JP2000052500A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative sheet wherein a surface resin layer comprising an olefinic resin is provided on the surface of a base material sheet, to improve the adhesion of the decorative layer provided on the base material sheet and the surface resin layer provided thereon and to prevent the generation of an environmental problem. SOLUTION: In a decorative sheet 1 wherein a decorative layer and a transparent olefinic resin layer 4 are successively laminated on a base material sheet 2, an ethylene/methyl methacrylate copolymer is compounded with the transparent olefinic resin layer 4. Further, an org. ultraviolet absorber having a hydroxyl group in its molecule may be added to at least the outermost surface transparent olefinic resin layer 4 and a surface protective layer comprising a resin having an isocyanate group in its molecule may be formed on the surface of the transparent olefinic resin layer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative sheet used for interior decoration of buildings, surface decoration of fittings, vehicle interior decoration, and the like.

[0002]

2. Description of the Related Art A decorative sheet in which a surface resin layer made of a thermoplastic resin is provided on the surface of a base sheet is conventionally known. In such a decorative sheet, a vinyl chloride resin is used as the thermoplastic resin. Has been commonly used.

[0003] This type of decorative sheet has drawbacks such as insufficient heat resistance and poor surface stain resistance due to bleeding of a plasticizer. In recent years, a decorative sheet that does not use a vinyl chloride resin has been strongly demanded.

For example, JP-A-6-79830 discloses that a pattern ink layer, an adhesive layer, and a thermoplastic transparent elastomer film layer are sequentially laminated on a surface of a base sheet made of an olefin resin having a masking property. At the same time, an embossed decorative sheet provided with an embossed pattern by embossing has been proposed, and JP-A-6-79850 discloses that a pattern ink layer is provided on a base sheet made of an olefin resin having a masking property. There has been proposed a decorative wiping sheet in which an embossed recess is provided at the same time as the system transparent resin is eluted and laminated, and the embossed recess is filled with a coloring ink.

[0005]

However, the above-mentioned decorative sheet has a problem that the adhesive strength between the decorative layer made of the pattern ink and the surface resin layer is low, and the decorative sheet is easily peeled off therefrom. Further, when the surface resin layer is laminated by the extrusion coating method, the olefin-based resin in a molten state tends to have poor adhesion to the base sheet and the decorative layer. In addition, these olefin resins have insufficient weather resistance (light resistance) as an interior or exterior sheet for building materials. Therefore, in order to improve the weather resistance, an attempt has been made to add an organic ultraviolet absorbent such as a benzotriazole-based resin having excellent visible light transparency to the polyolefin-based resin of the surface resin layer. However, such organic UV absorbers have poor compatibility with polyolefin resins, and even when added, they bleed out to the surface during exposure to sunlight and were lost, or Even if a decorative sheet is subjected to thermal processing such as embossing, it will bleed out and be lost. Therefore, even if an ultraviolet absorber was added, the effect was not sufficiently exhibited.

The present invention has been made in order to solve the above-mentioned drawbacks of the prior art, and has good adhesion between a surface resin layer and a decorative layer, and has sufficient weather resistance as a decorative sheet for building materials. An object of the present invention is to provide a decorative sheet that does not use PVC.

[0007]

The present invention provides a decorative sheet comprising (1) a decorative sheet and an olefin-based transparent resin layer sequentially laminated on a base sheet, wherein the olefin-based transparent resin layer has A decorative sheet comprising a methyl methacrylate copolymer, (2) a decorative sheet comprising a base sheet, on which a decorative layer and an olefin-based transparent resin layer are sequentially laminated; (3) The decorative sheet, wherein the transparent resin layer has a two-layer structure, and a layer located on the decorative layer side of the two layers is mixed with an ethylene-methyl methacrylate copolymer. (1) The decorative sheet according to (1) or (2), wherein an organic ultraviolet absorber having a hydroxyl group in a molecule is added to at least the outermost olefin-based transparent resin layer, and the olefin-based transparent resin layer is provided. Decorative sheet, obtained by forming a surface protective layer made of a resin having an isocyanate group in a molecule on the surface in which the gist of the.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. As shown in FIG. 1, the decorative sheet 1 of the present invention has a configuration in which a decorative layer 3 and an olefin-based transparent resin layer 4 are sequentially laminated on a base sheet 2. In FIG. 1, reference numeral 5 denotes a surface protective layer provided as needed.

As the base sheet 2, (a) an olefin-based resin film or sheet (hereinafter referred to as a sheet in the present invention also includes a film), or (b) a fibrous sheet is used.

(A) As a sheet preferably used for the olefin-based resin sheet, a sheet comprising a high-density polyethylene resin, an elastomer, a colorant, and an inorganic filler is exemplified. According to the sheet, the performance required as a decorative sheet, that is, thermoformability comparable to polyvinyl chloride, creep deformation resistance, cold bending strength, organic solvent resistance, elongation at break, impact strength, moderate Those satisfying the flexural modulus and easy adhesion can be obtained.

As the high-density polyethylene, it is more preferable to use a polyethylene having a specific gravity of 0.94 to 0.96 and having a high degree of crystallinity obtained by a low-pressure method and having a small number of branched structures.

[0012] Examples of the elastomer include a diene rubber, a hydrogenated diene rubber, and an olefin elastomer. The amount of the elastomer added is 10 to 60% by weight, preferably 30% by weight in the base sheet.
It is about. If the amount of the elastomer is less than 10% by weight, the change in elongation at constant load becomes too steep,
Elongation at break and impact resistance decrease, and if it is higher than 60%, transparency, weather resistance and creep resistance decrease. By the addition of the elastomer, the flexibility, impact resistance, easy adhesion and the like when formed as a base sheet can be improved.

A thermoplastic elastomer can be used for the olefin resin sheet. The following six types of thermoplastic elastomers are available.

A simple blend of (A) a thermoplastic elastomer as a soft segment and (B) a crystalline olefin resin as a hard segment.

Specifically, as the olefin resin, polyethylene (high-density, medium-density, or low-density), ethylene-propylene copolymer, ethylene-butene-1 copolymer, polypropylene (isotactic or synd Resins such as propylene / butene-1 copolymer, polybutene-1, butene-1 / propylene / ethylene copolymer, butene-1 / hexene-1 / octene-1 tricopolymer, and polymethylpentene They may be used alone or in combination of two or more.

The thermoplastic elastomer includes various rubbers, and examples of the rubbers include diene rubbers and hydrogenated diene rubbers. Of these, hydrogenated diene rubbers are preferred. The thermoplastic elastomer will be described later.
And the like.

The hydrogenated diene rubber is obtained by adding a hydrogen atom to at least a part of the double bond of the diene rubber, and has a role of suppressing crystallization of the olefin resin and increasing flexibility and transparency. There is. In general, when a diene rubber is added to an olefin resin, the weather resistance and heat resistance are lower than that of the olefin resin without a diene rubber due to the double bond of the diene rubber. By saturating the bond with hydrogen, the olefin-based resin becomes favorable without deterioration in weather resistance and heat resistance.

As the diene rubber, isoprene rubber,
Butadiene rubber, butyl rubber, propylene / butadiene rubber, acrylonitrile / butadiene rubber, acrylonitrile / isoprene rubber, styrene / butadiene rubber, and the like. For the purpose of the present invention, styrene-butadiene rubber is particularly preferred.

The amount of the olefin resin 100
It is about 1 to 90 parts by weight of the thermoplastic elastomer based on parts by weight. If the amount is less than 1 part by weight, the elasticity, elongation, and impact resistance due to the addition of rubber are insufficient, and cracks and cracks are likely to occur during bending such as V-cutting and drawing. Also, 9
If the amount exceeds 0 parts by weight, the elasticity and the elongation percentage become too large, and the examination upon printing becomes poor, which is not preferable.

(A) The number average molecular weight Mn is 25,000 or more, and the ratio Mw / M of the weight average molecular weight Mw to the number average molecular weight Mn as described in JP-B-6-23278.
10 to 90% by weight of boiling heptane-soluble polypropylene (soft segment) with n ≦ 7 and (B) 90 to 10% by weight of boiling heptane-insoluble polypropylene (hard segment) having a melt index of 0.1 to 4 g / 10 min. Soft polypropylene consisting of a mixture.

As described in JP-B-53-21021, (A) an olefin polymer (crystalline polymer) such as polyethylene, polypropylene, or polymethylpentene is used as a hard segment, and (B) partially crosslinked ethylene An olefin elastomer obtained by using a soft segment of a monoolefin copolymer rubber such as a propylene copolymer rubber or an unsaturated ethylene / propylene / nonconjugated diene terpolymer rubber, and uniformly blending and mixing these. (A) and (B) are (B) / (A) = 50 / 50-9
Mix at a ratio of 0/10 (weight ratio).

As described in JP-B-53-34210, (A) an uncrosslinked monoolefin copolymer rubber (soft segment), (B) a crystalline olefin copolymer (hard segment) and a crosslinking agent are mixed. An olefin elastomer obtained by heating and applying a shear stress to dynamically partially crosslink. The above (A) and (B) are (B) / (A)
= 60/40 to 80/20 (weight ratio).

(A) isotactic polypropylene, propylene / ethylene copolymer, propylene / butene-1 as described in JP-B-56-15741 and the like.
A peroxide-decomposable olefin polymer (hard segment), which mixes with peroxides such as copolymers and reduces the molecular weight when heated and increases fluidity, and (B) ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene (C) a peroxide-crosslinked monoolefin copolymer rubber (soft segment), which is crosslinked to reduce fluidity by being mixed with a peroxide such as a terpolymer rubber;
A peroxide non-crosslinked hydrocarbon rubber (soft segment and fluidity-modifying component) that does not crosslink even when heated and mixed with peroxides such as polyisobutylene and butyl rubber, and that does not crosslink, and (D) paraffinic or naphthene An olefin elastomer obtained by mixing a mineral oil-based softening agent such as an oil or an aromatic oil and dynamically heat-treating the mixture in the presence of an organic peroxide. (A), (B), (C) and (D) are (A) 90 to 40 parts by weight, (B) 10 to 60 parts by weight, (C)
And (D) have a compounding ratio of 5 to 100 parts by weight.

An olefin elastomer comprising an ethylene / styrene / butylene terpolymer as described in JP-A-2-139232.

Ethylene / propylene / butene copolymer; The ethylene / propylene / butene copolymer resin serving as the base sheet may be any one of three types of structural isomers of 1-butene, 2-butene and isobutylene. Can also be used. The copolymer is preferably a random copolymer which contains a part of an amorphous part and becomes a thermoplastic elastomer.

Preferred specific examples of the ethylene / propylene / butene copolymer include the following (a) to (c).

(A) Those described in JP-A No. 9-111055. This is the three of ethylene, propylene and butene.
It is a random copolymer based on the original copolymer. The weight ratio of the monomer components is 90% by weight or more of propylene. Melt flow rate is 1-50g at 230 ℃ and 2.16kg
/ 10 minutes is preferred. Then, a transparent nucleating agent containing a phosphate aryl ester compound as a main component in an amount of 0.01 to 100 parts by weight based on 100 parts by weight of such a ternary random copolymer.
50 parts by weight, fatty acid amide having 12 to 22 carbon atoms 0.00
It is obtained by melting and kneading 3 to 0.3 parts by weight.

(B) Those described in JP-A-5-77371. This is the three of ethylene, propylene and 1-butene.
An original copolymer, which is obtained by adding 80 to 0% by weight of crystalline polypropylene to 20 to 100% by weight of an amorphous polymer having a propylene component content of 50% by weight or more.

(C) Those described in JP-A-7-316358. This is a terpolymer of ethylene, propylene and 1-butene, wherein the content of propylene and / or 1-butene is 50% by weight or more.
Composition 1 in which 80 to 0% by weight of a crystalline polyolefin such as isotactic polypropylene is mixed with 00% by weight.
N-acylamino acid amine salt, N
-0.5% by weight of an oil gelling agent such as an acyl amino acid ester is added.

The base sheet 2 is preferably colored by adding a colorant comprising a pigment or a dye. The coloring is colored transparent or opaque (concealing) coloring depending on the application. The color of the base sheet 2 is generally opaque because it can cover the surface of the adherend.

Examples of the coloring agent include inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine blue, cobalt blue, titanium yellow, carbon black, and the like, isoindolino, Hanzai yellow A, quinacridone, permanent red 4R, phthalocyanine blue and the like. Organic pigments or dyes, metal pigments such as aluminum and pearls, mica coated with titanium dioxide, pearlescent pigments made of foil powder such as basic zinc carbonate and the like are used.

An inorganic filler may be added to the base sheet 2 if necessary. As the inorganic filler, powders such as calcium carbonate, barium sulfate, clay, and talc are contained in the base sheet in an amount of about 5 to 60% by weight, preferably 30% by weight.
To some extent. If the amount is less than 5% by weight, the creep deformation resistance and the adhesion will be reduced. If it is more than 60% by weight, the elongation at break and the impact resistance will be reduced.

Further, an ultraviolet absorber, a light stabilizer, a heat stabilizer, an antioxidant, an antistatic agent, a flame retardant, a foaming agent, and the like are added to the base sheet 2 as required.

The ultraviolet absorber and the light stabilizer are for imparting good weather resistance (light resistance) to the resin, and the amount of the ultraviolet absorber and the light stabilizer is usually 0.5 to 1 for both the ultraviolet absorber and the light stabilizer.
It is about 0% by weight. Generally, it is preferable to use an ultraviolet absorber and a light stabilizer in combination.

Organic substances such as benzotriazole, benzophenone, salicylate, etc.
Alternatively, inorganic substances such as zinc oxide, cerium oxide, and titanium oxide having a diameter of 0.2 μm or less can be used.

As the light stabilizer, bis- (2,2,6,
Hindered amine radical scavengers such as 6-tetramethyl-4-piperidinyl) sebacate and radical scavengers such as piperidine radical scavengers can be used.

The heat stabilizer is a known heat stabilizer such as a phenol type, a sulphite type, a phenylalkane type, a phosphite type, an amine type, etc., and is used for improving the prevention of deterioration such as thermal discoloration during thermal processing. Used.

Powders such as aluminum hydroxide and magnesium hydroxide are used as the flame retardant, and these are added when it is necessary to impart flame retardancy.

The olefin resin sheet used for the base sheet 2 is obtained by forming a blend of the above materials into a sheet by a conventional method such as a calendering method.

When an olefin resin sheet is used as the base sheet 2, its thickness is about 30 to 200 μm, more preferably about 50 to 100 μm. As the olefin-based resin sheet, any of a stretched sheet and an unstretched sheet can be used, but the unstretched sheet has good formability such as V-cut processing.

The (b) fibrous sheet used for the base sheet 2 may be a sheet made of paper, woven fabric, or nonwoven fabric having a basis weight of about 50 to 150 g / m ² . Its thickness can be selected from the range of about 50 to 300 μm.

The fibrous material constituting the fibrous sheet is an organic synthetic fiber such as cellulose pulp, hemp, cotton, nylon or the like, or an artificial fiber such as asbestos, glass, quartz, carbon, potassium titanate or the like. Is mentioned. The fibrous material can be subjected to flame retardant treatment by mixing a flame retardant such as a phosphoric acid compound such as aziridinyl phosphine oxide. Incidentally, the fibrous base material sheet using cellulose pulp fiber is a so-called "paper", specifically,
Fine paper, kraft paper, Japanese paper and the like can be mentioned.

In the present invention, the decorative layer 3 and the olefin-based transparent resin layer 4 are sequentially laminated on such a base sheet 2.

The decorative layer 3 is formed on the surface of the base sheet 2 by pattern printing, coloring printing, or the like. The decorative layer 3 is specifically a colored (transparent or opaque) pattern or solid printing by adding a pigment, and uses a known printing method such as gravure printing, offset printing, silk screen printing, or transfer printing from a transfer sheet. , Ink or paint (hereinafter simply referred to as ink).

The pattern of the decoration layer 3 includes a wood grain pattern, a stone grain pattern, a cloth grain pattern, a squeezed pattern, a geometric figure, characters, symbols, and the like. The decoration layer 3 may be provided on the entire surface of the surface of the base sheet 2 or may be provided partially.

As the ink used for the decorative layer 3, as a binder, chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polyester, polyurethane, acrylic, vinyl acetate, vinyl chloride-vinyl acetate copolymer, cellulose resin, etc. And one obtained by mixing one or more kinds thereof and adding a known pigment as described above to the mixture. When printing directly on an olefin-based resin sheet, it is preferable to use chlorinated polyolefin, polyurethane, or the like as a binder in terms of adhesiveness, but the olefin-based resin sheet is subjected to an easy adhesion treatment such as a corona discharge treatment or a plasma discharge treatment. Alternatively, if a layer is formed by appropriately selecting an easy-adhesion primer, the decorative layer 3 can be provided on the base sheet 2 with sufficient adhesiveness even if other binders are used. The easy-adhesion primer is selected from acrylic, vinyl chloride / vinyl acetate copolymer, polyester, urethane, chlorinated polypropylene, chlorinated polyethylene and the like. The ink used for the decoration layer 3 is preferably a urethane-based high-temperature reaction type (150 to 250 ° C.), and the use of such an ink makes it unnecessary to apply an adhesive described later.

Olefin transparent resin layer 4 in the present invention
Is mainly composed of an olefin-based resin, and the olefin-based transparent resin layer 4 needs to be blended with an ethylene-methyl methacrylate copolymer.
It is preferred to be blended by weight%.

In the present invention, the ethylene-methyl methacrylate copolymer is blended in the olefin-based transparent resin layer 4 containing the olefin-based resin as a main component at the above-mentioned ratio, whereby
The adhesion between the decorative layer 3 and the olefin-based transparent resin layer 4 can be improved. If the amount of the ethylene-methyl methacrylate copolymer is less than 5% by weight, the adhesion cannot be sufficiently improved, which is not preferable. On the other hand, if it exceeds 40% by weight, the initial adhesion is good, but when exposed to ultraviolet rays of sunlight, the adhesion deteriorates with time. In addition, the heat resistance of the olefin-based transparent resin layer 4 is significantly reduced.
Further, when the surface protective resin layer 5 is not provided, the solvent resistance and chemical resistance of the surface are undesirably reduced.

The ethylene / methyl methacrylate copolymer used in the present invention can be obtained by copolymerizing ethylene and methyl methacrylate. In copolymerizing ethylene and methyl methacrylate, the content of the ethylene component is preferably from 10 to 90 mol%. If the content of the ethylene component is less than 10% by weight, the bending processability of the transparent resin layer 4 becomes insufficient, and the transparent resin layer 4 is not easily broken at the time of bending. If it exceeds 90% by weight, the effect of improving the adhesion is not sufficiently exhibited, which is not preferable. Incidentally, methyl acrylate may be used instead of methyl methacrylate.

In the present invention, the olefin resin used for the olefin transparent resin layer 4 includes polyethylene, ethylene / propylene copolymer, ethylene / butene-1 copolymer, polypropylene, propylene / butene-1 copolymer, Polybutene-1, butene-1-propylene-ethylene copolymer, butene-1-hexene-1-octene
Olefin resins such as 1,3 copolymer and polymethylpentene, and the olefin thermoplastic elastomers exemplified as the material of the base sheet 2 can be used. These resins may be used alone or in combination of two or more.

The olefin-based transparent resin layer 4 is preferably used in the description of the olefin-based thermoplastic elastomer, and is a colorless compound having a complex three-dimensional structure, comprising a mixed system of isotactic polypropylene and atactic polypropylene. Or, it is a colored transparent soft polypropylene resin. If a soft polypropylene resin having the above composite three-dimensional structure is used, the performance required as a decorative sheet, namely, creep deformation resistance, organic solvent resistance, elongation at break, impact strength, moderate flexural modulus, transparency In addition, even if heating and cooling accompanying embossing and the like are applied, whitening and turbidity due to recrystallization do not occur, and a material having satisfactory weather resistance can be obtained.

The colorless or colored transparent soft polypropylene-based resin having a composite steric structure, which is composed of a mixture of isotactic polypropylene and atactic polypropylene, is specifically (A) (a) magnesium, titanium, halogen, or the like. A solid catalyst component containing an atom and an electron donor as essential components, (b) an organoaluminum compound, and (c) a general formula (1)

Embedded image (Wherein R ¹ is an alkyl group having 1 to 20 carbon atoms, R ² is a hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group or a nitroso group, m
Is an integer of 1 to 6, and n is an integer of 0 or 1 to (6-m).) Is obtained by polymerizing propylene in the presence of a catalyst comprising a combination of an alkoxy group-containing aromatic compound represented by the formula: Has a number average molecular weight (Mn) of 25,000
Boiling heptane-soluble polypropylene (atactic polypropylene) having a weight average molecular weight (Mw) and a number average molecular weight (Mn) ratio (Mw / Mn) of 7 or less
10 to 90% by weight and (B) the melt index is 0.1%.
90 to 10% by weight of boiling heptane-insoluble polypropylene (isotactic polypropylene) of 1 to 4 g / 10 minutes
And a soft polypropylene resin composition comprising:

The soft polypropylene resin composition has an elongation at break (T _b ) of 400% or more, preferably 500 to 7%.
Residual elongation (PS ₁₀₀ ) after 100% and 100% elongation is 80
%, Preferably 50 to 75%, and the stress at break (M
_B ) and the stress at yield (M _Y ) (M _B / M _Y ) are 1.
It is desirably 0 or more, preferably in the range of 1.5 to 3.5.

In the above soft polypropylene resin composition, the atactic polypropylene as the component (A) is soluble in boiling heptane and has a number average molecular weight (M
n) is 25,000 or more, preferably 30,000 to 6
Weight average molecular weight (Mw) in the range of 000
And a number average molecular weight (Mn) having a ratio Mw / Mn of 7 or less, preferably 2 to 6. This M
If the n is less than 25,000 or the Mw / Mn ratio exceeds 7, the effect of contributing to the mechanical properties of the atactic polypropylene in the obtained resin is not sufficiently exhibited, and the stress at break of the obtained resin ( Undesirably, the ratio of (M _B ) to the stress at yield (M _Y ) is less than 1.0, or the residual elongation (PS ₁₀₀ ) after 100% elongation exceeds 80%.

The atactic polypropylene as the component (A) may be a homopolymer of propylene, or may have a propylene unit content of at most 40% by weight, preferably at most 30% by weight, and other α-olefins having 2 to 30 carbon atoms. It may be a propylene copolymer containing an olefin unit. Also, this atactic polypropylene may be used alone or in combination of two or more. The atactic polypropylene of the component (A) can be prepared by a known method (Japanese Patent Application Laid-Open No.
No. 3-243106).

In the above soft polypropylene resin composition, as the component (B), a melt index (MI)
However, boiling heptane-insoluble crystalline isotactic polypropylene of 0.1 to 4 g / 10 min is used. If the melt index is less than 0.1 g / 10 minutes, the melting properties are low, and sheet forming becomes difficult. If the melt index exceeds 4 g / 10 minutes, the mechanical strength becomes insufficient and V-cutting may not be performed well. There is.

The isotactic polypropylene of the component (B) may be a propylene homopolymer having isotactic stereoregularity, or a copolymer of propylene having the stereoregularity with another α-olefin. It may be a copolymer. The α-olefin has 2 to 2 carbon atoms.
8, for example, ethylene, butene-1, pentene-
1, heptene-1, octene-1 and the like are preferable, and among them, ethylene and butene-1 are preferable. In addition, as the copolymer, the above-mentioned other α-olefin unit is usually 40 units.
A block copolymer or a random copolymer containing not more than 30% by weight, preferably not more than 30% by weight is used.

Preferred examples of the isotactic polypropylene as the component (B) include propylene homopolymer and 1 to 30% by weight of ethylene unit, preferably 3 to 30% by weight.
A random copolymer or block copolymer of propylene and ethylene containing 25% by weight is exemplified. The production of such an isotactic polypropylene can be performed in the same manner as the production of a conventional crystalline polypropylene.

In the above soft polypropylene resin composition, the isotactic polypropylene of the component (B) may be used alone or in combination of two or more. Further, the atactic polypropylene of the component (A) and the isotactic polypropylene of the component (B)
When the content of the component (A) is 10 to 90% by weight, preferably 2%
It is used in such a ratio that the content of the component (B) is 5 to 80% by weight, and 90 to 10% by weight, preferably 75 to 20% by weight. When the content of the component (A) is less than 10% by weight, the stress at yield (M _Y ) of the resin becomes too large, and the ratio M _B between the stress at break (M _B ) and the stress at yield (M _Y ) is obtained. / M
_{The Y} ratio becomes less than 1.0, and the residual elongation (PS ₁₀₀ ) after 100% elongation becomes larger than 80%. Meanwhile in the content is too small at break exceeds 90 wt% stress (M _B), wherein M _B / M _Y ratio is less than 1.0,
Moreover, there is a possibility that the mechanical strength is reduced. Further, by increasing the ratio of the component (B), the Young's modulus of the obtained soft polypropylene increases. A particularly preferred ratio of the component (A) to the component (B) is 1: 1.

Various additives such as the above-mentioned ultraviolet absorber, light stabilizer, filler, flame retardant, foaming agent and the like can be added to the olefin resin as required.

The adhesion between the decorative layer 3 and the olefin-based transparent resin layer 4 is prevented from deteriorating with time due to ultraviolet rays, and the weather resistance required as a decorative sheet for interior building materials, ie, a carbon arc lamp type sunshine weather o. 1000 of meters
Even after irradiation for a period of time (black panel 63 ° C., rainfall time), in order to provide sufficient adhesion strength as a decorative sheet and further improve weather resistance adhesion, the olefin-based transparent resin layer 4 should have an ultraviolet absorber, more preferably an ultraviolet absorber. It is advisable to add both an ultraviolet absorber and a light stabilizer.

In the present invention, an organic compound having a hydroxyl group (OH group) in a molecule is used as an ultraviolet absorber in view of transparency to visible light and prevention of bleed out.
For example, 2 {(2'-hydroxy {3 ', 5'-di} t
tert-butylphenyl) {5} chlorobenzotriazole, 2 {(2′-hydroxy {3′-tert-butyl} 5′-methylphenyl)} 5} chlorobenzotriazole, 2} (2′-hydroxy} 3 ′ -Tert-amyl {5'-isobutylphenyl) {5} chlorobenzotriazole, 2 {(2'-hydroxy {3'-isobutyl} 5'-methylphenyl) {5} chlorobenzotriazole, 2} (2 '2'-hydroxyphenyl-5-chlorobenzotriazole-based ultraviolet absorbers such as -hydroxy {3'-isobutyl-5'-propylphenyl) -5-chlorobenzotriazole, and 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, etc. Benzotrial-based UV absorbers such as 2'-hydroxyphenylbenzotriazole-based UV absorbers; 2,2'-dihydroxy-4-methoxybenzophenone;2,2'-dihydroxy-4,4'-dimethoxybenzophenone; , 2 ',
2, such as 4,4'-tetrahydroxybenzophenone
2′─dihydroxybenzophenone UV absorbers,
2-hydroxy-4-methoxybenzophenone, 2,4
Benzophenone ultraviolet absorbers such as 2-hydroxybenzophenone ultraviolet absorbers such as dihydroxybenzophenone, and salicylate ultraviolet absorbers such as phenyl salicylate and 4-tert-butylphenylphenyl salicylate are used. In addition, a reactive ultraviolet absorber in which an acryloyl group or a methacryloyl group is introduced into a benzotriazole skeleton is also used. The amount of these ultraviolet absorbers is usually about 0.1 to 10% by weight.

Further prevention of deterioration of each layer due to ultraviolet rays,
In order to improve weather resistance, it is preferable to add a radical scavenger as another light stabilizer. Examples of the radical scavenger include bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate and bis {(N-methyl-2,2,6,6-tetramethyl-4-piperidinyl)
Sebacate, a hindered amine radical scavenger such as a compound disclosed in Japanese Patent Publication No. 4-82625, a piperidyl radical scavenger, and the like are used. When a light stabilizer consisting of a hindered amine radical scavenger is added to the polyolefin, not only the polyolefin resin, but also a layer of the ink layer adjacent to the polyolefin resin sheet, a layer of the adhesive layer and the like, a polyurethane resin, a polyolefin resin, Use of a resin containing no chlorine atom in the molecule, such as a polyamide resin, is favorable in terms of improving weather resistance. If resins containing chlorine atoms in molecules such as vinyl chloride-vinyl acetate copolymers and chlorinated polyolefins are used, hydrogen chloride is generated from these resins by the action of ultraviolet light or heat, resulting in hydrogen chloride, which is a hindered amine radical. Since it reacts with the scavenger to deactivate or inhibit its action, the weather resistance is not sufficiently improved.

The olefin-based transparent resin layer 4 is formed, for example, by blending the above-mentioned olefin-based resin with an ethylene-methyl methacrylate copolymer and melt-kneading the resin. The resin in the molten state is formed on the surface of the decorative layer 3 by extrusion coating. Laminate or
Alternatively, the decorative layer 3 is formed on the decorative layer 3 by a method such as dry lamination using an adhesive such as a two-component curable polyurethane or polyester resin, or heat lamination by fusing with a hot press. Laminated. The thickness of the olefin-based transparent resin layer 4 is 30 to 200.
It is preferably formed to about μm, more preferably 50 μm.
１００100 μm. When the olefin-based transparent resin layer 4 is used by laminating a sheet that has been previously formed into a sheet shape, the sheet may be any of a stretched sheet and an unstretched sheet, but has good formability such as V-cut processing. Therefore, an unstretched sheet is preferable.

In the present invention, as described above, the adhesion between the decorative layer 3 and the olefin-based transparent resin layer 4 is improved by blending the ethylene-methyl methacrylate copolymer into the olefin-based transparent resin layer 4. However, the blending of the ethylene / methyl methacrylate copolymer tends to cause a decrease in the inherent heat resistance of the olefin resin. Such a tendency is remarkable as the thickness of the olefin-based transparent resin layer 4 is required and the amount of the ethylene-methyl methacrylate copolymer is increased, and the amount of the expensive ethylene-methyl methacrylate copolymer is increased. Is disadvantageous in terms of cost.

For this reason, in the present invention, as shown in FIG. 2, the olefin resin layer 4 is composed of a layer (A layer) 4a containing an ethylene / methyl methacrylate copolymer and a layer (A layer) not containing the ethylene / methyl methacrylate copolymer. It is preferable that the ethylene-methyl methacrylate copolymer is blended in the above-described ratio only in the A layer 4a located on the decorative layer 3 side, with a two-layer structure including the B layer) 4b.

The effect of the present invention can be sufficiently obtained even if the A layer 4a is made thinner, as long as the ethylene / methyl methacrylate copolymer is present at least on the surface on the side of the decorative layer 3. Therefore, by making the A layer 4a as thin as possible to reduce the amount of the ethylene / methyl methacrylate copolymer used, it is possible to avoid the adverse effects caused by the blending of the ethylene / methyl methacrylate copolymer. A layer 4a
Is preferably 5 to 50 μm. If the thickness is less than 5 μm, it is not preferable in that the film formation becomes difficult and the effect of improving the adhesion is insufficient. If it exceeds 50 μm, the effect of reducing the amount of the ethylene / methyl methacrylate copolymer used cannot be sufficiently obtained, and it is not preferable from the viewpoint that the weather resistance is lowered.

As described above, the olefin-based transparent resin layer was
Having a layer structure is advantageous in terms of cost because the amount of expensive ethylene-methyl methacrylate copolymer can be reduced, and its technical significance is also important in securing the inherent heat resistance of olefin-based resins. The fact that the present invention is implemented in such an embodiment is particularly effective when the olefin-based transparent resin layer 4 requires a thickness.

In order to form the olefin transparent resin layer 4 into the two-layer structure as described above, for example, in the case of extrusion coating, (a) ethylene-methyl methacrylate copolymer is blended on the surface of the decorative layer 3. The olefin resin and (b) an olefin resin not blended with the ethylene / methyl methacrylate copolymer may be laminated by coextrusion so that (a) is on the decorative layer 3 side. Further, in the case of laminating a sheet formed in advance into a sheet shape by dry lamination, heat lamination, or the like, the sheet having the two-layer structure was formed by co-extrusion, and an ethylene-methyl methacrylate copolymer was blended. What is necessary is just to bond together so that the side may be the decoration layer 3 side.

In laminating the olefin-based transparent resin layer 4 on the decorative layer 3, an adhesive may be applied to the surface of the decorative layer 3.

As the adhesive, a two-component cured urethane resin,
Alternatively, a one-component moisture-curable urethane resin is preferable. These resins are selected from those similar to those used for the surface protective layer described later. The thickness of the adhesive layer is usually 10 to 30.
g / m ² . If a binder having the same composition as the above-mentioned adhesive is used as the binder of the ink for forming the decorative layer 3, application of the adhesive is not particularly necessary.

In the decorative sheet 1 of the present invention, although not particularly shown, the surface of the olefin-based transparent resin layer 4 is embossed.
An uneven pattern can be formed by hairline processing or the like.

As the embossing, the olefin-based transparent resin layer 4 is heated and softened, and is pressed and shaped with an embossing plate.
A known sheet-fed or rotary embossing machine is used for cooling and fixing. As the embossed uneven shape,
Wood channel grooves, stone plate surface irregularities (granite cleavage planes, etc.), fabric surface texture, pears, sand, hairlines, and alley grooves.

The concave portions of the concavo-convex pattern can be filled with a coloring ink or a paint (hereinafter simply referred to as a coloring ink) by a known wiping method (see Japanese Patent Publication No. 58-14312), if necessary.

The coloring inks include, for example, shellac,
Natural resins such as Koval, dammar, rosin, rosin ester or modified resins thereof, cellulose derivatives such as nitrocellulose, acetylcellulose, ethylcellulose, benzylcellulose, phenolic resins, urea resins, phthalic resins, maleic resins, melamine Resin, polyvinyl acetate resin, polyvinyl chloride resin, acrylic resin, polyvinyl alcohol, polyvinyl butyral,
Epoxy resins, silicone resins, polyester resins, polyamide resins, polyurethane resins or other synthetic resins, rubber derivatives such as chlorinated rubber, synthetic rubber, etc. are used as vehicle components, and colorants and sediments are settled in the vehicle. An ink obtained by adding an extender such as neutral barium sulfate, a plasticizer, or the like is used.

The coloring ink is coated on the concave portions of the sheet surface with a roll coat or a knife coat, and is then scraped off with a doctor blade or wiping paper to remove the colored ink coated on the convex portions of the sheet and color only the concave portions. The viscosity of the ink composition, the number of rotations of the roll, the blade angle of the doctor, the thickness, the sheet speed,
It is necessary to adjust the speed of the wiping paper, the hardness of the rubber roll, and the like. For example, the area of the colored ink is preferably the same as or similar to a conduit in the case of a grain pattern, and is preferably the same or similar to a crack in the case of a stone pattern.

On the surface of the olefin-based transparent resin layer 4, an organic ultraviolet absorber having a hydroxyl group in a molecule added to the olefin-based transparent resin layer 4 as described above is captured.
It is preferable to provide a surface protective layer 5 in order to prevent bleed-out, impart abrasion resistance and chemical resistance of the decorative sheet 1 and adjust the gloss of the surface.

The surface protective layer 5 can be expected to have a certain effect even with an epoxy resin, but is more preferably formed using a urethane resin having an isocyanate group. Examples of the urethane resin include a two-component curable urethane resin and a one-component moisture-curable urethane resin. The thickness of the surface protective layer is 0.5 to 100 μm, usually about 1 to 10 μm.

The two-component curable urethane resin is obtained by reacting a polyol as a main component and an isocyanate as a crosslinking agent (curing agent). The polyol has two or more hydroxyl groups in the molecule, and examples thereof include polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol.

As the isocyanate, a polyvalent isocyanate having two or more isocyanate groups in the molecule is used. For example, aromatic isocyanates such as 2,4-tolylene diisocyanate, xylylene diisocyanate, and 4,4'-diphenylmethane diisocyanate, or aliphatic (or alicyclic) such as hexamethylene diisocyanate, isophorone diisocyanate, and hydrogenated diphenylmethane diisocyanate. Isocyanates. Further, adducts or multimers of the above various isocyanates can also be used. For example, adducts of tolylene diisocyanate, trimers of tolylene diisocyanate and the like can be mentioned.

As a preferred embodiment in the case of a two-component curable urethane resin, the number (mol number) of isocyanate groups (—NCO) in the isocyanate is converted into the number (hydroxyl group) of the hydroxyl group (—OH group) of the polyol to be reacted therewith. Equivalent), even after the polyol and the isocyanate have reacted,
An embodiment in which a large number of unreacted isocyanate groups are surely left. In this case, -NCO group / -OH
The ratio of groups is at most about 1.4.

The surface protective resin layer 5 is made of a gravure coat,
Coating is performed by a method such as roll coating, knife coating, and air knife.

The use of the decorative sheet 1 of the present invention is as follows.
Interior decoration of buildings such as walls, ceilings and floors, surface decoration of fittings such as window frames, doors, handrails, surface decoration of furniture or cabinets of light electric / OA equipment, vehicle interiors such as automobiles and trains, aircraft interiors, window glass Makeup and the like.

When the decorative sheet 1 is used for interior and exterior of buildings, surface decoration of fittings and furniture, interior of vehicles, etc., it is more preferable to have the following functions (1) to (9). (1) Thermoformability comparable to polyvinyl chloride. In particular, it must have the characteristic that the change in elongation at constant load due to temperature changes is as slow and continuous as that of polyvinyl chloride.
In addition, deterioration of material mechanical properties such as strength reduction does not occur with heating or cooling. (2) Good creep resistance. Exterior and interior materials are often subjected to a constant load by fittings and furniture for long periods of time, and when creep deformation occurs, the loaded parts are turned up or peeled off. Therefore, it is preferable that the material does not cause creep deformation as much as possible. (3) Good cold bending strength. When bending such as V-cutting is performed in cold weather, if stress relaxation is insufficient, whitening, cracking, breakage, and the like are likely to occur in the bent portion. (4) Good organic solvent resistance. The decorative sheet can be prevented from swelling and deforming due to the solvent in the adhesive for bonding the decorative sheet and the adherend. The same applies when a decorative sheet having a multilayer structure is obtained. (5) High elongation at break and high impact strength. This is a characteristic for preventing a crack at a bent portion during V-cut processing. (6) Having an appropriate bending elastic modulus. The followability of the decorative sheet in the bending portion is sufficient. (7) Good transparency. (8) Whitening and turbidity due to recrystallization do not occur even when heating and cooling accompanying embossing or the like are applied. (9) Be superior in weather resistance. In particular, there is no loss due to bleed-out at the time of thermal processing of the organic ultraviolet absorber and at the time of outdoor exposure, and the added ultraviolet absorber functions sufficiently effectively.

In the present invention, the base sheet 2 is a sheet made of high-density polyethylene, a thermoplastic elastomer, a coloring agent, and an inorganic filler, and the olefin-based transparent resin layer 4 is made of a mixture of isotactic polypropylene and tactic polypropylene. By providing a colorless or colored transparent soft polypropylene-based resin as a main component, the various conditions required for the decorative sheet described above can be shared, and a highly practical decorative sheet can be obtained. .

[0086]

EXAMPLE 1 100 parts by weight of high-density polyethylene, 30% by weight of hydrogenated styrene-butadiene rubber, 15 parts by weight of calcium carbonate powder as an inorganic filler, and a mixture of titanium white, red stalk and graphite as a pigment Was added by 8 parts by weight and melt-extrusion-molded to form a film. The obtained base sheet 2 having a thickness of 100 μm was subjected to a corona discharge treatment on the surface of the base sheet 2, and then a urethane-based ink was obtained. [Urethane resin / acrylic resin = 5/5 (weight ratio) mixture as binder, pigment mainly consisting of red-penetrated pattern and carbon black. ), The gravure printing was performed to provide the wood-grained decorative layer 3, and then a urethane adhesive (two-component curing type composed of acrylic polyol and hexamethylene diisocyanate) was applied thereon.

Then, at an extruder at 240 ° C., an organic ultraviolet absorber having a hydroxyl group in the molecule was used as a 2─ (2′─).
A layer formed by extruding a random polypropylene (“Nobrene” manufactured by Sumitomo Chemical Co., Ltd.) containing 8000 ppm of hydroxy {3 ′, 5 ′} bis (α, α} dimethylbenzyl) phenylbenzotriazole and 4000 ppm of a hindered amine radical scavenger has a thickness of 70 μm. A layer formed by extruding a mixture obtained by melting and kneading 70% by weight of random polypropylene (“Noblen” manufactured by Sumitomo Chemical Co., Ltd.) and 30% by weight of an ethylene-methyl methacrylate copolymer (“Aclift WH303” manufactured by Sumitomo Chemical Co., Ltd.) has a layer thickness of 10 μm. Then, the resin in the molten state is co-extruded with a feed block method in a total thickness of 80 μm so that the layer containing the ethylene / methyl methacrylate copolymer becomes the decorative layer side on the adhesive-coated surface of the base material. And extrude it to form the irregular shape of the wood channel groove on the surface. Laminating was carried out while nipping between a cooling roll / embossing roll and a pressure roll to provide a transparent resin layer having a wood-grain conduit groove-like irregular pattern on the surface to obtain a decorative sheet.

Example 2 After performing corona discharge on the surface of the transparent resin layer of the decorative sheet obtained in Example 1, a two-part curable resin comprising 100 parts by weight of acrylic polyol and 8 parts by weight of hexamethylene diisocyanate was used. Was coated with a gravure roll coater to form a surface protective layer having a thickness of 3 μm, thereby obtaining a decorative sheet.

With respect to the decorative sheet obtained in the above example, the interlayer adhesion between the transparent resin layer and the decorative layer was measured by the following measuring method. Was also 3 kg / inch width. In addition, after performing a weather resistance test on the decorative sheets of Example 1 and Example 2 under the following conditions, the appearance and interlayer adhesion were evaluated. Regarding the appearance, the decorative sheet of Example 1 was whitened on the entire surface, but the decorative sheet of Example 2 was not whitened. Regarding interlayer adhesion, the decorative sheet of Example 1 had a width of 2.0 kg / inch, while the decorative sheet of Example 2 had a width of 0.4 kg / inch. An acceleration test for one week was conducted at a temperature of 70 ° C., but no shrinkage of the olefin-based transparent resin layer and no decrease in interlayer adhesion were observed. However, as for the decorative sheet of Example 1, whitening was observed on one surface due to the broad out of the ultraviolet absorber on the surface. On the other hand, the decorative sheet of Example 2 did not show such whitening.

[Measurement Method of Interlayer Adhesion] The transparent resin layer of the decorative sheet cut to a width of 1 inch and the substrate sheet were subjected to a tensile speed of 50 m in a 25 ° C. atmosphere using a tensile tester.
m / min, opening angle 180 between base sheet and transparent resin layer
And the peel strength was evaluated.

[Weather resistance test] A black arc temperature of 6 was measured using a carbon arc lamp type sunshine weather o-meter.
Exposure is performed for 1000 hours at 3 ° C. and a rain time of 18 minutes out of 120 minutes.

Comparative Example 1 A 100 μm thick sheet having the same composition as in Example 1 was used as a substrate without performing corona discharge treatment. The same urethane-based ink as that used in Example 1 was used on the surface of this substrate sheet. After performing gravure printing to provide a decorative layer similar to that of Example 1, a urethane-based adhesive similar to that of Example 1 was further applied thereon.

Next, a material obtained by melting 100% by weight of random polypropylene (“Noblen” manufactured by Sumitomo Chemical Co., Ltd.) at 240 ° C. from an extruder was extruded with a thickness of 80 μm onto the adhesive-coated surface of the base material. Similarly, laminating was performed while nipping between a cooling roll / embossing roll and a pressure roll to provide a transparent resin layer to obtain a decorative sheet.

The obtained decorative sheet was treated in the same manner as in the above example, and the interlayer adhesion between the transparent resin layer and the decorative layer was measured. The result was 2.1 kg / inch width.

[0095]

As described above, according to the decorative sheet of the present invention, the decorative layer and the olefin resin transparent resin layer can be formed by blending and using the ethylene / methyl methacrylate copolymer in the olefin transparent resin layer. The decorative sheet of the present invention is excellent in weather-resistant adhesion without any particular decrease in adhesion over time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one example of the decorative sheet of the present invention.

FIG. 2 is a longitudinal sectional view showing another example of the decorative sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Decorative sheet 2 Base sheet 3 Decorative layer 4 Olefin transparent resin layer 4a A layer 4b B layer 5 Surface protective layer

Continued on the front page F-term (reference) 4F100 AA08 AA21 AA30 AA37 AH02D AH07H AK05A AK07C AK07D AK25B AK51B AK51E AK71C AK73A AL03C AL03D AL05A AL05B AL05C AL06A AT00A BA03E02 H04E

Claims (3)

[Claims] 1. A decorative sheet in which a decorative layer and an olefin-based transparent resin layer are sequentially laminated on a base sheet, wherein the olefin-based transparent resin layer is mixed with an ethylene / methyl methacrylate copolymer. A decorative sheet, characterized in that: 2. A decorative sheet in which a decorative layer and an olefin-based transparent resin layer are sequentially laminated on a base sheet, wherein the olefin-based transparent resin layer has a two-layer structure, and A decorative sheet characterized in that an ethylene-methyl methacrylate copolymer is blended in a layer located on the side of the decorative layer. 3. The decorative sheet according to claim 1, wherein an organic ultraviolet absorbent having a hydroxyl group in a molecule is added to at least the outermost olefin transparent resin layer, and A decorative sheet comprising a resin layer and a surface protective layer formed of a resin having an isocyanate group in the molecule on the surface thereof.