JPH11207876A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a decomposition or an elution of an ultraviolet absorbent at the time of embossing in a manufacturing step or at the time of using for a long period as a product by decorating a base material sheet made of an olefin thermoplastic elastomer and containing an inorganic ultraviolet absorbent. SOLUTION: The decorative sheet 1 is obtained by forming a design print layer 13b on a rear surface of a base material sheet 11 made of a transparent olefin thermoplastic elastomer. An inorganic ultraviolet absorbent 19 is added into the sheet 11. The absorbent 19 absorbs to shut OFF an ultraviolet ray in the sheet 11 itself and arriving at the layer 13b under the sheet 11 to prevent occurrence of a fading, a releasing, a strength decrease, a crack or the like. The sheet 1 suitably further contains a hindered amine radical scavenger in the base material sheet or a surface protective sheet containing the absorbent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to the interior of buildings, the interior decoration of fittings, the interior of vehicles, etc. by being attached to the surface of various types of wood-based substrates, ceramic-based inorganic substrates, metal-based substrates, etc. The present invention relates to a decorative sheet for surface decoration having a high design effect, which is used as a decorative board.

[0002]

2. Description of the Related Art As a decorative sheet for surface decoration used in the interior of a conventional building, a decorative sheet formed by using a polyvinyl chloride resin sheet as a base material and performing a decoration process by printing a picture or the like is used. I have been. Such a decorative sheet can be enhanced in aesthetic appearance by, for example, printing a pattern such as wood grain or performing other decorative processing.

However, the above-mentioned conventional decorative sheet uses a polyvinyl chloride resin as a material,
Since chlorine gas is generated during combustion, there is a problem of environmental pollution.

[0004] In order to solve the above-mentioned problem, a decorative sheet formed by using a olefin-based thermoplastic elastomer as a sheet base material and performing a decoration treatment by printing a picture or the like has been proposed in JP-A-6-79830. I have. Olefin-based thermoplastic elastomers do not generate chlorine-based gas during combustion and have no problem of environmental pollution.

[0005] In the decorative sheet using the above-mentioned olefin-based thermoplastic elastomer as a sheet base material, when a printed layer of a pattern is provided as a decorative treatment, the purpose of this method is to suppress the fading of the printed layer and protect the printed layer. In the olefin-based thermoplastic elastomer sheet placed on the upper layer of the printing layer,
Benzotriazole compounds, salicylate compounds,
An organic ultraviolet absorber, which is roughly classified into a benzophenone compound or a cyanoacrylate compound, is added.

[0006]

However, the above-mentioned organic ultraviolet absorber has a weather resistance required for interior use (durability up to 1000 hours irradiation in a WOM test described later). Sheets or decorative sheets that are not subjected to thermal processing such as embossing can be used somehow, but are still insufficient for exterior use or decorative sheets with thermal processing, and have low heat resistance and durability. There was a problem. For example, when embossing the decorative sheet surface as a decoration process, it volatilizes or decomposes to lower the ultraviolet absorbing ability, contaminates the embossing roller, or dissolves (bleeds) to the sheet surface to remove the ultraviolet light. For example, the adhesive strength with an overcoat layer formed on the upper layer is reduced.

In addition, when the above-mentioned organic UV absorber is used as a decorative sheet for a long period of time, decomposition or thermal decomposition occurs due to the absorption of UV light, and the UV-absorbing ability is reduced, or the laminate constituting the decorative sheet is laminated. The problem is that the adhesion strength between the layers of the body is reduced, or that when exposed to sunlight, the amount of ultraviolet absorber in the base material is reduced due to the elution with time, resulting in a decrease in light resistance (weather). There is. For example, a conventional decorative sheet containing the above-mentioned organic ultraviolet absorber in an olefin-based thermoplastic elastomer sheet is a carbon arc lamp type sunshine weatherometer (Weather-O-Meter) weather resistance deterioration acceleration test (hereinafter referred to as W.I.
O. M test), the adhesion strength between the layers decreased after 2000 hours. Here, W. O. The conditions for the M test were as follows: JIS-A-14
Using a carbon arc lamp sunshine weatherometer (Weather-O-Meter) tester specified in No. 15 (black panel temperature: 63 ° C., rainfall time:
The conditions were rainfall (water spraying for 18 minutes during 120 minutes). Among the decorative sheets, particularly as decorative sheets for exterior use, the above-mentioned W.I. O. In the M test, weather resistance of 3000 hours or more is required.

The present invention has been made in view of the above circumstances, and therefore, the present invention decomposes or elutes the ultraviolet absorber during embossing in a manufacturing process or during long-term use as a product. A cosmetic with excellent heat resistance, durability and weather resistance that can protect the print layer by preventing discoloration of the base sheet or surface protective film sheet itself or the print layer thereunder over a long period of time. The purpose is to provide a sheet.

[0009]

Means for Solving the Problems To achieve the above object, the decorative sheet of the present invention is obtained by subjecting a base sheet made of an olefin-based thermoplastic elastomer to a decorative treatment, wherein the base sheet is made of an inorganic material. Characterized in that it contains a system ultraviolet absorber.

In order to achieve the above object, a decorative sheet of the present invention comprises a base sheet made of an olefin-based thermoplastic elastomer, and at least one print layer formed on an upper layer of the base sheet. A surface protection sheet made of a transparent olefin-based thermoplastic elastomer formed on the upper layer of the printing layer, wherein at least the surface protection sheet contains an inorganic ultraviolet absorber.

The above decorative sheet of the present invention contains an inorganic ultraviolet absorber in the surface protective sheet or the base sheet, and is formed on the base sheet or the surface protective layer itself or a lower layer thereof. It has the function of suppressing and protecting the discoloration of the printed layer.The inorganic UV absorber does not decompose or elute during embossing in the manufacturing process or during long-term use as a product. The absorption capacity is not reduced, the roller for embossing is not contaminated, or the adhesion strength between the overcoat layer and the base sheet or the surface protection sheet is not reduced, and the heat resistance, durability and It has excellent weather resistance and can improve productivity and quality stability.

The above-mentioned decorative sheet of the present invention is preferably
The substrate sheet or the surface protective sheet containing the inorganic ultraviolet absorber further contains a hindered amine radical scavenger. In the case of using ultra-fine particles as the inorganic UV absorber, the activity of the particle surface is high, so that a strong catalytic action may occur or a phenomenon may occur in which the particles are re-agglomerated and difficult to disperse. By containing the agent, the above phenomenon can be suppressed, and the effect of the present invention can be effectively enjoyed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical embodiment of a decorative sheet according to the present invention will be described below with reference to the drawings.
FIG. 1 is a sectional view of one embodiment of the decorative sheet of the present invention. Here, the decorative sheet 1 of the present embodiment has a pattern printing layer 13b formed on the back surface of a base sheet 11 made of a transparent olefin-based thermoplastic elastomer. An inorganic ultraviolet absorber 19 is added to the base sheet 11. The ultraviolet absorber 19 absorbs and blocks ultraviolet rays that reach the base sheet 11 itself and the pattern printing layer 13b therebelow, so that the discoloration, peeling, strength reduction,
Prevents cracks and the like.

FIG. 2 is a sectional view of a decorative sheet according to another embodiment of the present invention. The decorative sheet 1 of the present embodiment is a doubling (two-layer laminated) type, is made of an olefin-based thermoplastic elastomer, and is made opaque (visible light absorbing) by adding a coloring agent 14 such as a pigment. Base material 11
And a transparent (visible light transmitting) surface protection sheet 16 made of an olefin-based thermoplastic elastomer.
A printing layer 13 composed of a primer layer 12, a solid printing layer 13a, and a picture printing layer 13b, and an adhesive layer 15 are formed by laminating between the sheet substrate 11 and the surface protection sheet 16. The back primer layer 10 is formed on the surface of the sheet substrate 11 opposite to the surface protection sheet 16 by lamination. The surface of the surface protection sheet 16 on the side opposite to the sheet substrate 11 is formed by embossing or the like.
a is formed, the surface of the surface protection sheet 16 has a pattern with an uneven shape, and the coloring ink 18 is embedded in the concave portion 16a by a wiping method. Further, an overcoat layer 17 is further formed thereon. Although illustration is omitted, as an embodiment of the decorative sheet of the present invention, in addition to the above, the base sheet alone or a laminate of the base sheet and the surface protection sheet is formed, and at least the outermost surface of these constituent sheets is provided. Any embodiment may be used as long as the sheet contains an inorganic ultraviolet absorber. Then, the layer itself containing the inorganic ultraviolet absorber or the layer located thereunder is protected from the influence of ultraviolet rays.

In each of the above embodiments, the sheet substrate 1
1 and the surface protection sheet 16 are obtained by processing an olefin-based thermoplastic elastomer into a sheet. Here, as the olefin-based thermoplastic elastomer, for example, (1) those described in Japanese Patent Publication No. 53-34210, for example, polyethylene, ethylene-propylene copolymer, ethylene-butene-1 copolymer, polypropylene ,
Propylene / butene-1 copolymer, polybutene-1, butene-1 / propylene / ethylene / 3 terpolymer, butene-1 / hexene-1 / octene-1 / 3 terpolymer,
A mixture of a hard segment of a crystalline polyolefin such as polymethylpentene and a soft segment of a rubber obtained by partially cross-linking a rubber such as various monoolefin rubbers, and (2) an olefin system described in JP-A-6-16832. Thermoplastic elastomer, (3) Tokiko 6-2
Patent No. 3278 discloses a polypropylene-based olefinic heat obtained by mixing isotactic polypropylene as a hard segment, atactic polypropylene as a soft segment, and mixing the hard segment and the soft segment at a weight ratio of 10:90 to 90:10. (4) As described in JP-A-54-60370 and JP-A-55-111226, fumaric acid, itaconic acid, acrylic acid and maleic acid are added to the above-mentioned olefinic thermoplastic elastomer. 10 ^-4 to 10% by weight, preferably 10 ^{-3 to} 5% by weight of a compound having a polar functional group such as a carboxyl group or a hydroxyl group such as an acid anhydride.
Graft polymerized, (5) One layer of polyethylene, α and β such as ethylene and acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, maleic acid, fumaric acid, etc.
-Extrusion lamination of a copolymer of an unsaturated carboxylic acid copolymer or a coextruded molten web having another layer of a metal neutralized product on a substrate, (6) JP-A-5-77371, Ethylene-propylene-butene terpolymer copolymer olefin-based thermoplastic elastomers described in, for example, Japanese Unexamined Patent Publication No. Hei 9-111055, such as a random copolymer of propylene having a propylene content of 90% by weight or more with ethylene or / and butene. To 100 parts by weight of the polyolefin resin of the formula (I):

[0016]

Embedded image

0.1 to 0.50 parts by weight of a transparent nucleating agent mainly containing an aryl phosphate compound represented by the formula:
And an aliphatic amide having 12 to 22 carbon atoms 0.003 to 0.
A polyolefin composition obtained by melt-kneading 3 parts by weight (butene may be any of 1-butene, 2-butene, and isobutylene, and particularly,
Butene is preferred. ), (7) an amorphous polyolefin having a propylene content of 50% by weight or more
A resin composition containing 0% by weight and 80 to 0% by weight of a crystalline polypropylene can be used, and a laminate of the above-mentioned olefin-based thermoplastic elastomer can also be used.

As the olefin-based thermoplastic elastomer, the following can be particularly preferably used. (1) An olefin-based thermoplastic elastomer comprising a blend of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment), and a blend of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment) Things (Tokuhei 6-2327)
No. 8). (2) Ethylene-propylene-butene terpolymer thermoplastic elastomer (JP-A-5-77371,
See JP-A-9-11055). (3) Polypropylene-based thermoplastic elastomer having isotactic polypropylene as a hard segment and atactic polypropylene as a soft segment described in Japanese Patent Publication No. Hei 6-23278, and acrylic acid, An olefin-based thermoplastic elastomer obtained by graft-polymerizing a compound having a polar functional group such as a carboxyl group or a hydroxyl group such as methacrylic acid, ethacrylic acid, itaconic acid, maleic acid, fumaric acid, and an acid anhydride thereof. An inorganic filler may be added to the olefin-based thermoplastic elastomer, if necessary, for the purpose of improving its creep deformation resistance and easy adhesion. Generally, the surface protective sheet 16 is not added, or is added as little as possible to ensure transparency. On the other hand, in the case of the substrate sheet in the configuration of FIG. 2, since transparency is generally unnecessary, it is preferable to add a necessary and sufficient amount of an inorganic filler for the above-mentioned property modification. As the inorganic filler, calcium carbonate, barium sulfate, clay, talc and the like are added in an amount of about 5 to 30% by weight.

The thickness of the base sheet or surface protective sheet made of the above-mentioned olefinic thermoplastic elastomer is, for example, about 50 to 200 μm, and any of a stretched sheet and an unstretched sheet can be used. The unstretched sheet is better in terms of formability at the time.

FIG. 2 in which the surface protection sheet 16 exists.
In the case of such a configuration, in order to suppress the fading of the print layer provided below the surface protection sheet 16 as a decorative treatment and to protect the print layer, an inorganic ultraviolet absorber must be contained in the surface protection sheet 16 without fail. contains. Then, in this case, the inorganic ultraviolet absorber in the base sheet is not essential, and only the ultraviolet absorbing action in the surface protection sheet is sufficient,
The addition of the inorganic ultraviolet absorber to the base sheet 11 may be omitted. In the case of the configuration as shown in FIG.
Since 1 is the outermost surface, it is essential to add an inorganic ultraviolet absorber to the base sheet.

Examples of the inorganic ultraviolet absorber include (1) a content of TiO ₂ having a rutile type structure of 9
0% or more, spherical or spindle-shaped ultrafine titanium oxide particles having a primary particle diameter of 0.02 to 0.05 μm, (2) Fe ₂ O
₃ Content is 99.5% or more and average particle size is 0.1 μm
(3) CeO ₂ content of 65 ±
3%, ultrafine cerium oxide having a primary particle diameter of 0.008 μm; (4) ultrafine zinc oxide having a ZnO content of 99% or more and a primary particle diameter of 0.005 to 0.04 μm;
(5) A flake having an average particle diameter of 0.1 to 50 μm, which is coated with a core pigment such as talc, mica, silica or the like with SiO ₂ (content: 18%) and CeO ₂ (content: 24%). Silica-cerium oxide-coated pigments in the form of particles or aggregates can be used.

When compared with the same weight, the above-mentioned ultrafine UV absorber has a larger number of particles than a particle having a larger particle size, so that the probability of hitting each particle with UV rays increases, Performance becomes higher. Further, when kneaded into the olefin-based thermoplastic elastomer of the surface protection sheet 16, transparency can be ensured, and the influence on the decorative layer such as a printing layer formed below can be cut off.

However, on the other hand, the ultrafine-particled ultraviolet absorber has a high activity on the surface of the particles, so that a strong catalytic action may occur, or a phenomenon may occur in which the ultraviolet absorber hardly disperses due to reaggregation. In order to suppress this phenomenon, the olefin-based thermoplastic elastomer of the surface protection sheet 16 has a
(2,2,6,6-tetramethyl-4-piperidinyl)
It is preferable to add a radical scavenger such as a hindered amine radical scavenger such as sebacate and bis- (N-methyl-2,2,6,6-tetramethyl-4-piperidinyl) sebacate and a piperidinyl radical scavenger.
More preferably, a hindered amine radical scavenger is added.

Further, it is preferable that the surface of the ultrafine particles of the inorganic ultraviolet absorber as described above is surface-treated with Al ₂ O ₃ or SiO ₂ or the like before use.

The decoration treatment includes formation of a printing layer, formation of a metal thin film, kneading of a coloring agent such as a pigment into a sheet, and formation of an uneven pattern.

The printing layer 13 employs any one of the solid printing layer 13a alone, the pattern printing layer 13b only, and the pattern printing layer 13b formed on the surface of the solid printing layer 13a. The picture printing layer 13b can be formed by printing ink or paint. As the ink or paint, those used in ordinary printing can be used. As a binder of the ink, for example,
Chlorinated polyethylene, chlorinated polyolefin resin such as chlorinated polypropylene, polyester resin, urethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer,
Cellulose-based resins and the like can be used. In addition, the above materials can be used alone or in combination of two or more.

Examples of the colorant (pigment) for the above-mentioned ink or paint include titanium white, zinc white, red petals,
Inorganic pigments such as vermilion, ultramarine blue, cobalt blue, titanium yellow, carbon black and the like, and organic pigments (including dyes such as isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, indathrene blue RS, anin phosphorus black, etc. ),aluminum,
Metal pigment consisting of foil powder such as brass, pearl luster consisting of foil powder such as titanium dioxide coated mica and basic lead carbonate
Pigments and the like can be used. Further, two or more of the above coloring agents may be added and used. The ink or paint may be transparent (transmitting visible light) or opaque (concealing or absorbing visible light).

As a method of providing the pattern printing layer 13b with the above ink or paint, a known printing method such as gravure printing, offset printing, silk screen printing, transfer printing from a transfer sheet, or the like can be used. As the picture pattern formed on the picture print layer 13b, a wood grain pattern,
Various patterns can be formed, such as stone patterns, cloth patterns, squeezed patterns, geometric figures, characters or symbols, and solid on the entire surface. Further, the above-mentioned patterns can be formed in combination.

Further, among the above inks or paints,
The solid printing layer 13a can also be formed by printing as a solid on the entire surface by using the above-described printing method using an opaque (concealing property, visible light absorbing) ink or paint. Solid printing layer 1
When both 3a and the pattern printing layer 13b are provided, the solid printing layer 13a is provided below the pattern printing layer 13b (on the sheet substrate 11 side) as shown in FIG.

It is possible to provide the printing layer 13 directly on the sheet substrate 11 made of an olefin-based thermoplastic elastomer, or to apply an adhesive layer 15 to the sheet substrate 11. When it is necessary to increase the adhesive strength, the primer layer 12 (front surface) and the back primer layer 10 (back surface) are formed on one or both of the front and back surfaces of the sheet substrate 11, or corona discharge is performed. It is preferable to perform an easy adhesion treatment such as a treatment, a plasma treatment, and an ozone treatment.

The above-mentioned primer layer 12 and back primer layer 10 (the primer layer is also called an anchor layer)
For example, acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin, urethane resin, chlorinated polypropylene, and chlorinated polyethylene can be used. Particularly, chlorinated polypropylene or urethane resin is preferable.

Examples of the above acrylic resin include poly (meth) acrylate, poly (ethyl) acrylate, poly (meth) acrylate, and poly (meth) acrylate.
Butyl acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, ethyl (meth) acrylate-butyl (meth) acrylate copolymer, ethylene-
An acrylic resin comprising a homo- or copolymer containing a (meth) acrylate such as a methyl (meth) acrylate copolymer or a styrene-methyl (meth) acrylate copolymer can be used. Here, (meth) acryl means acryl or methacryl, and the same applies hereinafter.

The urethane resin (polyurethane) is a polyurethane having a polyol (polyhydric alcohol) as a main component and an isocyanate as a cross-linking agent (curing agent). The polyol includes two or more hydroxyl groups in a molecule. For example, polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, polycarbonate polyol and the like can be used. On the other hand, as the isocyanate, a polyvalent isocyanate having two or more isocyanate groups in a molecule is used,
For example, aromatic isocyanates such as 2,4 tolylene diisocyanate, xylene diisocyanate, and 4,4 diphenylmethane diisocyanate, or hexamethylene diisocyanate, isophorone diisocyanate,
Aliphatic (or cycloaliphatic) isocyanates such as hydrogenated tolylene diisocyanate can be used. Alternatively, adducts or multimers of these isocyanates can also be used. For example, an adduct of tolylene diisocyanate and a trimer of tolylene diisocyanate can be mentioned.

In the decorative sheet 1 shown in FIG. 2, the surface protection sheet 16 having a visible light transmitting property is used.
In addition to the method of providing the print layer 13 on the surface of the substrate sheet 11 side of No. 6, a decoration process is further performed. That is, the sheet base material 11 is colored by adding a coloring agent 16 such as a pigment or a dye, and an uneven pattern is formed on the surface of the surface protection sheet 16 by embossing (hot pressing) or hairline processing. Be done. And the surface protection sheet 16
An inorganic ultraviolet absorber 19 is contained only in the inside.

When the sheet base material 11 or the surface protection sheet 16 is colored by adding a coloring agent 14 such as a pigment, the coloring agent may be, for example, titanium white, zinc white, red iron oxide,
Inorganic pigments such as vermilion, ultramarine blue, cobalt blue, titanium yellow, carbon black and the like, and organic pigments (including dyes such as isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, indathrene blue RS, anin phosphorus black, etc. ),aluminum,
Metal pigment consisting of foil powder such as brass, pearl luster consisting of foil powder such as titanium dioxide coated mica and basic lead carbonate
Pigments and the like can be used. Further, two or more of the above coloring agents may be added and used. Sheet base material 11
May be transparent (visible light transmitting) or opaque (concealing or visible light absorbing), but is usually opaque. In particular, in the case of a surface protection sheet, a lower printing layer,
The colorant 14 and the like in the base sheet are transparently colored so that they can be seen through.

The sheet substrate 1 of the surface protection sheet 16
As a method of forming the concave portion 16a so that the surface on the side opposite to 1 has an uneven pattern (irregular pattern), for example,
The surface protection sheet 16 made of an olefin-based thermoplastic elastomer is softened by heating, pressed and shaped by an embossed plate,
It can be formed by cooling and fixing. In this case, a known single-wafer or rotary embossing machine can be used. As the pattern formed by the uneven shape, for example, a pattern such as a wood grain conduit groove, a stone plate surface unevenness (such as a granite cleavage surface), a cloth surface texture, a satin finish, a grain, a hairline, and a linear groove can be formed. Further, the above patterns can be formed in combination. If necessary, the inside of the concave portion 16a can be filled with the coloring ink 18 by a known wiping method. As the wiping colored ink 18, an ink that can be used for the printing layer 14 described above can be used.

It is preferable to provide an overcoat layer 17 made of a crosslinkable resin on the surface of the surface protection sheet 16. FIG.
In the above, the upper coating 17 is provided only on the convex portions of the concavo-convex pattern, but may be formed over the entire surface including the concave portions and the convex portions. Alternatively, the overcoat layer 17 may be formed from a coating composition containing the crosslinkable resin as a binder and spherical particles having higher hardness than the crosslinkable resin. At the time of coating, it is preferable that the coating surface of the sheet substrate 11 be subjected to the above-mentioned easy adhesion treatment in advance in terms of improving the adhesiveness between the overcoat layer 17 and the surface protection sheet 16 and further improving the abrasion resistance.

Examples of the above-mentioned crosslinkable resin (or a binder composed of a crosslinkable resin) include, for example, an ionizing radiation-curable resin or a thermosetting resin (including a room temperature-curable resin and a two-component reaction-curable resin). A resin used as a crosslinkable resin of a known decorative material can be used.

As the above-mentioned ionizing radiation-curable resin, for example, a prepolymer, oligomer, and / or monomer having a polymerizable unsaturated bond such as a (meth) acryloyl group, a thiol group, or an epoxy group in the molecule may be used. A mixed composition curable by ionizing radiation is used. Here, the ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum that can polymerize or crosslink a molecule, and usually, an ultraviolet ray or an electron beam is used.

Examples of the above prepolymers and oligomers include unsaturated polyesters of condensates of unsaturated dicarboxylic acids and polyhydric alcohols, polyester (meth) acrylates, polyether (meth) acrylates, polyol (meth) acrylates, (Meth) acrylates such as melamine (meth) acrylate, and cationic polymerization type epoxy compounds can be used.

Examples of the above monomers include styrene monomers such as styrene and α-methylstyrene, methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methoxyethyl (meth) acrylate, and methoxyethyl (meth) acrylate. (Meth) acrylates such as butoxyethyl acrylate, butyl (meth) acrylate, methoxybutyl (meth) acrylate, and phenyl (meth) acrylate; 2- (N, N-diethylamino) (meth) acrylate ) Ethyl, (meth) acrylic acid-2- (N, N-dibenzylamino) methyl, (meth) acrylic acid-2-
Substituted amino alcohol esters of unsaturated carboxylic acids such as (N, N-diethylamino) propyl, unsaturated carboxylic acid amides such as acrylamide and methacrylamide, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate; Polyfunctional such as neopentyl glycol di (meth) acrylate, 1,6 hexanediol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate Compounds and / or polythiol compounds having two or more thiol groups in the molecule, such as trimethylolpropane trimethyl glycolate, trimethylolpropane trithiopropylate, pen Such as pentaerythritol tetra thio glycol may be employed.

When irradiating an ultraviolet ray to cure the ionizing radiation-curable resin having the above composition,
As a photopolymerization initiator, for example, acetophenones, benzophenones, Michler benzoyl benzoate, α-
Aminoxime esters, tetramethylthiuram monosulfide, thioxanthones, aromatic diazonium salts,
Aromatic sulfonium salts and metallocenes can be used, and n-butylamine, triethylamine, tri-n-butylphosphine and the like are further mixed as a photopolymerization accelerator (sensitizer) by about 0.5 to 10% by weight. Can be used.

Examples of the above-mentioned thermosetting resin include phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, and urethane resin (including two-component curable urethane). , An epoxy resin, an amino alkyd resin, a melamine-urea co-condensation resin, a silicon resin, a polysiloxane resin, and the like. In addition, a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, and the like can be added to the above-described resin as needed. As the above curing agent,
Usually, isocyanates or organic sulfonates are good for polyester resins and polyurethane resins, amines are good for epoxy resins, and peroxides such as methyl ethyl ketone peroxide and radical initiators such as azoisobutyl nitrile are good for unsaturated polyesters. Used.

As the above-mentioned isocyanate, divalent or higher aliphatic or aromatic isocyanate can be used, and aliphatic (or alicyclic) isocyanate is desirable from the viewpoint of weather resistance in order to prevent thermal discoloration. , Hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and the like.

As the two-part curable urethane resin,
For example, a first compound composed of a polyol compound (as described above) having an average of two or more hydroxyl groups in its molecular structure.
A mixture of a liquid and a second liquid composed of a polyisocyanate compound (as described above) such that the equivalent ratio of hydroxyl groups to isocyanate groups is 0.7 to 1.5 can be used.

Examples of the above epoxy resin include an epoxy resin having an average of two or more epoxy groups in its molecular structure and a monoamine or polyamine having three or more active hydrogens which react with the epoxy group in one molecule. And those prepared so that the ratio of the epoxy equivalent of the epoxy resin to the active hydrogen equivalent of the monoamine or polyamine is 0.7 to 1.5.

The spherical particles having a hardness higher than that of the above-mentioned crosslinkable resin include a closed spherical surface having a smooth surface such as a true sphere, an elliptical sphere obtained by flattening a sphere, or a shape close to the true sphere or ellipsoid sphere. It only needs to be surrounded by. A spherical particle having no protrusions or corners on the surface of the spherical particle and having no so-called cutting edge is preferred. Spherical particles greatly improve the abrasion resistance of the overcoat layer itself, compared to irregular shaped particles of the same shape, and do not require processing of the coating equipment. There is a feature that the object is not worn and the transparency of the coating film is also increased. This effect is particularly large when there is no cutting edge.

The amount of the spherical particles contained in the overcoat layer 17 is preferably about 5 to 20 parts by weight based on 100 parts by weight of the binder component composed of the crosslinked resin after curing. When the addition amount of the spherical particles is small, the effect of the addition of the spherical particles such as improvement of the abrasion resistance may not be sufficiently exerted.On the other hand, when the addition amount of the spherical particles is too large, the binder of the crosslinkable resin may be insufficient. However, the effects are impaired, and the flexibility of the coating film may be reduced, and the workability of the coating composition may be reduced.

The average particle diameter of the spherical particles is 1
Those having a thickness of from 50 μm to 50 μm are preferred. If the particle diameter of the spherical particles is too small, the overcoat layer 17 may become opaque, and the abrasion resistance decreases. On the other hand, if it is too large, the surface smoothness of the overcoat layer 17 and the possibility of a coating film may be reduced, and it is difficult to apply uniformly at the time of coating.

As the material of the above-mentioned spherical particles, for example, inorganic particles such as α-alumina, silica, chromium oxide, iron oxide and diamond, and organic resin particles such as synthetic resin beads such as cross-linked acrylic resin can be used. Can be. Examples of the above α-alumina include fused alumina, Bayer method alumina, and the like, and inorganic particles other than the above, such as zirconia, titania, or a eutectic mixture of these with fused alumina, Bayer method alumina, etc. it can. As a method of making the shape of these inorganic particles into a sphere, a method in which a pulverized amorphous inorganic compound is put into a high-temperature furnace having a melting point or higher to be melted, and made into a sphere using surface tension, A method in which a compound melted at a high temperature equal to or higher than the melting point is blown out into a mist to form a sphere can be used.

As the above-mentioned spherical particles, spherical α-alumina is particularly preferable because it has a very high hardness and a large effect on abrasion resistance and a spherical particle can be obtained relatively easily. Spherical α-alumina is disclosed in
As described in JP-A-55269, a mineralizer or crystallization agent such as alumina hydrate, a halogen compound or a boron compound is added in a small amount to a pulverized product of fused alumina or sintered alumina. By treating at a temperature of 2 hours or more, the cutting edge in alumina is reduced, and at the same time, a spherical shape can be obtained. Such spherical alumina is available from Showa Denko KK as "Spherical Alumina AS-1".
0, AS-20, AS-30, AS-40, AS-5
Those having various average particle sizes as "0" are commercially available.

The above spherical particles can be subjected to a surface treatment. For example, dispersibility is improved by treating with a fatty acid such as stearic acid. In addition, by treating the surface with a silane coupling agent, it is possible to improve the adhesiveness with a crosslinkable resin used as a binder and the dispersibility of particles in a coating composition.

The decorative sheet 1 of the present embodiment is made of a wood-based board such as a veneer, a plywood, a particle board, a wood fiber board, a ceramic base such as glass and ceramics, and a non-ceramic ceramic-based such as calcium silicate and cement. Base material, iron, copper,
It can be used by being attached to a metal substrate such as aluminum. As the shape of the substrate, various shapes such as a sheet (foil or film), a plate, and a three-dimensional shape are possible. At the time of sticking, it is possible to adhere using an ordinary adhesive, and as the adhesive, for example, a heat-sensitive adhesive, a solvent-activated adhesive, or an ionizing radiation-curable adhesive is selected according to the application. A urethane-based resin, in particular, a two-component curable urethane resin can be preferably used. As the ionizing radiation-curable adhesive or the two-component curable urethane resin, an ionizing radiation-curable adhesive or a two-component curable urethane resin that can be used for the crosslinkable resin of the above-mentioned overcoat layer 17 may be used. it can.

The decorative sheet of the present embodiment described above contains an inorganic ultraviolet absorber in the surface protective sheet and has a function of suppressing and fading the printed layer on which the lower layer is formed. Inorganic UV absorbers do not decompose or leach out during embossing in the manufacturing process or during long-term use as a product, so their UV absorbing ability is reduced or the embossing roller is contaminated. It is possible to improve heat resistance, durability and weather resistance, and to improve productivity and quality stability, without reducing the adhesive strength with the overcoat layer.

[0055] Corona discharge treatment on one surface Example (output 6 kw, processing speed 30
m / min), and then an olefin-based thermoplastic elastomer sheet (high-density polyethylene 6) having a back primer layer (comprising polyester polyol and tolylene diisocyanate and adding silica particles at 25% by weight)
It consists of a mixture of 0 parts by weight, 30 parts by weight of styrene-butadiene rubber and 10 parts by weight of calcium carbonate, and is colored yellow-brown by adding a total of 5 parts by weight of pigments (titanium white, carbon black and graphite). A film substrate having a thickness of 80 μm) was subjected to a corona discharge treatment (output: 6 kW, treatment speed: 30 m / min) on the side opposite to the back primer layer, and a primer layer (composed of polyester polyol and hexamethylene diisocyanate) was applied to the entire surface. The upper layer is solid printed on the entire surface with an ink for a solid printing layer (binder: acrylic polyol to which 8% by weight of hexamethylene diisocyanate is added, pigment: a mixture of titanium white, red iron oxide and graphite). To form a solid printing layer that has been concealed and colored, and an ink for a picture printing layer (binder: 8: 2 weight ratio mixture of acrylic resin and vinyl chloride-vinyl acetate copolymer; ), A wood grain pattern was printed by a gravure printing method. An adhesive layer (a mixture of acrylic polyol and hexamethylene diisocyanate, an application amount of 16 g / m ² ) was provided thereon, and an olefin-based thermoplastic elastomer sheet (80 parts by weight of an isotactic polypropylene hard segment and an atactic A mixture with 20 parts by weight of a soft segment of polypropylene,
In this mixture, 3% by weight of an inorganic ultraviolet absorber (ultrafine titanium oxide) and 0.5% by weight of a hindered amine radical scavenger are added. (Thickness: 80 μm). The laminated sheet obtained as described above was heated to 140 ° C., and an embossed plate was pressed and formed on the surface of the surface protection sheet to form an embossed surface having a wood grain conduit pattern. After performing corona discharge treatment on the upper layer,
The inside of the recess formed by embossing is filled with a coloring ink (binder: a mixture of acrylic polyol and hexamethylene diisocyanate, pigment: red iron oxide and carbon black) by a wiping method, and an overcoat layer (acrylic polyol and hexamethylene diisocyanate) is filled. 0.2% by weight of ultrafine cerium oxide and 0.2% by weight of a hindered amine radical scavenger were added to the mixture to a thickness of 3 μm to obtain a desired decorative sheet.

The decorative sheet formed as described above is
Since the ultraviolet absorber does not elute during thermal processing such as embossing, it does not adhere to the embossed plate, and the cleaning work of the embossed plate is simplified, and the time until the wiping process and the formation of the overcoat layer after embossing is performed. The adhesion strength did not decrease due to the fluctuation, and the productivity and quality stability were improved.

In addition, W.P. under the condition of (black panel temperature: 63 ° C., rain time: 120 minutes, rain (water spray) 18 minutes). O. After 3000 hours in the M test, the adhesion strength between the layers of the laminate constituting the decorative sheet is hardly changed (a delamination strength of 1.5 kg / inch width or more is maintained, and the discoloration / fading is conspicuous visually).・ Whitening ・
There was no change in appearance such as cracks), and the weather resistance was improved more than the conventional decorative sheet.

The present invention is not limited to the above embodiment. For example, a concave portion on the surface due to a primer layer, a concealing layer and embossing may be formed as necessary,
It can be omitted. Further, each of the above-described layers and the sheet substrate may have a single-layer structure or a multilayer structure.
In addition, various changes can be made without departing from the spirit of the present invention.

[0059]

According to the present invention, the surface protective sheet contains an inorganic ultraviolet absorber and has a function of suppressing and fading the discoloration of the print layer formed below.
Inorganic UV absorbers do not decompose or leach during embossing in the manufacturing process or during long-term use as a product, so UV absorbing capacity is reduced, or rollers for embossing are contaminated, Alternatively, the adhesive strength with the overcoat layer does not decrease, the heat resistance, the durability and the weather resistance are excellent, and the productivity and the quality stability can be improved.

[Brief description of the drawings]

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

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Decorative sheet, 10 ... Back primer layer, 11 ... Base sheet, 12 ... Primer layer, 13a ... Solid printing layer,
13b: picture printing layer, 13: printing layer, 14: colorant, 1
5: adhesive layer, 16: surface protection sheet, 16a: embossed concave portion, 17: overcoat layer, 18: colored ink, 19: inorganic ultraviolet absorber.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09K 15/30 C09K 15/30 E04F 13/00 E04F 13/00 B

Claims (3)

[Claims] 1. A decorative sheet comprising a base sheet made of an olefin-based thermoplastic elastomer, which is subjected to a decoration treatment, and wherein the base sheet contains an inorganic ultraviolet absorber. 2. A base sheet made of an olefin-based thermoplastic elastomer, at least one print layer formed on the base sheet, and a transparent olefin-based thermoplastic elastomer formed on the print layer. A decorative sheet comprising: a surface protective sheet comprising: an inorganic ultraviolet absorber at least in the surface protective sheet. 3. The decorative sheet according to claim 1, wherein the base sheet or the surface protective sheet containing the inorganic ultraviolet absorber further contains a hindered amine radical scavenger.