JP7047391B2 - Decorative sheet and non-combustible decorative board - Google Patents

Description

The present invention relates to decorative sheets and decorative boards used as building materials for exteriors and interiors of buildings, surface materials for fittings, surface materials for home appliances, and the like. In particular, it is an effective technique for non-combustible decorative boards used by bonding to inorganic boards, metal plates, and the like.

In recent years, there has been an increasing demand for nonflammable decorative boards used for interiors of houses such as walls and ceilings of buildings in order to ensure safety in the event of a fire or the like. In buildings such as residential, commercial facilities, station buildings, airports and other public facilities, in order to prevent the spread of fire in the event of a fire, the decorative board should be covered with Article 108-2, No. 1 and No. 1 of the Building Standards Act Enforcement Ordinance. It is required to meet the technical standards for non-combustible materials described in No. 2.

Conventionally, a soft polyvinyl chloride resin has been used as a decorative sheet that meets the technical standards for such non-combustible materials, but there has been a problem that harmful gas or the like is generated during incineration after disposal. When a polyolefin resin is used instead of the polyvinyl chloride resin, the generation of harmful gas during combustion is suppressed, but the polyolefin resin has excellent combustibility properties, so that it is a non-combustible material. It was difficult to meet the technical standards of.

As a method for ensuring that a decorative sheet using a polyolefin resin meets the technical standards for non-combustible materials described in the above-mentioned laws and regulations, a structure using a polyolefin resin layer containing an inorganic filler such as calcium carbonate has been described in the patent document. It is disclosed in 1 and 2. However, in order to obtain a decorative sheet made of a polyolefin resin that meets the technical standards for non-combustible materials, it is necessary to add a large amount of filler. When a large amount of filler is blended, the filler is secondarily aggregated in the polyolefin resin, and when it is formed into a sheet, the filler aggregate is partially generated, so that the mechanical properties are significantly deteriorated, and the mechanical properties are remarkably deteriorated. There is a problem that it becomes difficult to stack the layers and the post-processability of the obtained decorative sheet is inferior.
Patent Documents 3 and 4 disclose a decorative sheet in which an inorganic filler such as calcium carbonate is dispersed with a nano-sized dispersant and the amount of resin is reduced by highly filling the inorganic filler.

Japanese Patent No. 5461614 Japanese Patent No. 5246279 Japanese Unexamined Patent Publication No. 2016-168830 Japanese Unexamined Patent Publication No. 2016-190467

Here, as a method for obtaining a decorative sheet made of a polyolefin resin that satisfies the above technical standards for non-combustible materials, for example, a method for thinning the base material of the decorative sheet can be mentioned. Further, in general, in order to impart designability to the decorative sheet, a pattern layer is provided on the surface side of the base material. At this time, when the base material is put into the printing machine, the base material is required to have sufficient mechanical strength in order to suppress the deviation of the printing position.

In order to meet this demand, if a stretched film subjected to uniaxial stretching or biaxial stretching is adopted as the base material for the decorative sheet, the base material for the decorative sheet is thinned to improve the nonflammability of the decorative sheet, and at the same time, the cosmetic sheet is made up. It is possible to increase the mechanical strength of the sheet base material and the decorative sheet.

However, when the decorative sheet base material is stretched, the interlayer adhesion between the pattern layer and the surface of the decorative sheet base material is reduced due to the molecular orientation and orientation crystallization of the decorative sheet base material. If the interlayer adhesion is reduced, the pattern layer may be peeled off due to deterioration over time, that is, the durability may be reduced.
The present invention has been made by paying attention to the above problems, and an object of the present invention is to provide a decorative sheet having both strength and durability of a base material for a decorative sheet.

In the decorative sheet according to one aspect of the present invention, at least an adhesive layer and a pattern layer are laminated in this order on a uniaxially stretched or biaxially stretched stretched film, and the adhesive layer has a weight average molecular weight of 60,000 or more and 100,000 or less. The gist is that it contains at least one of maleic acid-modified polypropylene, chlorinated polypropylene, and maleic acid-modified chlorinated polypropylene.
The gist of the non-combustible decorative board according to another aspect of the present invention is that the decorative sheet according to the above aspect is provided on the surface of the non-combustible base material.

According to the present invention, since the decorative sheet has a decorative sheet base material made of a stretched film, mechanical strength can be ensured. Further, by providing an adhesive layer between the stretched film and the pattern layer and blending maleic acid-modified polypropylene, chlorinated polypropylene or maleic acid-modified chlorinated polypropylene in the adhesive layer, the interlayer adhesion is improved and the durability is excellent. You can get a decorative sheet.

It is sectional drawing which shows the laminated structure of the decorative sheet and the non-combustible decorative board which concerns on one Embodiment of this invention.

An embodiment of the present invention will be described with reference to the drawings. Here, the drawings are schematic, and the relationship between the thickness and the plane dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Further, the embodiments shown below exemplify a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention describes the material, shape, structure, etc. of the constituent parts as follows. It is not specific to things. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims described in the claims.

(Constitution)
As shown in FIG. 1, in the decorative sheet 1 according to the present embodiment, the adhesive layer 3 and the pattern layer 4 are laminated in this order on one surface of a stretched film 2 which is a base material for a decorative sheet. Further, as the protective layer of the pattern layer 4, the transparent resin layer 5 and the top coat layer 6 are laminated in this order. In order to improve the design, an embossed pattern 5a may be appropriately provided on the surface of the transparent resin layer 5 on the top coat layer 6 side. Ink can be embedded in the embossed pattern 5a to further improve the design. Further, if there is a problem in the adhesion between the pattern layer 4 and the transparent resin layer 5, an adhesive resin layer 5b may be appropriately provided between the pattern layer 4 and the transparent resin layer 5.

The decorative sheet 1 is attached to the surface of the base material B (a non-combustible base material such as wood boards, inorganic boards, metal plates, etc. to which the decorative sheet 1 is attached) to form a non-combustible decorative board. If there is a problem in the adhesiveness of the stretched film 2 to the base material B, a primer layer 7 may be appropriately provided between the stretched film 2 and the base material B.

The thickness of the decorative sheet 1 is preferably in the range of, for example, 49 μm or more and 360 μm or less. When the thickness of the decorative sheet 1 is within this range, the printing workability at the time of manufacturing the decorative sheet 1 can be improved, and the manufacturing cost can be suppressed. Hereinafter, each part of the decorative sheet 1 will be described in detail.

(Stretched film)
The stretched film 2 is made of a laminated stretched film thinned by uniaxial stretching or biaxial stretching. The stretched film 2 is stretched to improve its mechanical strength. The thickness of the stretched film 2 is preferably 20 μm or more and less than 60 μm, and more preferably 20 μm or more and 40 μm or less. When the thickness of the stretched film 2 is in the range of 20 μm or more and less than 60 μm, both the nonflammability of the decorative sheet 1 and the mechanical strength can be achieved. Further, when the thickness of the stretched film 2 is in the range of 20 μm or more and 40 μm or less, it is more preferable because the nonflammability is further improved.

The nonflammability of the stretched film 2 is a building standard in a heat generation test using a cone calorie meter tester compliant with ISO5660-1 in a state of being bonded to a nonflammable base material (not shown) made of a metal plate, an inorganic material, or the like. It is preferable that it is nonflammable enough to meet the requirements described in Article 108-2, items 1 and 2 of the Law Enforcement Ordinance.

Each layer constituting the stretched film 2 is formed of a resin material and contains a polyolefin-based resin as a main component of the resin material. The main component means, for example, a component of 70 parts by mass or more and 100 parts by mass or less, preferably 90 parts by mass or more and 100 parts by mass or less, of which 100 parts by mass is the resin material constituting the layer.

The polyolefin-based resin constituting the stretched film 2 is preferably a polypropylene-based resin in consideration of running stability. As the polypropylene-based resin, α-olefins (for example, propylene, 1-butene, 1-pentene, 1-hexene, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene) are added to polypropylene. , Tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-hexene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl -1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl Examples thereof include -1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) alone or in combination of two or more. When improving the tensile elastic modulus of the stretched film 2, it is preferable to use highly crystalline polypropylene.

When a substrate having an inert surface such as an olefin-based raw fabric layer is used as the stretched film 2, the front and back surfaces of the stretched film 2 are corona-treated, plasma-treated, ozone-treated, electron beam-treated, ultraviolet-treated, and heavy chromic. It is desirable to perform acid treatment or the like.
The stretched film 2 preferably contains an inorganic pigment. The stretched film 2 plays a role of concealing the pattern of the base material B. In order to obtain the concealing property required from the viewpoint of the design of the decorative sheet 1, the light transmittance is preferably 40% or less. If the concealing property is low, the patterns of the pattern layer 4 and the base material B are mixed, which is not preferable.

By containing the inorganic pigment, it is possible to obtain a decorative sheet 1 having a good hiding property. The mixing amount of the inorganic pigment is preferably 5 parts by mass or more and 50 parts by mass or less, with the resin material being 100 parts by mass. If the mixing amount is small, the hiding property is low, and if the mixing amount exceeds 50 parts by mass, embrittlement of the stretched film 2 may occur, which is not preferable. The inorganic pigment contained is not particularly limited, and examples thereof include natural inorganic pigments and synthetic inorganic pigments.

Examples of the natural inorganic pigment include earth-based pigments, calcined soil, and mineral pigments. Examples of synthetic inorganic pigments include oxide pigments, hydroxide pigments, sulfide pigments, silicate pigments, phosphate pigments, carbonate pigments, metal powder pigments, carbon pigments and the like. Further, a mixed pigment in which one kind or two or more kinds are mixed may be used from the natural inorganic pigment and the synthetic inorganic pigment.
It is not preferable to use an organic pigment as a pigment because the nonflammability of the stretched film 2 is impaired.

(Adhesive layer)
The adhesive layer 3 is made of polypropylene. The material for improving the adhesion to the stretched film 2 is preferably at least one selected from maleic acid-modified polypropylene, chlorinated polypropylene, and maleic acid-modified chlorinated polypropylene. These may be used alone or in combination of two or more. Further, other elastomers may be mixed. When the elastomer is mixed, the type is not particularly limited, but a polypropylene-based elastomer is preferable in terms of compatibility.

Since the adhesive layer 3 needs to uniformly cover the surface on the stretched film 2, it is desirable to manufacture the adhesive layer 3 in a solution state. The type of solvent to be dissolved is not particularly limited, but cyclohexane, methylcyclohexane, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone and the like are preferably used.

(Maleic acid-modified polypropylene)
The maleic acid-modified polypropylene used for the adhesive layer 3 is a polypropylene graft-polymerized with maleic acid, and it is desirable that the weight average molecular weight is large in order to ensure the adhesion to the stretched film 2, and it is 60,000 or more. Must be. On the other hand, if the molecular weight is large when making a solution, the solubility is low and there is a possibility that the adhesive layer 3 becomes non-uniform. Therefore, the molecular weight needs to be 100,000 or less.

The amount of acid modification of the maleic acid-modified polypropylene is preferably 1.0% by mass or more and 2.0% by mass or less from the viewpoint of adhesion to the stretched film 2. The acid denaturation amount can be measured by FT-IR (FTIR8200PC manufactured by Shimadzu Corporation). First, a calibration curve solution in which maleic anhydride is dissolved at an arbitrary concentration is prepared. Next, FT-IR measurement of the calibration curve solution is performed, and a calibration curve is prepared from the absorbance of the expansion and contraction peak (1780 cm ^-1 ) of the carbonyl (C = O) bond of maleic anhydride. Then, FT-IR measurement of a solution of maleic acid-modified polypropylene dissolved in chloroform was performed, and based on the above calibration curve, the absorbance of the expansion and contraction peak (1780 cm ^-1 ) of the carbonyl bond of maleic anhydride was used to determine the maleic acid-modified polypropylene. The amount of acid denaturation is determined.

(Chlorinated polypropylene)
The chlorinated polypropylene used for the adhesive layer 3 is a partially chlorinated polypropylene. In order to ensure the adhesion to the stretched film 2, it is desirable that the weight average molecular weight is large, and it is necessary that the weight average molecular weight is 60,000 or more. On the other hand, if the molecular weight is large when making a solution, the solubility is low and the adhesive layer 3 becomes non-uniform, so the molecular weight needs to be 100,000 or less.

Further, when the chlorine content is large, it becomes easy to make a solution, so a large chlorine content is desirable, and 20% by mass or more is desirable. However, if the chlorine content is increased, the adhesion to the stretched film 2 decreases, so it is desirable that the chlorine content is 30% by mass or less. The chlorine content can be measured by titration according to the method specified in JIS K-7229-1995.

(Maleic acid-modified chlorinated polypropylene)
The maleic acid-modified chlorinated polypropylene used for the adhesive layer 3 is obtained by graft-polymerizing maleic acid on polypropylene and partially chlorinating it. In order to ensure the adhesion to the stretched film 2, it is desirable that the weight average molecular weight is large, and it is necessary that the weight average molecular weight is 60,000 or more. On the other hand, if the molecular weight is large when the solution is formed, the solubility is low and the adhesive layer 3 becomes non-uniform when the adhesive layer 3 is formed. Therefore, the molecular weight needs to be 100,000 or less.

The amount of acid modification of maleic acid-modified chlorinated polypropylene is preferably 1.0% by mass or more and 2.0% by mass or less from the viewpoint of adhesion to the stretched film 2. Further, since it is easy to make a solution when the chlorine content is large, it is desirable that the chlorine content is large, and it is desirable that the chlorine content is 20% by mass or more. However, if the chlorine content is increased, the adhesion to the stretched film 2 is lowered, so that it is preferably 30% by mass or less.

(Picture layer)
As a method for forming the pattern layer 4, there is a method of performing gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, ink jet printing, or the like on the adhesive layer 3. The method of providing the top coat layer 6 described later is also the same as the method of providing the pattern layer 4, and is not limited in any way.

When ink is used to form the pattern layer 4, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, etc. can be used as the ink binder. May be used alone, or may be appropriately selected and used from each modified product. These inks may be water-based, solvent-based (oil-based), or emulsion type, and either one-component type or two-component type using a curing agent can be appropriately selected.

Furthermore, it is also possible to cure the ink by irradiating it with ultraviolet rays, electron beams, or the like. There are various methods for curing ink, but the most common method is a method of curing with isocyanate using urethane-based ink. In addition to these binders, pigments, colorants such as dyes, extender pigments, solvents, and various additives contained in ordinary inks may be added to the ink. Particularly commonly used pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthracinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, pearl pigments such as mica.

In addition to the application of ink, it is also possible to apply the design by vapor deposition or sputtering of various metals.
The thickness of the pattern layer 4 is preferably 3 μm or more and 20 μm or less. When the thickness of the pattern layer 4 is within this range, printing can be clarified, printing workability at the time of manufacturing the decorative sheet 1 can be improved, and manufacturing cost can be suppressed.

(Transparent resin layer)
The transparent resin layer 5 is made of, for example, a transparent resin sheet, and is adhered to the pattern layer 4 with an adhesive. The transparent resin layer 5 may be a single layer or a plurality of layers. The transparent resin layer 5 of the present embodiment is preferably composed of a polyolefin resin as a main component. The main component is, for example, a resin material containing 100 parts by mass of the resin material constituting the transparent resin layer 5 and 70 parts by mass or more and 100 parts by mass or less, preferably 90 parts by mass or more and 100 parts by mass or less.

Examples of the polyolefin resin constituting the transparent resin layer 5 include α-olefins (for example, propylene, 1-butene, 1-pentene, 1-hexene, 1-hexene, 1-octene, and the like, in addition to polypropylene, polyethylene, polybutene, and the like. 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl- 1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl- 1-Hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) are homopolymerized or copolymerized in two or more types. Can be mentioned.

The polyolefin-based resin constituting the transparent resin layer 5 includes an ethylene / vinyl acetate copolymer, an ethylene / vinyl alcohol copolymer, an ethylene / methyl methacrylate copolymer, an ethylene / ethyl methacrylate copolymer, and an ethylene / butyl. Some copolymers of ethylene or α-olefin and other monomers such as methacrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / butyl acrylate copolymer, etc. Can be mentioned. Further, when improving the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene.

The thickness of the transparent resin layer 5 is preferably 20 μm or more and 200 μm or less. When the thickness of the transparent resin layer 5 is within this range, the strength of the decorative sheet 1 is improved, the printing workability when manufacturing the decorative sheet 1 is improved, and the manufacturing cost can be suppressed.
Further, the adhesive used to bring the pattern layer 4 and the transparent resin layer into close contact can be selected as an arbitrary material as an adhesive method, and there are laminating methods such as thermal laminating, extrusion laminating, and dry laminating. It can be selected from acrylic, polyester, polyurethane and other materials. Usually, a two-component curing type urethane-based material utilizing the reaction between isocyanate and polyol is desirable because of its cohesive force.

The laminating method is not particularly limited, but a method applying heat pressure, an extrusion laminating method, a dry laminating method, or the like is common. Further, in the case of applying the embossed pattern 5a, there are a method of later embossing the sheet once laminated by various methods by heat pressure, and a method of providing an uneven pattern on the cooling roll and embossing at the same time as extrusion laminating.
Further, a method of laminating the embossed pattern layer 4 and the transparent resin layer 5 at the same time as extrusion by heat or dry laminating can be used.

Further, when further laminating strength is required by the extrusion laminating method, an adhesive resin layer 5b may be provided between the transparent resin layer 5 and the adhesive. When the adhesive resin layer 5b is provided, the transparent resin layer 5 and the adhesive resin layer 5b are laminated by a coextrusion method. The adhesive resin layer 5b can be made by subjecting a resin such as polypropylene, polyethylene, or acrylic to acid modification. The thickness of the adhesive resin layer 5b is preferably 2 μm or more for the purpose of improving the adhesive strength.

(Top coat layer)
The topcoat layer 6 preferably contains a dispersant and inorganic fine particles. The content of the dispersant in the topcoat layer 6 is 0.01 part by mass or more and 3 parts by mass or less, more preferably 0.1 part by mass or more and 2 parts by mass with respect to 100 parts by mass of the resin material contained in the topcoat layer 6. It is less than a part.

Further, it is preferable that the inorganic fine particles of 0.1 part by mass or more and 30 parts by mass or less are blended with 100 parts by mass of the resin material which is the main component of the top coat layer 6. If it is less than 0.1 part by mass, it is difficult to obtain the effect of scratch resistance. On the other hand, if the amount is more than 30 parts by mass, there is a concern that the transparency may be impaired due to the light scattering action of the inorganic fine particles and that the cost may increase.

As the inorganic fine particles, for example, fine particles such as alumina, silica, boehmite, iron oxide, magnesium oxide, and diamond can be used. The average particle size of the inorganic fine particles is preferably 1 μm or more and 100 μm or less, and more preferably 1 μm or more and 30 μm or less.
Further, the resin composition of the top coat layer 6 is mainly composed of a resin material made of a curable resin, and it is preferable to use at least one of a heat-curable resin and a photo-curable resin as the curable resin, and the heat-curing is preferable. A mixture of the mold resin and the photocurable resin may be used. Further, the form of the curable resin is not particularly limited to water-based, emulsion, solvent-based and the like.

Further, as the thermosetting resin, it is preferable to use a two-component curable urethane-based thermosetting resin in consideration of workability, price, cohesive force of the resin itself, and the like. As the urethane-based thermosetting resin, a resin obtained by reacting an acrylic polyol with an isocyanate may be used.

Examples of the isocyanate include tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hydrogenated tolylene diisocyanate (HTDI), and hydrogenated xylylene diisocyanate. A curing agent such as isocyanate (HXDI), trimethylhexamethylene diisocyanate (TMDI), derivatives thereof (adduct, buretto, isocyanurate), and various prepolymers can be appropriately selected and used. Further, in consideration of weather resistance, it is preferable to use a curing agent based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI) having a linear molecular structure.

Further, as the photocurable resin, a polyester acrylate-based resin, an epoxy acrylate-based resin, a urethane acrylate-based resin, an acrylic acrylate-based resin, or the like can be appropriately selected and used. In particular, considering weather resistance (light resistance), it is preferable to use a urethane acrylate-based or acrylic acrylate-based resin. Further, as a curing method of the photocurable resin, it is preferable to cure with active energy rays such as ultraviolet rays and electron beams from the viewpoint of workability.

The mixture of the thermosetting resin and the photocurable resin includes a urethane resin (thermosetting resin) obtained by reacting an acrylic polyol and an isocyanate, and a urethane acrylate resin (photocurable resin). It is preferable to use a mixture of. By using this mixture, it is possible to improve the surface hardness, suppress the curing shrinkage, and improve the adhesion to the inorganic fine particles.

Further, in order to further improve the hardness of the surface of the decorative sheet 1, a resin that is cured by irradiation with ultraviolet rays or electron beams may be used as the top coat layer 6. Further, in order to improve the weather resistance, an ultraviolet absorber and a light stabilizer may be appropriately added to the top coat layer 6. Further, in order to impart various functions, a functional additive such as an antibacterial agent or an antifungal agent may be appropriately added to the top coat layer 6. The coating thickness of the top coat layer 6 is usually 2 μm or more and 10 μm or less.

(Primer layer)
As the material of the primer layer 7, basically the same material as that of the pattern layer 4 can be used. However, considering that it is applied to the back surface of the decorative sheet 1 and wound up in a web shape, silica, alumina, magnesia, titanium oxide, barium sulfate, etc. are used to avoid blocking and to improve the adhesion with the adhesive. Inorganic filler may be added. The coating thickness of the primer layer 7 is preferably 0.1 μm or more and 3.0 μm or less because the purpose is to ensure adhesion with the base material B. The primer layer 7 is necessary when the stretched film 2 has an inert surface such as an olefin-based material, but is not particularly necessary when the surface is active.

(Action, etc.)
(1) As described above, in the decorative sheet 1 of the present embodiment, the stretched film 2 formed by stretching and thinning a resin film containing a polyolefin resin as a main component is used as a base material for a decorative sheet. , Nonflammability and base material strength are improved.
(2) Further, by providing an adhesive layer 3 made of maleic acid-modified polypropylene, chlorinated polypropylene or maleic acid-modified chlorinated polypropylene between the stretched film 2 and the pattern layer 4, the stretched film 2 and the pattern layer 4 are provided. Adhesion can be improved.

Specific examples of the decorative sheet according to the present invention will be described below. The present invention is not limited to these examples.
(Example 1)
0.5 parts by mass of a hindered amine-based light stabilizer (BASF's "Kimasorb 944") and a benzotriazole-based ultraviolet absorber (BASF's "" Chinubin 328 ") 0.5 parts by mass was mixed. The obtained mixture was formed into a film using a melt extruder and uniaxially stretched to form a stretched film having a thickness of 30 μm.

Next, 500 parts by mass of butyl acetate was mixed with 100 parts by mass of the adhesive layer resin A shown in Table 1 and dissolved. The dissolved coating liquid was applied to a stretched film at a thickness of 2 g / m ² and dried to form an adhesive layer. Further, a pattern printing was applied to the surface of the adhesive layer to form a pattern layer. The pattern layer is a two-component urethane ink (“V180” manufactured by Toyo Ink Co., Ltd.) and a hindered amine-based light stabilizer (“Kimasorb 944” manufactured by BASF) with respect to 100 parts by mass of the binder resin content of the ink. It was formed by using ink added in an amount of 5 parts by mass. In addition, a primer layer was formed on the back surface of the stretched film. The primer layer was formed by printing a two-component urethane ink similar to the pattern layer.

Subsequently, a hindered amine-based light stabilizer (BASF's "Kimasorb 944") was added to 100 parts by mass of a crystalline polypropylene resin (pentad fraction: 97.8%, molecular weight distribution: 2.3, MFR: 18 g / 10 min). ) 0.5 part by mass and 0.5 part by mass of a benzotriazole-based ultraviolet absorber (“Tinubin 328” manufactured by BASF) were mixed. The obtained mixture and the polyethylene-based easy-adhesive resin were co-extruded using a melt extruder to form a laminate of a transparent resin layer having a thickness of 60 μm and an adhesive resin layer having a thickness of 10 μm.

Next, a dry laminating adhesive (“Takelac A540” manufactured by Mitsui Chemicals, Inc., coating amount: 2 g / m ² ) was applied to the surface of the decorative sheet base material on which the pattern layer was formed. Subsequently, the pattern layer surface of the base material for a decorative sheet coated with an adhesive and the transparent resin layer of the above-mentioned laminate were bonded by an extrusion laminating method, and bonded via the adhesive resin layer of the above-mentioned laminate. Further, the surface of the sheet formed by laminating on the transparent resin layer side is pressed with a mold roll for embossing to form an embossed pattern, and then a two-component curable urethane top is applied on the embossed pattern surface. A coat (“W184” manufactured by DIC Graphics) was applied at a coating amount of 3 g / m ² to obtain a decorative sheet 1 having the same configuration as the decorative sheet shown in FIG.

(Examples 2 to 10)
In Examples 2 to 10, the adhesive layer was formed by using the adhesive layer resins B to J shown in Table 1. Other than that, the same configuration as in Example 1 was used, and decorative sheets 2 to 10 were obtained. Table 2 shows the configurations of the decorative sheets 1 to 10. Table 2 also describes the evaluation.

<Performance evaluation of decorative sheets 1 to 10>
The performance of the decorative sheets 1 to 10 was evaluated.
[Base strength]
The stretched film (base material for decorative sheet) used for the decorative sheets 1 to 10 was pulled by a Tensilon universal material tester at a tensile speed of 50 mm / min, and the elastic modulus was measured. When the elastic modulus was 1000 MPa or more and less than 2000 MPa, the substrate strength was evaluated as good, and is indicated by a circle in the table. On the other hand, when the elastic modulus was less than 1000 MPa, the strength of the base material was evaluated as poor, and is indicated by a cross in the table.

[Non-flammable test]
Decorative sheets 1 to 10 were attached to a metal plate, and a heat generation test was carried out using an ISO5660-1 compliant cone calorie meter tester. Non-combustibility is judged by whether or not the provisions of Article 108-2, Items 1 and 2 of the Building Standards Act Enforcement Ordinance are satisfied. If not satisfied, it is indicated by a cross.

[Interlayer adhesion test]
The interlayer adhesion test is a test for evaluating the adhesion (adhesiveness) between the transparent resin layer and the stretched film. The interlayer adhesion test was carried out according to JIS K6854-2. When the measured adhesion was within the JIS K6854-2 standard, it was evaluated that the interlayer adhesion was very good, and it is indicated by a circle in the table. On the other hand, when the measured adhesion was out of the JIS K6854-2 standard, it was evaluated that the interlayer adhesion was poor, and it was indicated by a cross in the table. However, if the measured adhesion is out of the JIS K6854-2 standard but at a level that does not hinder practical use, the interlayer adhesion is evaluated as good and is indicated by a Δ in the table.

[Solubility of adhesive layer resin]
The solubility of the adhesive layer resin was evaluated by whether or not the coating liquid dissolved during production reaggregates. When there was no reaggregation, the solubility was evaluated to be very good, and it is indicated by a circle in the table. In addition, when there was reaggregation but it was at a level that could be used, the solubility was evaluated as good, and it is indicated by Δ in the table. When there was reaggregation, the solubility was evaluated as poor, and it was indicated by a cross in the table.

As shown in Table 2, each evaluation of the decorative sheets 1 to 10 had no problem and was a good result.
(Examples 11 to 18)
In Examples 11 to 18, the adhesive layer was formed by using the adhesive layer resins KR shown in Table 3. Other than that, the same configuration as in Example 1 was used, and decorative sheets 11 to 18 were obtained. Table 4 shows the configurations of the decorative sheets 11 to 18.

<Performance evaluation of decorative sheets 11-18>
The performance of the decorative sheets 11 to 18 was evaluated in the same manner as the decorative sheets 1 to 10. The evaluation results are shown in Table 4.
As shown in Table 4, the decorative sheets 11 and 15 had slightly lower adhesion than the decorative sheets 1 to 10. This is because the amount of maleic acid-modified polypropylene and maleic acid-modified chlorinated polypropylene contained in the adhesive layer is small, so that the effect of adhesion is not sufficiently exhibited.

The decorative sheets 12 and 16 had slightly lower solubility of the adhesive layer resin than the decorative sheets 4 to 10. This is because the amount of acid modification of maleic acid-modified polypropylene and maleic acid-modified chlorinated polypropylene is large, so that the solubility is slightly lowered.
The decorative sheets 13 and 17 had slightly lower adhesion than the decorative sheets 1 to 10. This is because the chlorine content is low and the effect of adhesion is not sufficiently exhibited.

The decorative sheets 14 and 18 had slightly lower adhesion than the decorative sheets 1 to 10. This is because the chlorine content is high and the effect of adhesion is not sufficiently exhibited.
Regarding the decorative sheets 11 to 18, although some items had slightly lower performance, they were at a level that would not hinder practical use.

(Comparative Examples 1 to 6)
In Comparative Examples 1 to 6, the adhesive layer was formed by using the adhesive layer resins S to X shown in Table 5. Other than that, the same configuration as in Example 1 was used, and decorative sheets 19 to 24 were obtained. Table 6 shows the configurations of the decorative sheets 19 to 24.

The decorative sheets 19, 21 and 23 had poor adhesion. This is because the molecular weight of the adhesive layer resin is small and the effect of adhesion is not exhibited.
The decorative sheets 20, 22, and 24 had poor solubility of the adhesive layer resin. This is because the molecular weight of the adhesive layer resin is too large and the solubility is deteriorated.

(Comparative Examples 7 and 8)
In Comparative Examples 7 and 8, a non-stretched film was used as a base material instead of a stretched film. Further, the non-stretched film and the pattern layer were bonded together without providing the adhesive layer. Other than that, the same configuration as in Example 1 was used, and decorative sheets 25 and 26 were obtained. The configurations of the decorative sheets 25 and 26 are shown in Table 7.

<Performance evaluation of decorative sheets 25 and 26>
The performance of the decorative sheets 25 and 26 was evaluated in the same manner as the decorative sheets 1 to 10. The evaluation results are shown in Table 7.
As shown in Table 7, the decorative sheet 25 had insufficient strength of the base material for the decorative sheet. This is because the unstretched raw fabric was made thin. On the other hand, the nonflammability test of the decorative sheet 26 was out of the standard. This is because the thickness of the base material for the decorative sheet is 60 μm.

1 ... Decorative sheet 2 ... Stretched film 3 ... Adhesive layer 4 ... Pattern layer 5 ... Transparent resin layer 5a ... Embossed pattern 5b ... Adhesive resin layer 6 ... Top coat layer 7 ... Primer layer B ... Base material

Claims (5)

At least an adhesive layer and a pattern layer are laminated in this order on a uniaxially stretched or biaxially stretched stretched film, and the adhesive layer is made of maleic acid-modified polypropylene or chlorinated polypropylene having a weight average molecular weight of 60,000 or more and 100,000 or less. A decorative sheet containing at least one of maleic acid-modified chlorinated polypropylene and the stretched film made of a polyolefin resin . The decorative sheet according to claim 1, wherein the amount of acid modification of at least one of the maleic acid-modified polypropylene and the maleic acid-modified chlorinated polypropylene is 1.0% by mass or more and 2.0% by mass or less. The decorative sheet according to claim 1 or 2, wherein the chlorine content of at least one of the chlorinated polypropylene and the maleic acid-modified chlorinated polypropylene is 20% by mass or more and 30% by mass or less. The requirements described in Article 108-2, No. 1 and No. 2 of the Building Standards Act Enforcement Ordinance are satisfied in the heat generation test by the cone calorie meter tester conforming to ISO5660-1 in the state of being bonded to the nonflammable base material. The decorative sheet according to any one of claims 1 to 3 , which is a non-combustible material to be satisfied. A non-combustible decorative board provided with the decorative sheet according to any one of claims 1 to 4 on the surface of a non-combustible base material.

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