JP2002079628A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative sheet not using a vinyl chloride resin sheet, having embossed patterns formed by emboss processing and enhanced in impact resistance so as to hardly generate a depression by a falling article at the time of use as a floor material. SOLUTION: The decorative sheet S comprising a polyolefinic resin and having an embossed pattern 4 formed by emboss processing is constituted by laminating an upper layer 2 comprising an olefinic thermoplastic elastomer and a surface protective layer 3 comprising cured matter of an ionizing radiation curable resin on a lower layer 1 comprising a crystalline polyolefinic resin. A pattern layer 5 or the like is appropriately formed between the upper and lower layers by printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative sheet used for exterior decoration, interior decoration, fittings, furniture, vehicle interior decoration and the like of a building. In particular, the present invention relates to a decorative sheet having a concave-convex pattern formed by embossing and having good impact resistance as a non-PVC-based decorative sheet not using a vinyl chloride resin sheet.

[0002]

2. Description of the Related Art Conventionally, a vinyl chloride resin sheet has been frequently used as a resin sheet as a lower layer or an upper layer of a decorative sheet. However, recently, in consideration of environmental issues, a polyolefin resin is used instead of the resin sheet. Non-PVC resin sheets, such as sheets, have come to be used. For example, JP-A-6-16832 discloses a decorative sheet using an olefin-based thermoplastic elastomer as a polyolefin-based resin. For example, after forming a pattern layer on a resin sheet made of an olefin-based thermoplastic elastomer as a lower layer by printing, a resin sheet made of an olefin-based thermoplastic elastomer as an upper layer is laminated and integrated, and at the same time, an uneven pattern is formed by embossing. A decorative sheet having a configuration in which a colored portion is formed in a concave portion of the uneven pattern by a wiping method and then a surface protective layer is formed.

[0003]

However, if the olefin-based thermoplastic elastomer is used for both the lower layer and the upper layer as described above, the environmental problem caused by the use of the vinyl chloride resin sheet is certainly solved, and the thermal pressure It is also suitable for shaping irregular patterns by embossing, but when a decorative sheet is used as a floor material, for example, dents are easily formed in areas where falling objects fall, and impact resistance is insufficient It was sometimes.

[0004] Therefore, an object of the present invention is to provide not only a good embossing suitability and a concavo-convex pattern by embossing, but also an impact resistance such that dents due to falling objects are less likely to occur when used for flooring or the like. The purpose is to provide a good decorative sheet.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, a decorative sheet according to the present invention is a decorative sheet made of a polyolefin resin and having a textured pattern formed by embossing. An upper layer made of an olefin-based thermoplastic elastomer was laminated on the lower layer, and a surface protective layer made of a cured product of an ionizing radiation-curable resin was further laminated on the upper layer.

As described above, first, since the surface protective layer is formed of a cured product of the ionizing radiation-curable resin, it is hardly scratched, and an olefin-based thermoplastic elastomer is used for the upper layer. By using the water-soluble polyolefin resin, the impact resistance can be improved even in a configuration having good embossing suitability and having an embossed pattern. When a decorative sheet is used as a floor material or the like, the occurrence of dents due to falling objects can be improved.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the decorative sheet of the present invention will be described with reference to the drawings.

[Overview] First, FIG. 1 is a sectional view showing an embodiment of a decorative sheet of the present invention. The decorative sheet S shown in FIG. 1A has an upper layer 2 made of an olefin-based thermoplastic elastomer on a lower layer 1 made of a crystalline polyolefin-based resin.
, A surface protective layer 3 made of a cured product of an ionizing radiation-curable resin is further laminated on the upper layer 2, and an embossed pattern 4 is formed on the upper layer surface. It is.

[0009] The uneven pattern is a kind of decorative treatment. In the structure shown in Fig. 1A, even if all of the lower layer 1, the upper layer 2 and the surface protective layer 3 are non-colored transparent layers, the decorative sheet may be used. Is a decorative sheet that can impart a decorative effect such as a feeling of painting or a sense of design due to a concavo-convex pattern to an adherend to which is adhered. However, usually, the decorative sheet is further subjected to other decorative processing in order to further enhance the design. For example, in the configuration of FIG. 1A, a decoration process is performed in which a lower layer is colored by adding a coloring agent. Alternatively, for example, as illustrated in the following FIG. 1B, a decoration process or the like by printing and forming the picture layer 5 or the like is performed.

That is, the decorative sheet S shown in FIG.
A pattern layer 5 is formed by printing or the like on a lower layer 1 made of a crystalline polyolefin resin, and an upper layer 2 made of an olefin thermoplastic elastomer and a surface protective layer made of a cured product of an ionizing radiation-curable resin are further formed thereon. This is an example of a configuration in which 3 are sequentially laminated, and a concavo-convex pattern 4 is formed on the upper layer side surface by embossing. Note that, in the configuration of FIG. 1B, a configuration in which the lower layer 1 has a color concealing property and the upper layer 2 and the surface protective layer 3 are non-colored and transparent is also a typical configuration.

Although the pattern layer 5 is not essential, it is usually formed on a crystalline polyolefin resin sheet as a lower layer by a printing method or the like in order to express various patterns in terms of design expression. . Then, for the lower layer (printing sheet) on which the pattern layer is formed, the upper layer is formed by a dry lamination method of an olefin-based thermoplastic elastomer sheet,
Alternatively, after laminating the elastomer by a melt extrusion coating method using a T-die or the like, a coating liquid of an ionizing radiation-curable resin is applied and cured to form a surface protective layer, and further, an uneven pattern is formed by embossing. To make a decorative sheet.

Hereinafter, each layer will be described in detail in order.

[Lower Layer] The lower layer 1 is made of a crystalline polyolefin resin. Usually, a resin sheet made of the crystalline polyolefin resin is used for the lower layer. However, the lower layer can be formed by another method such as preparing the upper layer as a surface sheet and forming the surface sheet by a melt coating method of the crystalline polyolefin-based resin. The layer is formed on the topsheet). By using a crystalline polyolefin-based resin for the lower layer, the impact resistance can be improved as compared with the case where the olefin-based thermoplastic elastomer is used for both the upper layer and the lower layer.

As the crystalline polyolefin resin, for example, polyethylene (low density, medium density or high density),
Polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer and the like can be used.

These crystalline polyolefin resins have hydroxyl groups and / or polar groups as polar groups for the purpose of adjusting physical properties such as improvement of adhesion to an upper layer, a picture layer, or another layer in contact with a lower layer such as an adherend. It may have a carboxyl group. For example, hydroxyl group by graft polymerization of ethylene-vinyl alcohol copolymer, etc., maleic acid,
A carboxyl group is introduced with a copolymer such as fumaric acid and itaconic acid. When the polar group is, for example, a hydroxyl group and a carboxyl group, either one or both may be used in combination. Further, the polar group may be a carbonyl group or the like.

The crystalline polyolefin resin may be used alone or in combination of two or more. Further, the lower layer may have a multilayer structure of two layers, three layers, or the like made of layers of different crystalline polyolefin-based resins. In this case, the upper layer side of the lower layer or the back side of the lower layer may be a layer made of a resin having a polar group according to required physical properties such as improvement in adhesion to other layers.

The lower layer may be non-colored and transparent, but may be non-colored and opaque, colored and transparent, colored and opaque (colored and opaque), and the like. In order to color the lower layer, a known coloring agent as described later in the picture layer may be added to the resin. In addition, various additives such as a filler, a flame retardant, and an antioxidant are added to the lower layer as needed.

The lower layer is usually prepared as a resin sheet formed into a sheet (film) by a known film forming method such as a calender method, an inflation method, and a T-die extrusion method. Alternatively, the lower layer resin may be formed on the upper layer resin sheet at the same time as the film formation by the T-die extrusion coating method (EC method). As the resin sheet, any of a stretched sheet and an unstretched sheet can be used.
An unstretched sheet has better formability such as cutting. The thickness of the lower layer depends on the application and the like.
About 300 μm.

The surface of the lower layer that is to be bonded to another layer may be subjected to conventionally known various easy bonding processes, if necessary. For example, surface treatment such as corona discharge treatment, plasma treatment, and ozone treatment, or formation of a primer layer (see reference numeral 7A in FIG. 2). In addition, the primer layer
A known primer, such as a liquid-curable urethane resin or an epoxy resin, may be selected according to the intended use, and may be formed by a known coating method such as roll coating.

[Upper Layer] The upper layer 2 is a layer composed of an olefin-based thermoplastic elastomer. By forming the upper layer as an olefin-based thermoplastic elastomer, good embossing suitability can be maintained. However, when a crystalline polyolefin-based resin is used for the upper layer as well as the lower layer, the width of the embossing conditions (temperature and pressure) becomes narrower, the embossing suitability is not sufficiently obtained, and a good uneven pattern in shape is formed. Cannot be used as a decorative sheet. As described above, when an olefin-based thermoplastic elastomer is used for the lower layer as well as the upper layer, sufficient impact resistance cannot be obtained.

As the olefinic thermoplastic elastomer used for the upper layer, for example, the following can be used.

(1) The soft segment described in JP-B-6-23278 (A) has a number average molecular weight Mn of 25,000 or more, and a ratio Mw / Mn of the mass average molecular weight Mw to the number average molecular weight Mn. 10 to 90% by mass of atactic polypropylene soluble in boiling heptane of ≦ 7,
(B) A soft polypropylene comprising, as a hard segment, a mixture of 90 to 10% by mass of a heptane-insoluble isotactic polypropylene having a melt index of 0.1 to 4 g / 10 min.

Among the olefinic thermoplastic elastomers of this type, isotactic polypropylene, which hardly causes so-called "necking" and has good suitability for forming into various shapes by heat and pressure or embossing, is exemplified by isotactic polypropylene. The mixing ratio with the atactic polypropylene is 5% by mass or more and 50% by mass or less by mass ratio of the atactic polypropylene. The polypropylene-based olefin-based thermoplastic elastomer itself is already known, but when used in a conventionally known application such as a packaging container, the weight ratio of the atactic polypropylene as a soft segment is 5 to emphasize strength. Those having less than mass% were exclusively used. However, when this is applied to a novel use such as forming into a three-dimensional shape or a concavo-convex shape or embossing, necking occurs as described above, and good processing cannot be performed. Therefore, contrary to the conventional design of the composition, in the olefin-based thermoplastic elastomer of polypropylene, the mass ratio of the atactic polypropylene is set to 5% by mass or more, thereby embossing or three-dimensional shape or the like. It is possible to eliminate non-uniform sheet deformation due to necking in forming an uneven article surface shape, and resulting defects such as wrinkles and pattern distortion. Particularly, the case where the mass ratio of the atactic polypropylene is 20% by mass or more is preferable. On the other hand, if the mass ratio of atactic polypropylene increases too much,
The sheet itself is easily deformed, and when the sheet is passed through a printing press, the sheet is deformed, a pattern is distorted, and defects such as misregistration in multicolor printing easily occur. Further, it is not preferable because it is easily broken during molding. As the upper limit of the mass ratio of the atactic polypropylene, the pattern layer is printed using a normal rotary printing machine such as rotary gravure printing, and embossing of the sheet, vacuum forming, V-cut processing, simultaneous lamination of injection molding, etc. 50 to hire
% By mass, more preferably 40% by mass or less.

(2) A thermoplastic elastomer comprising an ethylene-propylene-butene copolymer resin. Here, as the butene, any of the three structural isomers of 1-butene, 2-butene and isobutylene can be used. Preferred specific examples of the ethylene-propylene-butene copolymer, which is a random copolymer and partially includes an amorphous portion, include the following (i) to (iii). (i) Those described in JP-A-9-111055. It is a random copolymer of a terpolymer of ethylene, propylene and butene. The mass ratio of the monomer components is 90% by mass or more of propylene. The melt flow rate is preferably 1 to 50 g / 10 minutes at 230 ° C. and 2.16 kg. And, for 100 parts by mass of such a ternary random copolymer, 0.01 to 50 parts by mass of a transparent nucleating agent containing a phosphate aryl ester compound as a main component,
It is obtained by melting and kneading 0.003 to 0.3 parts by mass of a fatty acid amide having 12 to 22 carbon atoms. (ii) Those described in JP-A-5-77371. this is,
80 to 0% by mass of a crystalline polypropylene is added to 20 to 100% by mass of an amorphous polymer having a propylene content of 50% by mass or more, which is a terpolymer of ethylene, propylene and 1-butene. It is. (iii) Those described in JP-A-7-316358. This is a terpolymer of ethylene, propylene, and 1-butene, and the content of propylene and / or 1-butene is 50% by mass or more and 20 to 100% by mass of the low crystalline polymer. 0.5% by mass of an oil gelling agent such as N-acylamino acid amine salt or N-acylamino acid ester is added to a composition in which 80 to 0% by mass of a crystalline polyolefin such as isotactic polypropylene is mixed. It becomes.

The ethylene-propylene-butene copolymer resin may be used alone, or may be used in the above (i) to (iii).
If necessary, another polyolefin-based resin may be mixed and used.

(3) As described in JP-B-53-21021, (A) an olefin polymer (crystalline polymer) such as polyethylene, polypropylene or polymethylpentene is used as a hard segment, and (B) a partial cross-linking Monoolefin copolymer rubbers such as ethylene-propylene copolymer rubber and unsaturated ethylene-propylene-non-conjugated diene terpolymer rubber are used as soft segments, and these are uniformly blended and mixed. . In addition,
Monoolefin rubber / olefin polymer = 50 / 50-
Mix at a ratio of 90/10 (mass ratio).

(4) As described in JP-B-53-34210, etc., (B) an uncrosslinked monoolefin copolymer rubber (soft segment) and (A) an olefin copolymer (crystallinity, hard segment) ) And a cross-linking agent, and is heated to apply shear stress to dynamically partially cross-link an olefin-based elastomer. (B) monoolefin rubber / (A) olefin copolymer = 60/40 to 80/20
(Mass ratio).

(5) As described in JP-B-56-15741, (A) isotactic polypropylene, propylene-ethylene copolymer, propylene-butene-1
A peroxide-decomposable olefin polymer (hard segment), which decreases its molecular weight when mixed and heated with a peroxide such as a copolymer to increase fluidity, and (B) ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene Peroxide-crosslinked monoolefin copolymer rubber (soft segment), which crosslinks and reduces fluidity by mixing and heating with a peroxide such as an original copolymer rubber, (C)
Peroxide non-crosslinked hydrocarbon rubber (soft segment / fluidity-modifying component) that does not crosslink even when mixed and heated with peroxides such as polyisobutylene and butyl rubber and has constant fluidity, and (D) paraffinic and naphthene An olefin-based elastomer obtained by mixing a mineral oil-based softener such as an oil-based or aromatic oil-based softener and dynamically heat-treating the mixture in the presence of an organic peroxide. (A) is 90 to 40 parts by mass, (B) is 10 to 60 parts by mass.
In parts by mass, (A) + (B) = 100 parts by mass.
(C) and / or (D) have a compounding ratio of 5 to 100 parts by mass.

(6) An olefin-based thermoplastic elastomer comprising an ethylene-styrene-butylene copolymer as described in JP-A-2-139232.

(7) A hydroxyl group or / and / or a polar group
And the above (1) to (6) having a carboxyl group.
Olefinic thermoplastic elastomer. For example, an olefin-based thermoplastic elastomer in which a hydroxyl group is introduced by graft polymerization of an ethylene-vinyl alcohol copolymer or the like and a carboxyl group is introduced by a copolymer of maleic acid, fumaric acid, itaconic acid or the like is used. When the polar group is, for example, a hydroxyl group and a carboxyl group, either one or both may be used in combination. Further, the polar group may be a carbonyl group or the like. These polar groups are
It has an effect of improving the adhesion between another layer formed in contact with the upper layer such as the surface protective layer and the picture layer and the upper layer.

The above olefinic thermoplastic elastomers may be used alone or in combination of two or more. Further, the upper layer may have a multilayer structure of two layers, three layers, or the like made of different olefin-based thermoplastic elastomer layers.
In this case, the lower layer side of the upper layer, or the surface protective layer side of the upper layer, may be provided in accordance with required physical properties such as improvement in adhesion to these other layers.
It may be a layer made of a resin having a polar group.

Further, various additives such as a coloring agent, a filler, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer are added to the upper layer as needed. When a picture layer is provided below the upper layer, the upper layer is transparent (uncolored or colored) so that the picture layer can be seen through. If there is no picture layer, it may be opaque.

The ultraviolet absorber may be an organic ultraviolet absorber such as a benzotriazole-based, benzophenone-based or salicylate-based ultraviolet absorber, and may have a particle diameter of 0.2 μm.
Inorganic substances such as the following fine particles of zinc oxide, cerium oxide, and titanium oxide can be used. As a light stabilizer,
A radical scavenger such as a hindered amine radical scavenger such as bis- (2,2,6,6-tetramethyl-4-piperidinyl) sebacate and a piperidine radical scavenger can be used.

The upper layer is formed in advance by a calender method,
The resin sheet formed into a sheet (film) by a known film forming method such as an inflation method or a T-die extrusion method is applied to a resin sheet as a lower layer. It can be formed by lamination by dry lamination or heat fusion. Or,
The resin for the upper layer is compared with the resin sheet for the lower layer by T
It may be formed simultaneously with the film formation by the die extrusion coating method (EC method). If it is necessary to enhance the adhesive strength during dry lamination, heat fusion, or T-die extrusion coating, an adhesive layer made of an appropriate adhesive such as a two-component curable urethane resin or epoxy resin (see FIG. 2) It is preferable to laminate with an adhesive layer 8 interposed therebetween.

The resin sheet of the olefin-based thermoplastic elastomer can be used as a stretched sheet or an unstretched sheet, but the unstretched sheet is more suitable for molding such as V-cut processing. The thickness of the upper layer depends on the application and the like, but is usually about 20 to 300 μm.

The surface of the upper layer that is to be bonded to another layer may be subjected to conventionally known various easy bonding processes, if necessary. For example, surface treatment such as corona discharge treatment, plasma treatment, and ozone treatment, or formation of a primer layer (see the primer layer 7B in FIG. 2). The primer layer may be formed by a known coating agent such as a two-component curable urethane resin or an epoxy resin depending on the application, and by a known coating method such as roll coating.

[Surface Protective Layer] The surface protective layer 3 is formed as a cured product of an ionizing radiation curable resin. The surface protective layer can improve surface properties such as scratch resistance and scratch resistance that are hardly abraded and stain resistance. In particular, the surface hardness required for abrasion resistance or abrasion resistance is a particularly preferable surface property when the decorative sheet is used for flooring.

The surface protective layer is usually transparent (uncolored or colored) so that a picture layer is formed below the surface protection layer so that the picture layer can be seen through. If there is no picture layer,
It may be opaque. This surface protective layer can also be used as one of the decorative treatments for adjusting the gloss and imparting a design such as a feeling of painting. The formation of the surface protective layer is performed by applying a known coating method such as gravure coating or roll coating on the upper layer using a coating liquid composed of an ionizing radiation-curable resin, and then irradiating the resin with ionizing radiation to cure the resin. It is formed by making a cured product. In addition, the thickness of the surface protective layer is usually about 1 to 10 μm.

In the present invention, the surface protective layer is formed as a cured product of an ionizing radiation-curable resin.
Compared with the case where other thermoplastic resins or thermosetting resins are used, surface physical properties such as surface hardness including resistance to dent scratches can be easily improved. In addition, as the resin of the surface protective layer, in terms of productivity, an ionizing radiation-curable resin having a higher curing speed than the thermosetting resin is preferable, and further,
Among ionizing radiation-curable resins, ionizing radiation-curing resins (electron-curing resins) are cured by electron beams rather than ionizing radiation-curing resins (ultraviolet-curing resins) because they can be instantaneously cured. Resin) is more preferred.

The ionizing radiation-curable resin is a composition curable by ionizing radiation. Specifically, a prepolymer (a so-called oligomer) having a radically polymerizable unsaturated bond or a cationically polymerizable functional group in the molecule. And / or a monomer that is appropriately mixed and curable by ionizing radiation. These prepolymers or monomers are used alone or as a mixture of two or more. The curing reaction is usually a crosslinking curing reaction.

The above-mentioned prepolymer or monomer specifically has a radical polymerizable unsaturated group such as a (meth) acryloyl group and a (meth) acryloyloxy group, a cationic polymerizable functional group such as an epoxy group in the molecule. Consisting of a compound having Further, a polyene / thiol prepolymer based on a combination of polyene and polythiol is also preferably used. In addition, for example, a (meth) acryloyl group is
It means an acryloyl group or a methacryloyl group. Examples of the prepolymer having a radical polymerizable unsaturated group include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate, and silicone (meth) acrylate. Etc. can be used. A molecular weight of about 250 to 100,000 is usually used.

Examples of the monomer having a radical polymerizable unsaturated group include monofunctional monomers such as methyl (meth)
There are acrylate, 2-ethylhexyl (meth) acrylate, phenoxyethyl (meth) acrylate and the like.
Also, as polyfunctional monomers, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylpropane tri (meth)
There are also acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like. Examples of prepolymers having a cationically polymerizable functional group include prepolymers of epoxy resins such as bisphenol epoxy resins and novolak epoxy compounds, and vinyl ether resins such as fatty acid vinyl ethers and aromatic vinyl ethers. Examples of the thiol include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. Examples of the polyene include those obtained by adding allyl alcohol to both ends of a polyurethane made of a diol and a diisocyanate.

When curing with ultraviolet light or visible light, a photopolymerization initiator is further added to the ionizing radiation-curable resin. In the case of a resin system having a radical polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ethers can be used alone or in combination as a photopolymerization initiator. 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 metallocene compound, a benzoinsulfonic acid ester, or the like is used alone or as a mixture as a photopolymerization initiator. be able to. In addition,
The addition amount of these photopolymerization initiators is about 0.1 to 10 parts by mass with respect to 100 parts by mass of the ionizing radiation-curable resin.

As the ionizing radiation, electromagnetic waves or charged particles having energy capable of causing a curing reaction of the molecules in the ionizing radiation-curable resin (composition) are used. What is usually used is ultraviolet rays or electron beams.
It is also possible to use visible light, X-rays, ion beams and the like.
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, and a metal halide lamp is used. As a wavelength of the ultraviolet light, a wavelength range of 190 to 380 nm is usually mainly used. As the electron beam source, various types of electron beam accelerators such as Cockcroft-Walton type, Van degraft type, resonance transformer type, insulating core transformer type, or linear type, dynamitron type, high frequency type, etc. are used, preferably 100 to 1000 keV, preferably. A device that irradiates electrons having an energy of 100 to 300 keV is used.

Further, a thermoplastic resin such as a vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, an acrylic resin, or a cellulose resin may be added to the ionizing radiation-curable resin, if necessary. it can.

Further, various additives may be further added to the ionizing radiation-curable resin as required. These additives include matting agents such as calcium carbonate and silica, lubricating agents such as alumina and silica, ultraviolet absorbers, light stabilizers, coloring agents and the like.

[Uneven Pattern] The uneven pattern 4 may be formed by a known embossing process (heating press). The concavo-convex pattern is usually formed on the upper surface of the upper layer. The embossing is performed by pressing an embossing plate on the surface of a heat-softened resin sheet using a hot press type sheet-fed or rotary embossing machine. The embossing is performed by, for example, a so-called doubling embossing method in which a resin sheet as a lower layer and a resin sheet as an upper layer are laminated, and at the same time, the upper and lower surfaces of the resin sheet as the upper layer are formed by embossing with hot pressure. Is also good. Alternatively, embossing may be performed on the resin sheet after the lower layer and the upper layer are laminated or on the lower layer before the lamination. In addition, as the uneven pattern, a wood grain board conduit groove, a stone board surface unevenness (granite cleavage plane, etc.), a cloth surface texture, a satin finish, a grain, a hairline,
It is a linear groove. In addition, the uneven pattern is usually the upper surface of the upper layer, but may be the upper surface of the lower surface, the lower surface of the lower surface, or the lower surface of the lower layer.

As a further decoration process, FIG.
As an example of the decorative sheet S, the colored portions 6 can be formed by filling the concave portions of the uneven pattern 4 with a coloring ink by a known wiping method (see Japanese Patent Publication No. 58-14312). The coloring ink can be the same as the pattern layer described below. However, from the viewpoint of abrasion resistance, a material using a two-component curable urethane resin as a binder is preferable. Note that the wiping method may be any of conventionally used wiping methods such as a dodder blade method and a roll coating method. In other words, the colored ink is applied to the entire surface of the concave and convex pattern, and thereafter, the ink of the convex portion is scraped off with a dough blade, a sponge roll, a cloth, or the like, or is wiped off so that the colored ink remains in the concave portion. I do. In addition,
Although the colored portion may be formed after the formation of the surface protective layer, it is usually formed before forming the surface protective layer so as to be below the surface protective layer 3 as shown in FIG.

[Picture Layer] Further, as a further decoration process, usually, as a decoration layer, as shown in FIG.
Is often formed. The picture layer 5 is formed of ink by a known printing method such as gravure printing, offset printing, silk screen printing, transfer printing from a transfer sheet, sublimation transfer printing, ink jet printing, and the like. Further, in the case of a solid pattern on the entire surface, it can be formed with a coating material by a known coating method such as gravure coating or roll coating. Examples of the pattern of the picture layer include a wood grain pattern, a stone grain pattern, a cloth grain pattern, a leather pattern, a geometric figure, a character, a symbol, and a solid image on the entire surface. Note that the picture layer is also used in combination with a pattern pattern layer expressing a pattern such as a wood grain pattern and a solid layer on the entire surface. The entire solid layer is usually used as a concealing layer, a colored layer, a colored concealing layer, and the like.

The pattern layer is usually formed on the resin sheet as the lower layer 1 so that it is formed on the surface of the lower layer 1 as in the decorative sheet S illustrated in FIG. 1B. In addition, the pattern layer may be the lower surface, the upper and lower surfaces, or when the upper layer is formed of a resin sheet, the lower surface, the upper surface, the upper surface and the lower surface of the resin sheet.

The ink (or) paint used for forming the picture layer may be a polyester resin, a urethane resin, an acrylic resin, a vinyl acetate resin, a vinyl chloride-vinyl acetate copolymer, a cellulose resin, or a chlorine resin. Chlorinated polyolefin resins such as chlorinated polyethylene and chlorinated polypropylene are used alone or in combination of two or more. Examples of the colorant used in the ink (or) paint include inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine, cobalt blue, titanium yellow, graphite, and carbon black; isoindolinone yellow; Yellow A, quinacridone red, permanent red 4R, organic pigments (or dyes) such as phthalocyanine blue, indathrene blue RS, and aniline black; metal pigments composed of metal powders such as aluminum and brass; titanium dioxide-coated mica; A pearlescent (pearl) pigment, a fluorescent pigment, or the like, which is made of foil powder such as a lead carbonate, is used alone or in combination of two or more.

The picture layer is one of the representative layers formed as a decoration layer, but a metal thin film layer or the like may be formed as a decoration layer. The metal thin film layer is formed using a metal such as aluminum, chromium, gold, silver, and copper by a method such as vacuum evaporation and sputtering. Alternatively, a combination of these may be used. The metal thin film layer may be provided on the entire surface, or
It may be provided partially in a pattern.

[Applied Body of Decorative Sheet] The use of the decorative sheet of the present invention is not particularly limited. The adherend is a plate material such as a flat plate or a curved plate of various materials, a three-dimensional article, a sheet (or film), or the like. For example, wood veneer, wood plywood, particle board, wood material such as wood fiber board such as MDF (medium density fiber board), wood board material used as three-dimensional article, plate material such as iron and aluminum, three-dimensional article or Ceramics used as metal materials used as sheets, ceramics such as glass and ceramics, non-cement ceramic materials such as gypsum, non-ceramic ceramic materials such as ALC (lightweight cellular concrete) plates, etc. Material, acrylic resin, polyester resin, polystyrene resin, polyolefin resin such as polypropylene,
ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenolic resin, vinyl chloride resin, cellulosic resin, rubber or other plate material, resin material used as a three-dimensional article or sheet, or high quality paper used exclusively as a sheet , Paper such as Japanese paper, non-woven fabric or woven fabric made of fibers such as carbon, asbestos, glass and synthetic resin, or a composite material of these two or more materials, for example, wood used as a plate material or a three-dimensionally shaped article, etc. Composite (base) materials such as powdered plastics, paper powdered plastics, and FRP (fiber reinforced plastics) are exemplified.

[Laminating method of decorative sheet on adherend] As a method of laminating the decorative sheet on the adherend, for example, (1) a plate-shaped adherend is pressed onto an adherend with a pressure roller via an adhesive. (2) As described in JP-B-50-19132, JP-B-43-27488, etc., a decorative sheet is placed between male and female molds for injection molding and then melted. A so-called simultaneous injection molding laminating method in which a resin is injected into a mold and a decorative sheet is adhered and laminated on the surface of the adherend as a resin molded product at the same time as the molding, (3) Japanese Patent Publication No. 56-4576.
No. 8, Japanese Patent Publication No. 60-58014, etc., a decorative sheet is opposed to or placed on the surface of a three-dimensional adherend with an adhesive therebetween, and is placed from the adherend side. A so-called vacuum forming and laminating method of laminating a decorative sheet on the surface of an adherend by at least a pressure difference caused by the combined use of vacuum suction and pressurized air pressing from the decorative sheet side, (4) JP-B-61-5
No. 895, JP-B-3-2666, etc., while supplying a decorative sheet through an adhesive in the long axis direction of a columnar adherend such as a column or a polygonal column, By a plurality of rollers having different directions, decorative sheets are successively pressed and adhered to a plurality of side surfaces constituting an adherend and laminated.
There is a so-called lapping method.

Further, as a further processing method for a decorative sheet obtained by laminating decorative sheets, Japanese Utility Model 15-31
No. 122, JP-A-48-47972, first, a decorative sheet is laminated on a plate-shaped adherend with an adhesive therebetween to form a decorative sheet, and the decorative sheet is on the side opposite to the decorative sheet. A groove having a V-shaped or U-shaped cross section which reaches the interface between the decorative sheet and the adherend, and then applying an adhesive in the groove, and bending the groove to form a box body Alternatively, there is a bending method such as a so-called V-cut or U-cut method for forming a columnar body.

[Uses of the decorative sheet and its laminate] The decorative sheet of the present invention is laminated on various adherends, subjected to predetermined molding processing as required, and used for various purposes. For example,
Interior decoration of buildings such as walls, ceilings and floors, surface decoration of fittings such as window frames, doors, handrails, surface decoration of furniture or cabinets of light electric / OA equipment, vehicle interiors such as cars and trains, aircraft interiors,
Ship interiors, window glass makeup, etc. In particular, the decorative sheet of the present invention is suitable for floors and the like in that it has good impact resistance such that dents due to falling objects are unlikely to occur.

[0057]

EXAMPLES The decorative sheet of the present invention will be further described below with reference to examples.

Example 1 A decorative sheet S for flooring having a structure as shown in FIG. 2 was produced as follows. First, as a resin sheet for the lower layer 1, a resin in which a coloring agent is added to a polypropylene-based crystalline polyolefin-based resin is formed by a T-die extrusion method to prepare a 60-μm-thick yellow-brown opaque resin sheet. did.

After subjecting one surface of the resin sheet to a corona discharge treatment, a two-part curable urethane resin-based primer comprising a urethane acryl polyol and a hexamethylene diisocyanate-based curing agent is gravure-coated to form a primer layer. 7A was formed, and as a pattern layer 5, a colored solid layer 5A and a grain pattern pattern layer 5B were sequentially formed by gravure printing to obtain a printed sheet. As the binder resin for the picture layer, a two-part curable urethane resin consisting of urethane acrylic polyol and a hexamethylene diisocyanate-based curing agent was used for the colored solid layer, and a urethane acrylic polyol resin was used for the pattern layer.

Then, a two-part curable urethane resin-based adhesive composed of urethane acryl polyol and a hexamethylene diisocyanate-based curing agent is applied to the surface of the printed sheet on which the picture layer is to be formed by a roll coating method and dried.
Forming an adhesive layer 8 having a solid content of 10 g / m ² ,
Then, a resin obtained by adding a benzotriazole-based ultraviolet absorber and a hindered amine-based light stabilizer to an ethylene-propylene-butene terpolymer-based olefin-based thermoplastic elastomer was applied to a thickness of 8 by a T-die extrusion coating method.
An upper layer 2 of 0 μm, which is colorless and transparent, is laminated at the same time as film formation,
This was a laminated sheet.

Next, after subjecting the upper surface of the laminated sheet to corona discharge treatment, a primer consisting of a two-part curable urethane resin consisting of a urethane acrylic polyol and a hexamethylene diisocyanate-based curing agent was applied by a gravure coating method. Apply over the entire surface and apply 1 g / m ²
After forming the primer layer 7B, a urethane acrylate-based ionizing radiation (electron beam) curable resin paint is applied by a roll coating method at a solid content of 15 g / m ^{2, and is} applied with an electron beam irradiation device at 125 keV. 50kGy (5Mra
d) Irradiation with an electron beam under the condition of an oxygen concentration of 200 ppm or less was carried out for crosslinking and curing to form an uncolored transparent surface protective layer 3. Then, the sheet was embossed through a roll embossing machine to form an embossed pattern 4 from a satin embossed plate having a plate depth of 100 μm to obtain a decorative sheet S as shown in the sectional view of FIG. In FIG. 2 which is a conceptual diagram, the deformation of the layer due to the embossing is illustrated as up to the upper layer 2, but the deformation of the layer may reach the lower layer 1 depending on the depth of the concave portion of the uneven pattern.

Comparative Example 1 The procedure of Example 1 was repeated except that the resin used for the lower layer was changed to the olefinic thermoplastic elastomer used for the upper layer (however, the colorant was added in the same manner as the lower layer of Example 1). In the same manner as in Example 1, a decorative sheet was obtained.

Comparative Example 2 The procedure of Example 1 was repeated except that the resin used for the upper layer was changed to a crystalline polyolefin resin used for the lower layer (however, no coloring agent was added as in the upper layer of Example 1). In the same manner as in Example 1, a decorative sheet was obtained.

[Evaluation of Performance] Impact resistance and suitability for embossing were evaluated as follows. The evaluation results are shown in Table 1.

(1) Impact resistance: A two-component curable urethane resin-based primer was applied to the back surface of the decorative sheet at a solid content of 1.5.
g / m ² gravure coating, and a ^2- mm curable urethane resin-based adhesive applied to a 4 mm thick MDF (medium density fiberboard) with a wet lamination of 70 g / m ² using a roll laminator. It was pressed for 30 minutes with a cold press to prepare a decorative plate for evaluation. The decorative plate was subjected to an evaluation test using a Dupont-type impact tester under the conditions of a shooting die radius of 6.35 mm, a weight of 500 g, and a weight drop height of 30 cm in accordance with JIS K 5400. The depth was measured using a surface roughness measuring instrument, and the magnitude of the depth was evaluated. A depth of less than 300 μm was good, and a depth of 300 μm or more was bad.

(2) Suitability for embossing: When embossing to form an uneven pattern on the surface with an embossing machine at the stage of manufacturing a decorative sheet, the sheet heating temperature is set to 140 ° C.
The evaluation was performed at three points of 50 ° C. and 160 ° C., and the shape of the concavo-convex pattern was visually observed and evaluated. If the uneven pattern is uniformly and sufficiently shaped, it is good, or the shaping is not sufficient,
Those that were not uniformly shaped were regarded as defective.

[0067]

[Table 1]

As a result of the performance evaluation, as shown in Table 1, in Example 1, the impact resistance was good with a concave depth of 265 μm, and the embossing suitability was good at both 150 ° C. and 160 ° C.
The performance was sufficient for practical use in manufacturing. On the other hand, in Comparative Example 1 in which an olefin-based thermoplastic elastomer was used for both the lower layer and the upper layer, the embossing suitability was 140 ° C, 150 ° C and 1 ° C.
Although good at all temperatures of 60 ° C., the impact resistance was poor with a dent depth of 335 μm. Comparative Example 2 using a crystalline polyolefin-based resin for both the lower layer and the upper layer
Had good impact resistance with a depression depth of 252 μm, but had good embossing aptitude only at 160 ° C. and bad at 140 ° C. and 150 ° C., and had a narrow temperature range and insufficient performance for practical use in production. .

[0069]

According to the decorative sheet of the present invention, it is possible to improve the impact resistance as well as to prevent abrasion due to the configuration having an uneven pattern by embossing. As a result, when the decorative sheet is used as a floor material or the like, dents caused by falling objects can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a decorative sheet according to the present invention.

FIG. 2 is a sectional view showing another embodiment of the decorative sheet of the present invention.

[Explanation of symbols]

 Reference Signs List 1 lower layer 2 upper layer 3 surface protective layer 4 uneven pattern 5 picture layer 5A colored solid layer 5B pattern pattern layer 6 colored portion 7A, 7B primer layer 8 adhesive layer S decorative sheet

Continued on front page F-term (reference) 2B002 AA08 BA01 BA17 BB06 DA01 DA02 DA03 DA04 DA06 2B250 AA01 AA05 AA06 AA09 AA11 AA13 AA21 AA31 AA40 BA03 BA05 CA11 DA04 EA01 EA13 FA21 FA28 FA31 GA03 4F100 AH03AK03 AK01 AK01 AK01 AK01 AK01 AK25 AK51 AK51G AK80 AL01 AL06 AL09B BA03 BA07 BA10A BA10C BA15 CA05 CA07 CB00 EJ39 EJ55 EJ65 GB08 GB31 GB81 HB31 JA11A JB14C JB16B JK10 JK12 JL16

Claims (1)

[Claims] 1. A decorative sheet comprising a polyolefin resin and having an embossed pattern formed thereon by embossing, wherein an upper layer comprising an olefin thermoplastic elastomer is laminated on a lower layer comprising a crystalline polyolefin resin, A decorative sheet in which a surface protective layer made of a cured product of an ionizing radiation-curable resin is laminated on an upper layer.