integrating them, for example, as disclosed in Japanese Utility Model Publication No. 60-286610 Laminated wood veneer on the board,
After bonding, apply synthetic resin solution on the veneer and impregnate it,
Known methods include a method of curing, a method of impregnating a wood veneer with a synthetic resin solution and curing the veneer to form a decorative veneer, and adhering and integrating the decorative veneer on a wooden substrate.

[0003]

However, according to the former method, the replacement of the air inside the veneer with the synthetic resin solution is not successful simply by coating the veneer with the synthetic resin solution. Without it, the synthetic resin liquid cannot be sufficiently impregnated into the inside of the veneer, and although the surface layer seems to be treated at first glance, it is not sufficiently impregnated into the inside. A problem also occurs in terms of strength, and in the latter method, the synthetic resin liquid is once injected into the wood veneer, and the hardening treatment is performed, and this is then adhered onto the wood substrate. It is possible to fully impregnate the inside of the veneer, but the workability is poor and it takes a long time for production.
There was a problem that it was not suitable for mass production.

On the other hand, in order to improve the productivity, an adhesive and a synthetic resin solution are sequentially applied onto a wooden substrate, and then the wood veneers are superposed and subjected to heat-pressing treatment, so that the synthetic resin solution for the wood veneers. Although a method of adhering and integrating the wood veneer and the wooden substrate at the same time as the impregnation of the synthetic resin solution has been developed, there is a risk that the synthetic resin solution may be cured before the hot pressing after the preparation of the synthetic resin solution. Not only there is a case where the synthetic resin liquid is impregnated into the wooden substrate side when hot pressed, or the synthetic resin liquid impregnated into the wood veneer flows out from the wood veneer due to its good fluidity. However, there is a problem that the amount of impregnation decreases and the desired strength and cosmetic properties cannot be obtained. It is an object of the present invention to provide a method for manufacturing a decorative board that can completely eliminate such problems.

[0005]

[Means for Solving the Problems] Necessary conditions for achieving the above object are that the wood veneer is sufficiently impregnated with the synthetic resin liquid, and that the impregnated synthetic resin liquid flows out of the wood veneer. It is to cure without doing. Therefore, in the method for manufacturing a decorative board of the present invention, first, an adhesive is applied on a wooden substrate, and then the adhesive is heated to form a film. The term "film formation" refers to a state in which a film-like layer is formed by polymerization, drying or the like, but has adhesive performance.
Then, on this film-forming adhesive layer, a wood single layer is applied through a coating layer of an addition polymerization type synthetic resin liquid having a viscosity of 200 to 30,000 cps and having a viscosity at a hot press temperature of 100 cps or less. Laminate the boards and heat and pressurize them in the range of 100 to 140 ° C to reduce the resin viscosity, and impregnate and harden the synthetic resin solution into the wood veneer to bond the wood veneer onto the wooden board. It is characterized by being integrated.

In the above method, as described in claim 2, an addition polymerization type synthetic resin liquid may be applied to the surface of the wood veneer, and further, as described in claim 3, The kick-off temperature of the initiator added to the addition polymerization type synthetic resin liquid is preferably 100 ° C or lower.

[0007]

Since the film-formed adhesive layer is provided on the wooden substrate, when a wood veneer is laminated with a synthetic resin liquid having an appropriate coating thickness on it and subjected to heat-pressing treatment, the synthetic resin liquid is applied. Is prevented from being absorbed by the wood substrate side by the adhesive film forming layer, so that it permeates toward the wood veneer intensively. At this time, the viscosity of the synthetic resin liquid decreases due to heating, the fluidity increases, and the wood veneer is easily impregnated. Immediately after the impregnation, the initiator immediately starts the reaction so that the synthetic resin liquid becomes the wood veneer. Hardens without spilling from.

[0008]

EXAMPLE Next, referring to FIG. 1, an example of the present invention will be described in detail. First, in FIG. 1, an adhesive is applied to the entire upper surface of a wood substrate 1 such as plywood, particle board, hard board having an appropriate thickness, The adhesive is formed into a film by an appropriate means such as heating to form a film forming adhesive layer 2 having a thickness of 30 μm or more.

As a method for forming an adhesive film, vinyl acetate,
In the case of an aqueous emulsion adhesive such as a vinyl acetate-acrylic copolymer, after the application on the wooden substrate 1, the water in the adhesive is removed by heating or other means, and the emulsion is destroyed to promote the polymerization. The adhesive layer 2 is formed into a film. In the case of a solvent-based adhesive such as diallyl phthalate (DAP) or polyester, for example, a polyester-based adhesive forms the film-forming adhesive layer 2 by partially performing a copolymerization reaction of a resin and styrene, In the case of a solventless adhesive such as epoxy, the film forming adhesive layer 2 is formed by semi-curing. As such an adhesive, it is necessary to use an adhesive that does not dissolve in the synthetic resin liquid 3 applied on the film-forming adhesive layer 2.

Next, 200 to 3 are formed on the film-forming adhesive layer 2.
A synthetic resin liquid layer 3 is formed by applying a desired amount of an addition polymerization type synthetic resin liquid typified by an unsaturated polyester resin having a viscosity of 0,000 cps, and then a wood veneer 4 is laminated on the synthetic resin liquid layer 3. To do. Wood veneer 4 is oak, oak,
Tree species such as birch, sen, and duck, which are sufficiently dried, are not suitable for the veneer that is too thick to allow the synthetic resin solution to penetrate from the bottom side to the inside. From the standpoint of production, it is preferable to use those having a thickness within the range of 0.3 to 1.5 mm.

The thickness of the synthetic resin liquid layer 3 applied varies depending on the tree species and the thickness of the wood veneer 4, but is generally sufficient if it is sufficiently impregnated into the wood veneer 4. The applied resin liquid needs to have a certain range of viscosity. That is, it is necessary to keep a sufficient amount on the wooden substrate 1 after coating, without flowing, and from this point, high viscosity is more convenient. On the other hand, it is preferable that the resin liquid has a low viscosity from the viewpoint of impregnation into the wood veneer 4, and it is more effective from the viewpoint of suppressing the outflow from the wood veneer 4 after impregnation. Further, since the resin liquid impregnated in the wood veneer 4 flows so as to be extruded from the wood veneer 4 by the air or the gasification component, it is required to quickly gel.

To satisfy these conditions, the viscosity of the resin liquid is required to be 200 cps or more. If it is less than 200 cps, even if the required amount is applied onto the wood veneer 4, it will not flow out and be retained.
On the other hand, those with a viscosity of 30,000 cps or more have a high viscosity, which makes automatic coating with a roll coater or the like difficult, so 30,000 cps or less is preferable for continuous and efficient production. Although these resin liquids are impregnated into the wood veneer 4 in a state where the resin liquid is heated and reduced in viscosity, a low viscosity is preferable at the time of impregnation,
Hot pressing temperature, ie 100 cp within 100-140 ° C
The following shall be used. The pressing force at this time is 5
15Kg / cm ² is required.

That is, since the resin liquid having a viscosity of 100 cps or more when hot pressed requires a long time to impregnate the wood veneer 4, the pressing time becomes long and the productivity is greatly reduced. If the applied pressure at the time of hot pressing is low, the viscosity is lowered, and it tends to flow out to the side surface, and it is not possible to obtain a decorative plate uniformly impregnated with the resin liquid. If the applied pressure exceeds 15 kg / cm ² , the structure of the wood veneer 4 may be destroyed. Next, the hardening reaction of the impregnated resin liquid starts and gelation proceeds, but if the gelation is started at a low temperature, the resin liquid can be prevented from flowing out from the wood veneer 4. From this, it is desirable that the kick-off temperature of the initiator added to the resin liquid be 100 ° C. or lower.

As an initiator to be added to the synthetic resin liquid in order to accelerate the curing of the synthetic resin liquid, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, caprylyl peroxide, lauroyl peroxide, acetyl peroxide are used. The kick-off temperature of oxides is 50 ℃
Organic peroxides in the 100 ° C range are used. When an initiator with a kick-off temperature of 100 ° C or higher is added, the curing temperature of the synthetic resin liquid increases and the curing reaction slows down, and the synthetic resin liquid once impregnated in the wooden veneer 4 is cured.
It is not preferable because it flows out from. If the kick-off temperature is 50 ° C. or lower, the pot life of the synthetic resin liquid will be shortened, and there is a risk of partial curing in the supply path of a pump or the like. There is nothing that cannot be used.

An accelerator may be added to the synthetic resin liquid together with the above-mentioned initiator. As such an accelerator, a cobalt accelerator, a vanadium accelerator, a manganese accelerator, etc. can be used.

Further, the synthetic resin liquid 3 is applied to the wood veneer 4 side in advance, and the synthetic resin liquid 3 is superposed on the film-forming adhesive layer 2 applied on the above-mentioned wooden substrate 1 so that the wood veneer is made. 4 may be laminated, and in this case, the work of applying the synthetic resin liquid 3 to the wood veneer 4 can be performed in parallel with the work of forming the film-forming adhesive layer 2 on the wooden substrate 1. It is also effective to apply the synthetic resin liquid 3 on the upper surface side of the wood veneer 4 when the wood veneer 4 is thick or when the wood grain is dense and the impregnation of the resin liquid is slow.

As described above, the wood veneer 4 is sequentially laminated on the wooden substrate 1 with the film-forming adhesive layer 2 and the synthetic resin liquid layer 3 containing the initiator, and is inserted into the hot press. Then, when the wood veneer 4 is heated and pressed at a predetermined temperature and pressure for an appropriate period of time, the synthetic resin liquid 3 is imparted with fluidity and at the same time a compressive action is exerted between the wood substrate 1 and the wood veneer 4. An attempt is made to penetrate into the opposing surfaces of the wood substrate 1 and the wood veneer 4.

At this time, since the film-forming adhesive layer 2 is interposed between the wooden substrate 1 and the synthetic resin liquid layer 3, the synthetic resin liquid permeates to the wooden substrate 1 side by the adhesive film forming layer 2. Therefore, the synthetic resin liquid 3 is impregnated into the wood veneer 4 from the lower surface of the wood veneer 4 which is in direct pressure contact.

As described above, when the synthetic resin liquid 3 enters the wood veneer 4 from the lower surface of the wood veneer 4 and rises, the synthetic resin liquid 3 exists in the cell voids of the wood veneer 4 correspondingly. The air escapes as it is pushed upwards and is discharged to the outside to easily impregnate the wood veneer with the synthetic resin liquid 3. At this time, if the heating temperature by the hot press is 100 ° C or lower, the synthetic resin liquid impregnated in the wood veneer 4 may be delayed in curing, and the resin liquid once impregnated may flow out. Since styrene is present as a monomer in the liquid, it boils and acts so as to push out the resin liquid, so that the wood veneer 4 has a portion where the synthetic resin liquid is not impregnated. It is necessary to adjust to the range of 140 ℃.

When the thickness of the film-forming adhesive layer 2 is 30 μm or less, the film layer becomes thin and the pressure of the press causes the synthetic resin liquid 3 to penetrate through the film layer to the wooden substrate 1 side. In order to effectively prevent the synthetic resin liquid 3 from being impregnated into the wooden substrate 1 side by the film-forming adhesive layer 2, it is preferable that the thickness thereof is set to 30 μm or more, because there is a risk of infiltration. Even if the surface thereof is rough, such as plywood, if it is formed to a thickness of about 100 μ, the prevention will be ensured and the wood veneer 4 can be impregnated with the synthetic resin liquid 3 more favorably.

Thus, when the hot press treatment by hot pressing is performed for a predetermined time, the resin liquid is made to flow and impregnated into the cell voids of the veneer, the temperature is further raised in the material, and the initiator acts. The curing reaction of the impregnated synthetic resin liquid is immediately and rapidly started to cure in the wood veneer, and at the same time, the film-forming adhesive layer 2 is activated by heating to exert an adhesive effect, and the wood veneer 4 is produced. A beautiful decorative board which is adhered to and integrated with the wooden substrate 1 via the film adhesive layer 2 and has no scratches or the like is obtained. Next, specific examples of the present invention will be shown.

Example 1 A plywood sheet having a thickness of 12 mm was used as a substrate, and 10 parts of polyvinyl alcohol and 5 parts of a pigment were added to a DAP prepolymer using acetone as a solvent, and an adhesive having a nonvolatile content of 70% was added to the substrate. Was applied by a roll coater at a rate of 110 g / m ² , and then the adhesive was applied by a warm air dryer to 80
It was dried at 5 ° C. for 5 minutes and air-cooled appropriately to form a film-formed thermosetting adhesive layer having a thickness of about 60 μm. On the other hand, the thickness is 1.0 mm
Unsaturated polyester resin liquid (viscosity 5000 cps / 25 ° C) containing 1 part by weight of BPO as an initiator is applied to one side of the dried dried veneer (water content 5%) at a rate of 500 g / m ² = Then, the resin layer is laminated on the substrate so as to be in contact with the film-forming adhesive layer, and a polyester film having a thickness of 20 μm is placed on the single plate as a release film and then hot-pressed. It was hot pressed for 5 minutes under the conditions of 120 ° C. and 10 kg / cm ² . By this heat and pressure treatment, a veneer was obtained in which the veneer was impregnated with the resin solution and cured, and the veneer was integrated with the substrate by the adhesive layer.

Example 2 In the above Example 1, instead of applying the synthetic resin solution to the single plate, the synthetic resin solution was applied on the film-forming adhesive layer provided on the upper surface of the substrate, and the synthetic resin solution was applied on the synthetic resin solution. After laminating veneer on
A hot pressing process was performed under the same conditions as above to obtain a resin-injected veneer-coated veneer.

Example 3 In Example 1 above, 1 part by weight of MEKPO and 0.2 part of an 8% solution of cobalt naphthenate were added to both sides of the veneer to obtain 250 g / unsaturated polyester resin solution having a viscosity of 300 cps. The veneer is applied at a ratio of m ^{2, and} the veneer is laminated on the film-forming adhesive layer on the substrate shown in Example 1 with a resin liquid layer on the lower surface side thereof and on the resin liquid layer on the upper surface side of the veneer. Place the release film on the hot press and apply a thin layer of metal soap to the hot press hot platen.
A resin-injected veneer-coated veneer was obtained by heat-pressing for 4 minutes under a condition of / cm ² . When the veneer surface of the veneer veneer obtained in each of these Examples was observed with a microscope, the resin injection rate into the cell voids such as conduits reached 90% or more.

Comparative Example Using the same substrate, single plate and adhesive as in Example 1 above,
Immediately after the adhesive is applied on the substrate, the veneers are laminated and integrally bonded, and then an unsaturated polyester resin liquid with a viscosity of 10 cps containing 1% BPO as an initiator is applied to the upper surface of the veneer. It was applied at a ratio of g / m ² =, and hot pressed under the same conditions by hot pressing. In this case, a considerable amount of resin liquid was flowing out at the time of pressing, and the remaining resin liquid was easily impregnated into the veneer.However, when the veneer surface of the obtained veneer was observed with a microscope, cells such as conduits The resin injection rate into the voids was only about 50%, and non-impregnated parts appeared unevenly on the surface.

[0026]

As described above, according to the method for manufacturing a decorative board of the present invention, after the adhesive is applied on the wooden substrate, the adhesive is heated to form a film, and then the film-forming adhesion is performed. A wood veneer is laid on the agent layer through a coating layer of an addition polymerization type synthetic resin solution of appropriate thickness having a viscosity of 200 to 30,000 cps, and heat and pressure treatment is performed within the range of 100 to 140 ° C. The wood veneer is impregnated with a synthetic resin liquid and hardened, and the wood veneer is adhered and integrated on a wood substrate.
Since the adhesive applied on the wooden substrate is formed into a film, when the wood veneer is laminated on this with a synthetic resin solution of an appropriate coating thickness and subjected to heat pressure treatment, the synthetic resin solution The film-forming adhesive layer can surely prevent the wood substrate side from being impregnated, and a large amount of the resin liquid can be impregnated into the wood veneer.

Furthermore, the viscosity of the synthetic resin liquid decreases upon heating, the fluidity increases and the wood veneer is easily impregnated, and the initiator added to the synthetic resin liquid has a kick-off temperature of 100. The temperature is below ℃, and the heating temperature is 100 to 140 ℃ in the heat and pressure treatment range. Therefore, after impregnation, the initiator does not start the reaction and the synthetic resin liquid does not flow out from the wood veneer. It is possible to obtain a synthetic resin-impregnated decorative plate that can be cured while being held in a single plate, and that has good cosmetic properties and is free from scratches and the like.

Further, the synthetic resin liquid having a kick-off temperature of 50 to 100 ° C. to which a thermal decomposition type initiator is added will not be cured even if a considerable time is required from the preparation of the resin to the heat and pressure treatment. However, it is only possible to exert fluidity when heated and pressed. Therefore, the work of applying the film-forming adhesive layer on the wooden substrate and the work of placing the wood veneer through the synthetic resin liquid containing the initiator. , A series of steps of hot pressing by a press can be continuously performed, productivity of decorative boards can be remarkably improved, and resin impregnation treatment having physical properties excellent in hardness, strength, cosmetic properties, etc. It is possible to efficiently and stably manufacture a plate-attached decorative plate.

[Brief description of drawings]

FIG. 1 is a simplified cross-sectional view showing a state where a wood veneer is laminated on a wooden substrate with a film-forming adhesive layer 2 synthetic resin liquid interposed therebetween.

[Explanation of symbols]

 1 Wood substrate 2 Film-forming adhesive layer 3 Synthetic resin liquid layer 4 Wood veneer

Claims (3)

[Claims] 1. After applying an adhesive on a wooden substrate, the adhesive is formed into a film by heating or other means, and then the film-forming adhesive layer has a viscosity of 200 to 30,000 cps.
The wood veneer is superposed through the coating layer of the addition polymerization type synthetic resin liquid of appropriate thickness so that the viscosity at the hot pressing temperature is 100 cps or less, and the resin is heated and pressurized within the range of 100 to 140 ℃. A method for manufacturing a decorative board, which comprises lowering the viscosity, impregnating a wood veneer with a synthetic resin solution, and curing the veneer to bond and integrate the wood veneer onto a wooden substrate. 2. The method for producing a decorative board according to claim 1, wherein after the wood veneer is placed, the surface of the wood veneer is coated with an addition polymerization type synthetic resin liquid. 3. The method for producing a decorative board according to claim 1, wherein the kick-off temperature of the initiator added to the addition polymerization type synthetic resin liquid is 100 ° C. or lower.