JP5966292B2 - Decorative sheet for vacuum forming - Google Patents

Description

  The present invention relates to a decorative sheet for vacuum forming suitable for interior and exterior of a building and decoration of home appliances.

Conventionally, a vinyl chloride sheet containing polyvinyl chloride has been frequently used as a decorative sheet used for interior and exterior of a building and decoration of home appliances. The PVC sheet had the advantage that the interlayer adhesion was high and processing was easy. In particular, the vinyl chloride sheet having a multilayer structure in which a pattern is printed on a base sheet made of polyvinyl chloride resin and a surface protective layer made of transparent polyvinyl chloride resin is provided on the printed surface, the printed layer is protected, Widely used because of its excellent workability and high durability.
However, since the vinyl chloride resin generates chlorine gas and hydrogen chloride gas during combustion, and further causes the generation of harmful substances such as dioxins, decorative sheets using materials that replace polyvinyl chloride have been developed.

Materials that do not contain chlorine, such as polyolefin-based resins, acrylic resins, and polyester-based resins, are used as substitutes for polyvinyl chloride resins, and decorative sheets using these materials have been put into practical use. However, these resins are inferior in adhesiveness compared to polyvinyl chloride resin, and peeling between layers has been a problem in a multi-layer decorative sheet, for example, a multi-layer decorative sheet described above.
Thus, adhesives for increasing the adhesive strength between layers have been studied so far, for example, on a base material sheet made of a thermoplastic resin, through a heat adhesive resin layer made of an acrylic-polyester-vinyl acetate resin. A decorative sheet in which a surface resin layer made of a thermoplastic resin is laminated has been proposed (see Patent Document 1 and Claims).
However, the decorative sheet for vacuum forming having a multi-layer structure is excessively stretched along the shape of the base material to be bonded at the time of vacuum forming processing, so there is a concern that the adhesion strength between the sheet layers is reduced (peeled) after forming. There was still.

JP 2000-326451 A

The inventors of the present invention have intended to enhance the design feeling of the decorative sheet by disposing a decorative layer using a pearl pigment between the layers of the above-described decorative sheet having a multilayer structure. At the time of vacuum forming, the decorative sheet is stretched so that the elongation rate is about 100% depending on the location and the thickness of the decorative sheet is reduced to about half. Therefore, vacuum forming is assumed for the decorative layer arranged in the interlayer part of the decorative sheet. When a pearl pigment having a particle size similar to that of the specification not used was used, a decrease in strength after vacuum forming was confirmed.
In view of the above problems, an object of the present invention is to provide a decorative sheet for vacuum forming that has excellent moldability, does not cause delamination between layers, and is excellent in high-luminance design. Is.

As a result of intensive studies to achieve the above object, the present inventors have found that the above problem can be solved by controlling the volume-based average particle diameter of the pearl pigment. The present invention has been completed based on such findings.
That is, the present invention is a decorative sheet for vacuum forming having a decorative layer, an adhesive layer, and a transparent resin layer in this order on a substrate, the substrate comprising a polyolefin film, and the transparent resin layer comprising a polyester film. becomes, and the decorative layer contains a binder resin and a pearl pigment, volume-based average particle diameter of the pearl pigment is Ri der less 20 [mu] m, the content of the pearl pigment with respect to 100 parts by weight of the binder resin 3-15 The decorative sheet interlayer adhesion strength is 1.6 to 2 at a portion that is part by mass, the decorative layer has a thickness of 1 to 20 μm, the binder resin is made of urethane acrylic resin, and the elongation percentage of the sheet is 100%. The present invention provides a decorative sheet for vacuum forming, characterized in that it is 3 kgf / inch, and a decorative board on which the decorative sheet is affixed to a substrate.

  According to the present invention, it is possible to obtain a decorative sheet for vacuum forming that has excellent molding processability, does not cause separation between layers after the molding process, and is excellent in high-luminance design.

It is a schematic diagram which shows the structure of the decorative sheet of this invention.

  Hereinafter, the configuration of the decorative sheet of the present invention will be described in detail with reference to FIG. The decorative sheet 1 for vacuum forming of the present invention has a decorative layer 3, an adhesive layer 4, a transparent resin layer 5, and a surface protective layer 6 provided as required on a base material 2 in this order.

[Base material]
The base material 2 in the decorative sheet of the present invention is made of a polyolefin film. Examples of the polyolefin include polyethylene (low density, medium density, high density), polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer, and the like. Polyethylene is most preferable from the viewpoint of processability and flexibility.
It is preferable that the polyolefin film used in the present invention has a tensile elastic modulus of 330 MPa or less and a heat shrinkage rate after heating at 100 ° C. for 15 minutes to 3.2% or less.

If the tensile modulus of the polyolefin film is 330 MPa or less, the moldability becomes better.
The tensile elastic modulus is measured by the following measuring method.
<Measurement method of tensile modulus>
Prepare a sheet punched into a dumbbell-shaped test piece conforming to JIS K6732, and use a tensile compression tester (Tensilon RTC-1250A manufactured by Orientec Co., Ltd.) under a temperature environment of 25 ° C., and a tensile speed of 50 mm / min. From the first linear portion of the tensile stress-strain curve obtained by measurement under the condition where the distance between chucks is 80 mm, the calculation was performed according to the following equation.
E = Δρ / Δε
E: Tensile modulus Δρ: Stress difference due to the original average cross-sectional area between two points on a straight line Δε: Strain difference between the same two points

  There are various methods for controlling the tensile modulus of the polyolefin film. For example, the tensile modulus can be increased by increasing the crystallinity of the polyolefin film. Therefore, by controlling the crystallinity, the tensile modulus of the polyolefin film can be controlled to 330 MPa or less. In addition, as a method for controlling the tensile elastic modulus to 330 MPa or less, the addition of a pigment described later and the addition amount thereof, the addition of an inorganic filler such as calcium carbonate and the addition amount thereof, For example, the tensile elastic modulus can be controlled to 330 MPa or less by performing treatment such as irradiation with an electron beam.

Further, as described above, the polyolefin film used in the present invention is preferably controlled to have a heat shrinkage rate of 3.2% or less after being heated at 100 ° C. for 15 minutes. If the heat shrinkage is 3.2% or less, it is possible to more suitably prevent the base material and the transparent resin layer from being peeled off between the layers after molding.
The heat shrinkage rate is measured by the following measuring method.
<Measurement method of heat shrinkage>
A square decorative sheet having a side of 120 mm is prepared, and a straight line of 100 mm is formed in the vertical direction and the horizontal direction passing through the central portion of the sheet. The decorative sheet is heated at 100 ° C. for 15 minutes, then rapidly cooled to room temperature, and the lengths of the straight lines in the vertical and horizontal directions are measured. The change in the length of the straight line in the vertical direction and the horizontal direction was calculated, and the average of the percentage with respect to the length of the straight line (100 mm) before heating was defined as the heat shrinkage rate. (Conforms to JIS K7133.)

  Examples of a method for controlling the heat shrinkage rate of the polyolefin film to 3.2% or less include a method of adding an elastomer component during synthesis of a polyolefin and a method of blending a plurality of polyolefins having different average molecular weights and crystallinity. .

Although there is no restriction | limiting in particular as thickness of the base material 2, From a durable and versatile viewpoint, it is about 20-300 micrometers normally, Preferably it is the range of 30-200 micrometers.
Moreover, it is preferable that the base material 2 is formed with colored resin. When the colored resin is used, the stability of the color tone of the pattern layer formed on the surface of the decorative sheet can be secured, and the surface hue of the substrate that is the adherend to which the decorative sheet is attached varies. Moreover, the hue of the dispersed surface can be well concealed.

The colorant used for the above-described purpose may be appropriately selected depending on the application. For example, the base material 2 can be colored transparent or colored opaque. Generally, since it is necessary to conceal the surface of the adherend, it is preferable to make it colored and opaque. Colorants 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, isoindolinone yellow, phthalocyanine Organic pigments or dyes such as blue, and pearl pigments described later are used.
The addition amount of the colorant is usually about 1 to 50 parts by mass with respect to 100 parts by mass of the resin material forming the base material 2 described above.

The base material in the decorative sheet of the present invention is such that a primer layer for reinforcing interlayer adhesion between the base material and other layers, adhesion to various adherends, and a back primer layer are formed. Processing may be performed. The material used for forming the primer layer is not particularly limited, and examples thereof include acrylic resins, vinyl chloride-vinyl acetate copolymers, polyesters, polyurethanes, chlorinated polypropylenes, and chlorinated polyethylenes. The material used for the back primer layer is appropriately selected depending on the adherend.
Furthermore, an inorganic filler may be added to the base material as necessary, and powders such as calcium carbonate, barium sulfate, clay, talc, silica (silicon dioxide), and alumina (aluminum oxide) are listed. It is done. The addition amount of the inorganic filler is usually about 1 to 50 parts by mass with respect to 100 parts by mass of the resin material forming the base material 2 described above.
In addition, the substrate 2 may be blended with other various additives, for example, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, a light stabilizer and the like as necessary.

[Decoration layer]
The decorative layer 3 according to the present invention needs to contain a pearl pigment, and the pearl pigment needs to have a volume-based average particle size of 20 μm or less. This is because if the thickness exceeds 20 μm, the adhesion strength between the decorative sheet layers after vacuum forming is lowered. The volume-based average particle diameter of the pearl pigment is preferably 5 to 20 μm, and more preferably 7 to 20 μm.
Examples of the average particle size include a volume-based average particle size, a mass-based average particle size, and a number-based average particle size. In the present invention, the volume-based average is used from the viewpoint of increasing the adhesion strength with the decorative layer as an interface. It must be a particle size.

The ink used for the decorative layer 3 includes a binder, the above-mentioned pearl pigment as a colorant, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, and other colorants and extenders as necessary. Are appropriately mixed.
It is preferable to mix | blend 3-15 mass parts of pearl pigments with respect to 100 mass parts of binders. If it is 3 parts by mass or more, high brightness design can be enjoyed, and if it is 15 parts by mass or less, the adhesive strength between the decorative sheets after vacuum forming is easily ensured.
As thickness of the decoration layer 3, 1-20 micrometers is preferable. If it is 1 micrometer or more, since high brightness design property can be enjoyed, it is preferable, and if it is 20 micrometers or less, it becomes easy to ensure the adhesion strength between the decorative sheets between vacuum forming, and is preferable.

The pearl pigment used in the decorative layer 3 is a mica-based material in which the surface of natural mica or artificial mica is coated with a metal oxide and / or metal oxide hydrate of a metal such as titanium, zirconium, silicon, aluminum, and cerium. A pearl pigment etc. are mentioned, For example, a titanium dioxide covering mica is used suitably.
Further, as a colorant, carbon black (black), iron black, titanium white, antimony white, chrome yellow, titanium yellow, petal, cadmium red, ultramarine, cobalt blue and other inorganic pigments, quinacridone red, Organic pigments such as indolinone yellow and phthalocyanine blue or dyes, metal pigments made of scaly foils such as aluminum and brass, and the like may be added within a range that does not adversely affect the high brightness design.

  The binder used for the decorative layer 3 is not particularly limited, and examples thereof include polyurethane resins, urethane acrylic resins, vinyl chloride / vinyl acetate copolymer resins, vinyl chloride / vinyl acetate / acrylic copolymer resins, and chlorine. Arbitrary polypropylene resin, acrylic resin, polyester resin, polyamide resin, butyral resin, polystyrene resin, nitrocellulose resin, cellulose acetate resin, etc. A mixture of the above is used.

The decorative layer 3 in the decorative sheet of the present invention imparts decorative properties to the decorative sheet of the present invention, and may be a uniform and uniform colored layer covering the entire surface, and various patterns can be printed with ink and a printing machine. It may be a pattern layer formed by printing using Moreover, you may have both of these.
As the pattern of the pattern layer, a grain pattern simulating the surface of a rock such as a grain pattern, marble pattern (for example, travertine marble pattern), a fabric pattern simulating a texture or cloth pattern, a tiled pattern, a brickwork pattern, etc. There are also patterns such as parquet and patchwork that combine these. These patterns can be formed by multicolor printing with normal yellow, red, blue, and black process colors, and also by multicolor printing with special colors prepared by preparing individual color plates that make up the pattern. Is done.

[Adhesive layer]
As the adhesive constituting the adhesive layer 4 in the decorative sheet of the present invention, an adhesive usually used in a decorative sheet can be used, and the thickness thereof is about 0.1 to 50 μm. When the thickness is 0.1 μm or more, sufficient adhesiveness is obtained, and when the thickness is 50 μm or less, it is advantageous in terms of moldability. From the above viewpoint, the thickness of the adhesive layer is preferably in the range of 3 to 30 μm.
The adhesive is not particularly limited, and examples thereof include urethane-based adhesives, acrylic adhesives, epoxy-based adhesives, rubber-based adhesives, etc. Among them, urethane-based adhesives are used in terms of adhesive strength and the like. preferable. Such urethane adhesives include two-component curable urethane resin adhesives, and two-component curable urethane resin adhesives include various hydroxyl groups such as polyether polyol, polyester polyol, and acrylic polyol. It is an adhesive using a two-component curable urethane resin containing a containing compound and various polyisocyanate compounds such as tolylene diisocyanate and hexamethylene diisocyanate.
Acrylic-polyester-vinyl acetate resins and the like are also suitable adhesives that can easily exhibit adhesiveness by heating and maintain adhesive strength even when used at high temperatures.
The adhesive layer can be formed by a known layer forming method such as a coating method using an adhesive composition composed of these resins and the like.

[Transparent resin layer]
The transparent resin layer 5 in the decorative sheet of the present invention is made of a polyester resin having transparency. Here, the term “transparent” includes colorless and transparent, as well as colored and translucent.
It does not specifically limit as a polyester resin, What is normally used in the field | area of a decorative sheet can be used. Examples thereof include polyethylene terephthalate (hereinafter sometimes referred to as “PET”), polybutylene terephthalate, polyethylene naphthalate, polyarylate, polycarbonate, ethylene terephthalate-isophthalate copolymer, polyarylate, and the like. Among these, polyethylene terephthalate, polybutylene terephthalate, and the like are preferable, and polyethylene terephthalate is particularly preferable.
As the polyester resin, in addition to various homopolymers, copolymerized polyester resins and polyester thermoplastic elastomers to which various copolymerization components or modifying components are added for the purpose of softening the resin can be used. For example, in the case of PET, in the condensation polymerization reaction of terephthalic acid and ethylene glycol, as the dicarboxylic acid component, for example, long-chain aliphatic dicarboxylic acids such as sebacic acid, eicoic acid, dodecanedioic acid, dimer acid, cyclohexanedicarboxylic acid, and the like / Or an alicyclic dicarboxylic acid can be introduced. In addition, polyether diols having hydroxyl groups at both ends, such as polyethylene glycol and polytetramethylene glycol, can be introduced as the diol component.
Since the decorative sheet of the present invention uses a polyester resin for the transparent resin layer 5, it is advantageous for mirror finishing.

In the present invention, the polyester film used as the transparent resin layer 5 is formed into a film by, for example, a calendar method, an inflation method, a T-die extrusion method, and the like, and is prepared by biaxial stretching.
The thickness of the transparent resin layer is about 50 to 400 μm. When the thickness is 50 μm or more, it is difficult to pick up the unevenness of the adherend when it is processed into a decorative board, and the surface is finished beautifully. On the other hand, if it is 400 μm or less, it is advantageous in terms of moldability. From the above viewpoint, the thickness of the transparent resin layer is preferably in the range of 100 to 300 μm.
Moreover, as a method of laminating a transparent resin layer through a base material having a decoration layer and an adhesive layer, dry lamination, a method by heat fusion, or the like can be used.

[Surface protective layer]
In the decorative sheet of the present invention, it is preferable to provide the surface protective layer 6 on the transparent resin layer in order to impart scratch resistance, abrasion resistance, chemical resistance and the like.
The surface protective layer is formed by coating a resin composition containing a curable resin directly or via another layer on the transparent resin layer and crosslinking and curing the resin composition. By constituting the surface protective layer with a crosslinked cured product of a curable resin, the surface characteristics of the decorative sheet can be improved.
As the curable resin used here, a thermosetting resin such as an ionizing radiation curable resin or a two-component curable resin is used, and a plurality of these are used, for example, an ionizing radiation curable resin and a thermosetting resin are used in combination. The so-called hybrid type may be used.
Of these, ionizing radiation curable resins are preferred from the viewpoint of increasing the crosslink density of the resin forming the surface protective layer and improving the surface wear resistance and scratch resistance, and are coated without solvent. In view of easy handling and handling, an electron beam curable resin is more preferable.
On the other hand, when workability is taken into consideration, it is preferable to use a two-component curable resin described in detail later as the curable resin.

(Ionizing radiation curable resin)
The ionizing radiation curable resin refers to a resin having an energy quantum capable of crosslinking and polymerizing molecules in an electromagnetic wave or a charged particle beam, that is, a resin that is crosslinked and cured by irradiation with ultraviolet rays or electron beams. Specifically, it can be appropriately selected from polymerizable monomers, polymerizable oligomers, or prepolymers conventionally used as ionizing radiation curable resins.
Typically, a (meth) acrylate monomer having a radical polymerizable unsaturated group in the molecule is suitable as the polymerizable monomer, and among them, a polyfunctional (meth) acrylate is preferable. Here, “(meth) acrylate” means “acrylate or methacrylate”, and other similar ones have the same meaning. The polyfunctional (meth) acrylate is not particularly limited as long as it is a (meth) acrylate having two or more ethylenically unsaturated bonds in the molecule. These polyfunctional (meth) acrylates may be used singly or in combination of two or more.

Next, as the polymerizable oligomer, an oligomer having a radical polymerizable unsaturated group in the molecule, for example, epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate The system etc. are mentioned.
Furthermore, other polymerizable oligomers include polybutadiene (meth) acrylate oligomers with high hydrophobicity that have (meth) acrylate groups in the side chain of polybutadiene oligomers, and silicone (meth) acrylate oligomers that have polysiloxane bonds in the main chain. In a molecule such as an aminoplast resin (meth) acrylate oligomer modified with an aminoplast resin having many reactive groups in a small molecule, or a novolak epoxy resin, bisphenol epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc. There are oligomers having a cationic polymerizable functional group.

  In the present invention, a monofunctional (meth) acrylate can be appropriately used in combination with the polyfunctional (meth) acrylate and the like within a range that does not impair the object of the present invention, for the purpose of reducing the viscosity. . These monofunctional (meth) acrylates may be used alone or in combination of two or more.

  The coating of the resin composition for forming the surface protective layer is such as gravure coating, bar coating, roll coating, reverse roll coating, comma coating so that the thickness after curing is usually about 1 to 20 μm. It is carried out by a known method, preferably gravure coating. Moreover, from the viewpoint of obtaining excellent weather resistance and its durability, as well as transparency and antifouling properties, the thickness after curing is preferably 2 to 20 μm.

  In the present invention, the uncured resin layer formed by application of the ionizing radiation resin composition becomes a surface protective layer by irradiating with ionizing radiation such as an electron beam and ultraviolet rays and crosslinking and curing. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin used and the thickness of the layer, but the uncured resin layer is usually cured at an acceleration voltage of about 70 to 300 kV. Is preferred.

The irradiation dose is preferably such that the crosslinking density of the ionizing radiation curable resin is saturated, usually 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 200 kGy (1 to 20 Mrad), more preferably 10 to 50 kGy (1). -5 Mrad).
The electron beam source is not particularly limited, and for example, various electron beam accelerators such as a Cockloft 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 are used. be able to.
When ultraviolet rays are used as 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.

  The surface protective layer may have a recess. There is no restriction | limiting in particular about the method of giving a recessed part to a surface protective layer, For example, it gives by embossing. The embossing may be performed by a normal method using a known single-wafer or rotary embossing machine.

  Various additives other than the above can be contained in the resin composition constituting the surface protective layer of the decorative sheet of the present invention as long as the performance is not impaired. Examples of various additives include polymerization inhibitors, crosslinking agents, antistatic agents, adhesion improvers, antioxidants, leveling agents, thixotropic agents, coupling agents, plasticizers, antifoaming agents, fillers, and solvents. Etc.

[Primer layer]
In the decorative sheet of the present invention, a primer layer can be provided in any one of the layers in order to improve the adhesion between the layers as necessary. The primer layer is a transparent or translucent layer, and can be formed of the same binder resin as that used for the decorative layer. About the thickness of a primer layer, it is about 0.5-20 micrometers normally, Preferably, it is the range of 1-5 micrometers.

The base material and each layer constituting the decorative sheet of the present invention can contain a weathering agent as necessary. As a weathering agent, it is preferable to contain at least one selected from an ultraviolet absorber (UVA) and a light stabilizer.
The ultraviolet absorber may be either inorganic or organic, and as the inorganic ultraviolet absorber, titanium dioxide, cerium oxide, zinc oxide or the like having an average particle size of about 5 to 120 nm can be preferably used. Examples of the organic ultraviolet absorber include benzotriazole-based compounds, specifically 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-). Amylphenyl) benzotriazole, 3- [3- (benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl] propionic acid ester of polyethylene glycol, and the like.
Examples of the light stabilizer include hindered amines (hereinafter referred to as “HALS”), specifically 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2′-n-butylmalon. Acid bis (1,2,2,6,6-pentamethyl-4-piperidyl), bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6- And tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate. Moreover, as a commercial item, the product name "Tinubin 123" by Ciba Specialty Chemicals is mentioned.
0.1-10 mass parts is preferable with respect to 100 mass parts of resin which comprises a base material and each layer, and, as for content of a ultraviolet absorber and / or a light stabilizer, 1-10 mass parts is more preferable, 3- 10 parts by mass is more preferable. When the content of the ultraviolet absorber and / or the light stabilizer is within the above range, the absorber or the like does not bleed out and sufficient ultraviolet absorbing ability is obtained, so that excellent weather resistance is obtained.

[Decorative board]
The decorative board of the present invention is obtained by laminating the decorative sheet by vacuum forming. Examples of the substrate that is an adherend include plate materials such as flat plates and curved plates, three-dimensional articles, sheets (or films), and the like. For example, wood board materials such as wood veneer, such as wood veneer, wood plywood, particle board, MDF (medium density fiber board), etc., wood board materials used as 3D shaped articles, etc., board materials such as iron and aluminum, 3D shaped articles or Ceramic materials used as plate materials and three-dimensional articles such as metal materials used as sheets, ceramics such as glass and ceramics, non-cement ceramic materials such as gypsum, non-ceramic ceramic materials such as ALC (lightweight cellular concrete) plates Material, acrylic resin, polyester resin, polystyrene resin, polyolefin resin such as polypropylene, ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenol resin, vinyl chloride resin, cellulose resin, rubber plate, three-dimensional shape Examples thereof include resin materials used as articles or sheets.

As a vacuum forming method for laminating the decorative sheet of the present invention on the adherend, the decorative sheet fixed to the fixed frame is heated with a heater through a silicone rubber sheet until the decorative sheet is softened to a predetermined temperature, and the heated and softened makeup is applied. A vacuum molding die is pressed against the sheet, and at the same time, air is sucked from the vacuum molding die with a vacuum pump or the like to firmly adhere the decorative sheet to the vacuum molding die. If necessary, compressed air pressing from the decorative sheet side may be used in combination.
At the time of vacuum forming, the decorative sheet is applied while being stretched. For this reason, the decorative sheet is stretched up to about 100%, and the thickness of the decorative sheet is also halved.
After the decorative sheet comes into close contact with the vacuum forming mold, the decorative sheet is cooled, the vacuum forming mold is removed from the molded decorative sheet, and the decorative sheet formed from the fixed frame is removed. Vacuum forming is usually performed at about 80 to 130 ° C, preferably about 90 to 120 ° C.

  The decorative board manufactured as described above is also optionally cut by the decorative board, and optionally decorated such as grooving and chamfering on the surface and the mouth using a cutting machine such as a router or a cutter. Can be applied. And various uses, for example, interior or exterior materials of buildings such as walls, ceilings, floors, window frames, doors, handrails, skirting boards, surrounding edges, surface decorative boards for fittings such as malls, kitchens, furniture or light electrical appliances, It can be used for surface decorative boards of cabinets such as OA equipment, interiors and exteriors of vehicles.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example.
(Evaluation method)
(1) Volume-based average particle size of pearl pigment The volume-based average particle size (μm) was measured using a laser diffraction scattering type particle size distribution measuring device “LMS-2000e” manufactured by Seishin Enterprise Co., Ltd.
(2) Interlaminar adhesion strength after forming processing For decorative sheets produced in each of the examples and comparative examples, after processing using a membrane-type vacuum forming processing machine, the portion corresponding to the small edge of the substrate, that is, the sheet is the most The stretched sheet interlayer adhesion strength is selected by selecting the stretched part (the part where the sheet elongation is 100% and the sheet thickness is reduced to 1/2 before vacuum forming). Was measured. The measurement was performed using a tensile tester {"Tensilon Universal Tester RTC-1250A" manufactured by A & D Co., Ltd.}, and evaluated by the peel strength when pulled in the 90 degree direction (kgf / inch). . Further, the case where the peel strength was less than 1 kgf / inch was indicated as “X”, and the case where the peel strength was 1 kgf / inch or more was indicated as “◯”.
(3) High brightness design property The surface of the produced decorative sheet was visually observed and evaluated according to the following criteria.
“◯” indicates that the brightness feeling due to the pearl pigment was recognized, “◎” indicates that the brightness feeling was remarkably recognized, and “x” indicates that the brightness feeling was not recognized at all.

Example 1
A white polyethylene resin sheet (thickness: 100 μm) having a tensile elastic modulus of 150 MPa and a heat shrinkage rate of 1.6% is prepared as the base material 2, and a decorative layer 3 having a thickness of 3 μm (application amount: 3 g / m) is formed on the base material 2. ² ) provided. As the colorant composition constituting the decorative layer 3, a pigment containing 10 parts by mass of a pearl pigment having a volume-based average particle diameter of 18.5 μm is used as a pigment with respect to 100 parts by mass of a binder made of urethane acrylic resin. It was.
Next, as a resin sheet constituting the transparent resin layer 5, a transparent PET base material (“Diarail AK004” manufactured by Ryosei Resin Co., Ltd., thickness 200 μm) is prepared, and the urethane sheet is used as the resin sheet. An adhesive layer 4 having a thickness of 10 μm was provided.
Next, the base material 2 and the resin sheet were laminated by a dry laminating method so that the decoration layer 3 and the adhesive layer 4 were in contact with each other.
Next, the following electron beam curable resin composition is applied onto the transparent resin layer 5 so that the thickness after drying is 5 μm, and irradiated with an electron beam under the conditions of 165 kV and 5 Mrad (50 kGy). The linear curable resin composition was crosslinked and cured to form a surface protective layer, and the decorative sheet of Example 1 was obtained. The results of evaluating the decorative sheet by the above method are shown in Table 1.
The electron beam curable resin composition forming the surface protective layer is as follows.
Bifunctional urethane acrylate oligomer: 100 parts by mass Hydroxyphenyltriazine-based UV absorber: 3 parts by mass Product name “Tinuvin 479”, manufactured by BASF Japan Ltd. Light stabilizer having a reactive functional group (reactive HALS): 3 parts by mass 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate,
Product name “Sanol LS-3410”, manufactured by Nippon Emulsifier Co., Ltd.

Example 2
A decorative sheet was obtained in the same manner as in Example 1 except that a pearl pigment having a volume-based average particle diameter of 12.6 μm was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Example 3
A decorative sheet was obtained in the same manner as in Example 1 except that a pearl pigment having a volume-based average particle size of 9.9 μm was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Comparative Example 1
A decorative sheet was obtained in the same manner as in Example 1 except that a pearl pigment having a volume-based average particle diameter of 24.6 μm was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Comparative Example 2
A decorative sheet was obtained in the same manner as in Example 1 except that the pearl pigment was not used and 10 parts by mass of the titanium oxide pigment was used instead. The results evaluated in the same manner as in Example 1 are shown in Table 1.

  The decorative sheet for vacuum forming obtained by the present invention is useful for interior and exterior of a building such as a house and for decoration of home appliances.

DESCRIPTION OF SYMBOLS 1 Decorative sheet 2 Base material 3 Decoration layer 4 Adhesive layer 5 Transparent resin layer 6 Surface protective layer

Claims (6)

A decorative sheet for vacuum forming having a decorative layer, an adhesive layer, and a transparent resin layer in this order on a base material, the base material comprising a polyolefin film, the transparent resin layer comprising a polyester film, and the decorative layer There a binder resin and a pearl pigment, volume-based average particle diameter of the pearl pigment is Ri der less 20 [mu] m, the content of the pearl pigment is 3 to 15 parts by mass relative to 100 parts by weight of the binder resin, the decorative The thickness of the layer is 1 to 20 μm, the binder resin is made of urethane acrylic resin, and the adhesive strength between the decorative sheets is 1.6 to 2.3 kgf / inch at the portion where the elongation percentage of the sheet is 100%. A decorative sheet for vacuum forming characterized by the above.
[Measurement Method of Volume-Based Average Particle Size] The volume-based average particle size is measured using a laser diffraction / scattering particle size distribution analyzer. ]   The decorative sheet for vacuum forming according to claim 1, wherein the polyolefin is polyethylene.   The decorative sheet for vacuum forming according to claim 1 or 2, wherein the polyester is polyethylene terephthalate.   The decorative sheet for vacuum forming according to any one of claims 1 to 3, further comprising a surface protective layer on the transparent resin layer.   The decorative sheet for vacuum forming according to claim 4, wherein the surface protective layer is a crosslinked cured product of an ionizing radiation curable resin composition. A decorative board, wherein the decorative sheet according to any one of claims 1 to 5 is attached to a substrate.

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