JP2009101603A - Facing sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a facing sheet having high UV absorbency and which can retain weatherability for a long period. <P>SOLUTION: The facing sheet 1 is characterized in that a transparent or translucent protective layer 16 is arranged on a base material sheet 11 and the protective layer 16 includes at least one kind of triazine-based UV absorbent having at least one maximum absorbing wavelength in a low wavelength range (250 to 300 nm), at least one kind of triazine-based UV absorbent having at least one maximum absorbing wavelength in a high wavelength range (300 to 370 nm), and at least one kind of hindered amine-based light stabilizer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to, for example, a decorative sheet used as a construction material such as an interior / exterior member for construction, a joinery, a frame material, a flooring material, or a surface material for home appliances, and mainly wood boards and inorganic boards. The present invention relates to a decorative sheet used when a decorative plate is produced by bonding to a metal plate or the like.

  A decorative sheet is used as a surface material for building interior / exterior members, joinery, frame materials, flooring materials, etc., or home appliances, and materials mainly composed of vinyl chloride resin are widely used. ing. However, the vinyl chloride resin has problems such as generation of chlorine gas at the time of incineration causing acid rain and dioxin and bleeding out of the added plasticizer. Therefore, a decorative sheet that does not use a vinyl chloride resin is desired from the viewpoint of environmental problems.

As a decorative sheet not using a vinyl chloride resin, a decorative sheet using a material such as an olefin-based resin is shown (for example, Patent Documents 1 to 3).
However, a decorative sheet using a general polyolefin sheet or a soft polyolefin sheet is inferior in surface scratch resistance and weather resistance compared to a decorative sheet using a vinyl chloride resin. In order to improve the surface scratch resistance, it is conceivable to use a resin material having high crystallinity and high isotacticity, but this method tends to deteriorate the weather resistance.

  Therefore, attempts have been made to provide a protective layer made of another resin on the surface of the polyolefin sheet of the decorative sheet to improve the surface gloss and improve the surface damage resistance. Moreover, as a method for improving weather resistance, a method in which a polyolefin sheet and a protective layer each contain a weathering agent such as an ultraviolet absorber is shown.

However, depending on the type of weathering agent, there are some which cannot function sufficiently as a weathering agent even if contained in a polyolefin sheet.
Therefore, it is also shown that a triazine-based ultraviolet absorber having a high effect of improving the weather resistance and a high effect of improving weather resistance is used although the compatibility with the resin is not so high (Patent Document 4).
JP-A-2-128843 JP-A-6-198831 JP 9-328562 A JP 2004-66525 A

However, in the method of Patent Document 4, even if a triazine ultraviolet absorber is used, although the ultraviolet absorption ability is high, the weather resistance may not be maintained for a long time.
Therefore, the present invention has an object of a decorative sheet that has high ultraviolet absorption ability and can maintain weather resistance for a long period of time.

The decorative sheet of the present invention is provided with a transparent or translucent protective layer on a base sheet, and the protective layer has a triazine type having at least one maximum absorption wavelength in a low wavelength region (250 to 300 nm). One or more ultraviolet absorbers, a triazine ultraviolet absorber having at least one maximum absorption wavelength in a high wavelength region (300 to 370 nm), and a hindered amine light stabilizer are contained.
In the decorative sheet of the present invention, it is preferable that the molecular weight of the triazine-based ultraviolet absorber having at least one maximum absorption wavelength in the low wavelength region (250 to 300 nm) is 490 to 650.
Moreover, it is preferable that the protective layer further contains at least one selected from the group consisting of an inorganic ultraviolet absorber made of a metal oxide and a benzotriazole ultraviolet absorber.

In the decorative sheet of the present invention, a transparent or translucent thermoplastic resin layer is provided between the base sheet and the protective layer, and a triazine-based ultraviolet absorber, metal oxide is provided on the thermoplastic resin layer. It is preferable that at least one selected from the group consisting of inorganic ultraviolet absorbers made of substances and benzotriazole ultraviolet absorbers and a hindered amine light stabilizer are contained.
Moreover, it is preferable that the said thermoplastic resin layer is provided on the said base material sheet through the adhesive resin layer. Moreover, it is preferable that the said thermoplastic resin layer contains polyolefin resin.
Moreover, it is preferable that the decorative sheet of this invention is provided with the pattern layer in the said base material sheet.

  The decorative sheet of the present invention has high ultraviolet absorption ability and can maintain weather resistance for a long period of time.

The decorative sheet of the present invention includes a triazine ultraviolet absorber having at least one maximum absorption wavelength in a low wavelength region (250 to 300 nm) and a triazine type having at least one maximum absorption wavelength in a high wavelength region (300 to 370 nm). A protective layer containing at least one ultraviolet absorber and at least one hindered amine light stabilizer is provided on the substrate sheet.
Hereinafter, an embodiment of the decorative sheet of the present invention will be described with reference to FIG.
As shown in FIG. 1, the decorative sheet 1 has a pattern layer 12, an adhesive layer 13, an adhesive resin layer 14, a thermoplastic resin layer 15, and a protective layer 16 sequentially laminated on a base sheet 11. In addition, a primer layer 17 is provided on the surface 11 a side of the base sheet 11.

(Substrate sheet)
Examples of the base sheet 11 include paper such as thin paper, titanium paper, and resin-impregnated paper; polyolefin resins such as polyethylene, polypropylene, and polyolefin-based thermoplastic elastomers, polystyrene, polycarbonate, polyester, polyamide, and ethylene-vinyl acetate copolymer. Sheet made of resin such as coalescence, polyvinyl alcohol, acrylic, or foam of these resins; ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene block copolymer Examples thereof include a polymer rubber, a styrene-butadiene-styrene block copolymer rubber, and a sheet made of rubber such as polyurethane.

In the base material sheet 11, in order to improve machinability, an organic component filler, an inorganic filler, etc. may contain.
Examples of the organic component filler include urethane crosslinked particles, acrylic crosslinked particles, melamine resin, and natural collagen. Examples of the inorganic filler include alumina, silica, silicon nitride, silicon carbide, glass beads, aluminum hydroxide, calcium carbonate and the like, which are component materials of general topcoat agents.
In addition, when the resin constituting the base sheet 11 has transparency, the base sheet 11 may contain a pigment or the like in order to provide the decorative sheet 1 with concealability.
However, the term “transparent” and “translucent” as used in the present invention means that the total light transmittance defined in JIS K7105 is 75% or more.

(Picture layer)
The pattern layer 12 is a layer that imparts design properties to the decorative sheet 1. Thereby, the designability of the decorative sheet 1 can be improved. In addition, the pattern layer 12 can prevent the base material on which the decorative sheet 1 is bonded from being visible from the protective layer 16 side.
As the form of the pattern layer 12, it is a layered pattern having a predetermined pattern shape, a solid pattern on the entire surface, or a combination of a pattern-shaped part and a solid-shaped part as appropriate. And the like.

Examples of the material of the picture layer 12 include printing ink. The printing ink is obtained by adding a colorant such as a pigment and a dye, an extender pigment, a solvent, and various additives into a binder.
Examples of the binder include nitrified cotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester and other modified resins, and modified products thereof. A binder may be used individually by 1 type and may use 2 or more types together. These may be water-based, solvent-based, or emulsion-based, and may be one-pack type or two-pack type using a curing agent.
Moreover, as a curing type, a binder that is cured by irradiation with active energy rays such as ultraviolet rays and electron beams, and a urethane-based binder that is isocyanate-cured can also be used. Among those cured by irradiation with active energy rays such as ultraviolet rays and electron beams, those using electron beams are preferably used because they are superior in curing in the thickness direction compared to those using ultraviolet rays.
Examples of the pigment include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, mica and the like.
In selecting a material for forming the pattern layer 12, it is preferable to sufficiently consider the adhesiveness with a layer adjacent to the pattern layer 12.

  Further, the ink for forming the pattern layer 12 may be the same in the material structure when it is formed in a solid shape or in a pattern shape, but it is concealed by forming a solid thin film. When the pattern layer 12 having the property is used, an opaque pigment, a pigment such as titanium oxide or iron oxide may be contained. Moreover, in order to make it the pattern layer 12 which has concealability, you may use the fine powder which consists of metals, such as gold | metal | money, silver, copper, and aluminum. Among these, flaky aluminum can be preferably used.

  When the pattern layer 12 is formed in a solid shape mainly for concealing the base material bonded to the decorative sheet 1, the thickness is preferably about 2 to 10 μm. When the thickness is 2 μm or more, sufficient concealing property is easily obtained. Moreover, if thickness is 10 micrometers or less, it is easy to keep the cohesion force of the pattern layer 12 high.

  Examples of the method for providing the pattern layer 12 include gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, and ink jet printing. When the solid pattern layer 12 is provided, it is preferable to use a coating method such as a comma coater, a knife coater, or a lip coater, or a metal vapor deposition method or a sputtering method.

(Adhesive layer)
The adhesive layer 13 plays a role of increasing the adhesive strength between the pattern layer 12 and the adhesive resin layer 14.
The material of the adhesive layer 13 may be any material as long as sufficient adhesive strength can be obtained, and a known adhesive material can be used. Examples thereof include acrylic, polyester, polyurethane, and epoxy adhesive materials. Among these, a two-component curable polyurethane adhesive material having high coating cohesive strength is preferable.

The coating method of the adhesive layer 13 may be appropriately selected depending on the coating liquid viscosity of the adhesive material, and it is preferable to use a gravure plate dry coating method from the viewpoint that the coating amount can generally be kept low. The coating amount may be appropriately determined in consideration of adhesive strength, cost, etc., and is preferably as low as possible.
Depending on the material of the adhesive resin layer 14, the adhesive layer 13, the adhesive resin layer 14, and the thermoplastic resin layer 15 are integrally formed by extrusion lamination, dry lamination, or the like according to the material of the adhesive layer 13. It may be formed.

(Adhesive resin layer)
The adhesive resin layer 14 improves the adhesion between the base sheet 11 side and the protective layer 16 side of the decorative sheet 1 (in this embodiment, the adhesive layer 13 and the thermoplastic resin layer 15), and the strength of the decorative sheet 1 is increased. It is a layer that improves In particular, when a nonpolar resin such as polypropylene is used as the thermoplastic resin layer 15, since the adhesive strength between the adhesive layer 13 and the thermoplastic resin 15 is weak, the thermoplastic resin can be obtained by providing the adhesive resin layer 14. The layer 15 can be formed stably.
Examples of the material of the adhesive resin layer 14 include a material obtained by modifying a resin such as polypropylene, polyethylene, or acrylic with an acid.

The thickness of the adhesive resin layer 14 is preferably 2 to 20 μm. If the thickness is 2 μm or more, sufficient adhesive strength can be obtained. Moreover, if the thickness is 20 μm or less, the surface strength of the decorative sheet 1 is reduced due to the flexibility of the adhesive resin layer 14 being too high, or sufficient adhesive strength is obtained due to a decrease in cohesive force and heat resistance. It is easy to prevent it from happening.
The adhesive resin layer 14 is preferably laminated by coextrusion with the thermoplastic resin layer 15 from the viewpoint of adhesive strength.

(Thermoplastic resin layer)
The thermoplastic resin layer 15 plays a role of improving surface strength and weather resistance.
Examples of the resin material of the thermoplastic resin layer 15 include known polyolefin resins such as polyethylene, polypropylene, and polyolefin-based thermoplastic elastomers, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and the like. A thermoplastic resin is mentioned. Of these, polyolefin resins are preferred from the viewpoint of low environmental burden. Moreover, it is preferable that it is a polypropylene among polyolefin resin. Specific examples include a homopolymer which is a homopolymer of propylene, and a binary or ternary random polymer copolymer obtained by copolymerizing polypropylene and ethylene, butene or the like.

  In particular, when it is desired to impart a superior surface strength to the decorative sheet 1, it is preferable to use highly crystallized polypropylene. It should be noted that other resins can be added to the highly crystallized polypropylene. However, when it is desired to provide post-processing suitability such as bending, sufficient attention should be paid to the compatibility with the highly crystallized polypropylene resin. .

  In order to improve the weather resistance, the thermoplastic resin layer 15 appropriately contains an ultraviolet absorber and a hindered amine light stabilizer. Examples of the UV absorber include triazine UV absorbers, benzotriazole UV absorbers, and inorganic UV absorbers made of metal oxides. Only one of these ultraviolet absorbers may be used alone, or two or more of them may be used in combination.

  Examples of the triazine ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4-[( 2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [4-[(2- Hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4dimethylphenyl) -1,3,5-triazine, 2,4-bis (2,4-dimethyl) Phenyl) -6- (2-hydroxy-4-iso-octyloxyphenyl) -s-triazine, 2- [4,6-bis (2,4-dimethylphenyl) 1,3,5-triazin-2-yl ] -5 And octyloxy) phenol and the like, mixtures thereof, modified products, polymers, derivatives and the like. Only one type of triazine-based ultraviolet absorber may be used alone, or two or more types may be used in combination.

  It is preferable that content of a triazine type ultraviolet absorber is 0.1-1 mass part with respect to 100 mass parts of thermoplastic resins. If the content of the triazine-based ultraviolet absorber is 0.1 parts by mass or more, sufficient ultraviolet absorbing ability is easily obtained.

  Examples of the benzotriazole ultraviolet absorber include 2- (2H-benzotriazol-2-yl) -p-cresol and 2- (2H-benzotriazol-2-yl) -4-6-bis (1-methyl). -1-phenylethyl) phenol, 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol, 2- (2H-benzotriazol-yl)- 4,6-di-tert-pentylphenol, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol and the like, mixtures thereof, modified products, Examples thereof include polymers and derivatives. A benzotriazole type ultraviolet absorber may be used individually by 1 type, and may use 2 or more types together.

  It is preferable that content of a benzotriazole type ultraviolet absorber is 0.1-1.0 mass part with respect to 100 mass parts of thermoplastic resins. If the content of the benzotriazole-based ultraviolet absorber is 0.1 parts by mass or more, sufficient ultraviolet absorbing ability is easily obtained. Moreover, if content of a benzotriazole type ultraviolet absorber is 1.0 mass part or less, there exists a possibility that the adhesive strength with the other layer (for example, protective layer 16) adjacent to the thermoplastic resin layer 15 may fall too much. Few.

  Examples of inorganic ultraviolet absorbers made of metal oxides include semiconductors such as anatase-type titanium oxide ultrafine particles, rutile-type titanium oxide ultrafine particles, zinc oxide ultrafine particles, cerium oxide ultrafine particles, and mixtures thereof. The energy difference between the band gap of the electron band and the conduction band is equivalent to that in the ultraviolet region of radiation. Only one inorganic ultraviolet absorber made of a metal oxide may be used alone, or two or more may be used in combination.

An inorganic ultraviolet absorber made of a metal oxide is preferable because the smaller the primary particle size, the smaller the scattering and the transparency to the light in the visible light region. Further, when the primary particle size is increased, it becomes opaque with respect to light in the visible light region, but when the particle size approaches the wavelength in the ultraviolet light region, a scattering effect works and the ultraviolet shielding effect is improved.
From this, the primary particle size of the inorganic ultraviolet absorbent made of the metal oxide of the decorative sheet 1 is preferably 10 to 400 nm in view of transparency, weather resistance, ultraviolet absorbing ability and the like.

It is preferable that content of the inorganic type ultraviolet absorber which consists of metal oxides is 0.1-1 mass part with respect to 100 mass parts of thermoplastic resins. If the content of the inorganic ultraviolet absorber made of a metal oxide is 0.1 parts by mass or more, sufficient ultraviolet absorbing ability is easily obtained.
In addition, as for the total amount of the said ultraviolet absorber, it is more preferable that it is 1 mass part or less with respect to 100 mass parts of thermoplastic resins.

  Examples of the hindered amine light stabilizer include dimethyl succinate 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine, poly [{6- (1,1,3 , 3-Tetramethylbutyl) amino-1,3,5-triazine-2,4diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6 , 6-tetramethyl-4-piperidyl) imino}], N, N′-bis (3-aminopropyl) ethylenediamine · 2,4-bis [N-butyl-N- (1,2,2,6,6) -Pentamethyl-4piperidyl) amino] -6-chloro-1,3,5-triazine, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, 2- (3,5-di-t -Butyl-4-hydroxy Ndyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2 3,4-butanetetracarboxylate and the like. Only one type of hindered amine light stabilizer may be used alone, or two or more types may be used in combination.

  The content of the hindered amine light stabilizer is preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the thermoplastic resin. If content of a hindered amine light stabilizer is 0.1 mass part or more, it will be easy to fully improve the weather resistance of the decorative sheet 1.

  In addition, the thermoplastic resin layer 15 may have an antioxidant, a heat stabilizer, if necessary, in addition to the ultraviolet absorber and the hindered amine light stabilizer, as long as the transparency or translucency is maintained. A flame retardant, a quencher, an antiblocking agent, a catalyst accelerator, a colorant, a light scattering agent for making translucent, a gloss adjusting agent, and the like may be contained.

Examples of the antioxidant include various antioxidants such as phenol, sulfur, and phosphorus. These antioxidants can be combined with other additives arbitrarily, but when they are contained in a large amount, they bleed out to the surface of the thermoplastic resin layer 15, and the colorant, ultraviolet absorber, light stability contained together. It is necessary to pay close attention to synergistic and antagonistic actions with agents.
As a heat stabilizer, heat stabilizers, such as a hindered phenol type, a sulfur type, and a fertilizer resin type, are mentioned, for example.
Examples of the flame retardant include aluminum hydroxide and magnesium hydroxide.
Examples of the quencher include Ni chelate type quenchers.
In addition to inorganic UV absorbers made of metal oxides, triazine UV absorbers, and benzotriazole UV absorbers, UV absorbers such as bezoate, benzophenone, salicylate, and cyanoacrylate are appropriately added. Also good.

  Further, in order to impart cutting properties to the thermoplastic resin layer 15 and improve various physical properties, a filler component may be further contained in addition to the resin and additives. Examples of the filler component include urethane cross-linked particles, acrylic cross-linked particles, melamine resins, organic component fillers such as natural collagen, and alumina, silica, silicon nitride, silicon carbide that are also used as component materials for general top coat agents. And inorganic fillers such as glass beads, aluminum hydroxide and calcium carbonate.

As a method for forming the thermoplastic resin 15, a known forming method can be used. For example, an extrusion method, a multilayer coextrusion method formed together with the adhesive resin layer 14, or the like can be applied.
The thickness of the thermoplastic resin layer 15 is preferably 30 to 200 μm. If the thickness of the thermoplastic resin layer 15 is 30 μm or more, the effect of improving the surface strength and weather resistance can be sufficiently obtained. Moreover, if the thickness of the thermoplastic resin layer 15 is 200 micrometers or less, the production efficiency of the decorative sheet 1 will become high and it will be excellent in economical efficiency.

(Protective layer)
The protective layer 16 is a layer provided for protecting the base sheet 11 and each layer from being deteriorated by ultraviolet rays, improving the stain resistance, and further adjusting the gloss of the surface.
The protective layer 16 is mainly composed of a crosslinked resin material, and is made of a protective layer forming material containing an ultraviolet absorber and a light stabilizer.
Examples of the resin include polyurethane, acrylic silicon, fluorine, epoxy, vinyl, polyester, melamine, aminoalkyd, and urea resin materials.
The form of the material for forming the protective layer may be any of aqueous, emulsion, solvent type, etc. The curing type may be a one-component type or a two-component type using a curing agent. Good. Among these, from the viewpoint of workability at the time of formation, cost, cohesive strength of the resin itself, and the like, the protective layer 16 mainly composed of polyurethane-based resin using isocyanate is preferable.

  Examples of the isocyanate include tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), metadiisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), methylhexane diisocyanate ( HTDI), methylcyclohexanone diisocyanate (HXDI), trimethylhexamethylene diisocyanate (TMDI) and the like. Among these, from the viewpoint of weather resistance, an isocyanate having a linear structure is preferable to an isocyanate having a double bond, and hexamethylene diisocyanate (HMDI) is particularly preferable.

  In order to further improve the surface hardness, a resin curable with active energy rays such as ultraviolet rays and electron beams may be used. In addition to using the above alone, a hybrid curing type using both a thermosetting type and a photocurable type may be effective in terms of surface strength, curing shrinkage, adhesion, and the like.

  In order to improve the weather resistance, the protective layer 16 includes a triazine-based ultraviolet absorber (hereinafter referred to as a low-wavelength region triazine-based ultraviolet absorber) having at least one maximum absorption wavelength in a low wavelength region (250 to 300 nm). , Containing at least one triazine-based ultraviolet absorber having at least one maximum absorption wavelength in the high-wavelength region (300 to 370 nm) (hereinafter referred to as a high-wavelength region triazine-based ultraviolet absorber) and one or more hindered amine-based light stabilizers Has been.

  Examples of the low wavelength region triazine-based ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 3-cyclohexyl- Propionic acid 2- [4- (4,6-diphenyl- [1,3,5] triazin-2-yl) -3-hydroxy-phenoxy] -ethyl ester, cyclohexane-1,2-dicarboxylic acid Bis- {2- [4- (4,6-diphenyl- [1,3,5] triazin-2-yl) -3-hydroxy-phenoxy] ethyl} ester, 2-ethyl-hexanoic acid 2- [ 4- (4,6-diphenyl- [1,3,5] triazin-2-yl) -3-hydroxy-phenoxy] -ethyl ester (molecular weight 512), octanoy Quad 2- [4- (4,6-diphenyl- [1,3,5] triazin-2-yl) -3-hydroxy-phenoxy] -ethyl ester (molecular weight 512), 2- [4-[(2- Hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine (molecular weight 647), 2- [4-[( 2-hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine (molecular weight 647), 2- [4 -[(2-hydroxy-3- (2'-ethyl) hexyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine (molecular weight 583), 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-iso-octyloxyphenyl) -1,3,5-triazine (molecular weight 509), etc., and mixtures thereof , Modified products, polymers, derivatives and the like. These may be used alone or in combination of two or more.

The content of the low wavelength region triazine-based ultraviolet absorber is preferably 0.1 to 10 parts by mass when the weight of the protective layer 16 is 100 parts by mass. When the content of the low wavelength region triazine-based ultraviolet absorber is 0.1 parts by mass or more, sufficient ultraviolet absorbing ability is easily obtained, and excellent weather resistance is easily obtained. When the content of the low wavelength region triazine-based ultraviolet absorber is 10 parts by mass or less, the compatibility with the resin constituting the protective layer 16 is improved, and the bleeding out of the low wavelength region triazine-based ultraviolet absorber can be suppressed. .
In addition, the low wavelength region triazine-based ultraviolet absorber has a molecular weight of more preferably 490 to 650, and particularly preferably 500 to 520, from the viewpoint of enhancing the compatibility with the resin.

  Examples of the high wavelength region triazine-based UV absorber include 2- (2hydroxy-4- [1-octyloxycarbonylethoxy] phenyl) -4,6-bis (4-phenylphenyl) -1,3,5- Triazine, 2,4,6-tris {2- (2-hydroxy-4- [1-octyloxycarbonylethoxy] phenyl)}-1,3,5-triazine, 2,4-bis (2-hydroxy-4) -Butyloxyphenyl) -6- (2,4-bis-butyloxyphenyl) -1,3,5-triazine and the like, and mixtures, modified products, polymers and derivatives thereof. These may be used alone or in combination of two or more.

  The content of the high wavelength region triazine-based ultraviolet absorber is preferably 0.1 to 10 parts by mass when the weight of the protective layer 16 is 100 parts by mass. When the content of the high wavelength region triazine-based ultraviolet absorber is 0.1 parts by mass or more, sufficient ultraviolet absorbing ability is easily obtained, and excellent weather resistance is easily obtained. When the content of the high wavelength region triazine-based ultraviolet absorber is 10 parts by mass or less, the compatibility with the resin constituting the protective layer 16 is improved, and the bleeding out of the high wavelength region triazine-based ultraviolet absorber is suppressed. .

  Examples of the hindered amine light stabilizer include bis (1,2,2,6,6-pentamethyl-4-piperidinyl)-[[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl]. Methyl] butyl malonate, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, methyl (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis-decanedioic acid bis [2,2,6,6-tetramethyl-1-octyloxy) -4-piperidinyl] ester, 2-4-bis [N-butyl-N- (1-cyclohexyloxy-2,2,6,6-) Tetramethylpiperidin-4-yl) amino] -6- (2-hydroxyethylamine) -1,3,5-triazine and the like, and mixtures, modified products, polymers and derivatives thereof. That. These may be used alone or in combination of two or more.

  The content of the hindered amine light stabilizer is preferably 0.1 to 20 parts by mass when the weight of the protective layer 16 is 100 parts by mass. If the content of the hindered amine light stabilizer is 0.1 parts by mass or more, sufficient weather resistance is easily obtained. Moreover, if content of a hindered amine light stabilizer is 20 mass parts or less, compatibility with resin which comprises the protective layer 16 will become favorable, and the bleed-out of a hindered amine light stabilizer will be suppressed.

  The protective layer 16 has at least one selected from the group consisting of inorganic ultraviolet absorbers made of metal oxides and benzotriazole ultraviolet absorbers in addition to the triazine ultraviolet absorbers and hindered amine stabilizers. Is further preferably contained. Thereby, the weather resistance of the decorative sheet 1 can be further improved.

  Examples of inorganic ultraviolet absorbers made of metal oxides include semiconductors such as anatase-type titanium oxide ultrafine particles, rutile-type titanium oxide ultrafine particles, zinc oxide ultrafine particles, cerium oxide ultrafine particles, and mixtures thereof. The energy difference between the band gap of the electron band and the conduction band is equivalent to that in the ultraviolet region of radiation.

The primary particle size of the inorganic ultraviolet absorbent made of a metal oxide may be appropriately set in consideration of transparency, weather resistance, ultraviolet absorbing ability, etc., and is preferably 10 to 400 nm.
The amount of the inorganic ultraviolet absorber made of a metal oxide is preferably 0.1 to 10 parts by mass when the weight of the protective layer 16 is 100 parts by mass.

Examples of the benzotriazole ultraviolet absorber include 2- (2H-benzotriazol-2-yl) -p-cresol and 2- (2H-benzotriazol-2-yl) -4-6-bis (1-methyl). -1-phenylethyl) phenol, 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol, 2- (2H-benzotriazol-yl)- 4,6-di-tert-pentylphenol, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol, 3- (2H-benzotriazole-2) -Yl) -5 (1,1-dimethylethyl) -4-hydroxy-, C7-9-alkyl ester, octyl-3- [3-tert-butyl-4-hydro Ci-5- (5-Chloro-2H-benzotriazol-2-yl) phenyl] propionate, 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazole) -2-yl) phenyl] propionate, 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy-, C7-9-alkyl ester, 2- (2H- Benzotriazol-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) phenol, β- [3- (2-H-benzotriazol-2-yl) -4-hydroxy-5-te t-butylphenyl] -propionic acid-poly (ethylene glycol) 300-ester, bis {β- [3- (2-H-benzotriazol-2-yl) -4-hydroxy-5-tert-butylphenyl ] -Propionic acid} -poly (ethylene glycol) 300-ester and the like, and mixtures, modified products, polymers, and derivatives thereof. These may be used alone or in combination of two or more.
The content of the benzotriazole ultraviolet absorber is preferably 0.1 to 10 parts by mass when the weight of the protective layer 16 is 100 parts by mass.
In addition, the total amount of the total ultraviolet absorber in the protective layer 16 is more preferably 10 parts by mass or less when the weight of the protective layer 16 is 100 parts by mass.

  Moreover, in order to provide various functions to the protective layer 16, you may add functional additives, such as an antibacterial agent, a fungicide, and a flame retardance. Further, an inorganic filler such as alumina, silica, silicon nitride, silicon carbide, glass beads or the like may be added for imparting design properties to the surface, adjusting gloss, and improving wear resistance.

  Examples of the flame retardant include aluminum hydroxide, magnesium hydroxide, and a Ni chelate system as a quencher. These can be contained in any combination. In addition to the above-mentioned triazine, benzotriazole, and inorganic ultraviolet absorbers composed of metal oxides, ultraviolet absorbers such as benzoate, benzophenone, salicylate, and cyanoacrylate are also used as the ultraviolet absorber. May be. Specific examples include benzophenone-based octabenzone, modified products, polymers, and derivatives thereof.

  Since the protective layer 16 is located on the outermost surface, it particularly affects the weather resistance of the decorative sheet 1. Therefore, the amount of these functional additives added depends on the solubility of the protective layer forming material (coating solution) in the resin and solvent, but the protective layer is also considered in consideration of the required physical properties and harmful effects caused by the addition of a large amount. It is preferable to set it as 0.1-10 mass parts with respect to 100 mass parts of solid content of a forming material.

  The method for forming the protective layer 16 may be selected in accordance with the properties, viscosity, coating amount, etc. of the protective layer forming material. For example, general coating such as gravure coating, micro gravure coating, comma coating, lip coating, etc. The method can be adopted. Further, an uneven embossed pattern may be applied to the protective layer 16 in order to improve design properties.

  The thickness of the protective layer 16 is preferably 1 to 20 μm. When the thickness of the protective layer 16 is 1 μm or more, various physical properties such as weather resistance are likely to be sufficiently improved. Moreover, if the film thickness of the protective layer 16 is 20 μm or less, the bending workability is improved.

  When the embossed pattern is applied to the protective layer 16, a method of embossing by heat pressure after laminating each layer by various methods, a method of embossing at the same time as forming the protective layer 16 by extrusion lamination by providing an uneven pattern on the cooling roll, etc. There is. In addition, there is a method in which the protective layer 16 subjected to simultaneous embossing at the time of extrusion, the base sheet 11 and each layer are bonded together by heat or dry lamination. Further, ink or resin may be embedded in the embossed recesses, and the ink or resin in the recesses may be transferred to improve design properties and weather resistance.

(Primer layer)
A primer layer 17 is provided on the surface 11 a side of the base sheet 11. Thereby, the adhesiveness of the decorative sheet 1 and the base material to be bonded can be improved.
The primer layer 17 is composed of a conventionally known easy-adhesive primer agent mainly composed of, for example, a urethane resin, an acrylic resin, an ethylene-vinyl acetate resin, a polyester resin, or the like. Further, by adding an inorganic fine powder such as silica to the primer layer 17 to roughen the surface, it becomes difficult for blocking to occur when the decorative sheet 1 is wound and stored, and makeup is achieved by the anchoring effect. Adhesiveness between the sheet 1 and the base material is improved.

The decorative sheet 1 of the present invention described above is excellent in ultraviolet absorbing ability and can maintain weather resistance for a long period of time.
The reason for this is that the UV absorber contained in the protective layer is a triazine-based UV absorber having at least one maximum absorption wavelength in the low wavelength region (250 to 300 nm) and a maximum absorption in the high wavelength region (300 to 370 nm). It is mentioned that a triazine ultraviolet absorber having at least one wavelength is used in combination. Since these ultraviolet absorbers can form a protective layer corresponding to almost the entire ultraviolet region, it is considered that the weather resistance can be maintained for a long time regardless of the material of the decorative sheet.

  Although triazine-based ultraviolet absorbers have excellent ultraviolet-absorbing ability, each triazine-based ultraviolet absorber has a specific maximum absorption wavelength. The decorative sheet is composed of various materials, and not only the deterioration wavelength differs depending on the decorative sheet, but also the deterioration wavelength is different in each layer. Therefore, the conventional method cannot sufficiently suppress the deterioration of all layers. It is thought that there was.

  The decorative sheet of the present invention is not limited to the one illustrated in FIG. For example, a decorative sheet having only the base sheet 11 and the protective layer 16 may be used. In addition, when the adhesive strength between the adhesive layer 13 and the thermoplastic resin layer 15 is high, a decorative sheet without the adhesive resin layer 14 may be provided.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following description.
[Example 1]
As the base material sheet 11, a base material sheet (thickness 120 μm) made of polyethylene was prepared. On the surface of the base sheet 11, a pattern layer 12 having a grain pattern is provided by a gravure printing method using a pattern ink (trade name: Lamister, manufactured by Toyo Ink Manufacturing Co., Ltd.), and a two-component curable urethane resin is formed thereon An adhesive layer 13 having a thickness of about 2 μm made of a system adhesive was provided (hereinafter referred to as a polyethylene base sheet).
Further, as a material for forming the thermoplastic resin layer 15, 2- [5-chloro (2H) -benzotriazole-2-2, which is a benzotriazole-based ultraviolet absorber, with respect to a homo-type extrusion molding polypropylene resin (100 parts by mass). Yl] -4-methyl-6- (tert-butyl) phenol (0.5 parts by mass), poly [{6- (1,1,3,3-tetramethylbutyl) which is a hindered amine light stabilizer Amino-1,3,5-triazine-2,4diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4 -Piperidyl) imino}] (0.5 parts by mass), and Irganox 1010 (manufactured by Ciba Specialty Chemicals) (0.5 parts by mass) which is a phenolic antioxidant Resin was prepared.
Next, the polyethylene base sheet is bonded by a multilayer extrusion laminating method in which a polypropylene acid-modified resin is used as a material for forming the adhesive resin layer 14 and melt extruded by an extruder together with the material for forming the thermoplastic resin layer 15. An adhesive resin layer 14 and a thermoplastic resin layer 15 were formed on the surface of the layer 13. The thickness of the formed adhesive resin layer 14 was 10 μm, and the thickness of the thermoplastic resin layer 15 was 70 μm.
Subsequently, the surface of the thermoplastic resin layer 15 of the obtained multilayer sheet was subjected to corona discharge treatment, and 2-ethyl-hexanoic acid 2- [4- (4, 4,9) having a molecular weight of 512, which is a low wavelength region triazine ultraviolet absorber. 6-diphenyl- [1,3,5] triazin-2-yl) -3-hydroxy-phenoxy] -ethyl ester, 2- (2hydroxy-4- [1-octyl) which is a high wavelength region triazine UV absorber Oxycarbonylethoxy] phenyl) -4,6-bis (4-phenylphenyl) -1,3,5-triazine, and a hindered amine light stabilizer (bis (1,2,2,6,6-pentamethyl- 2-piperidinyl) sebacate and a mixture of methyl (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate A protective sheet 16 was provided by dry-coating a retane-based topcoat agent to produce a decorative sheet 1A.
The low wavelength region triazine-based ultraviolet absorber and the high wavelength region triazine-based ultraviolet absorber were added so as to be 2.5 parts by mass with respect to 100 parts by mass of the protective layer 16, respectively. Further, the hindered amine light stabilizer was added so as to be 5 parts by mass with respect to 100 parts by mass of the protective layer 16.

[Example 2]
2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl)-, which is a triazole-based UV absorber, is applied to the two-component curable urethane topcoat agent that forms the protective layer 16. A decorative sheet 1B was obtained in the same manner as in Example 1 except that 4- (1,1,3,3-tetramethylbutyl) phenol was further contained. The triazole ultraviolet absorber was added so as to be 2.5 parts by mass with respect to 100 parts by mass of the protective layer 16.

[Example 3]
As a low wavelength region triazine ultraviolet absorber, 2- [4-[(2-hydroxy-3- (2′-ethyl) hexyl) oxy] -2-hydroxyphenyl] -4,6-bis (2) having a molecular weight of 583 , 4-dimethylphenyl) -1,3,5-triazine was used in the same manner as in Example 1 to obtain a decorative sheet 1C.

[Example 4]
As a low wavelength region triazine ultraviolet absorber, 2- [4-[(2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethyl) having a molecular weight of 647 A decorative sheet 1D was obtained in the same manner as in Example 1 except that phenyl) -1,3,5-triazine was used.

[Comparative Example 1]
2-ethyl-hexanoic acid 2- [4- (4,6-diphenyl- [1,3,5] triazin-2-yl) -3 as in Example 1 as a low wavelength region triazine ultraviolet absorber -Hydroxy-phenoxy] -ethyl ester was used, and a decorative sheet 1E was produced in the same manner as in Example 1 except that the high wavelength region triazine-based ultraviolet absorber was not used. However, the low wavelength region triazine ultraviolet absorber and the hindered amine light stabilizer were added so as to be 5 parts by mass with respect to 100 parts by mass of the protective layer 16, respectively.

[Comparative Example 2]
As a high wavelength region triazine ultraviolet absorber, the same 2- (2hydroxy-4- [1-octyloxycarbonylethoxy] phenyl) -4,6-bis (4-phenylphenyl) -1,3 as in Example 1 was used. A decorative sheet 1F was produced in the same manner as in Example 1 except that 5-triazine was used and a low wavelength region triazine-based ultraviolet absorber was not used. However, the high wavelength region triazine ultraviolet absorber and the hindered amine light stabilizer were added so as to be 5 parts by mass with respect to 100 parts by mass of the protective layer as in Comparative Example 1.

[Weather resistance evaluation]
The decorative sheets 1A to 1F obtained in Examples and Comparative Examples were subjected to a weather resistance acceleration test (metal halide lamp type tester, JTM G 01 2000 Japan Testing Machine Industry Association Standard) in order to evaluate the weather resistance. As a tester, a die plastic metal weather (KU-R5CI-A: manufactured by Daipura Wintes Co., Ltd.) was used.
The weathering acceleration test conditions are as follows.
[1] Light source lamp: MW-60W, filter: KF-1 (irradiation range: 295-780 nm), illuminance 65 ± 3 mW / cm ² (measurement range: 330-390 nm)
[2] Light (irradiation) (53 ° C, 50% RH) 20.00 hours [3] Dew (dark condensation) (30 ° C, 98% RH) 4.00 hours [4] Rest (rest) (30 ° C, 98% RH) 0.01 hour A weather resistance acceleration test was conducted with the cycle [2] to [4] (24.01 hours) as one cycle. The shower was performed for 30 seconds before and after Dew.

(UV transmittance)
About the decorative sheet 1A-1F which performed the weather resistance acceleration | stimulation test for 336 hours by the said cycle, the peeling solvent was made to act, and the thermoplastic resin layer 15 and the protective layer 16 were forcedly peeled together. At this time, the thickness was made uniform in any decorative sheet. Next, the transmittance of ultraviolet rays in the low wavelength region (275 nm) and the high wavelength region (335 nm) with respect to the peeled thermoplastic resin layer 15 and protective layer 16 was measured. The results are shown in Table 1.

(Appearance evaluation)
Moreover, about the decorative sheet 1A-1F after performing the weather-resistance acceleration | stimulation test of 336 hours or 480 hours, the external appearance was evaluated by visual observation based on the following references | standards. The evaluation results are shown in Table 1.
A: Deterioration is not seen in the decorative sheet.
○: Slight deterioration is observed, but there is no problem as a decorative sheet.
X: The decorative sheet is deteriorated.

In the decorative sheet 1A of Example 1 and the decorative sheet 1B of Example 2, in the weather resistance evaluation, the ultraviolet ray absorbing ability was high for both the low wavelength region (275 nm) and the high wavelength region (335 nm). In addition, the decorative sheet was not deteriorated even after the 480-hour weather resistance test.
Moreover, also in the decorative sheet 1C of Example 3 and the decorative sheet 1D of Example 4, in the weather resistance evaluation, the ultraviolet absorptivity was high in both the low wavelength region (275 nm) and the high wavelength region (335 nm). In addition, these decorative sheets had no problem as a decorative sheet in which slight deterioration was observed after the 480-hour weather resistance test, and no deterioration was observed after the 336-hour weather resistance test.

On the other hand, the decorative sheet 1E of Comparative Example 1 had a high ultraviolet transmittance in the high wavelength region (335 nm) and was inferior in ultraviolet absorbing ability compared to the Examples. Further, the decorative sheet 1E was deteriorated after a weather resistance test for 336 hours.
Moreover, in the decorative sheet 1D of Comparative Example 2, the transmittance of ultraviolet rays in the low wavelength region (275 nm) was high, and the ultraviolet absorbing ability was inferior to the Examples. In addition, the decorative sheet 1F was deteriorated after a weather resistance test for 336 hours.

  The decorative sheet of the present invention is a decorative sheet used as a construction material such as an interior / exterior member for building, a fitting, a frame material, a flooring material, or a surface material for home appliances, in particular, a wooden board, an inorganic board, a metal plate. It is useful as a decorative sheet used when a decorative sheet is produced by bonding to a sheet, etc., and sufficiently satisfies the weather resistance required for a surface material of a building material for exterior use.

It is sectional drawing which showed an example of embodiment of the decorative sheet of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Cosmetic sheet 11 Base material sheet 12 Picture layer 13 Adhesive layer 14 Adhesive resin layer 15 Thermoplastic resin layer 16 Protective layer 17 Primer layer

Claims (7)

A transparent or translucent protective layer is provided on the base sheet,
The protective layer has a triazine ultraviolet absorber having at least one maximum absorption wavelength in a low wavelength region (250 to 300 nm), and a triazine ultraviolet absorption having at least one maximum absorption wavelength in a high wavelength region (300 to 370 nm). A decorative sheet comprising at least one agent and a hindered amine light stabilizer.   The decorative sheet according to claim 1, wherein the molecular weight of a triazine-based ultraviolet absorber having at least one maximum absorption wavelength in the low wavelength region (250 to 300 nm) is 490 to 650.   The decorative sheet according to claim 1 or 2, wherein the protective layer further contains at least one selected from the group consisting of an inorganic ultraviolet absorber made of a metal oxide and a benzotriazole ultraviolet absorber.   A transparent or translucent thermoplastic resin layer is provided between the base sheet and the protective layer, and the thermoplastic resin layer has a triazine ultraviolet absorber, an inorganic ultraviolet absorber made of a metal oxide, The cosmetic sheet according to any one of claims 1 to 3, wherein at least one selected from the group consisting of benzotriazole-based ultraviolet absorbers and a hindered amine-based light stabilizer are contained.   The decorative sheet according to claim 4, wherein the thermoplastic resin layer is provided on the base sheet via an adhesive resin layer.   The decorative sheet according to claim 4 or 5, wherein the thermoplastic resin layer contains a polyolefin resin.   The decorative sheet according to any one of claims 1 to 6, wherein a pattern layer is provided on the base sheet.

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