JP6146083B2 - Decorative sheet - Google Patents

Description

  The present invention relates to a decorative sheet.

  Conventionally, a thermoplastic resin sheet has been used as a decorative sheet having excellent surface protection characteristics such as weather resistance and wear resistance used in various applications such as interior and exterior of buildings, building materials, furniture, and home appliances. As a material, a decorative sheet having a color and a pattern, and further having a thermoplastic resin sheet layer, and a decorative sheet having an uneven shape by embossing the thermoplastic resin sheet layer are known (for example, Patent Document 1). However, the decorative sheet described in Patent Document 1 has a low adhesion between the base material and the thermoplastic resin sheet layer, and from the viewpoint of vinyl chloride removal or from a low cost, the polyolefin resin is applied to the base material and the thermoplastic resin sheet layer. When the sheet is used, there is a problem that the adhesion is further lowered.

  In order to improve adhesion, a thermoplastic resin sheet is used as the base material and the thermoplastic resin sheet layer, and an adhesive layer using a polyester adhesive suitable for adhesion between polyolefin resin sheets is provided between these sheets. It is also being considered. However, although the adhesiveness is improved, there is a problem that the adhesiveness under high temperature and high humidity environment such as the exterior of the building, such as the exterior of the building, that is, the water-resistant adhesiveness is weak. Deployment was difficult. Although various investigations have been made as adhesives, there are problems in terms of weather resistance, heat resistance, workability, etc., including adhesion and water resistance, and a decorative sheet that satisfies these performances at the same time. Long-awaited.

  Then, the method (for example, patent document 2) which improves the adhesiveness of a base material and a surface resin layer by using the composition containing modified olefin resin and isocyanate as an adhesive agent, and modified olefin beads and isocyanate are contained. A method for improving the adhesion between the base material and the surface resin layer by using the composition to be used as the adhesive layer (for example, Patent Document 3) has been proposed. However, in these methods, since the isocyanate used for forming the adhesive layer undergoes hydrolysis, it cannot be satisfactory in terms of water-resistant adhesion and weather resistance.

Japanese Patent Laid-Open No. 6-79830 JP-A-10-119209 JP 10-119202 A

  Under such circumstances, the present invention has an object to provide a decorative sheet having excellent adhesion and water-resistant adhesion, and having excellent weather resistance and workability, and design properties having excellent transparency. To do.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the problem can be solved by the following invention. That is, the present invention provides the following decorative sheet.

1. On the substrate, at least a colored solid layer, a pattern ink layer, and a thermoplastic resin sheet layer are provided in this order, the pattern ink layer includes a binder resin and a modified polypropylene polymer emulsion, and the modified polypropylene polymer emulsion is the binder. 6 to 28 parts by mass with respect to 100 parts by mass of the resin, and the thermoplastic resin sheet layer is a decorative sheet made of a polypropylene resin sheet.
2. 2. The decorative sheet according to 1 above, further comprising a surface protective layer on the thermoplastic resin sheet layer.

  According to the present invention, it is possible to obtain a decorative sheet having excellent adhesion and water-resistant adhesion, and having excellent weather resistance and workability, and design properties with excellent transparency.

It is a schematic diagram which shows the cross section of one aspect of the decorative sheet of this invention. It is a schematic diagram which shows the cross section of one aspect of the decorative sheet of this invention.

  The decorative sheet of the present invention has at least a colored solid layer, a pattern ink layer, and a thermoplastic resin sheet layer in this order on the substrate, the pattern ink layer contains a binder resin and a modified polypropylene polymer emulsion, and the modified The polypropylene polymer emulsion is contained in an amount of 6 to 28 parts by mass with respect to 100 parts by mass of the binder resin, and the thermoplastic resin sheet layer is made of a polypropylene resin sheet. The decorative sheet of the present invention will be described with reference to FIGS.

(Base material)
If the base material 2 is used as a base material of a decorative sheet, it can be used without a restriction | limiting, A resin sheet is preferable and a polyolefin resin sheet is especially preferable. Examples of the polyolefin resin include polyethylene resin, polypropylene resin, polybutene resin, ethylene / propylene copolymer resin, ethylene / propylene / butene copolymer resin, and olefin thermoplastic elastomer. Polypropylene resin is preferred from the viewpoint of surface protection properties such as weather resistance and scratch resistance.

Preferred examples of the polypropylene resin include homopolypropylene resins, random polypropylene resins, block polypropylene resins, and α-olefin copolymers having 2 to 20 carbon atoms other than propylene and having a crystal part of polypropylene. In addition, a propylene-α-olefin copolymer containing 15 mol% or more of ethylene, 1-butene, 1-hexene, 1-octene, 3-methyl-1-butene, 4-methyl-1-pentene, etc., for example, ethylene / Propylene copolymers, ethylene / propylene / butene copolymers and the like are also preferred. Moreover, as a polypropylene resin, you may use the modified polyolefin polymer mentioned later as resin used for a pattern ink layer.
Among these, those having a high melting point are preferable, and homopolypropylene resin is preferable. Since the melting point of the resin sheet of the base material 2 is high, the temperature at the time of laminating the thermoplastic resin sheet layer 5 to be described later is increased. Therefore, the adhesion and water-resistant adhesion that the pattern ink layer 4 to be described later develops. This is an advantage.

The substrate 2 is preferably colored with a colorant. This is because from the viewpoint of design properties, it is possible to conceal the foundation such as a substrate on which the decorative sheet is provided. Colorants that can be used for the substrate include carbon black (black), iron black, titanium white, antimony white, yellow lead, titanium yellow, petal, cadmium red, ultramarine, cobalt blue and other inorganic pigments, quinacridone red, iso Organic pigments such as indolinone yellow and phthalocyanine blue, or metallic pigments composed of scaly foils such as dyes, aluminum and brass, pearl luster composed of scaly foils such as titanium dioxide-coated mica and basic lead carbonate (pearl) A pigment etc. are mentioned preferably.
The amount of the colorant used in the substrate is not particularly limited as long as it does not lower the film-forming property when the substrate is obtained by extrusion molding and the mechanical strength of the substrate.

The resin sheet used for the substrate 2 may be unstretched or biaxially stretched. By using a biaxially stretched sheet, more excellent scratch resistance can be obtained and mechanical strength can be improved as compared with an unstretched sheet or a uniaxially stretched sheet.
The sheet of biaxially stretched polyolefin resin is usually heated to a glass transition temperature (Tg) or higher using a longitudinal stretching machine, preferably stretched about 5 to 30 times, and then glass using a width stretching machine. It is obtained by heating above the transition temperature (Tg) and stretching in the width direction, preferably 5 to 30 times. Moreover, as a draw ratio, it is preferable that the product of the draw ratio of a longitudinal direction and the width direction is 25-600, and it is more preferable that it is 300-500. When the product of the draw ratio and the draw ratios in the longitudinal direction and the width direction are within the above ranges, the mechanical strength of the sheet can be obtained, and during the application of the ink composition constituting, for example, the solid colored layer 3 When ionizing radiation curable resin is used for the formation of the surface protection layer 7 or the surface protective layer 7, no contraction occurs when the ionizing radiation is irradiated.
Furthermore, in order to obtain a sheet having a strong strength in the longitudinal direction, it may be stretched again in the longitudinal direction, or of course, simultaneous biaxial stretching in which the longitudinal direction and the width direction are simultaneously stretched may be performed.

  The thickness of the substrate 2 is usually preferably 20 to 200 μm, more preferably about 40 to 160 μm, and further preferably 40 to 100 μm from the viewpoint of mechanical strength and ease of handling.

When using a resin sheet as the base material 2, an additive may be blended in the resin composition forming the resin sheet, if necessary. Examples of the additive include a filler, a flame retardant, an antioxidant, a lubricant, a foaming agent, an ultraviolet absorber, and a light stabilizer.
Among the above additives, it is preferable to contain an inorganic filler such as calcium carbonate, barium sulfate, clay, and talc from the viewpoint of obtaining excellent processing characteristics. The content of these inorganic fillers is preferably in the range of 1 to 60% by mass with respect to the substrate 2.

  Further, from the viewpoint of improving the adhesion to the colored solid layer 3 or the like, the base material 2 may be subjected to corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone-ultraviolet treatment on one or both sides as desired. A physical or chemical surface treatment such as an oxidation method such as a method or an uneven method such as a sand blast method or a solvent treatment method can be performed.

(Colored solid layer)
From the viewpoint of design, the colored solid layer 3 is provided for the purpose of concealing a base such as a substrate on which the base material 2 and the decorative sheet are provided, and is intended color when the base material 2 is colored or has color unevenness. It is a layer that can adjust the color of the surface by giving. The colored solid layer 3 is a layer formed of a resin composition containing a binder resin and a colorant.
Preferred examples of the binder resin include vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, acrylic resin, polyester resin, polyamide resin, butyral resin, polystyrene resin, alkyd resin, nitrocellulose resin, and cellulose acetate resin. A two-component curable resin containing a main agent and a curing agent is also preferred. Among these, in addition to the concealing function, excellent adhesion between the substrate 2, the pattern ink layer 4, and the thermoplastic resin sheet layer 5 is also obtained, and thus a two-component curable resin is preferable. That is, the colored solid layer 3 is preferably composed of a cured product of a two-component curable resin composition containing a two-component curable resin and a colorant.
The two-component curable resin contained in the two-component curable resin composition is not particularly limited as long as it is a resin that is cured by adding a curing agent to the main agent, and the main agent is a polyol (polyhydric alcohol). A two-component curable urethane resin in which is an isocyanate curing agent is preferred.

  Examples of the main agent include polyols such as polyethylene glycol, polypropylene glycol, butylene glycol, and 1,6-hexanediol, (meth) acrylic acid esters such as methyl (meth) acrylate, and (meth) acrylic acid 2- Acrylic polyol obtained by addition polymerization with a monomer having a hydroxyl group such as hydroxyethyl and 2-hydroxypropyl (meth) acrylate; glycols such as ethylene diol and propylene glycol, adipic acid and maleic acid Polyester polyol obtained by polycondensation reaction with at least one selected from dibasic acids such as phthalic acid and terephthalic acid and acid esters thereof; the above diols and ethylene oxide, propylene oxide Id, polyols having a hydroxyl group preferably as a functional group, such as polyether polyols obtained by addition polymerization of such as tetrahydrofuran. These can be used individually or in mixture of multiple types.

  As the isocyanate curing agent, a conventionally known compound may be appropriately used. For example, aromatic compounds such as 2,4-tolylene diisocyanate (TDI), xylene diisocyanate (XDI), naphthalene diisocyanate, and 4,4′-diphenylmethane diisocyanate. Isocyanate or poly, such as 1,6-hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), methylene diisocyanate (MDI), hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate, etc. Isocyanates are used. In addition, adducts or multimers of these various isocyanates, for example, adducts of tolylene diisocyanate, tolylene diisocyanate trimers, and the like are also used.

  The amount of the curing agent used is preferably 1 to 50 parts by weight, more preferably 3 to 50 parts by weight, still more preferably 3 to 30 parts by weight, particularly preferably 100 parts by weight of the main agent. 3 to 20 parts by mass. When the amount of the curing agent used is within the above range, a good cured state can be obtained, so that excellent adhesion and water-resistant adhesion can be obtained, and excellent workability can be obtained in that no cracking occurs during bending. .

  Of the two-component curable resins, an acrylic urethane resin, in which an acrylic polyol is employed as a main component and the curing agent is an isocyanate curing agent, is particularly preferable. By adopting the acrylic urethane resin, excellent adhesion and water-resistant adhesion can be obtained.

Preferred examples of the colorant contained in the resin composition forming the colored solid layer 3 include those exemplified as the colorant contained in the substrate. The colored solid layer 3 is usually formed with an opaque color for the purpose of concealing the base material 2 and the base, but it is formed with a colored transparent color, and the pattern of the base material 2 can be utilized. What is necessary is just to select suitably from the objective.
The content of the colorant is within a range in which the concealing function of the colored solid layer 3 and the adhesion between the base material 2, the pattern ink layer 4 and the thermoplastic resin sheet layer 5 are ensured and the applicability of the resin composition is not hindered. If so, there is no particular limitation.

  Moreover, the resin composition which forms the coloring solid layer 3 can contain an extender, a solvent, a stabilizer, a plasticizer, a catalyst, a hardening | curing agent, etc. suitably as needed.

  The thickness of the colored solid layer 3 is usually about 0.5 to 20 μm, and preferably 1 to 10 μm. Excellent decorativeness of the decorative sheet can be imparted, and shrinkage does not occur during the production process.

(Picture ink layer 4)
The pattern ink layer 4 is a layer that imparts decorativeness to the decorative sheet of the present invention, and includes a binder resin and a modified polypropylene polymer emulsion, and the modified polypropylene polymer emulsion is 6 parts by mass with respect to 100 parts by mass of the binder resin. It is a layer contained in 28 parts by mass.

  The binder resin is not particularly limited. For example, the resin exemplified as the binder resin used for forming the colored solid layer 3 is preferably used. Among them, a two-part curable resin, in particular, an acrylic polyol is used as a main agent, and a curing agent is used. An acrylic urethane resin in which is an isocyanate curing agent is particularly preferred. By adopting the acrylic urethane resin, excellent adhesion, water-resistant adhesion, and transparency can be obtained.

  Moreover, the preferable range of the usage-amount of a hardening | curing agent is also the same as binder resin used for formation of a colored solid layer, and it is preferable that it is 1-50 mass parts with respect to 100 mass parts of main agents, and 3-50 mass parts. More preferably, it is 3-30 mass parts, More preferably, it is 3-20 mass parts. When the amount of the curing agent used is within the above range, a good cured state can be obtained, so that excellent adhesion and water-resistant adhesion can be obtained, and excellent workability can be obtained in that no cracking occurs during bending. .

The modified polypropylene polymer emulsion is not limited in its form as long as the modified polypropylene polymer is dispersed in water.
The modified polypropylene polymer is obtained by modifying a known polypropylene polymer. Examples of the polypropylene polymer include propylene homopolymer, propylene and linear or branched alkanes having about 2 to 8 carbon atoms such as ethylene and butene, cyclic alkanes such as cyclopentene and cyclohexene, or acetic acid. Preferred examples include copolymers with at least one other monomer selected from vinyl and fatty acid esters such as (meth) acrylic acid esters.

Modification of the polypropylene polymer is performed by using a monomer having one or more ethylenically unsaturated groups such as vinyl group, allyl group, (meth) acryloyl group, for example, styrene, methylstyrene, dimethylstyrene, ethylstyrene, isopropylstyrene, dichlorostyrene. Aromatic unsaturated monomers having one ethylenically unsaturated group such as divinylbenzene, diallylbenzene, divinylnaphthalene, diallylisophthalate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate Preferred examples include unsaturated monomers having two or more ethylenically unsaturated groups such as ethylene glycol dimethacrylate. Further, unsaturated organic acids and derivatives thereof such as unsaturated carboxylic acids having ethylenically unsaturated groups, dicarboxylic acid anhydrides, and dicarboxylic acid anhydride monoesters, and more specifically, (meth) acrylic acid, fumaric acid Preferred examples include unsaturated carboxylic acids such as maleic acid, anhydrides and anhydride monoesters thereof, itaconic acid, anhydrides and anhydride monoesters thereof, and the like. These may be used alone or in combination.
As the unsaturated organic acid and its derivative, maleic anhydride and (meth) acrylic acid are particularly preferable.

  The modified polypropylene polymer can be obtained, for example, by graft polymerization of the unsaturated organic acid and its derivative to a previously polymerized polypropylene polymer, preferably in the presence of a radical polymerization initiator. That is, in the present invention, the modified polypropylene polymer is preferably a graft polymer from the viewpoint of obtaining adhesion, water-resistant adhesion, and transparency.

  More specifically, the modified polypropylene polymer includes a maleic anhydride modified propylene polymer and its chlorinated product, a maleic anhydride modified ethylene-propylene copolymer and its chlorinated product, and a maleic anhydride modified propylene-butene copolymer. Copolymer and its chloride, maleic anhydride modified ethylene-propylene-butene copolymer and its chloride, acrylic acid modified propylene polymer and its chlorinated product, acrylic acid modified ethylene-propylene copolymer and its chlorinated product, acrylic Preferable examples include acid-modified propylene-butene copolymer and its chloride. Of these, maleic anhydride-modified propylene polymers, maleic anhydride-modified ethylene-propylene copolymers, and maleic anhydride-modified propylene-butene copolymers are more preferred.

It is preferable that the modified polypropylene polymer is further bonded to a hydrophilic polymer. Since the hydrophilicity of the polymer is improved, an emulsion having a smaller particle diameter can be obtained, and excellent adhesion, water-resistant adhesion, and transparency can be obtained.
Preferred examples of the hydrophilic polymer include poly (meth) acrylic resin, polyether resin, polyvinyl alcohol resin, starch, corn starch, gelatin, and celluloses. From the viewpoint of easily controlling hydrophilicity, poly (meth) Acrylic resin, polyether resin, and polyvinyl alcohol resin are more preferable.

  Examples of the mode of bonding between the modified polypropylene polymer and the hydrophilic polymer include a graft copolymer obtained by grafting a hydrophilic polymer to the modified polypropylene polymer, and a block copolymer of the modified polypropylene polymer and the hydrophilic polymer. Coalescence is mentioned. From the viewpoint of adhesion, water-resistant adhesion, and transparency, a graft copolymer is preferable.

  The particle diameter of the modified polypropylene polymer emulsion is preferably 3 μm or less, more preferably 1 μm or less, and even more preferably, as a 50% cumulative particle diameter (50% particle diameter) from the finer particle diameter in terms of volume. 0.5 μm or less. The 90% particle size is preferably 1 μm or less, more preferably 0.5 μm or less. By reducing the particle size, the dispersion stability is improved, and the transparency is improved along with the adhesion and water-resistant adhesion. In the present invention, the emulsion has a very small particle size and is a concept including a state where it is dispersed in a single molecule, that is, a state where it is substantially dissolved. From the viewpoints of adhesion, water-resistant adhesion, and transparency. Further, the dissolved state is preferable, and the lower limit of the particle diameter is not particularly limited.

  The content of the modified polypropylene polymer emulsion is required to be 6 to 28 parts by mass with respect to 100 parts by mass of the binder resin. When the content is less than 6 parts by mass, the water-resistant adhesiveness is lowered, and when it is more than 28 parts by mass, the transparency is lowered. From the same viewpoint, the content of the modified polypropylene polymer emulsion is preferably 8 to 23 parts by mass with respect to 100 parts by mass of the binder resin. Here, the content of the modified polypropylene polymer emulsion is a content based on the mass of the emulsion itself, which does not include a dispersion medium such as water.

  Examples of the ink composition used for forming the pattern ink layer 4 include the above binder resin and modified polypropylene polymer emulsion, pigments, dyes and other colorants, as well as extender pigments, solvents, stabilizers, plastics What mixed suitably the agent, the catalyst, the hardening | curing agent, etc. is used.

  The pattern ink layer 4 is a pattern composed of wood grain pattern, stone pattern, cloth pattern, leather pattern, natural leather surface pattern, geometric pattern, abstract pattern, etc., depending on figures, letters, symbols, colors, combinations thereof, etc. Or it has a color and is formed on the colored solid layer 3 as a planar, concavo-convex or convex layer.

  The occupation ratio of the pattern ink layer 4 to the entire decorative sheet is preferably 10% or more, more preferably 20% or more, and further preferably 45% or more. When the occupation ratio of the pattern ink layer 4 is within the above range, excellent adhesion and water-resistant adhesion can be obtained, and excellent decorativeness and transparency can be imparted to the decorative sheet. Further, from the same viewpoint, the occupation ratio of the pattern ink layer 4 is preferably as large as possible, and may be 100% provided over the entire surface of the decorative sheet, and there is no particular limitation on the upper limit value.

The thickness of the pattern ink layer 4 is usually about 0.5 to 20 μm, and preferably 1 to 10 μm. When the thickness of the pattern ink layer 4 is within the above range, excellent adhesion and water-resistant adhesion can be obtained, and excellent decorativeness and transparency can be imparted to the decorative sheet.
In the present invention, by adopting such a pattern ink layer 4, excellent adhesiveness and water-resistant adhesiveness can be obtained without providing an adhesive layer between the substrate 2 and the thermoplastic resin sheet layer 5. can get.

(Thermoplastic resin sheet layer)
The thermoplastic resin sheet layer 5 is a layer provided on the surface of the decorative sheet, and is a layer that imparts a design property with excellent transparency to the decorative sheet. As a thermoplastic resin used for the thermoplastic resin sheet layer 5, polyolefin resin is mentioned preferably.
As polyolefin resin, the polyolefin resin illustrated as a material which comprises the resin sheet of the base material 2 can be employ | adopted preferably. Of these polyolefin resins, polypropylene resins are preferable, and homopolypropylene resins are more preferable. This is because excellent adhesion and water-resistant adhesion can be obtained.
In addition to the thermoplastic resin, the thermoplastic resin sheet may include a colorant and other additives such as a filler, a flame retardant, an antioxidant, a lubricant, a foaming agent, an ultraviolet absorber, and a light stabilizer. Etc. may be comprised by the thermoplastic resin composition containing these.

  The thickness of the thermoplastic resin sheet layer 5 is preferably in the range of 5 to 200 μm, more preferably 10 to 100 μm, from the viewpoint of mechanical strength, ease of handling, and excellent transparency.

(Primer layer)
The primer layer 6 is provided between the thermoplastic resin sheet layer 5 and the surface protective layer 7 when a later-described surface protective layer 7 is provided on the thermoplastic resin sheet layer 5, and the adhesion between these layers is determined. It is a layer that improves

  The material for forming the primer layer 6 is not particularly limited, but it is preferable to use, for example, a two-component curable resin exemplified as the resin used for forming the colored solid layer 3.

  The thickness of the primer layer 6 is usually about 0.5 to 20 μm, and preferably 1 to 10 μm. When the thickness of the primer layer 6 is within the above range, excellent adhesion can be obtained.

(Surface protective layer)
The surface protective layer 7 is a layer that imparts surface protective properties such as weather resistance, stain resistance, scratch resistance, water resistance, and chemical resistance to the decorative sheet of the present invention. The material constituting the surface protective layer 7 is preferably a cured product of a curable resin such as a thermosetting resin or an ionizing radiation curable resin. From the viewpoint of obtaining excellent surface protection characteristics, an ionizing radiation curable resin is used. It is preferable to be comprised with the hardened | cured material of the ionizing radiation-curable resin composition to contain.
Here, the ionizing radiation curable resin composition is a resin composition that is cured by irradiating with ionizing radiation, and the ionizing radiation has an energy quantum capable of polymerizing or crosslinking molecules among electromagnetic waves or charged particle beams. In addition to ultraviolet rays (UV) or electron beams (EB), electromagnetic waves such as X-rays and γ-rays, and charged particle beams such as α-rays and ion rays are also used.

The ionizing radiation curable resin can be appropriately selected from conventionally used polymerizable monomers and polymerizable oligomers or prepolymers.
As the polymerizable monomer, a (meth) acrylate monomer having a radical polymerizable unsaturated group in the molecule is suitable, and among them, a polyfunctional (meth) acrylate monomer is preferred. The polyfunctional (meth) acrylate monomer is not particularly limited as long as it is a (meth) acrylate monomer having two or more ethylenically unsaturated bonds in the molecule, and examples thereof include diethylene glycol di (meth) acrylate and propylene glycol diester. (Meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) An acrylate etc. are mentioned preferably. These (meth) acrylate monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the present invention, the number of functional groups of the polyfunctional (meth) acrylate monomer is not particularly limited as long as it is 2 or more, but from the viewpoint of excellent surface protection properties such as chemical resistance, stain resistance, or high smoothness. 2-8 are preferable, and 3-6 are more preferable.

Next, as the polymerizable oligomer, an oligomer having a radical polymerizable unsaturated group in the molecule, for example, a urethane (meth) acrylate oligomer, an epoxy (meth) acrylate oligomer, a polyester (meth) acrylate oligomer, a polyether (meth) acrylate. Preferred are (meth) acrylate oligomers such as oligomers and acrylic (meth) acrylate oligomers, and these oligomers can be used singly or in combination of two or more.
Of the above polymerizable (meth) acrylate oligomers, polyfunctional urethane (meth) acrylate oligomers are preferred. This is because the decorative sheet of the present invention can be imparted with surface protection characteristics such as stain resistance, weather resistance, solvent resistance, abrasion resistance and scratch resistance, and does not shrink during the production process.

  In the present invention, the number of functional groups of the polyfunctional (meth) acrylate oligomer is not particularly limited as long as it is 2 or more, but 2 to 8 is preferable, and 2 to 6 is more preferable. When the number of functional groups is within the above range, the decorative sheet of the present invention can be given surface protection characteristics such as stain resistance, weather resistance, solvent resistance, abrasion resistance, scratch resistance, and the like in the production process. It is because it does not shrink.

  The weight average molecular weight (polystyrene equivalent weight average molecular weight measured by GPC method) of the polyfunctional (meth) acrylate oligomer is preferably 1,000 to 20,000, and preferably 1,000 to 10,000. It is more preferable.

  Examples of the monofunctional (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, and cyclohexyl (meth) ) Acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, and the like. These monofunctional (meth) acrylates may be used alone or in combination of two or more.

When an ultraviolet curable resin is used as the ionizing radiation curable resin, it is desirable to add about 0.1 to 5 parts by mass of the photopolymerization initiator with respect to 100 parts by mass of the resin. The initiator for photopolymerization can be appropriately selected from those conventionally used, and is not particularly limited. For example, the initiator for photopolymerization such as benzoin, acetophenone, phenylketone, benzophenone, and anthraquinone An agent is preferably mentioned.
Moreover, as a photosensitizer, p-dimethylbenzoic acid ester, tertiary amines, a thiol type sensitizer, etc. can be used, for example.

  The ionizing radiation curable resin used in the present invention is preferably electron beam curable. In the case of electron beam curable, solvent-free is possible, which is more preferable from the viewpoint of environment and health, and does not require a photopolymerization initiator, and stable curing characteristics can be obtained.

  In the ionizing radiation curable resin composition, various additives such as a filler (filler) such as an abrasion resistant filler, a mat forming filler, and a flaw resistant filler, or an ultraviolet absorber (UVA) or a hindered amine for improving weather resistance. A weathering agent such as a light stabilizer (HALS) can be contained. These weathering agents are reactive ultraviolet absorbers having reactive functional groups having ethylenic double bonds such as (meth) acryloyl groups, vinyl groups, and allyl groups, or reactive light stabilizers (HALS). It is preferable from the point that stable weather resistance can be obtained without causing bleeding out of the weathering agent.

  In addition, the ionizing radiation curable resin composition is used as various additive components for the purpose of improving the concealing property of the surface protective layer 5 in the resulting decorative sheet, preventing yellowing of the base material, and improving light resistance. Inorganic color pigments such as aluminum paste and carbon black can be appropriately added.

  The thickness of the surface protective layer 7 is preferably 10 to 45 μm, and more preferably 10 to 35 μm. When the thickness of the surface protective layer 7 is within the above range, surface protective properties such as weather resistance, stain resistance, scratch resistance, water resistance and chemical resistance can be obtained.

(Back primer layer)
The back primer layer 8 is a layer that is preferably provided for the purpose of improving the adhesion between the substrate 2 and various adherends, and is the surface opposite to the surface on the side of the substrate 2 where the colored solid layer 3 is provided. Provided on the back side.
The material used for forming the back primer layer 8 is not particularly limited, and preferably includes urethane resin, acrylic resin, polyester resin, vinyl chloride / vinyl acetate copolymer, chlorinated polypropylene resin, chlorinated polyethylene resin, and the like. What is necessary is just to select suitably by a to-be-adhered material.
Moreover, it is preferable that the thickness of the back surface primer layer 8 is about 1-5 micrometers, More preferably, it is 1-3 micrometers. When the thickness is within the above range, excellent performance as a primer layer can be obtained efficiently.

(Uneven pattern)
The decorative sheet of the present invention can be provided with a concavo-convex pattern on the surface thereof from the viewpoint of improving the concavo-convex feeling and texture. For example, when the pattern ink layer 4 presents a wood grain pattern, it is possible to express a wood grain pattern with excellent texture by synchronizing the wood grain pattern conduit portion with the concavo-convex pattern. Also, for example, when the pattern ink layer 4 has a tiled pattern, a tile closer to the real one where the joint groove part visually becomes a concave part by synchronizing the joint groove part and the uneven pattern of the tile application. A paste pattern is obtained.

(Production method)
The decorative sheet of the present invention includes, for example, a step (1) a step of providing a colored solid layer and a pattern ink layer on a substrate, a step (2) a step of providing a thermoplastic resin sheet layer so as to face the pattern ink layer. If necessary, it can be produced by sequentially passing the step (3) the step of providing a surface protective layer on the thermoplastic resin sheet layer.

Step (1) is a step of providing the colored solid layer 3 and the pattern ink layer 4 on the substrate 2.
First, a polyolefin resin composition constituting a resin sheet used for the substrate 2, for example, a polyolefin resin in which a colorant and other additives are added as desired to a polyolefin resin, for example, a calendar method, an inflation method, a T-die extrusion method, etc. It is obtained by making into a sheet by the method. Biaxial stretching may be performed as necessary.
Moreover, the base material 2 can also perform physical or chemical surface treatments, such as said oxidation method and uneven | corrugated method, on the single side | surface or both surfaces.

The formation method of the colored solid layer 3 and the pattern ink layer 4 is not particularly limited. For example, the colored solid layer 3 is formed using the resin composition used for forming the colored solid layer 3, for example, a roll coating method, It may be formed by various coating methods such as a knife coating method, an air knife coating method, a die coating method, a lip coating method, a comma coating method, a kiss coating method, a flow coating method, and a dip coating method.
Moreover, the pattern ink layer 4 uses the ink composition used for formation of said pattern ink layer 4, for example, gravure printing method, offset printing method, screen printing method, flexographic printing method, electrostatic printing method, inkjet printing. What is necessary is just to apply and form by methods, such as a method. In addition, the hand-drawn method, the ink-sink method, the photographic method, the transfer method, the laser beam drawing method, the electron beam drawing method, the partial vapor deposition method such as metal, the etching method, etc. may be used. Good.

  Moreover, when providing the back surface primer layer 8, if the resin composition which forms the back surface primer layer 8 is suitably selected from the formation method illustrated as a formation method of the coloring solid layer 3 or the pattern ink layer 4, it will apply and form. Good.

Step (2) is a step of providing the thermoplastic resin sheet layer 5 so as to face the pattern ink layer 4. As a method of providing the thermoplastic resin sheet layer 5, a thermoplastic lamination sheet that is preliminarily formed by heating and pressing a sheet-shaped thermoplastic resin sheet, or a thermoplastic resin that forms a thermoplastic resin sheet using a T-die extruder is used. The composition is heated and melted to flow down on the pattern ink layer 4, and is sandwiched between a rubber roll and a cooled metal roll, thereby forming the thermoplastic resin sheet layer 5 and applying it onto the pattern ink layer 4. An EC coating method for bonding and laminating is preferred.
Further, the back primer layer 7 may be formed on the substrate 2 before the thermoplastic resin sheet layer 5 is provided, or may be formed after the thermoplastic resin sheet layer 5 is provided.

Step (3) is a step of providing the surface protective layer 7 on the thermoplastic resin sheet layer 5 formed in the above step (2).
The surface protective layer 7 is suitable for a resin composition to be used by applying a curable resin composition containing a curable resin such as the above-mentioned thermosetting resin or ionizing radiation curable resin on the thermoplastic resin sheet layer 5. It is obtained by curing by a different curing method.
When using an ionizing radiation curable resin composition as the curable resin composition, the surface protective layer 7 applies the ionizing radiation curable resin composition onto the thermoplastic resin sheet layer 5 to cure the resin composition. By forming a cured product, it can be formed.

  The application of the ionizing radiation curable resin composition is a gravure printing method, a bar coating method, a roll coating method, a reverse roll coating on the surface of the thermoplastic resin sheet layer 5 so that the thickness after curing is about 10 to 45 μm. Or a known method such as a comma coating method, preferably a gravure printing method. The viscosity of the ionizing radiation curable resin composition is not particularly limited as long as it is a viscosity capable of forming an uncured resin layer on the surface of the thermoplastic resin sheet layer 5 by a coating method described later.

Next, the uncured resin layer formed by applying the ionizing radiation curable resin composition is irradiated with ionizing radiation such as an electron beam and ultraviolet rays to cure the uncured resin layer, and the ionizing radiation curable resin composition The surface protective layer 7 of the cured product is formed.
When an electron beam is used as the ionizing radiation, the accelerating voltage can be appropriately selected according to the resin used and the thickness of the layer, but it is preferable to cure the uncured resin layer usually at an accelerating voltage of about 70 to 300 kV.

In the irradiation of an electron beam, the transmission capability increases as the acceleration voltage increases. Therefore, when a material that deteriorates due to an electron beam is used as the substrate 2 or the thermoplastic resin sheet layer 5, the penetration depth of the electron beam and the resin By selecting an accelerating voltage so that the thicknesses of the layers are substantially equal, it is possible to suppress the irradiation of the extra electron beam to the base material 2, and minimize the deterioration of the base material 2 due to the excess electron beam. It can be kept in.
The irradiation dose is preferably such that the crosslinking density of the resin layer is saturated, usually 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 100 kGy (1 to 10 Mrad), more preferably 30 to 70 kGy (3 to 7 Mrad). It is selected in the range.
The electron beam source is not particularly limited. For example, various electron beam accelerators such as a cockroft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. Can be used.

  When ultraviolet rays are used as the ionizing radiation, those containing ultraviolet rays having a wavelength of 190 to 380 nm are emitted. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a carbon arc lamp, etc. are used.

When the primer layer 6 is provided between the thermoplastic resin sheet layer 5 and the surface protective layer 7, the primer layer 6 may be provided on the thermoplastic resin sheet layer 5 before the surface protective layer 7 is provided.
The primer layer 6 is formed by applying a resin composition forming the primer layer 6 by a known method such as a gravure printing method, a bar coating method, a roll coating method, a reverse roll coating method, or a comma coating method. be able to.

  In the case of providing a concavo-convex pattern on the surface, the method for forming the concavo-convex pattern is not particularly limited, but embossing using an embossed plate or a shaping sheet, or a transfer sheet having a layer having a concavo-convex pattern is used. And a method of imparting an uneven pattern by transferring a layer having an uneven shape. In the present invention, it is preferable to use embossing from the viewpoint of productivity, and further embossing using an embossed plate is preferable.

  As the embossing, usually an embossing method by heating and pressurization using an embossed plate is preferably used. In the embossing method by heating and pressing, the surface on the surface protective layer side of the decorative sheet is usually heated at about 130 to 180 ° C., and the embossed plate is pressed to shape the uneven pattern of the embossed plate, cooled and fixed. A known sheet-fed or rotary embossing machine can be used.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

(Evaluation method)
1. Evaluation of interlayer adhesion (Normal interlayer adhesion test)
Samples obtained by cutting out decorative sheets obtained in Examples and Comparative Examples to a width of 1 inch (2.5 cm) were peeled off between the pattern ink layer and the thermoplastic resin sheet layer, and a Tensilon universal testing machine (“RTC-1210A type (model number)”). ”, Manufactured by Orientec Co., Ltd.) to measure the peeling strength.
Tensile speed: 50 mm / min, ambient temperature: 20 ° C. Tensile and peel strength when peeled was measured. The peel strength was evaluated according to the following criteria. The evaluation results are shown in Table 1.
A peel strength was 25N or more.
○ The peel strength was 20N or more and less than 25N.
Δ: The peel strength was 18N or more and less than 20N.
X The peel strength was less than 18N.
2. Evaluation of water-resistant interlayer adhesion (water-resistant interlayer adhesion test)
A sample obtained in the same manner as in 1 above was immersed in pure water at 60 ° C. for 72 hours, and then peel strength was measured in the same manner as in 1 above. The peel strength was evaluated according to the following criteria. The evaluation results are shown in Table 1.
○ The peel strength was 0N or more and less than 1N.
Δ: The peel strength was 1N or more and less than 5N.
X The peel strength was 5N or more.
3. Evaluation of Transparency 5 μm on a transparent PET film using a resin composition containing a binder resin and a modified polypropylene polymer emulsion having the same composition as the resin compositions used for forming the pattern ink layers of Examples and Comparative Examples Was obtained. The haze value of the obtained coating film was measured using a direct reading type haze meter (manufactured by Toyo Seiki Co., Ltd.) and evaluated according to the following criteria.
○ The haze value was less than 1.
Δ The haze value was 1 or more and less than 5.
X The haze value was 5 or more.
4). Evaluation of processability Under normal temperature (23 ° C.) and low temperature (5 ° C.) environments, the decorative sheet obtained in the examples and comparative examples was placed on the side of the pattern ink layer in a direction perpendicular to the direction parallel to the pattern direction. The state of the bent portion when it was bent at 180 degrees with a finger so that the surface of the film faced upward was visually observed and evaluated according to the following criteria.
◎ No change in appearance was observed at the bent part under low and normal temperature conditions.
○ Under normal temperature environment, no change in appearance was observed at the bent part.
Δ: Although a slight crack was confirmed at the bent portion in a room temperature environment, whitening did not occur and there was no practical problem.
× Under normal temperature environment, whitening was confirmed along with cracks in the bent part.

Example 1
After corona discharge treatment is applied to both sides of a colored polypropylene resin sheet (thickness: 80 μm, random polypropylene resin, unstretched), a colored solid layer (thickness: 5 μm) is formed on one side using an acrylic urethane resin-based ink. The back primer layer (thickness: 2 μm) was provided on the other side. Next, on the colored solid layer, an acrylic urethane resin-based ink (manufactured by Showa Ink Co., Ltd.) and a modified polypropylene polymer emulsion (maleic anhydride-modified polypropylene homopolymer, particle size: 300 μm, “Aptolock (trade name)”, (Mitsubishi Chemical Co., Ltd.) is a resin composition in which 7 parts by mass is added to 100 parts by mass of the acrylic urethane resin contained in the ink, and a wood grain pattern (plate cell area ratio per unit area: 50%) A pattern ink layer (thickness: 2 μm, occupation ratio: 50%) was formed. Using a T-die extruder, a transparent polypropylene resin (random polypropylene resin) is heated and melted at 200 ° C., and is allowed to flow down on the pattern ink layer, and is sandwiched between a rubber roll and a cooled metal roll. A decorative sheet was obtained through an EC laminating method in which a thermoplastic resin sheet layer 5 was formed on 4. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 1. The resin composition obtained from 100 parts by mass of the acrylic urethane resin used in the pattern ink layer and 7 parts by mass of the modified polypropylene polymer was evaluated for transparency. The evaluation results are shown in Table 1.

Examples 2 to 5 and Comparative Examples 1 to 3
A decorative sheet was obtained in the same manner as in Example 1 except that the amount of the modified polypropylene polymer emulsion added in Example 1 was changed as shown in Table 1. Said evaluation was performed about the obtained decorative sheet and the resin composition obtained from the acrylic urethane resin and the predetermined amount of modified polypropylene polymer used in each example. The evaluation results are shown in Table 1.

* 1, Same as the base material (random PP, homo PP, modified PP).
* 2, EC method: EC coating method, thermal lamination: thermal lamination * 3, the amount of curing agent used relative to 100 parts by mass of the main agent.

Examples 6-10
In Example 1, a decorative sheet was obtained in the same manner as in Example 1 except that the occupation ratio of the pattern ink layer was changed to the occupation ratio described in Table 2 by changing the area ratio of the plate per unit area. It was. The plate area ratio per unit area is equal to the pattern ink layer occupation ratio. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 2.

Example 11
In Example 1, the thermoplastic resin that forms the thermoplastic resin sheet layer is a modified polypropylene polymer (maleic anhydride-modified polypropylene homopolymer, “Modic (trade name)”, manufactured by Mitsubishi Chemical Corporation, melting point: 140 ° C. A decorative sheet was obtained in the same manner as in Example 1 except that the resin was heated and melted at 170 ° C. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 2.

Example 12
In Example 1, a decorative sheet was obtained in the same manner as in Example 1 except that the thermoplastic resin forming the thermoplastic resin sheet layer was a homopropylene resin and the temperature of the resin was heated and melted at 250 ° C. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 2.

Example 13
A decorative sheet obtained in the same manner as in Example 1 having a back primer layer, a substrate, a colored solid layer, a pattern ink layer, and a thermoplastic resin sheet layer in this order, and a primer layer ( Thickness: 2 μm, resin: two-component curable urethane resin (acrylic urethane resin) was formed, and then an ionizing radiation curable resin composition (urethane acrylic oligomer) was applied by gravure printing to form a coating film. Subsequently, the said coating film was bridge | crosslinked and hardened by irradiating an electron beam on conditions of 165 keV and 5 Mrad (50 kGy), and the surface protective layer (thickness: 15 micrometers) was formed. Furthermore, it heated to 140 degreeC with the infrared non-contact-type heater from the surface protective layer side, the embossing by a hot pressure was performed immediately, and the decorative sheet | seat which gave the uneven | corrugated pattern of the grain pattern was obtained. The obtained decorative sheet was evaluated as described above. The evaluation results are shown in Table 2.

Example 14
In Example 1, after providing a colored solid layer and a pattern ink layer on a substrate, a polyolefin resin film (random polypropylene resin, thickness: 80 μm) was heated and pressurized at 170 ° C. so as to be in contact with the pattern ink layer. A decorative sheet was obtained. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 2.

* 1, Same as the base material (random PP, homo PP, modified PP).
* 2, EC method: EC coating method, thermal lamination: thermal lamination * 3, the amount of curing agent used relative to 100 parts by mass of the main agent.

Example 15
In Example 1, the acrylic urethane resin contained in the acrylic urethane resin-based ink forming the pattern ink layer is mainly composed of acrylic polyol, and 10 parts by mass of 1,6-hexamethylene diisocyanate with respect to 100 parts by mass of the main ingredient. A decorative sheet was obtained in the same manner as in Example 1 except that the acrylic urethane resin was blended. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

Examples 16 and 17
In Example 15, decorative sheets of Examples 16 and 17 were obtained in the same manner as in Example 1 except that the blending amounts of 1,6-hexamethylene diisocyanate were 30 and 50 parts by mass. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

Example 18
In Example 1, the acrylic urethane resin contained in the acrylic urethane resin-based ink forming the colored solid layer is mainly composed of acrylic polyol, and 10 parts by mass of 1,6-hexamethylene diisocyanate with respect to 100 parts by mass of the main ingredient. A decorative sheet was obtained in the same manner as in Example 1 except that the blended acrylic urethane resin was used. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

Examples 19 and 20
In Example 18, decorative sheets of Examples 19 and 20 were obtained in the same manner as in Example 1 except that the blending amounts of 1,6-hexamethylene diisocyanate were 30 and 50 parts by mass. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

Example 21
In Example 1, the acrylic urethane resin contained in the acrylic urethane resin-based ink forming the pattern ink layer is mainly composed of acrylic polyol, and 10 parts by mass of 1,6-hexamethylene diisocyanate with respect to 100 parts by mass of the main ingredient. And an acrylic urethane resin contained in an acrylic urethane resin-based ink forming a colored solid layer, the main component being an acrylic polyol, and 10 parts by mass of 1,6- A decorative sheet was obtained in the same manner as in Example 1 except that an acrylic urethane resin blended with hexamethylene diisocyanate was used. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

Example 22
In Example 21, a decorative sheet was obtained in the same manner as in Example 21 except that the amount of the curing agent contained in the acrylic urethane resin-based ink forming the pattern ink layer and the colored solid layer was 50 parts by mass. Said evaluation was performed about the obtained decorative sheet. The evaluation results are shown in Table 3.

* 1, Same as the base material (random PP, homo PP, modified PP).
* 2, EC method: EC coating method, thermal lamination: thermal lamination * 3, the amount of curing agent used relative to 100 parts by mass of the main agent.

  The decorative sheet of the present invention has excellent adhesiveness and water-resistant adhesiveness, and has excellent weather resistance and workability, and design with excellent transparency. The sheet of the present invention is widely used for construction materials such as finishing materials and mounting materials in buildings, or for joinery, and in particular, for use in high temperature and high humidity environments such as kitchens and bathrooms. Preferably used.

1. Cosmetic sheet Base material 3. 3. Colored solid layer Pattern ink layer 5. Thermoplastic resin sheet layer 6. Primer layer 7. Surface protective layer 8. Back primer layer

Claims (13)

On the substrate, at least a colored solid layer, a pattern ink layer, and a thermoplastic resin sheet layer are provided in this order, the pattern ink layer includes a binder resin and a modified polypropylene polymer emulsion, and the modified polypropylene polymer emulsion is the binder. A decorative sheet comprising 8 to 23 parts by mass with respect to 100 parts by mass of the resin, wherein the thermoplastic resin sheet layer is a polypropylene resin sheet.   The decorative sheet according to claim 1, wherein the modified polypropylene polymer emulsion is obtained by modifying a polypropylene polymer with an unsaturated organic acid and a derivative thereof.   The decorative sheet according to claim 2, wherein the unsaturated organic acid and its derivative are at least one selected from unsaturated carboxylic acid, dicarboxylic acid anhydride, and dicarboxylic acid anhydride monoester.   The decorative sheet according to any one of claims 1 to 3, wherein the modified polypropylene polymer emulsion is a graft polymer emulsion.   The decorative sheet according to any one of claims 1 to 4, wherein the binder resin of the pattern ink layer is an acrylic urethane resin.   The decorative sheet according to claim 5, wherein the acrylic urethane resin has an acrylic polyol as a main component, an isocyanate curing agent as a curing agent, and the content of the curing agent is 1 to 50 parts by mass with respect to 100 parts by mass of the main agent.   The colored solid layer contains an acrylic urethane resin, the acrylic urethane resin has an acrylic polyol as a main agent, an isocyanate curing agent as a curing agent, and the content of the curing agent is 1 to 50 parts by mass with respect to 100 parts by mass of the main agent. The decorative sheet according to any one of claims 1 to 6.   The decorative sheet according to any one of claims 1 to 7, wherein an occupation ratio of the pattern ink layer to the entire surface of the decorative sheet is 20% or more.   The decorative sheet according to any one of claims 1 to 8, wherein the thermoplastic resin sheet layer comprises a homopolypropylene resin sheet.   The decorative sheet according to any one of claims 1 to 9, wherein the substrate comprises a polypropylene resin sheet.   The decorative sheet according to claim 10, wherein the polypropylene resin sheet is a homopolypropylene resin sheet.   The decorative sheet according to any one of claims 1 to 11, further comprising a surface protective layer on the thermoplastic resin sheet layer.   The decorative sheet according to claim 12, wherein the surface protective layer comprises a cured product of the ionizing radiation curable resin composition.