JP2005046342A - Top board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a top board having good surface physical properties such as a scratch resistance, a wear resistance and a pollution resistance, and a collapse resistance and a chemical resistance while taking into consideration environmental problems during incineration. <P>SOLUTION: The top board is made by laminating a cover sheet 12 made of a synthetic resin to the surface of a base board 11. The cover sheet 12 is made by laminating a reinforcing layer 13 made of a synthetic resin whose yield point load is 9 kgf or higher, tensile modulus is 50 kgf/mm<SP>2</SP>or higher, yield elongation is 3 to 8% to the base board, and laminating a decorative layer 12 in which a base material sheet 15 made of a polyolefin thermoplastic resin is decorated and a surface protective layer 17 made of an ionizing radiation setting resin set is formed on the surface thereof to the reinforcing layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a top plate used for furniture such as a desk or a table, or a bay window counter.

  In general, this type of top plate is required to have scratch resistance, depression resistance, contamination resistance, and the like. For this reason, for example, a decorative material such as that shown in FIG. 1 is used as a covering sheet by being laminated on a top board. As shown in the figure, the covering sheet 1 uses phenol resin-impregnated paper for the core paper 2, the printed paper 3 and the overlay paper 4 are overlapped on the front side, and the balance paper 5 is overlapped on the back side, and this is press-molded. It is manufactured by laminating and integrating. Among these, as the printing paper 2, the one on which the surface of the titanium paper 3a is printed with the ink 3b and further impregnated with the melamine resin liquid is used.

  Then, as shown in FIGS. 2 (A) and 2 (B), a top plate substrate 6 is prepared in which the corner portion of the boundary between the top surface and the side surface surrounding the top surface is curved or chamfered, The covering sheet 1 is bonded to the substrate 6 via an adhesive 7. At the time of laminating and bonding, a portion that contacts the curved surface of the peripheral portion is heated and softened with an infrared heater H or the like and pressed with a roller R so as to correspond to the shape of the peripheral portion. This is called post-form processing. Thus, the melamine resin decorative board which laminated | stacked and integrated the coating sheet 1 is integrated in the desk or table as a top plate.

  The above-mentioned top board has a problem that the melamine resin decorative board used emits formaldehyde. In addition, when the melamine resin decorative board is incinerated at the time of disposal, harmful gas is generated. Even when the substrate is a steel plate, there is a problem in that harmful gas is generated when it is introduced into a blast furnace in order to reuse the steel.

  Therefore, an attempt has been made to employ a decorative board in which a polyolefin resin sheet is stuck and laminated instead of a melamine resin decorative board as a top board. Since the polyolefin resin only generates water and carbon dioxide even when incinerated, the problem of harmful gases is solved. However, the decorative board on which the polyolefin resin sheet is laminated is inferior to the melamine resin decorative board in terms of indentation, scratch resistance, stain resistance, chemical resistance, etc., and these are insufficient in practical use. .

  The present invention has been made in view of such problems, and its purpose is to take into account environmental issues such as incineration and disposal such as scratch resistance, wear resistance, and contamination resistance. An object of the present invention is to provide a top plate that is excellent in surface physical properties and excellent in anti-sag and chemical resistance.

In order to achieve the above object, the top plate of the present invention is a top plate in which a covering sheet made of synthetic resin is bonded to the surface of the substrate, and the covering sheet has a yield point load of 9 kgf in order from the side closer to the substrate. The surface of the reinforcing layer made of a synthetic resin having a tensile elastic modulus of 50 kgf / mm ² or more and the yield elongation of 3 to 8% and the base sheet made of a polyolefin-based thermoplastic resin after being decorated And a decorative layer on which a surface protective layer made of a cured product of an ionizing radiation curable resin is formed.

  The substrate has a top surface portion, a side surface surrounding the periphery of the top surface portion, and a corner portion at the boundary between the top surface portion and the side surface portion, and the covering sheet is at least from the top surface portion of the substrate. It is preferable to use a material coated on the side surface portion via the corner portion.

  The top plate of the present invention is environmentally friendly, has various physical properties required for the top plate, such as scratch resistance, wear resistance, and contamination resistance, and is particularly excellent in resistance to depression and chemical resistance.

  FIG. 3 is a sectional view showing an example of a top plate according to the present invention, and FIG. 4 is a partially enlarged view of FIG.

As shown in FIGS. 3 and 4, the top plate P is obtained by laminating a covering sheet 12 on the surface of the substrate 11, and the covering sheet 12 is configured by laminating a reinforcing layer 13 and a decorative layer 14. . The reinforcing layer 13 of the covering sheet 12 is made of a synthetic resin having a yield point load of 9 kgf or more, a tensile elastic modulus of 50 kgf / mm ² or more, and a yield elongation of 3 to 8%. Further, the decorative layer 14 of the covering sheet 12 is made of a cured product of ionizing radiation curable resin on the surface thereof after decorating the base sheet 15 made of a polyolefin-based thermoplastic resin with a pattern ink 16 or the like. A surface protective layer 17 is provided.

Reinforcing layer 13 of the cover sheet 12, a tensile modulus of cracks in the reinforcing layer itself is generated by the impact when less than 50 kgf / mm ^2. Further, when the yield point load is less than 9 kgf, the dent of the covering sheet 12 is conspicuous due to the impact, and when the yield point load is 9 kgf or more, more preferably 12 kgf or more, the dent becomes less conspicuous. Further, if the yield elongation is less than 3%, cracks occur in the reinforcing layer 13 due to impact, and if it exceeds 8%, the deformation due to the impact is large, and cracks in the decorative layer 14 laminated on the reinforcing layer 13 are prominent. Therefore, a more preferable upper limit of the yield elongation is 5% or less.

The resin for forming a reinforcing layer 13 of the cover sheet 12, the yield point load than 9 kgf, the tensile modulus of 50 kgf / mm ² or more, and if the yield elongation at 3-8%, in particular its type, thickness For example, polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (for example, polyethylene terephthalate obtained by substituting a part of ethylene glycol with 1,4-cyclohexanedimethanol or diethylene glycol, etc.) -G (manufactured by Eastman Chemical Company)), polyethylene naphthalate, polybutylene terephthalate, terephthalic acid-isophthalic acid-ethylene glycol copolymer, polyester-based thermoplastic elastomer, polyester-based resins such as polycarbonate, and the like. . These resins may be used alone or as a mixture, and the reinforcing layer 13 composed of these resins may be a single layer or multiple layers. These polyester resins are uniaxially or biaxially stretched unstretched or at an appropriate magnification as required.

  The base material sheet 15 of the decorative layer 14 is made of a polyolefin-based thermoplastic resin as described above. The thickness is generally 20 to 300 μm. Moreover, this base material sheet 15 may be colored by adding a pigment or the like, if necessary, or may be subjected to easy adhesion treatment such as corona discharge treatment, plasma treatment, ozone treatment and the like. As the polyolefin-based thermoplastic resin, polyethylene, polypropylene, polybutene, polymethylpentene, olefin-based thermoplastic elastomer, or the like is used.

  The decoration process applied to the base material sheet 15 of the decorative layer 14 is generally decorated with the pattern ink 16, but is not particularly limited to this. Vapor deposition or a combination of these two or more decoration treatments may be used.

  The surface protective layer 17 of the covering sheet 12 is provided for imparting surface physical properties such as scratch resistance, abrasion resistance, and contamination resistance required for the top plate. As described above, the ionizing radiation curable type is used. Consists of cured resin.

  An ionizing radiation curable resin is a resin that undergoes a cross-linking polymerization reaction upon irradiation with ionizing radiation and changes to a three-dimensional polymer structure. Ionizing radiation means an electromagnetic wave or charged particle beam having an energy quantum capable of polymerizing and crosslinking molecules, such as visible light, ultraviolet light (near ultraviolet light, vacuum ultraviolet light, etc.), X-ray, electron beam, ion beam, etc. There is. Usually, ultraviolet rays or electron beams are used. As the ultraviolet light source, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, or a metal halide lamp can be used. As the wavelength of the ultraviolet light, a wavelength range of 190 to 380 nm can be used. As the electron beam source, various electron beam accelerators such as a cockcroft-wald type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type can be used. The electron beam used is 50 to 1000 keV, preferably 80 to 300 keV. The irradiation amount of the electron beam is usually about 2 to 15 Mrad.

  The ionizing radiation curable resin is composed of a monomer having a radically polymerizable unsaturated group such as a (meth) acryloyl group or (meth) acryloyloxy group or a cationically polymerizable functional group such as an epoxy group in the molecule. It consists of a polymer or a polymer (hereinafter collectively referred to as a compound). These monomers, prepolymers and polymers are used alone or in combination. In this specification, (meth) acrylate is used in the meaning of acrylate or methacrylate.

  Examples of the prepolymer having a radical polymerizable unsaturated group include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate, polyvinyl Examples include pyrrolidone and the like. This prepolymer usually has a molecular weight of about 10,000 or less. When the molecular weight exceeds 10,000, the cured resin layer has insufficient surface properties such as scratch resistance, abrasion resistance, chemical resistance, and heat resistance. The above acrylates and methacrylates can be used in common, but acrylates are more advantageous for the purpose of being able to cure efficiently at a high speed in a short time because acrylates are faster in terms of crosslinking cure speed with ionizing radiation. It is.

  Examples of the prepolymer having a cationic polymerizable functional group include epoxy resins such as bisphenol type epoxy resins, novolac type epoxy resins, and alicyclic epoxy resins, aliphatic vinyl ethers, aromatic vinyl ethers, urethane vinyl ethers, ester vinyl ethers, etc. And prepolymers such as vinyl ether resins, cyclic ether compounds, and spiro compounds.

  Examples of monomers having a radically polymerizable unsaturated group include (meth) acrylate compound monofunctional monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, methoxyethyl ( (Meth) acrylate, methoxybutyl (meth) acrylate, butoxyethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N , N-diethylaminobutyl (meth) acrylate, N, N-dibenzylaminoethyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, ethyl carbitol (meth) acrylate, phenoxyethyl (meth) acrylate , Phenoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, methoxypropylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2- (meth) acryloyloxypropyl hydrogen terephthalate Etc.

  In addition, as a polyfunctional monomer having a radical polymerizable unsaturated group, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, di Propylene glycol (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tri Propylene glycol di (meth) acrylate, bisphenol-A-di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate , Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerin polyethylene oxide tri (meth) acrylate, tris (meth) acryloyloxy Ethyl Fesford etc. are mentioned.

  The ionizing radiation curable resin is sufficiently cured when irradiated with an electron beam. However, when cured by irradiation with ultraviolet rays, a photopolymerization initiator is added as a sensitizer. In the case of a resin system having a radically polymerizable unsaturated group, photopolymerization initiators are acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, Michler benzoylbenzoate, Michler ketone, diphenyl sulfide, dibenzyl disulfide, diethyl Oxide, triphenylbiimidazole, isopropyl-N, N-dimethylaminobenzoate and the like can be used alone or in combination. In the case of a resin system having a cationically polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, a metatheron compound, a benzoin sulfonate ester, a freeloxysulfoxonium diallyl iodosyl salt, or the like is used alone or as a mixture. be able to. In addition, generally the addition amount of these photoinitiators is about 0.1-10 weight part with respect to 100 weight part of ionizing radiation curable resins.

  As a method of forming the surface protective layer 17 with this ionizing radiation curable resin, for example, the ionizing radiation curable resin is formed into a solution and applied by a known coating method such as a gravure coating method or a roll coating method. can do. The coating amount in this case is suitably about 5 to 30 μm as solid content, more preferably 15 to 25 μm.

  In addition, when imparting further scratch resistance and wear resistance to the surface protective layer 17 formed from an ionizing radiation curable resin, powdered aluminum oxide, silicon carbide, silicon dioxide, calcium titanate, This can be achieved by adding an abrasive such as barium titanate, magnesium pyroborate, zinc oxide, silicon nitride, zirconium oxide, chromium oxide, iron oxide, boron nitride, diamond, and gold sand. The ratio of this abrasive to 100 parts by weight of ionizing radiation curable resin is suitably 1 to 80 parts by weight. Further, if necessary, a lubricant such as silicon resin and wax, a pigment, a matting agent and the like may be added to the surface protective layer.

  As the substrate 11 of the top plate P, a hollow metal plate as shown in FIG. 6 is used in addition to the wood plate as shown in FIG. A typical example of the wood board is a medium density fiber board (MDF). In addition, a single board, a plywood board, a laminated board or the like is used. Moreover, as a hollow metal plate, what processed the steel plate of thickness 0.5mm in the shape like FIG. 6 is mentioned. Each of these includes a top surface portion 11a, a side surface portion 11b surrounding the periphery of the top surface portion 11a, and a boundary of both the top surface portion 11a and the side surface portion 11b, and a curved surface or a chamfered corner portion 11c. It has a shape. And the covering sheet 12 is coat | covered over the side part 11b via the corner | angular part 11c from the top | upper surface part 11a of the board | substrate 11 by post-forming process.

Next, a test performed to complete the present invention will be described. First, 24 types of test bodies (top plates) to be used for the test were produced by changing the resin and thickness used for the reinforcing layer as follows. Here, the covering sheet 12 shown in FIG. 7 is produced, and this covering sheet 12 is bonded to the substrate 11 to produce a top plate.
“Specimen 1”
A base material sheet 15 made of a polypropylene-based thermoplastic elastomer having a thickness of 80 μm and containing a coloring agent is provided, and after corona discharge treatment is performed on both sides thereof, a thickness of 2 μm is formed on one side. While providing a urethane primer layer, printing was performed using the pattern ink 16 on the other surface. As the pattern ink 16, a two-component curable urethane resin binder having a pigment dispersed therein was used.

  Next, on the printed surface using the pattern ink 16, a transparent polypropylene-based thermoplastic elastomer is formed to a thickness of 80 μm with a T-die extruder via a two-component curable urethane adhesive 21. The top sheet 22 was laminated by extrusion. Subsequently, a 2 μm urethane-based primer layer is formed on the surface sheet 22, and an ionizing radiation curable resin (a mixture of urethane acrylate prepolymer and dipentaerythritol hexaacrylate) is formed thereon by a gravure reverse coating method to a thickness of 15 μm. (After drying) It is applied and dried to form an uncured ionizing radiation curable resin layer, and an electron beam (acceleration voltage) is applied to the uncured ionizing radiation curable resin layer in an environment having an oxygen concentration of 200 PPM or less. The surface protective layer 17 made of an electron radiation curable resin was formed by irradiating and curing at 175 keV and a dose of 5 Mrad.

  Then, the reinforcing layer 13 is provided on the surface of the urethane primer layer having a thickness of 2 μm provided on one surface of the base sheet 15. Specifically, the reinforcing layer 13 was provided with a layer of a 300 μm-thick polyester resin (“NOVAPEX GM700” manufactured by Mitsubishi Chemical Corporation) through the two-component curable urethane adhesive 23.

Thus, after producing the covering sheet 12 having the reinforcing layer 13 on the back side of the decorative layer 14, the covering sheet 12 was bonded to the substrate 11 by post-forming. The substrate 11 is coated with a rubber-based adhesive in advance over the top surface, the side surface portion, and the corner portion using MDF in which the corner portion at the boundary between the top surface and the side surface portion surrounding the top surface is curved. I kept it. Then, as shown in FIG. 8, the substrate 11 is placed on the belt conveyor C and traveled with the covering sheet 12 covered, and a plurality of heating rubber rollers Rh are used to sequentially apply from the top surface to the side surface. The covering sheet 12 was bonded to the substrate 11 by pressing. The heating rubber roller Rh is a roller in which the iron core surface is covered with silicon rubber and a heating means is incorporated.
“Specimen 2”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 has a thickness of 400 μm.
“Specimen 3”
The test piece 1 was the same as the test piece 1 except that the polyester resin reinforcing layer 13 was changed to a biaxially stretched polyethylene terephthalate film (“A4300” manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm.
“Specimen 4”
It is the same as Specimen 1 except that the polyester resin reinforcing layer 13 in Specimen 1 is replaced with a 125 μm thick biaxially stretched polyethylene terephthalate film (“A4300” manufactured by Toyobo).
“Specimen 5”
Except that the reinforcing layer 13 of the polyester resin in the test body 1 is changed to a biaxially stretched polyethylene terephthalate film having a thickness of 100 μm (“A4300” manufactured by Toyobo), it is the same as the test body 1.
“Specimen 6”
It is the same as Specimen 1 except that the polyester resin reinforcing layer 13 in Specimen 1 is changed to a 75 μm thick biaxially stretched polyethylene terephthalate film (“A4300” manufactured by Toyobo).
“Specimen 7”
It is the same as Specimen 1 except that the reinforcing layer 13 of polyester resin in Specimen 1 is changed to a biaxially stretched polyethylene terephthalate film (Toyobo “A4300”) having a thickness of 50 μm.
“Specimen 8”
It is the same as Specimen 1 except that the polyester resin reinforcing layer 13 in Specimen 1 is changed to 400 μm thick amorphous polyester (Easterman Chemical Company “EasterPET6763”).
“Specimen 9”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to an amorphous polyester having a thickness of 300 μm (“Easter PET6763” manufactured by Eastman Chemical Company).
"Test body 10"
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to ABS having a thickness of 300 μm (technopolymer “TECNO ABS810”).
"Test body 11"
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to 200 μm thick ABS (“TECNO ABS810” manufactured by Technopolymer).
"Test body 12"
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to ABS having a thickness of 100 μm (technopolymer “TECNO ABS810”).
“Test body 13”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polycarbonate having a thickness of 160 μm (“Iupilon S2000” manufactured by Mitsubishi Engineering Plastics).
“Specimen 14”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polycarbonate having a thickness of 135 μm (“Iupilon S2000” manufactured by Mitsubishi Engineering Plastics).
“Specimen 15”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polycarbonate having a thickness of 85 μm (“Iupilon S2000” manufactured by Mitsubishi Engineering Plastics).
“Specimen 16”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to 330 μm-thick polypropylene (“NOVATEC PPFY3” manufactured by Nippon Polychem).
“Specimen 17”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polypropylene having a thickness of 200 μm (“NOVATEC PPFY3” manufactured by Nippon Polychem).
“Specimen 18”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to 350 μm thick polypropylene (“TX1950” manufactured by Nippon Polychem).
“Specimen 19”
The test piece 1 is the same as the test piece 1 except that the polyester-based resin reinforcing layer 13 is changed to polypropylene having a thickness of 60 μm (“TX1950” manufactured by Nippon Polychem).
“Specimen 20”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polypropylene having a thickness of 380 μm (“F3900” manufactured by Idemitsu Petrochemical Co., Ltd.).
“Test body 21”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polypropylene having a thickness of 200 μm (“F3900” manufactured by Idemitsu Petrochemical Co., Ltd.).
“Test body 22”
The test piece 1 was the same as the test piece 1 except that the polyester resin reinforcing layer 13 was changed to polypropylene having a thickness of 60 μm (“F3900” manufactured by Idemitsu Petrochemical Co., Ltd.).
“Specimen 23”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to 330 μm thick polystyrene (“HF77” manufactured by A & M polystyrene).
“Specimen 24”
The test piece 1 is the same as the test piece 1 except that the polyester resin reinforcing layer 13 is changed to polystyrene having a thickness of 60 μm (“HF77” manufactured by A & M polystyrene).

  About 24 types of test bodies produced above, a DuPont impact test (weight: 500 g, drop height: 300 mm, striking diameter R: 6.3 mm) is performed from the decorative layer side, and the depth of the dent of each test body at that time (Unit: μm) was measured, and the relationship between the dent depth and the physical properties of the reinforcing layer was examined.

As a result, the relationship shown in FIG. 9 was found between the dent depth and the yield point load of each specimen. In other words, the depth of the dent where the dent is not conspicuous is 450 μm or less, and the reinforcing layer at that time is of a resin type and thickness whose yield point load is 9 kgf or more, and the tensile modulus and yield point load of FIG. From the graph showing the relationship, the tensile elastic modulus is 50 kgf / mm ² or more, and the graph showing the relationship between the yield elongation and the yield point load shown in FIG. Furthermore, it is more preferable that the dent is not conspicuous and the decorative layer is hard to break. The resin type and thickness are those having a yield point load of 12 kgf or more and a yield elongation of 3 to 5%. It was found that it is a reinforcing layer made of 9 to 11, the mark ● indicates the most suitable top plate, the mark ▲ indicates that there is no practical problem as the top plate, and the mark × indicates that the top plate is not suitable for use. Show.

It is explanatory drawing which shows the decorative material which comprises the conventional top plate. It is explanatory drawing which shows a mode that a decorative material is bonded together to the board | substrate for top plates. It is sectional drawing which shows an example of the top plate which concerns on this invention. FIG. 4 is a partially enlarged view of FIG. 3. It is a perspective view which shows an example of the board | substrate for top plates. It is a perspective view which shows the other example of the board | substrate for top plates. It is sectional drawing which shows an example of the coating sheet used for the top plate of this invention. It is explanatory drawing which shows a mode that a coating sheet is bonded together to the board | substrate for top plates. It is a graph which shows the relationship between the dent depth of each test body, and a yield point load. It is a graph which shows the relationship between the tensile elasticity modulus of each test body, and a yield point load. It is a graph which shows the relationship between the yield elongation of each test body, and a yield point load.

Explanation of symbols

P Top plate 11 Substrate 11a Top surface portion 11b Side surface portion 11c Corner portion 12 Cover sheet 13 Reinforcing layer 14 Cosmetic layer 15 Base sheet 16 Pattern ink 17 Surface protective layer 21 Adhesive 22 Surface sheet 23 Adhesive

Claims (2)

A top plate in which a covering sheet made of a synthetic resin is bonded to the surface of a substrate, the covering sheet having a yield point load of 9 kgf or more, a tensile elastic modulus of 50 kgf / mm ² or more and a yield elongation in order from the side closer to the substrate. A reinforcing layer made of a synthetic resin having a rate of 3 to 8%, and a surface protective layer made of a cured product of an ionizing radiation curable resin on the surface of the base sheet made of a polyolefin-based thermoplastic resin after decoration. A top plate, which is formed by laminating a formed decorative layer. The substrate has a top surface portion, a side surface portion surrounding the periphery of the top surface portion, and a corner portion at a boundary between both the top surface portion and the side surface portion, and the covering sheet has at least a corner angle from the top surface portion of the substrate. The top plate according to claim 1, wherein the top plate is covered over the side surface portion via the portion.

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