JP2000153584A - Decorative sheet and decorative plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent tearing of a surface even in the case of bending or releasing of an executed print pattern from a film by laminating a surface protective layer obtained by crosslinking curing of an ionizing radiation curable resin, and a plurality of decorative layers each obtained by executing a print pattern on an ionomer resin film. SOLUTION: A surface protective layer 2 obtained by crosslinking curing of an ionizing radiation curable resin is formed at an outermost layer. The layer 2 and a decorative layer 5 obtained by executing a print pattern 4 on an ionomer resin film 3 are laminated to the decorative sheet 1. Then, the pattern 4 is brought into contact with the layer 2 side. Then, an adhesive is provided at an opposite side surface of the sheet 1 to the layer 2 to form the decorative plate laminated with a base plate. Here, the pattern is printed by a suitable ink by considering a material or the like of the film 3. Thus, in the case of bending, tearing of a surface or releasing of the executed pattern from the film can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to the surface of miscellaneous goods, the surface of furniture, the outermost surface of building materials used indoors and outdoors, and the like, and is used for decoration of surfaces and protection of lower layers. The present invention relates to a decorative sheet and a decorative board using the decorative sheet.

[0002]

2. Description of the Related Art A decorative sheet is adhered to the surface of a plywood using an adhesive, and only a portion of the plate is cut off from the plywood side so that a V-shaped groove or a U-shaped groove is formed. There is known a processing method in which the sheet is bent so as to be on the front side. When this processing method is used, the decorative sheet is attached to a flat plate-shaped object, so that the efficiency of the attaching step is high, and by performing bending, it is as if
A product with the appearance of sticking a decorative sheet along the three-dimensional shape made by bending the board first can be obtained, and it is applied to furniture, fittings, speaker boxes, and various other products .

[0003] Conventionally, vinyl chloride resins have been frequently used for this type of application, but in recent years, for various reasons, studies have been made to substitute them with polyolefin resins and the like. However, when a typical polyolefin resin such as polyethylene resin or polypropylene resin is used, a large force is applied to the decorative sheet in the bent part when bending is performed, so the stress suddenly drops after the yield point. These resin films, which cause necking phenomenon, are very susceptible to deformation, and in severe cases the surface is torn, and if a printed pattern is applied, the printed pattern can not follow the deformation of the film and peels off. I often did.

[0004]

Accordingly, in the present invention, while using a polyolefin resin film,
A decorative sheet that eliminates the above-mentioned drawbacks when using a polyethylene resin or a polypropylene resin, has no drawbacks such as a surface tearing even in a bending process, and has no drawbacks in which a printed pattern applied is peeled off from a film; and It is an object of the present invention to provide a decorative board in which various decorative sheets are laminated.

[0005]

In the present invention, at least two layers, a surface protective layer formed by crosslinking and curing an ionizing radiation-curable resin and a decorative layer formed by printing a pattern on an ionomer resin film, are provided. The above-mentioned problems are solved by forming a laminated body, or by forming such a decorative sheet on a substrate.

[0006]

FIG. 1 is a sectional view showing the basic structure of a decorative sheet according to the present invention. The decorative sheet 1 has a surface protective layer 2 obtained by crosslinking and curing an ionizing radiation-curable resin as an outermost layer. The surface protective layer 2 and the decorative layer 5 in which the printed pattern 4 is formed on the ionomer resin film 3 are laminated so that the printed pattern 4 contacts the surface protective layer side. In FIG. 1, the printed pattern 4 is the surface protective layer 2
The ionomer resin film 3
The side without the printed pattern 4 may be laminated in contact with the surface protective layer 2, or the decorative layer having the structure in which the printed pattern 4 is sandwiched between two ionomer resin films may be used as the surface protective layer 2.
May be laminated. Further, the decorative layer as described above may be further laminated with another synthetic resin sheet. Various synthetic resin sheets can be used, for example, polyethylene resin sheets and polypropylene resin sheets.

FIG. 2 shows a decorative plate 6 having a configuration in which the decorative sheet 1 as described above is laminated on a substrate 8 with an adhesive 7 interposed on the surface of the decorative sheet 1 opposite to the surface protective layer 2. Show. Although not particularly shown in FIGS. 1 and 2, an adhesive layer and a primer layer may be provided or a corona treatment or the like may be performed to bond the respective layers.

The surface protective layer 4 is formed by crosslinking and curing an ionizing radiation curable resin. More specifically, the material is an ionizing radiation-curable resin composition obtained by appropriately mixing a prepolymer, oligomer, and / or monomer having a polymerizable unsaturated bond or an epoxy group in a molecule. The thickness of the surface protective layer 4 varies depending on the application, but is preferably 3 to 50 μm. The outer surface of the surface protective layer 4 may be provided with irregularities, if necessary, or minute irregularities for adjusting gloss.

Examples of prepolymers and oligomers constituting the ionizing radiation-curable resin composition include unsaturated polyesters such as condensates of unsaturated dicarboxylic acids and polyhydric alcohols, polyester methacrylates, polyether methacrylates, polyol methacrylates, Methacrylates such as melamine methacrylate, polyester acrylate, epoxy acrylate, urethane acrylate,
Polyether acrylate, polyol acrylate,
Examples include acrylates such as melamine acrylate and cationic polymerization type epoxy compounds.

Examples of monomers in the ionizing radiation-curable resin composition include styrene monomers such as styrene and α-methylstyrene, methyl acrylate, and acrylic acid-2-acrylate.
Acrylic esters such as ethylhexyl, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, methacryl Methacrylic esters such as ethoxymethyl acrylate, phenyl methacrylate and lauryl methacrylate, 2- (N, N-diethylamino) ethyl acrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, phenyl methacrylate, lauryl methacrylate and the like Methacrylates, acrylic acid-2- (N, N-
Diethylamino) ethyl, acrylic acid-2- (N, N-
Dimethylamino) ethyl, acrylic acid-2- (N, N-
Dibenzylamino) methyl, acrylic acid-2- (N, N
-Substituted amino alcohol esters such as -diethylamino) propyl, unsaturated carboxylic acid amides such as acrylamide and methacrylamide, ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-
Compounds such as hexanediol diacrylate and triethylene glycol diacrylate, polyfunctional compounds such as dipropylene glycol diacrylate, ethylene glycol diacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and / or two or more compounds in the molecule Polythiol compounds having a thiol group, for example, trimethylolpropane trithioglycolate, trimethylolpropane trithiopropylate, pentaerythritol tetrathioglycolate and the like can be mentioned.

Usually, as the monomer in the ionizing radiation-curable resin composition, one or a mixture of two or more of the above compounds is used as necessary. In order to provide suitability, it is preferable that the content of the prepolymer or oligomer is 5% by weight or more and the content of the monomer and / or polythiol compound is 95% by weight or less.

When flexibility is required when the ionizing radiation-curable resin composition is applied and cured, the amount of the monomer may be reduced, or an acrylate monomer having one or two functional groups may be used. . When abrasion resistance, heat resistance, and solvent resistance when applying and curing an ionizing radiation-curable resin composition are required, use ionizing radiation such as using an acrylate monomer having three or more functional groups. It is possible to design a curable resin composition. Here, the functional group is 1
Examples thereof include 2-hydroxyacrylate, 2-hexyl acrylate, and phenoxyethyl acrylate. Examples of those having two functional groups include ethylene glycol diacrylate and 1,6-hexanediol diacrylate. Examples of the compound having three or more functional groups include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate.

In order to adjust physical properties such as flexibility and surface hardness when the ionizing radiation-curable resin composition is applied and cured, a resin which is not cured by ionizing radiation irradiation is added to the ionizing radiation-curable resin composition. It can also be added. Specific examples of the resin include the following.
It is a thermoplastic resin such as a polyurethane resin, a cellulose resin, a polyvinyl butyral resin, a polyester resin, an acrylic resin, and polyvinyl acetate. Above all, addition of a polyurethane resin, a cellulose resin, a polyvinyl butyral resin or the like is preferable from the viewpoint of improving flexibility.

When the ionizing radiation-curable resin composition is cured by irradiation with ultraviolet rays, a photopolymerization initiator or a photopolymerization accelerator is added. As the photopolymerization initiator, in the case of a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether or the like is used alone or as a mixture. In the case of a resin system having a cationically polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metaceron compound, a benzoin sulfonic acid ester, or the like is used alone or as a mixture as a photopolymerization initiator. . The addition amount of the photopolymerization initiator,
0.1 parts by weight based on 100 parts by weight of the ionizing radiation-curable resin composition.
It is 1 to 10 parts by weight.

The surface protective layer 2 preferably contains inorganic particles, which are inorganic and have higher hardness than the crosslinked and cured resin, in order to improve the wear resistance of the surface of the layer.
The addition of high hardness spherical particles achieves further surface strengthening. Here, the spherical particles do not need to be true spheres, but may have any smooth surface. The role of the spherical particles is to prevent a part of the surface protective layer from protruding from the surface of the surface protective layer, to receive the external force that causes abrasion on the surface of the spherical particles, and to prevent the wear of the lower layer by gradually wearing the spherical particles themselves. It is. Spherical particles include α-alumina, silica, chromium oxide, iron oxide, diamond, graphite, etc. Among them, spherical α-alumina (shown by Showa Denko KK) Alumina AS-10 to AS
50) can be recommended. The average particle diameter of the spherical particles is 5
１００100 μm is preferred. When inorganic spherical particles are used for the surface protective layer, they may be treated in advance with a silane coupling agent or the like in order to increase the adhesion in the resin constituting the surface protective layer. In addition, a wax such as polyethylene may be added to the surface protective layer in order to improve the scratch resistance of the surface.

The print pattern 4 is formed by an appropriate ink in consideration of the material of the film to be printed (in this case, an ionomer resin film) and the adhesiveness when the print pattern 4 is bonded to another layer. Is formed by printing such as gravure printing. In the present invention, since the printed pattern 4 is provided in contact with the ionomer resin film, the problem of adhesion is unlikely to occur. However, if stronger adhesion is desired depending on the application, a good wet adhesion such as urethane resin is used. It is preferable to use a highly water-soluble resin as a binder for the ink.

The ionomer resin which is a material constituting the ionomer resin film 3 is a thermoplastic copolymer based on an olefin and an α, β-unsaturated carboxylic acid, and has a carboxylic acid group attached to a molecular chain. Some are neutralized by forming salts with metal cations. The olefin is ethylene or propylene, preferably ethylene. The α, β-unsaturated carboxylic acid is acrylic acid or methacrylic acid, preferably methacrylic acid. The metal cation is a lithium, sodium, or zinc cation, preferably zinc.
The ionomer resin has a structure in which the molecular chains are cross-linked with metal cations, and the bond weakens when heated, but has the property of becoming stronger when cooled. Therefore, similarly to the vinyl chloride resin, fusion or embossing by heating (unevenness) It has the advantage of having tough properties at normal temperatures, and has no "necking" in which the stress decreases after the yield point, which is seen with ethylene or propylene, and is tough.
In addition, since it has a carboxyl group in the molecule, it has excellent adhesion to both substances compared to olefins such as ethylene and propylene. Such ionomer resins can be obtained from DuPont under the trade name "Surlyn" or from Mitsui Dupont Polychemicals under the trade name "Himilan". It is preferable that the ionomer resin constituting the decorative sheet 1 contains an ultraviolet absorber as necessary to prevent a decrease in appearance, physical and chemical properties. The thickness of the ionomer resin film 3 is 10
５０50 μm.

The adhesive 7 is selected according to the material of the substrate 8 and the use as a decorative board. The surface of the decorative sheet 1 to be bonded to the substrate 8 may be another resin other than the ionomer resin film. In this case, the bonding with the resin used there is also taken into consideration. Emulsion adhesives such as polyvinyl acetate resin, rubber-based adhesives, and two-component curable adhesives such as epoxy resins and urethane resins can be used.

As the substrate 8, a wood-based, metal-based, or other substrate can be used. As a wooden board, a wood board,
Plywood, particle board, medium-density fiberboard called MDF, and the like can be given. Examples of the metal-based material include those made of aluminum, iron, stainless steel, copper, or the like. Metallic materials are often used after plating. Other examples include ceramic building materials such as gypsum board, calcium silicate board and wood chip cement board, porcelain, glass, enamel, fired tile and the like. In addition to these, a composite such as a fiber-reinforced plastic plate, or a laminate in which an iron plate is pasted on both sides of a paper honeycomb or a sandwich in which a polyethylene resin is sandwiched between two aluminum plates is also used as the substrate 8. Can be used.

The production of the decorative sheet 1 includes, as a series, a pretreatment for improving the adhesiveness, such as a corona treatment or a primer coating, on the ionomer resin film 3 if necessary. Is performed, printing is performed on the processing surface side to provide a printed pattern 4, and thereafter, the printed pattern 4 is covered and coated with an ionizing radiation-curable resin composition. After coating, ultraviolet irradiation or electron irradiation is performed. It is carried out by curing by irradiation with radiation. Embossing may be performed before, during, or after ultraviolet irradiation or electron beam irradiation.

The laminate of the decorative sheet 1 and the substrate 8 is performed by applying an adhesive to one or both of the adhesive surfaces, and if necessary,
After a certain time, both are pressed together. In some cases, heating is performed during the pressing, and there is also a method in which the pressing is left for a certain period of time to complete the bonding.

[0022]

EXAMPLES (Examples) Sheets for printing were prepared as follows. First, a colored polypropylene resin film (manufactured by Mitsubishi Chemical MKV, SB006, thickness 80μ)
m), a polyurethane resin adhesive (manufactured by Dainichi Seika Co., Ltd., Seikabond E295L) was applied so that the applied amount at the time of drying was 10 g per 1 m2, and the adhesive was applied after drying. An ionomer resin (Himilan H1652, manufactured by Du Pont-Mitsui Polychemicals Co., Ltd.) was applied to the surface by extrusion using a T-die so that the thickness became 20 μm. Subsequently, the surface of the ionomer resin was wetted with a wetting index of 40.
Corona discharge treatment was performed so as to be not less than dyn / cm.

A primer of polyurethane resin (AFS, manufactured by Showa Ink Kogyo Co., Ltd.) was applied to the corona discharge treated surface of the sheet obtained above so that the dry coating amount was 2 g per 1 m 2, and then a urethane acrylic resin was applied. (TMK, manufactured by Showa Ink Industry Co., Ltd.), and a grain pattern was printed by a gravure printing method. Further, an electron beam-curable paint (manufactured by Dainichi Seika Co., Ltd., Seika Beam EBS302) containing a urethane acrylate oligomer as a main component is coated on the provided pattern so that the coating amount when dried is 20 per square meter.
g, acceleration voltage 175 KV, irradiation dose 5
Irradiation with an electron beam was carried out under the conditions of Mrad to effect crosslinking and curing to obtain a decorative sheet.

Comparative Example (1) A decorative sheet was prepared in the same manner as in the above example, except that a polypropylene resin was used in place of the ionomer resin. (2) A decorative sheet was prepared in the same manner as in the above example except that a high-density polyethylene resin was used instead of the ionomer resin. (3) A decorative sheet was prepared in the same manner as in Comparative Example (1) except that 1% of polyethylene wax was added to the electron beam-curable paint. (4) A decorative sheet was prepared in the same manner as in Comparative Example (1) except that 3% of polyethylene wax was added to the electron beam-curable paint. (5) A decorative sheet was prepared in the same manner as in Comparative Example (1) except that 5% of polyethylene wax was added to the electron beam-curable paint. (6) A decorative sheet was prepared in the same manner as in the above example except that 1% of polyethylene wax was added to the electron beam-curable paint. (7) A decorative sheet was prepared in the same manner as in the above example, except that 3% of polyethylene wax was added to the electron beam-curable paint. (8) A decorative sheet was prepared in the same manner as in the above example except that 5% of polyethylene wax was added to the electron beam curable paint.

(Evaluation A: Coin Scratch) A decorative sheet obtained in each of the above Examples and Comparative Examples, on the surface of which a convex portion having a height of 50 μm was formed using a hot press, was subjected to a 9 mm thick MDF ( The coin was moved under a load of 2 kg on the test piece adhered to the surface of the medium-density fiberboard) in a direction perpendicular to the convex portion, and the peeling of the surface coating film and the peeling of the printed pattern were observed. (Evaluation B: coin scratch in the bent state) MD was the same as in Evaluation A described above, except that no projection was provided.
A decorative sheet was attached to F, a V-shaped groove having an angle of 90 ° was formed at the same depth as the thickness of the plate from the MDF side, and the decorative sheet side was outwardly bent at a right angle parallel to the groove. Perform coin scratch on the bent part in the same manner as evaluation A,
Peeling of the surface coating film and peeling of the printed pattern were observed. Evaluation A,
In Table B, "B" indicates no peeling of the surface protective layer and no pattern peeling, "B" indicates that either of them slightly peeled off, and "X" indicates that the peeling occurred. (result)

[0026]

[Table 1]

[0027]

According to the present invention, since the decorative pattern is directly provided on the ionomer resin film with the printed pattern, defects such as the case of using a film of polyethylene resin or polypropylene resin are eliminated, and in the bending process, The disadvantage that the surface is torn or the applied printed pattern peels off from the film can be eliminated.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a decorative sheet of the present invention.

FIG. 2 is a schematic sectional view showing a decorative board of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Decorative sheet 2 Surface protective layer 3 Ionomer resin film 4 Print pattern 5 Decorative layer 6 Decorative board 7 Adhesive 8 Substrate

Continued on the front page F-term (reference) 4F100 AK01A AK01C AK07 AK25 AK51G AK70B AT00D BA02 BA03 BA04 BA10A BA10B BA10C BA10D BA15 EJ05A EJ08A EJ53 EJ91 GB08 HB00 HB01 HB31B JB14A JB11 JK10 JK10 L

Claims (3)

[Claims] 1. A decorative sheet comprising at least two layers, a surface protective layer formed by crosslinking and curing an ionizing radiation-curable resin, and a decorative layer having a printed pattern formed on an ionomer resin film. 2. The decorative sheet according to claim 1, wherein a thermoplastic resin film different from the ionomer resin film is laminated on the side of the ionomer resin film or the side of the printed pattern of the decorative layer. 3. A decorative sheet comprising the decorative sheet according to claim 1 and a plate-shaped substrate laminated on the decorative layer side.