JP2005145077A - Decorative laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative laminate prevented from undergoing deformation due to moisture absorption/releasing under open air during storage or long term use, and easily processed with a fireproof, odorless and low priced adhesive like an emulsion adhesive on application. <P>SOLUTION: The laminate is composed by laminating a decorative sheet 2 on one side, and a chartaceous sheet 4 on the other side, of a ligneous substrate 3; wherein the chartaceous sheet 4 comprises two tissue papers 41 and 43 of a basis weight of 25 to 40 g/m<SP>2</SP>and being bonded through an extrusion coating layer 42 of a thermoplastic synthetic resin. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a decorative board that is used as a surface material for various furniture and building interior materials, etc., and does not warp due to the humidity and moisture of the outside air.

  Conventionally, the moisture content of plywood, MDF (medium density wood fiber board), hard board, particle board, etc., moisture content or water content is easily changed by moisture release, so-called wood-based substrate impregnated with thermosetting resin A decorative board is known in which a decorative coating layer is formed by laminating and fixing decorative sheets such as paper and thermoplastic resin sheets, and is used for various purposes such as decorative architectural boards and furniture surface decorative boards. However, the degree of drying of the adhesive when sticking the decorative sheet, and the influence of moisture during storage or long-term use may cause a malfunction. That is, when the moisture content of the wooden base material is smaller than the equilibrium moisture content of the wooden base material under the outside air condition, the decorative sheet of the decorative board is laminated and absorbs moisture or water from the non-adhered surface. If the moisture content of the wooden substrate is higher than the equilibrium moisture content of the wooden substrate under the outside air condition, the moisture tends to be released and contracted. On the other hand, since a decorative coating layer is generally applied to the surface side, moisture absorption / release from the surface side is hardly performed. Therefore, the expansion rate or contraction rate of the front surface side and the back surface side of the decorative board is different, causing warping as shown in FIG. 2, resulting in a loss of commercial value and difficulty in bonding in use. In addition, when processed into a flash-structured door, sliding door, partition, etc., there is a problem that the surface plate as shown in FIG. It was.

  In order to eliminate such disadvantages, as a method for preventing moisture change from the back side of the decorative board on the back side of the decorative board with a decorative sheet pasted on the surface, moisture content change of the wooden substrate due to moisture release, for example, paint There are known materials coated with synthetic resin films such as vinyl chloride, polyethylene and polypropylene, and materials laminated with two layers of paper and synthetic resin.

  However, it is difficult to form a uniform moisture-proof and waterproof layer in the case where the above-mentioned paint is applied, because the paint on the surface of the wood base material such as plywood or MDF is strongly sucked and the smoothness of the surface is poor. If there is a defect and the synthetic resin film such as vinyl chloride, polyethylene, polypropylene is laminated, the film cost is high, and furthermore, a solvent-type adhesive must be used for the lamination, so it is safe against fire, An emulsion type adhesive having no odor cannot be used and tends to be expensive in price. In the case of a sheet composed of two layers of paper and synthetic resin, there are problems such as the sheet being easily curled and difficult to affix to a wooden base material.

  The present invention has been made in view of such problems, and the object of the present invention is to prevent plate warping due to moisture absorption, moisture release, etc. due to outside air during storage or long-term use. At the same time, it is an object to provide a decorative board that is safe against fire such as an emulsion type adhesive, has no odor, and can be easily processed with an inexpensive adhesive.

In order to achieve the above object, the decorative board of the present invention has a decorative sheet laminated on one side of a wooden base material, and two sheets of thin paper having a weight of 25 to 40 g / m ² are thermoplastic on the other side. It is characterized in that paper-based sheets that are bonded through a synthetic resin extrusion coating layer are laminated.

  And it is more preferable that the extrusion coating layer of the thermoplastic synthetic resin is a polyolefin resin.

  The decorative board of the present invention has a constitution in which a paper-based sheet obtained by adhering two thin paper sheets to the back surface of the decorative plywood through an extrusion coating layer of a thermoplastic synthetic resin is bonded as a moisture-proof layer. Since moisture and humidity from the back surface are blocked by the thermoplastic synthetic resin layer, warpage is prevented from occurring.

  In addition, the moisture-proof layer attached to the back surface of the decorative board has a three-layer structure in which a thermoplastic synthetic resin layer is used as a core layer and thin papers are laminated and integrated on the front and back. Therefore, the thermoplastic synthetic resin layer of the core layer In addition to the moisture-proofing effect, the thin paper on the front and back sides is good for the back side of the decorative board and the post-processed surface by using an emulsion-type adhesive that is safe against fire, has no odor, and is inexpensive. Demonstrate adhesive strength. Furthermore, the decorative plate can be easily pasted onto flash doors, sliding doors, partitions, etc., and a stable product can be obtained.

  Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a laminated structure of a decorative board according to the present invention, wherein 1 is a decorative board, 2 is a decorative sheet, 3 is a wood-based substrate, 4 is a paper-based sheet, 41 and 43 are thin papers, and 42 is heat. Plastic synthetic resin layers and 5 represent adhesive layers, respectively.

  As can be seen from these drawings, the decorative board 1 has a configuration in which a sheet-like sheet 4 in which two thin paper sheets 41 and 43 are bonded via an extruded coat layer 42 of a thermoplastic synthetic resin as shown in FIG. The adhesive layer 5, the woody base material 3, the adhesive layer 5, and the decorative sheet 2 are laminated in order from the bottom. A feature of the decorative board 1 of the present invention is that a paper sheet 4 formed by adhering two thin paper sheets 41 and 43 through a thermoplastic synthetic resin extrusion coating layer 42 is adhered to the back surface of the decorative board 1 as a moisture-proof layer. It exists in providing through the agent layer 5.

The thin papers 41 and 43 used for the paper-based sheet 4 acting as a moisture-proof layer of the wood-based decorative board are interlayer paper strengths by mixing a printed paper for building materials having a weight of 25 to 40 g / m ² , pure white paper, or synthetic resin. A thin paper (so-called reinforced printing paper) reinforced with a thickness of 25 to 35 g / m ² is suitable. Of course, the other thin paper to be laminated may be the same or different.

  The thermoplastic synthetic resin layer 42 for bonding the two thin papers 41 and 43 constituting the paper-based sheet 4 only needs to have water resistance so that the wood-based base material does not warp as a result. Other than resin, it can be used in principle. Preferable examples include polyolefin resins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer. The thickness of the thermoplastic synthetic resin layer 42 is about 1 to 50 μm.

  To make a paper-based sheet 4, a method of laminating thin paper 41, 43 and a thermoplastic synthetic resin 42 with adhesive or using heat without using an adhesive, extrusion lamination to two thin papers 41, 43 There is a method of laminating a layer of the thermoplastic synthetic resin 42 by melt extrusion at the same time, and a laminating method is selected according to the kind of the thermoplastic synthetic resin 42. When the three layers of the thin paper 41, the thermoplastic synthetic resin 42 and the thin paper 43 are formed as in the present invention, the number of steps can be reduced by laminating the three layers at once by the extrusion laminating method. When using polyolefin-based resins such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer as thermoplastic synthetic resins, the method of laminating the thermoplastic synthetic resin simultaneously with melt extrusion by the extrusion laminating method is suitable. Is the method.

  A typical example of the wood-based substrate 3 is plywood, but if it is difficult for moisture to permeate, the problem is solved by adopting a similar structure. In addition to plywood, examples include wood bark, laminated timber, particle board, MDF, hard board, and other various fiber boards.

Common adhesives such as vinyl acetate resin, ethylene / vinyl acetate resin, urea resin, urethane resin, etc., are used for affixing the paper-based sheet 4 and the wood-based substrate 3 to the fire. It is preferably used because it is safe, odorless and inexpensive.

  By using such a three-layer structure, moisture absorption / release to the back surface layer of the woody base material 3 is prevented by the thermoplastic synthetic resin layer 42 of the core layer, and the thermoplastic synthetic resin layer 42 Since the thin papers 41 and 43 are present on the front and back surfaces, the adhesive strength of the adhesive to the back surface of the wood-based substrate 3 is improved, so that it can be easily attached with a general laminator device. Moreover, sufficient adhesive strength with the ground surface can be obtained by applying the adhesive to the ground surface.

  As described above, in the present invention, since both surfaces of the paper-based sheet that acts as a moisture-proof layer are composed of thin paper, an inexpensive and safe emulsion-type adhesive is used for bonding to a wooden substrate or construction surface. And can be easily stacked.

  Examples of the present invention will be described below.

[Example 1]
A polyethylene film is extruded and coated to a thickness of 20 μm from a T-die extruder on a 30 g / m ² inter-paper reinforced paper, and another sheet of paper and a 30 g / m ² inter-paper reinforced paper are laminated at the same time, and a chill roll Was cooled to prepare a paper-based sheet comprising two layers of thin paper. Next, a decorative plywood was prepared by bonding a vinyl chloride adhesive sheet with a vinyl chloride adhesive at an adhesive application amount of 80 g / m ² to a 2.0 mm thick plywood. Next, a decorative plywood having a moisture-proof layer was obtained by laminating the paper-based sheet obtained above on the back surface of the decorative plywood using an emulsion-type vinyl acetate adhesive. Next, the decorative plywood having the above moisture-proof layer was left to stand for one week in an atmosphere at a temperature of 25 ° C. and a humidity of 70%, and no abnormality was found.

[Comparative Example 1]
In the above example, without attaching a paper-based base material to the back surface of the decorative plywood laminated with the vinyl chloride decorative sheet, the sample was left to stand for 1 week in an atmosphere at a temperature of 25 ° C. and a humidity of 70%. Apparently, a convex warp of 30 mm or more occurred, and it became an impractical decorative plywood.

It is sectional drawing which shows the laminated structure of the decorative board of this invention. It is a perspective view of a conventional product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Decorative board 2 Decorative sheet 3 Woody base material 4 Paper-based sheet 41, 43 Thin paper 42 Thermoplastic synthetic resin layer 5 Adhesive layer

Claims (2)

A paper-based system in which a decorative sheet is laminated on one surface of a wood-based substrate, and two thin papers weighing 25 to 40 g / m ² are bonded to the other surface via an extruded coating layer of a thermoplastic synthetic resin. A decorative board in which sheets are laminated. The decorative board according to claim 1, wherein the extrusion coating layer of the thermoplastic synthetic resin is a polyolefin resin.

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