JP2000190425A - Decorative panel and flash panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative panel not generating a panel warpage phenomenon caused by the absorption and discharge of moisture due to the open air during keeping or at the time of longterm use and capable of using a method good in productivity like a high frequency heating method in the adhesion of a core material and a frame material and a flash panel produced by using the decorative panel. SOLUTION: In a decorative panel 1 constituted by laminating a decorative sheet 2 on one surface of a wooden substrate and laminating a moistureproof sheet, which is formed by bonding two paper layers 41, 42 through an extruded coating layer of a thermoplastic synthetic resin, on the other surface thereof, the paper layer positioned on the side of the wooden substrate among the paper layers 41, 42 has wax picking strength of 18 or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative board which is used as a surface material for various kinds of furniture and building interior materials and which does not warp due to humidity or moisture of the outside air.

[0002]

2. Description of the Related Art Conventionally, plywood, MDF (medium density fiberboard),
Moisture or water absorption of hard board, particle board, etc.
Alternatively, a decorative sheet such as a thermosetting resin-impregnated paper or a thermoplastic resin sheet is laminated and fixed on one surface of a so-called wood-based base material, the moisture content of which is easily changed by moisture release, and a decorative coating layer is formed. Decorative boards are often used and used for various purposes such as decorative architectural boards, furniture surface decorative boards, etc. May be affected by moisture when used. That is, when the water content of the wood-based substrate is smaller than the equilibrium water content of the wood-based substrate under the open air condition, the decorative sheet of the decorative board is laminated and moisture is absorbed or absorbed from the surface that is not fixed. On the other hand, when the water content of the wood-based material is larger than the equilibrium water content of the wood-based material under the open air condition, the water-based material tends to expand and contract. On the other hand, there is almost no moisture absorption and desorption from the surface side since a decorative coating layer is generally applied to the surface side. Therefore, there is a problem that the expansion rate or the shrinkage rate of the front side and the back side of the decorative board are different, and the wooden base material is warped.

As a method of preventing such a warp of a wooden base material, the present applicant has proposed a moisture-proof sheet having a structure in which a thermoplastic synthetic resin layer is sandwiched between paper layers. Affixing to the back surface was proposed in Japanese Patent Application No. 7-206644. By doing so, a wood-based decorative board without warping or distortion was obtained even under use conditions or storage conditions under adverse conditions, but as a post-process, when processing into interior doors, sliding doors, partitions, etc., decorative boards As a method of bonding with the frame material and the core material, an adhesive is applied to both or one of the opposing adhesive surfaces, the opposing adhesive surfaces are pressed together and heated, but as a heating method at this time, By placing a clamp on the adhered wood and placing it in a heated air atmosphere in a pressed state, or by sandwiching the adhered wood between metal hot plates and heating by bringing the metal forming the hot plate into contact with the wood. , And the adhesive was cured. However, all of these bonding methods have low heating efficiency and low thermal conductivity of the wood itself, so that it takes a long time to heat the inside of the wood, and uneven heating occurs on the surface and inside of the wood. And there is a problem in terms of productivity and quality.

As a method for solving the above problems, a bonding method using high-frequency heating has been proposed. By using this bonding method, the heating efficiency is improved, the heating time is shortened, the heating unevenness does not occur, and the productivity is greatly improved, but the heating method is different from heat conduction,
Due to internal heat generated by high frequency, heating is uniform, and the temperature rises quickly, so the curing temperature of the adhesive rises, and the polyolefin resin, the moisture-proof layer of the moisture-proof sheet, is melted once and restored to its original state by cooling again I do. However, this causes a new problem that the interface between the paper layer and the polyolefin resin layer is deteriorated, the adhesive strength is reduced, and the possibility of peeling is generated.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a plate for absorbing moisture or releasing moisture during storage or during long-term use. Does not cause warping,
An object of the present invention is to provide a decorative plate that can use a method with good productivity such as a high-frequency heating method for bonding with a frame material, and a flash panel manufactured using the decorative plate.

[0006]

In order to achieve the above object, a decorative sheet is laminated on one surface of a wooden base material, and two paper layers are formed on the other surface by an extrusion coat layer of a thermoplastic synthetic resin. A decorative sheet comprising a moisture-proof sheet laminated through a laminate, wherein at least the paper layer of the paper layer located on the side of the wooden substrate has a wax picking strength of 18 or less. Is what you do. With this configuration, a decrease in interlayer adhesion of the moisture-proof sheet due to the effect of high temperature during high-frequency heating is prevented. It is a plate and can be manufactured by a high-frequency heating method with good productivity as a means of post-processing. In addition, since both surfaces of the moisture-proof layer are covered with the paper layer, the paper layer absorbs the adhesive well, so that it can be easily attached to a wooden base material and adhered to a door core material or another base material.

[0007] A decorative sheet is laminated on one side of a wooden base material, and two paper layers are adhered to the other side via an extrusion coat layer of a thermoplastic synthetic resin. A decorative board formed by laminating a moisture-proof sheet having a wax picking strength of 18 or less on the paper layer located on the material side is bonded to at least the front and back surfaces of a wooden frame material with the moisture-proof sheet side of the decorative board being the frame material side. A flash panel characterized by being bonded by high frequency heating via an agent. By doing so, the thermoplastic synthetic resin melted by the high-frequency heating method is cooled in a state of being infiltrated into the paper layer, so that the anchoring effect prevents a decrease in adhesive strength, so that the movement of moisture and moisture between the decorative boards and Moisture and moisture transfer between the decorative panel and the outside air is prevented, so that even if there is a temperature difference or humidity difference between the outside air on the front and back of the flash panel, there is little warpage, and the wooden frame A high-frequency heating method with good productivity can be used as a means for sticking to a material and a flash panel member, and a flash panel with excellent quality can be easily and inexpensively provided.

[0008]

Embodiments will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a laminated structure of a decorative panel of the present invention, and FIG. 2 is a partially cutaway side view of a flash panel manufactured using the decorative panel of the present invention.
2 is a decorative sheet, 3 is a wooden base material, 4 is a moisture-proof sheet, 4
Reference numerals 1 and 42 denote paper layers, 43 denotes a thermoplastic synthetic resin layer, 5 denotes an adhesive layer, 6 denotes a flash panel, 7 denotes a frame material, and 8 denotes a core material.

As shown in FIG. 1, the decorative board 1 of the present invention has a decorative sheet 2 laminated on a surface of a wooden base material 3 with an adhesive layer 5 interposed therebetween, and an adhesive layer 5 on the back surface. And a moisture-proof sheet 4 in which two paper layers 41 and 42 are adhered via an extrusion coat layer 43 of a thermoplastic synthetic resin. A feature of the decorative board 1 of the present invention is that the two paper layers 41 and 42 constituting the moisture-proof sheet 4 are made of a paper-based sheet having a wax picking of 18 or less.

[0010] The decorative sheet 2 is not limited to a specific material or structure, and a single layer or a laminated structure of an arbitrary material can be selected according to the application. Here, in consideration of good ink adhesion, ease of molding, and high moisture resistance, a pattern is printed with ink on the surface of a thermoplastic resin film such as polyvinyl chloride, polyethylene, acrylic, polyester, etc. Is used.

The wood-based substrate 3 has the same structure as that described above, as long as moisture or moisture can penetrate into the substrate, such as plywood, MDF, hard board, or particle board, to cause an irregular warp or the like. This solves the problem, and can be an object of the present invention as the wooden base material 3.

The moisture-proof sheet 4 acting as a moisture-proof layer of the decorative board 1 of the present invention is made of a thermoplastic synthetic resin layer 4 having moisture-proof properties.
3 has a three-layer structure in which paper layers 41 and 42 are adhered to both surfaces.
The paper layers 41 and 42 used for the moisture-proof sheet 4 have a weight of 20 to 40 g / m ^{2 and} a wax picking strength of 18.
The following paper-based sheets are favorably used. The test method for the wax picking strength is specified in JIS-P8129 in detail. That is, a series of numbered waxes with sequentially increasing adhesiveness is fused to the paper surface, allowed to cool, peeled off from the paper surface, and the highest wax number that does not damage the paper surface is assigned to the paper surface strength. It is assumed that. Paper-based sheets exceeding a wax picking strength of 18 are generally classified as inter-sheet reinforced paper,
A large amount of thermoplastic resin such as acrylamide resin is mixed at the time of papermaking in order to make the paper layer strength sufficient, and the paper layer is strengthened.The surface of the paper layer also becomes dense,
Since the thermoplastic synthetic resin 43 melted by the high-frequency heating is cooled in a state where it hardly penetrates between the pulp fibers of the paper layers 41 and 42, it is difficult to obtain the anchoring effect and the paper layer 4
Adhesion at the interface between the thermoplastic resin layers 1 and 42 and the thermoplastic synthetic resin layer 43 is deteriorated, and peeling is likely to occur. On the other hand, untreated pure white paper to which no thermoplastic resin such as acrylamide resin is added at the time of paper making, or print paper having a wax picking strength of 18 or less such as print paper obtained by mixing a small amount of thermoplastic resin such as acrylamide resin at the time of paper making, The plastic synthetic resin 43 is a paper layer 4
1 and 42, and the anchoring effect prevents a decrease in the adhesive strength, so that the thermoplastic synthetic resin layer 43 and the paper layer 41,
The adhesive strength is maintained without peeling between the 42 layers. However, when the wax picking strength is about 12 or less, the surface strength of the paper is inferior, there is a possibility that delamination such as paper scum may occur, and the adhesive strength may be easily varied.

As the thermoplastic synthetic resin layer 43 having moisture proof properties, it is sufficient that the wooden base material has a water resistance such that it does not warp, and in principle other than water-soluble resins can be used.
Preferred examples include polyolefin resins such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer, which form a moisture-proof layer having a moisture permeability of 30 g / m ² · 24 hr or less, preferably a moisture permeability of 15 g / m ² · 24 hr or less. Preferably, the thickness of the thermoplastic synthetic resin layer 43 is preferably about 15 to 50 μm.

To make the moisture-proof sheet 4, paper layers 41, 42
And using a film of thermoplastic synthetic resin 43 with an adhesive,
Or a method of bonding without using heat, etc., two paper layers 4
For example, there is a method in which a layer of the thermoplastic synthetic resin 43 is melt-extruded and laminated simultaneously by an extrusion laminating method into the layers 1 and 42. As in the present invention, the paper layer 41, the thermoplastic synthetic resin 43 and the When forming two layers, three at a time by the extrusion lamination method
Laminating two layers is an optimal method as it requires fewer steps. Examples of the thermoplastic synthetic resin to be used include polyethylene, polypropylene, and polyolefin resins such as ethylene-vinyl acetate copolymer, etc., but polyethylene resins are suitable from the viewpoint of processability, cost, and the like.

The adhesive layer 5 used for attaching the moisture-proof sheet 4 to the wood-based substrate 3 is a common adhesive, for example, vinyl acetate resin, ethylene / vinyl acetate resin, urea resin, urethane resin. An emulsion type adhesive such as a system is preferably used because it is safe against fire, has no odor, and is inexpensive.

By using the three-layer structure of the decorative board 1 of the present invention, absorption and release of moisture to and from the back layer of the wooden base material 3 are prevented by the thermoplastic synthetic resin layer 43 as the core layer. In addition, since the paper layers 41 and 42 are present on the front and back surfaces of the thermoplastic synthetic resin layer 43, the adhesive strength to the back surface of the wooden base material 3 by the adhesive is improved. Can be stuck on.

Also, here, the embodiment in which the wax picking strength is 18 or less is used for both of the paper layers 41 and 42 located on both surfaces of the 43, but the adhesive force is reduced by high frequency processing. The reason for the decrease is that the adhesive side that adheres to the wooden base material is more likely to be heated, and only one of them may have a wax picking strength of 18 or less.

As shown in FIG. 2, a flash panel 6 manufactured using the decorative board 1 of the present invention is provided on both sides of a flash panel member having a wood frame member 7 and a honeycomb panel or the like as a core member 8. With the moisture-proof sheet 4 of the decorative board 1 made of the wooden base material 3 facing inside, using an emulsion-type adhesive 9 such as vinyl acetate, acrylic, or rubber, it is press-bonded in a short time by high-frequency heating, This is a flash panel 6 that has been warped.

The bonding of members by high-frequency heating used in the present invention is such that when a high-frequency voltage is applied to the bonding surface of a processed material such as a decorative plate, a frame material, a core material, the material constituting the processed material and the adhesive violently rotates and vibrates. Heat is generated from the inside of the work material and the adhesive due to the friction between the molecules caused by this, instantly curing the adhesive and performing strong adhesion, fundamentally different from external heating, decorative board, Since the processing material itself such as the frame material and the core material generates heat, it has good thermal efficiency, greatly contributing to labor saving and improving productivity. Since uniform heating can be achieved, uniform bonding can be achieved.

[0020]

EXAMPLES Example 1 1.0% by weight of acrylamide resin weighing 23 g / m ²
A polyethylene film is extruded and coated to a thickness of 20 μm from a T-die extruder on a mixed printing paper for building materials (Satsuki 23, manufactured by Sanko Paper Co., Ltd.) having a wax picking strength of 16, and another weighing of 23 g / m ²
Was laminated (Satsuki 23, manufactured by Sanko Paper Co., Ltd.) and cooled with a chill roll to produce a moisture-proof sheet having a two-layer paper layer structure. Then, 3.0 mm thick M
An MDF decorative sheet was prepared by laminating a vinyl chloride decorative sheet having a thickness of 80 μm to a DF with a vinyl acetate adhesive. Next, the MDF decorative sheet having a moisture-proof layer was obtained by laminating the moisture-proof sheet obtained above on the back surface of the MDF decorative sheet using an emulsion-type vinyl acetate-based adhesive.

Comparative Example 1 In place of the above-mentioned printing paper for construction material (Satsuki 23, manufactured by Sanko Paper Co., Ltd.) prepared by mixing 1.0% by weight of an acrylamide resin having a weight of 23 g / m ² in the above example, a weight of 28 g / m 2 was used.
^2. Pure white paper for building materials having a wax picking strength of 11 without addition of acrylamide resin (manufactured by Sanko Paper Co., Ltd., SN
Except that P28) was used, an MDF decorative board was obtained in the same manner as in Example 1.

Comparative Example 2 In place of the above-mentioned printing paper for construction material (Satsuki 23, manufactured by Sanko Paper Co., Ltd.) in which 1.0% by weight of acrylamide resin having a weight of 23 g / m ² was mixed in the above example, a weight of 23 g / m ² was used.
^A MDF decorative board was prepared in the same manner as in Example 1 except that a reinforced paper between building materials having a wax picking strength of 20 mixed with 5.0% by weight of acrylamide resin of No. 2 (FIX23, manufactured by Sanko Paper Co., Ltd.) was used. Obtained.

The MDF decorative sheet prepared in Example 1 and Comparative Examples 1 and 2 was subjected to a high-frequency instantaneous flash press (YBF-255-W type, manufactured by Yamamoto Vinita Co., Ltd.).
It adhered to the flash door frame material under the following high frequency heating conditions. High-frequency heating conditions: voltage 200V, current 40KVA, frequency 13.56MH
A high frequency of _Z was applied for 15 seconds. Adhesion Test Based on the JAS plane tensile test method, an adhesion test is performed on each of the samples, and the state at the time of peeling is observed. The peel strength was 4 kg / cm ² or more. Table 1 shows the results.

[0024]

[Table 1] As is clear from the above results, 2 used for the moisture-proof sheet
A sheet using a paper-based sheet having a wax picking strength of 16 for the paper layers shows excellent results even when high-frequency heating bonding is performed.

[0025]

The decorative board of the present invention has a structure in which two paper layers are adhered to the back surface of a wooden base material through a thermoplastic synthetic resin extrusion coat layer, and a moisture-proof sheet is bonded to the back side. Since moisture and moisture from the back of the decorative board are blocked by the thermoplastic synthetic resin layer, the occurrence of warpage is prevented,
Further, the moisture-proof sheet adhered to the back of the decorative board has a three-layer structure in which a thermoplastic synthetic resin layer is used as a core layer and paper layers are integrally laminated on the front and back thereof. In addition to the moisture-proofing effect of the layer, the paper layer on the front and back sides uses an emulsion-type adhesive that is safe against fire, has no odor, and is inexpensive, on the back side of the decorative board and the post-processing surface. At the same time as exhibiting good adhesive strength, in order to make the paper layer into a paper-based sheet having a wax picking strength of 18 or less, the work of attaching a flash structure door, sliding door, partition, etc. can be easily performed at high speed by a high frequency heating method. As a result, a product having a stable quality can be obtained, and the use of a decorative board having a wooden board as a substrate can be further expanded.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a laminated structure of a decorative board according to the present invention.

FIG. 2 is a partially cutaway side view of a flash panel manufactured using the decorative board of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Decorative board 2 Decorative sheet 3 Wooden base material 4 Moisture-proof sheet 41, 42 Paper layer 43 Thermoplastic synthetic resin layer 5 Adhesive layer 6 Flash panel 7 Frame material 8 Core material 9 Adhesive layer

Continued on the front page F term (reference) 4F100 AK01D AK04 AK15 AK22H AK26 AP00A AP03 AR00B BA05 BA07 BA10B BA10E BA13 CB01 CB03 DB17 DG10C DG10E EH17D EH23 GB08 GB81 HB00B JB16D JD04D JK06JK20 J00L

Claims (2)

[Claims] 1. A moisture-proof sheet formed by laminating a decorative sheet on one side of a wooden base material and bonding two paper layers to the other side via an extrusion coat layer of a thermoplastic synthetic resin. In the decorative board, the paper layer located at least on the wooden base material side of the paper layer has a wax picking strength of 18.
A decorative plate characterized by the following. 2. A decorative sheet is laminated on one side of a wooden base material, and two paper layers are adhered to the other side via an extrusion coat layer of a thermoplastic synthetic resin. A decorative board formed by laminating a moisture-proof sheet having a wax picking strength of 18 or less on the paper layer located on the base material side is provided on at least the front and back surfaces of a wooden frame material, and the moisture-proof sheet side of the decorative board is placed on the frame material side A flash panel which is bonded by high frequency heating via an adhesive.