JP2000190426A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently perform coloration, to sufficiently develop the effect of the addition of an inorg. filler and to prevent the generation of the surface flaw such as stripe irregularity or fish-eye at a time of film formation of a substrate sheet even in the case of the reduction of film thickness. SOLUTION: A polyolefin resin sheet, which is obtained by laminating an A-layer 2 comprising a colorless transparent resin compsn. composed of an olefinic thermoplastic elastomer wherein a soft segment of styrene/butadiene rubber or olefin rubber is mixed with a hard segment of crystalline polypropylene and not ontaining not only an inorg. filler but also a color pigment, and a B-layer 1 comprising a color resin compsn. prepared by further adding a color pigment to the resin compsn. of the A-layer 2 in the order of A-layer/B-layer/A-layer is used as a substrate sheet 10 and decoration treatment is applied to this substrate sheet 10 to constitute a decorative sheet. Coloration is sufficiently performed and the effect of the addition of an inorg. filler is sufficiently developed and the surface flaw such as stripe irregularity or fisheye at a time of film formation of the substrate sheet is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

Generally, as a decorative sheet as described above, a colored resin sheet to which a coloring pigment is added is used as a base sheet, and the decorative sheet is embossed with a concavo-convex pattern, printed with a pattern layer, or the like. The one with the configuration given was popular. As a material of the colored resin sheet used for these decorative sheets, a sheet using a polyvinyl chloride sheet (for example, see JP-B-28-5036 and JP-B-58-14314), and polyethylene, polypropylene and the like A sheet using a sheet of polyolefin resin (for example, Japanese Patent Application Laid-Open No. 54-62255)
Has been widely used.

[0003] Among them, the former decorative sheet using polyvinyl chloride has insufficient heat resistance, cannot be incinerated at the time of disposal (because hydrogen chloride gas is generated at the time of combustion), or has a plasticizer. There was a disadvantage that the surface was poor in stain resistance due to bleeding (leaching).

[0004] In the latter decorative sheet using a highly crystalline sheet composed of a polyolefin resin alone, the above-mentioned disadvantages peculiar to polyvinyl chloride can be improved, but there are the following disadvantages. . (1) Elongation concentrates locally at the time of molding, causing whitening and breakage (so-called "necking"). (2) The impact resistance is weak, and cracks and fractures occur during V-cut processing. (Especially, the crystallization progresses due to the heat history at the time of embossing from heating softening to embossing plate pressing to cooling, the sheet becomes brittle, and this tendency is strengthened.) (3) Since the degree of crystallization is high, the embossing conditions are high. But very narrow.

In order to improve some of the drawbacks, an olefin thermoplastic elastomer sheet made of a resin obtained by mixing a crystalline polyolefin resin as a hard segment and a rubber component (elastomer) as a soft segment is used. (See, for example, JP-A-6-79830, JP-A-6-210808, and JP-A-4-504384). However, these decorative sheets have the disadvantages (1) described above.
(3) can be solved, but when the added amount of the elastomer is increased, the tendency of another new defect such as a decrease in weather resistance and a decrease in heat resistance increases, and when these are improved, (1) to
The tendency of the disadvantage (3) is increased.

In order to color these olefin-based thermoplastic elastomers, a coloring pigment or an inorganic filler is further added. However, the flowability of the melt of the resin composition is reduced. When a resin composition (a melt thereof) is formed into a film by a method such as an extrusion method or a calendering method, streaky unevenness is generated in a sheet, surface smoothness is reduced, and furthermore, an There is a problem that the resin composition adhering to the T-die intermittently falls onto the sheet and adheres to the sheet to easily cause fisheye-like defects on the sheet. This tendency is caused by the fact that the sheet is particularly thinned (about 100 μm
Below), and the appearance of the decorative sheet was deteriorated.

[0007]

Means for Solving the Problems In order to solve the above problems, in the present invention, as a material of a base sheet,
Styrene in the hard segment of crystalline polypropylene
A resin composition comprising an olefin-based thermoplastic elastomer mixed with a soft segment of butadiene rubber or olefin rubber is employed, and as a layer constitution thereof, a colorless and transparent resin composition containing neither an inorganic filler nor a coloring pigment is used.
A polyolefin resin sheet obtained by laminating a layer and a layer B of a colored resin composition obtained by further adding a coloring pigment to the resin composition of the layer A, in the order of A layer / B layer / A layer;
This was subjected to a decorative treatment to obtain a decorative sheet. A configuration in which an inorganic extender is further added to the B layer may be adopted.

In addition, a transparent resin sheet selected from olefin thermoplastic elastomer, acrylic resin, ethylene / vinyl alcohol copolymer resin, and thermoplastic polyester resin is laminated on the surface of the decorative sheet. .

[0009] Among them, the transparent resin sheet on the outermost surface is made of an olefin-based thermoplastic elastomer,
In the transparent resin sheet on the outermost surface, an organic ultraviolet absorber having a hydroxyl group in the molecule is added, and an ultraviolet absorber bleed prevention layer comprising a resin layer having an isocyanate group in the molecule is added to the surface. I made it.

[0010] The decorative sheet of the present invention having the above-described structure maintains the weather resistance and heat resistance of the crystalline polypropylene, and causes the rubber component to cause necking and degraded impact resistance. And the disadvantages such as a narrow embossing condition width can be improved.

When a color pigment is added for coloring the olefin-based thermoplastic elastomer, or when an inorganic filler is further added for the purpose of improving dimensional stability, reducing costs, and imparting flame retardancy, the sheet is not treated with a pigment. Rather than adding uniformly at the same density in the thickness direction, the thickness direction is divided into three layers, and color pigments are added to the layers (A layer) on both the front and back sides of the sheet that directly touch the T-die, the calendar roller, etc. during film formation. And an inorganic filler were not added, and a coloring pigment or a coloring pigment and an inorganic filler were added only to the central layer (layer B). With such a configuration, the decorative sheet of the present invention can add a coloring pigment, or a coloring pigment and an inorganic filler, sufficiently exert the effect of the addition, and can prevent a decrease in film forming suitability due to the addition. Furthermore, in order to obtain sufficient weather resistance to the decorative sheet, not only an ultraviolet absorber is added to the A layer on the surface side, but also a ultraviolet absorber having a hydroxyl group in a molecule is selected.
In addition, a layer made of a resin having an isocyanate group in the molecule may be provided on the surface of the layer A on the surface side.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The olefin-based thermoplastic elastomer used in the layer A of the present invention comprises crystalline polypropylene as a hard segment and mixed with a soft segment made of styrene-butadiene rubber or olefin rubber.

The crystalline polypropylene used as a hard segment in the layer A of the present invention is preferably a propylene homopolymer (especially, one containing isotactic polypropylene as a main component, but also syndiotactic polypropylene or A mixture of isotactic polypropylene and syndiotactic polypropylene may be used.), A random copolymer or block copolymer of propylene / ethylene containing an ethylene component of 30% by weight or less, preferably 1 to 25% by weight, butene -Butene containing 20% by weight or less of -1
1 random copolymer or block copolymer. Among these, a copolymer of ethylene or butene-1 and propylene is particularly preferred from the application of the resin composition of the present invention such as a film or sheet. In addition, in order to improve the adhesiveness with another layer (B layer, decorative layer, etc.), an unsaturated carboxylic acid such as acrylic acid, fumaric acid, and itaconic acid, or Modification can also be performed by a method such as graft polymerization of the unsaturated carboxylic acid ester.

In particular, the A layer and the B layer, which are located on the outermost layer of the sheet, do not contain a color pigment absorbing light.
As for the layer, the resin composition constituting the layer is required to have practically sufficient weather resistance as a building interior material. Even if the interior material receives sunlight from a window or the like, a minimum of 1000 is usually measured using a sunshine weatherometer (carbon arc lamp type) weathering tester under the conditions of a black panel temperature of 63 ° C and a rainfall time of 18 minutes during 120 minutes. It is required that there is no appearance change such as discoloration, cracking, whitening, etc., and no delamination between layers upon exposure to time. To satisfy this requirement, it is preferable to add an ultraviolet absorber to the outermost surface of the decorative material. The additive is usually about 0.1 to 5% by weight. However, when the transparent resin sheet is laminated on the surface of the substrate sheet and an ultraviolet absorber is added to the transparent resin sheet, the ultraviolet absorber may not be added to the layer A on the surface side of the substrate sheet.

As the ultraviolet absorber, an inorganic ultraviolet absorber such as fine particle zinc oxide and fine particle cerium oxide, or an organic ultraviolet absorber is used. Organic materials are preferred from the viewpoint of transparency and dispersibility in resin. However, the organic type has poor compatibility with the polyolefin-based resin such as the layer A, and when the surface bleeds (spouts) over time (particularly at a high temperature), or when a process involving heating such as embossing is performed, When the sheet is cooled and recrystallized, there is a disadvantage that the ultraviolet absorber is separated and deposited and loses its effectiveness. In the present invention, in order to improve this, an organic ultraviolet absorber having a hydroxyl group in the molecule is selected,
It is preferable that an anti-bleed layer made of a resin having an isocyanate group in the molecule is provided on the surface of the layer A to which the ultraviolet absorber is added.

As an organic ultraviolet absorber having an OH group in the molecule, for example, 2- (2'-hydroxy-3 ',
5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t
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'-hydroxy-3 '
-Isobutyl-5'-propylphenyl) -5'-hydroxyphenyl-5 such as 5-chlorobenzotriazole
-Chlorobenzotriazole-based ultraviolet absorbers, 2-
2′-hydroxyphenylbenzotriazole-based ultraviolet absorption such as (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzotriazole and 2- (2′-hydroxy-5′-methylphenyl) benzotriazole 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'- such as 2,2 ', 4,4'-tetrahydroxybenzophenone Dihydroxybenzophenone ultraviolet absorbers, 2-hydroxy-4-
Use may be made of 2-hydroxybenzophenone UV absorbers such as methoxybenzophenone and 2,4-dihydroxybenzophenone, and salicylate UV absorbers such as phenyl salicylate and 4-t-butyl-phenyl-salicylate. In addition, a reactive ultraviolet absorber in which an acryloyl group or a methacryloyl group is introduced into a benzotriazole skeleton is also used.

Further, the deterioration of each layer due to ultraviolet rays is further prevented,
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)
Hindered amine radical scavengers and piperidyl radical scavengers such as sebacate and other compounds disclosed in, for example, Japanese Patent Publication No. 4-82625 are used. When a light stabilizer comprising a hindered amine radical scavenger is added to the layer (A) comprising a polyolefin, the layer (A) as well as the ink layer and the adhesive layer adjacent to the layer (A) may be added. If a resin containing no chlorine atom in the molecule, such as a polyurethane resin, a polyolefin resin, or a polyamide resin, is used for the layer, the weather resistance is improved. 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. To reactivate and inhibit the action of the scavenger,
The weather resistance is not sufficiently improved.

In the layer A, styrene-butadiene rubber or olefin rubber is used as a soft segment added to crystalline polypropylene. As the styrene-butadiene rubber, more preferably, a hydrogenated styrene-butadiene rubber is used. This is one in which the unsaturated bond of the styrene-butadiene rubber is saturated by the addition of hydrogen, and more excellent weather resistance is obtained. As the olefin rubber, ethylene-propylene copolymer rubber (EP
M), ethylene-propylene-non-conjugated diene copolymer rubber (EPDM), or those obtained by further copolymerizing an α-monoolefin such as butene-1, pentene-1, hexene-1 and the like. The copolymerization ratio of ethylene and propylene is about 20:80 to 80:20 (weight ratio).
In addition, atactic polypropylene can also be used as the olefin rubber. The mixing ratio of the hard segment of crystalline polypropylene and the soft segment made of styrene-butadiene rubber or olefin rubber is hard segment / soft segment = 95/5 to 60/40 (weight ratio). When the mixing ratio is within the above range, the effect of forming a thermoplastic elastomer as described above can be sufficiently obtained.

As the resin composition for forming the layer B, a resin composition obtained by adding a coloring pigment to the composition of the olefin-based thermoplastic elastomer used for the layer A is used. Color pigments added to the B layer include inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine, cobalt blue, titanium yellow, graphite, carbon black, isoindolinone, Hansa Yellow A, quinacridone, Permanent red 4R,
Pearlescent luster (pearl) consisting of organic pigments (or dyes) such as phthalocyanine blue, Indaslenbri RS, and aniline black, metal pigments such as aluminum and brass, titanium dioxide-coated mica, and foil powder such as basic lead carbonate
Pigments and the like can be used. These are added and dispersed as powder or flaky foil pieces. Coloring by adding a pigment may be either transparent coloring or opaque (concealing) coloring. The amount of the coloring pigment to be added varies depending on the type of the pigment, the desired color tone and the concealing property, but is usually at most about 30% by weight. Further, an inorganic filler is added to impart dimensional stability and flame retardancy to the base sheet and to reduce material costs. As the inorganic filler, a powder having a particle size of about 0.1 to 10 μm, such as silica, magnesium hydroxide, clay, calcium carbonate, barium sulfate, and aluminum hydroxide, is usually added at about 5 to 30% by weight.

The base sheet in the decorative sheet of the present invention is constituted by alternately laminating the above-mentioned A layers and B layers in the order of A layer / B layer / A layer. The thickness of each layer constituting the base sheet is not particularly limited and can be arbitrarily selected. From the viewpoint of the coloring effect on the base sheet and the effect of improving film forming suitability, the ratio of the thickness of each layer is as follows: A layer (front side) / B layer = 1/9 to 5/5, B layer / A layer (back side) ) = 9/1 ~
About 5/5, and layer A (front side) / layer A (back side) =
It should be about 1/1. For building materials and interior decorative sheets, usually the thickness (total thickness) of three layers of the base sheet is 25 to 3
00 μm. The method of forming the base sheet by laminating each of the layer A (front side), the layer B, and the layer A (back side) is not particularly limited. For example, a hot press method, a coextrusion lamination method from a T-die, a dry lamination method, or the like can be used.

The base sheet used in the present invention has a correlation between the dimensional shrinkage upon heating and the crack resistance and rupture resistance during bending such as V-cut processing, and after heating in a 100 ° C. atmosphere for 30 minutes. In the case of a long strip-shaped sheet, the dimensional shrinkage ratio (based on before heating) is preferably in the range of -2 to + 7% in the sheet longitudinal direction and -7 to + 2% in the sheet width direction.
If the dimensional shrinkage ratio deviates from this range, cracks are likely to occur during V-cut processing, which is not preferable. The reason why the allowable value of the heating dimensional shrinkage rate is different in the sheet longitudinal direction and the width direction is that the history of the material dynamics of the sheet at the time of sheet production, and how the impact force at the time of sheet processing is applied is different from the longitudinal direction. This is because it differs in the width direction. This dimensional shrinkage upon heating has a large correlation mainly with the stretching of the base material sheet. If the film is not stretched, the above-mentioned heating dimensional shrinkage falls within this range, and if it is stretched three times or more, the heating dimensional shrinkage generally falls outside this range. Therefore, in the case of stretching, the stretching ratio is controlled so that the heating dimensional shrinkage ratio falls within the above range.

Although it is possible to print a pattern or apply an adhesive directly on the substrate sheet itself, it is necessary to make the adhesive strength between the ink or adhesive and the substrate sheet stronger. Applies an easy-adhesion layer such as a coating of an easy-adhesion layer, a corona discharge treatment, a plasma treatment, and an ozone spraying treatment on the front surface, the back surface, or both the front and back surfaces of the substrate sheet. A urethane resin, a chlorinated polypropylene, or a chlorinated polyethylene is used as the easy-adhesion layer (also referred to as a primer layer or an anchor layer), and a urethane resin is particularly preferable. The easy-adhesion layer may be provided, for example, between the base sheet and the pattern layer or on the adherend side of the decorative sheet.
An easy adhesion layer may be provided at a position other than the example.

As the urethane resin (polyurethane),
There are two-component curable urethane resins and one-component curable urethane resins. Among them, the two-component curable urethane resin is a urethane resin having a polyol (polyhydric alcohol) as a main component and an isocyanate as a crosslinking agent (curing agent). As the polyol, those having two or more hydroxyl groups in the molecule, for example, polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, polycarbonate polyol,
A polyurethane polyol or the like is used. As the isocyanate, a polyvalent isocyanate having two or more isocyanate groups in a molecule is used. For example,
Aromatic isocyanates such as 2-4 tolylene diisocyanate, xylene diisocyanate, 4-4 diphenylmethane diisocyanate, or aliphatic or fatty acids such as 1,6-hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate Cyclic isocyanates are used. Alternatively, adducts or multimers of these isocyanates may be used.

The one-component curable urethane resin is a composition containing a prepolymer having an isocyanate group at a molecular terminal as an essential component. The prepolymer is usually a polyisocyanate prepolymer having one or more isocyanate groups at both molecular terminals, and is a solid thermoplastic resin at room temperature. The isocyanate groups react with each other due to moisture in the air, and as a result, a reactant having a urea bond in the molecular chain is generated, and the isocyanate group at the molecular terminal further reacts with the urea bond to cause a biuret bond. Branches and causes a crosslinking reaction. Although the skeleton structure of the molecular chain of the prepolymer having an isocyanate group at the molecular terminal is arbitrary, specific examples include a polyurethane skeleton having a urethane bond, a polyester skeleton having an ester bond, and a polybutazine skeleton. One or two of these as appropriate
Adopt more than one kind of skeleton structure. If there is a urethane bond in the molecular chain, this urethane bond also reacts with the terminal isocyanate group to generate an allophanate bond,
This allophanate bond also causes a crosslinking reaction.

In order to make the adhesion treatment of the base sheet more reliable, first, the base sheet itself is modified by graft polymerization of unsaturated carboxylic acid as described above, or the surface of the base sheet is subjected to corona discharge treatment. , A polar functional group having an active hydrogen atom such as a carboxyl group or a hydroxyl group is imparted to the surface of the base material sheet by one of an ozone spraying treatment and a plasma treatment, and then a one-component curing type or It is preferable to form an easy-adhesion layer of a two-component curable urethane resin. In this case, urethane bonds are also generated between the polar functional groups on the surface of the base sheet and the isocyanate groups in the easy-adhesion layer, and the base sheet and the easy-adhesion layer are firmly adhered to each other.

The ultraviolet absorbent bleed prevention layer is formed from a resin layer having an isocyanate group in the molecule. The thickness of this layer is about 0.1 to 100 μm, usually 1 to 10 μm
It is about. A typical example of a resin having an isocyanate group in a molecule is a urethane resin. As the urethane resin, the above-mentioned resins can be used, but it is preferable to mix an isocyanate excessively when reacting the polyol with the isocyanate so that the unreacted isocyanate group remains after curing.

The decoration treatment applied to the base sheet includes:
There are (1) printing of a pattern layer, (2) formation of a metal thin film, (3) embossing (heating press), shaping of an uneven pattern by hairline processing, and the like. FIG. 1 shows a decorative sheet produced by performing these decorative treatments.

The decorative sheet S shown in FIG. 1A is composed of the base sheet 10 itself, and the coloring of the B layer 1 with a coloring pigment corresponds to a decoration process. Specifically, a layer A 2 of a resin composition of an olefin-based thermoplastic elastomer without pigment was laminated on both sides of a layer B 1 in which a coloring pigment G was added to the resin composition of an olefin-based thermoplastic elastomer as described above. Things.

The decorative sheet S shown in FIG. 1 (b) has a pigment-free olefinic heat on both sides of a B layer 1 in which a coloring pigment G and an inorganic filler F are added to the resin composition of the olefinic thermoplastic elastomer. A base sheet 10 is prepared by laminating an A layer 2 of a resin composition of a plastic elastomer, an easy-adhesion layer 3 is formed on the base sheet 10, and a pattern layer 4 is formed thereon by printing. . The pattern layer is printed by a known printing method such as gravure printing, offset printing, silk screen printing, transfer printing from a transfer sheet, and the like, and the pattern is formed with ink (or paint). Examples of the pattern include a wood pattern, a stone pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, and a solid surface. If the pattern is transparent coloring of the base sheet,
It may be provided on the front surface, the back surface, or both the front and back surfaces of the base sheet. When the base sheet is opaque, the ink (or paint) provided only on the surface of the base sheet may be a chlorinated polyolefin such as chlorinated polyethylene or chlorinated polypropylene, a polyester resin, a urethane resin, or an acrylic resin as a binder. , Vinyl acetate resin,
Vinyl chloride / vinyl acetate copolymer, cellulosic resin,
And the like, or a mixture of two or more thereof, to which known pigments as listed above are added. When printing directly on the base sheet, a chlorinated polyolefin, a two-component curable urethane resin or the like is preferable as a binder in terms of adhesiveness, but if an easy-adhesion primer is appropriately selected and a layer is formed, other binders may be used. Even when used, sufficient adhesiveness can be obtained.

The decorative sheet S shown in FIG. 1 (c) is one in which a concave and convex pattern composed of the concave portions 5 is formed on the base sheet 10 by embossing (heating press), hairline processing or the like. The embossing is performed by heating and softening the laminated polyolefin resin sheet, pressurizing and shaping the sheet with an embossing plate, cooling and fixing to form an uneven pattern, and is performed using a known single-sheet or rotary embossing machine. be able to. Examples of the uneven shape include a wood grain board conduit groove, a stone board surface unevenness (granite cleavage face, etc.), a joint groove for tiled or brickwork, a cloth surface texture, a satin finish, a grain, a hairline, a linear groove, and the like.

Further, if necessary, as shown in FIG.
The colored ink 6 may be filled into the concave portion 5 having the concave and convex pattern by a known wiping method (for example, see Japanese Patent Publication No. 58-14312). The same coloring ink as described above can be used. However, in terms of wear resistance,
It is preferable to use a two-component curable urethane resin as the binder.

As a decoration process, a metal thin film may be provided on the base sheet. The metal thin film is formed using a metal such as aluminum, chromium, gold, silver, and copper by a method such as vacuum evaporation and sputtering. Alternatively, a combination of these may be used. The metal thin film may be provided on the entire surface or partially in a pattern.

The decorative sheet S shown in FIG. 1 and FIG.
The base sheet 10 made of a laminate of layer / layer B / layer A has been subjected to a decoration treatment.
Is obtained by laminating a transparent resin sheet 20 as a top sheet on a base sheet 10 made of this laminate.

The decorative sheet S shown in FIG. 3A has a transparent resin sheet 20 on the base sheet 10 with an adhesive layer 7 interposed therebetween.
And a pattern layer 4 is formed on the transparent resin sheet 20 by printing. The decorative sheet S shown in FIG. 3B has a pattern layer 4 formed by printing on the surface of the base sheet 10.
Is formed, and a transparent resin sheet 20 is laminated thereon by heat fusion. The decorative sheet S shown in FIG. 3 (c) is composed mainly of a resin composition of an olefin-based thermoplastic elastomer colored by adding a pigment G and an inorganic filler F.
The pattern layer 4 is formed by printing on the surface of the base sheet 10 to be a layer, and the transparent resin sheet 20 is laminated thereon via the adhesive layer 7, and then the concavo-convex pattern composed of the concave portions 5 is formed by embossing. Things. And the base sheet 1
No. 0 is provided with an easy-adhesion layer 8 on the adherend side.

Here, as the resin forming the transparent resin sheet, a resin selected from acrylic resin, ethylene / vinyl alcohol copolymer resin, thermoplastic polyester resin, and olefin-based thermoplastic elastomer is used. .

Examples of the acrylic resin include poly (methyl) methacrylate, poly (meth) ethyl acrylate, poly (meth) acrylate, butyl poly (meth) acrylate, and methyl (meth) acrylate / (meth) acrylate. Such as butyl acrylate copolymer, ethyl (meth) acrylate / butyl (meth) acrylate, ethylene / methyl (meth) acrylate, and styrene / methyl (meth) acrylate Acrylic resin consisting of a homo- or copolymer containing (meth) acrylic acid ester. The thickness of this acrylic resin sheet is 20-100μ
m.

The ethylene / vinyl alcohol copolymer resin layer is formed by laminating by hot melting or by using an adhesive such as a two-component curable urethane resin or a melt-extruded (extrusion) coated polyethylene. It is formed by laminating a film on a resin layer serving as a substrate, and has a thickness of 10 to 100 μm.
And more preferably 12 to 25 μm. As the film, a film obtained by molding a random copolymer of ethylene and vinyl alcohol into a film is generally used. The ethylene-vinyl alcohol copolymer resin film may be a stretched film or an unstretched film, but it is preferable to use an unstretched film in terms of film flexibility, bending workability, embossability, and the like. preferable. Ethylene-vinyl alcohol copolymer films have different thermoplastic copolymers and water resistance, and the rigidity, oil resistance, solvent resistance, and chargeability of vinyl alcohol. Can be arbitrarily adjusted, but the ethylene component is preferably 30 to 45 mol% in order to obtain a film having both characteristics as much as possible and having excellent workability. If it is less than 30 mol%, the thermoplasticity, heat processing suitability, and water resistance are poor, and if it exceeds 45%, the rigidity, oil resistance, solvent resistance, and antistatic property are poor, which is not preferable.

The thermoplastic polyester resin is represented by polyethylene terephthalate, polybutylene terephthalate, ethylene terephthalate / isophthalate copolymer and the like, and aromatic components such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid as acid components. It is a copolymer obtained as an ester of an aliphatic dicarboxylic acid and an aliphatic diol such as ethylene glycol, diethylene glycol, butanediol, or hexanediol as an alcohol component. Although any of stretched and unstretched sheets can be used, unstretched sheets are preferable from the viewpoint of suitability for embossing and forming such as V-cutting.

Examples of the olefin-based thermoplastic elastomer include those similar to the layer A of the base sheet,
No. 3278, comprising a hard segment of isotactic polypropylene and a soft segment of atactic polypropylene;
And terpolymers of ethylene-propylene-butene described in JP-A-7-316358 and those obtained by adding a soft segment of hydrogenated styrene-butadiene rubber to high-density polyethylene.
The thickness is usually about 50 to 100 μm.

As the filler, calcium carbonate,
Average particle size of barium sulfate, clay, talc, etc. 0.1-1
A powder of about 0 μm is used, and these are added in an appropriate amount as needed.

As the flame retardant, powders such as aluminum hydroxide and magnesium hydroxide are used, and these are added when it is necessary to impart flame retardancy. The addition amount is about 10 to 150 parts by weight based on 100 parts by weight of the polyolefin resin.

As a method of laminating a transparent resin sheet selected from an acrylic resin, an ethylene / vinyl alcohol copolymer resin, a thermoplastic polyester resin, or an olefin-based thermoplastic elastomer on the surface of a base sheet, there are two methods. Using or not using an adhesive such as a liquid-curable urethane resin, melt-extrusion coating (extrusion coating), fusing by hot pressing, or using an adhesive such as a two-liquid-curable urethane resin or polyester resin There are dry lamination etc.

The decorative sheet of the present invention has a single-layer structure in which a decorative treatment is merely applied to a base sheet (FIGS. 1 and 2) and a laminate sheet in which a transparent resin sheet is laminated on the base sheet (FIG. 3). Either form can be adopted.

The decorative sheet of the present invention can be laminated on another adherend (backing material). The adherend is the final product, and a decorative sheet may be laminated to make up the surface, or if necessary, may be applied to the back of the decorative sheet to reinforce the mechanical strength of the decorative sheet or to provide concealment. In some cases, bodies are stacked. When laminating on the adherend, the adhesive layer may be omitted if the decorative sheet itself can be adhered to the adherend (at a thermal melting point or the like). If the decorative sheet itself does not adhere to the adherend, an appropriate adhesive is used.

The object to be adhered is a plate material of various materials, a plate material such as a curved surface plate, a three-dimensional article, an article of various shapes such as a sheet (or film). Board materials, three-dimensional shaped articles,
Materials used for any of the sheets (films) include wood veneer, wood plywood, particle board, wood board such as wood fiber board such as medium density fiber board (MDF), metal such as iron and aluminum, and acrylic resin. , Polycarbonate,
There are resins such as ethylene-vinyl acetate copolymer, ethylene vinyl acetate, polyester resin, polystyrene, polyolefin resin, ABS, phenol resin, polyvinyl chloride, cellulose resin, and rubber. Materials used exclusively as plate materials or three-dimensionally shaped articles include glass,
There are ceramics such as porcelain, cement such as ALC (foamed lightweight concrete), non-cement ceramic materials such as calcium silicate and gypsum. Exclusively sheet (or film)
As materials used as paper, high-quality paper, paper such as Japanese paper,
There is a nonwoven fabric or woven fabric made of fibers such as carbon, asbestos, potassium titanate, glass, and synthetic resin.

As a method of laminating the decorative sheet on these various adherends, for example, (1) a method of laminating by pressing a plate-like substrate with a pressure roller via an adhesive layer, and (2) JP-B-50-19132, JP-B-43-27488
As described in Japanese Unexamined Patent Publication, a decorative sheet is inserted between the male and female molds for injection molding, the molds are closed, the molten resin is injected and filled from the male mold gate, and then cooled to form a resin molded product. So-called simultaneous injection molding laminating method in which a decorative sheet is adhered and laminated on the surface at the same time as the molding of (3) JP-B-56-457.
No. 68, Japanese Patent Publication No. 60-58014, etc., a decorative sheet is opposed to or placed on the surface of a molded article with an adhesive layer interposed therebetween, and the decorative sheet is drawn by vacuum suction from the molded article side. Laminating a decorative sheet on the surface of the molded product by pressure difference,
As described in the so-called vacuum press laminating method, (4) JP-B-61-5895, JP-B-3-2666, etc., an adhesive layer is formed in the longitudinal direction of a columnar substrate such as a column or a polygonal column. A so-called lapping method in which the decorative sheets are successively pressed and laminated on a plurality of side surfaces constituting the columnar body by a plurality of rollers having different directions while supplying the decorative sheets therebetween. ) As described in Japanese Utility Model Publication No. 15-31122, JP-A-48-47972, etc., a decorative sheet is first laminated on a plate-like substrate via an adhesive layer, and then the plate-like substrate is On the surface on the side opposite to the decorative sheet, the cross section reaching the interface between the decorative sheet and the plate-like base material is V-shaped or U-shaped.
There is a so-called V-cut or U-cut processing method in which a letter-shaped groove is cut, an adhesive is applied to the groove, and the groove is bent to form a box or a column.

In particular, as the method of bonding the decorative sheet of the present invention to a three-dimensional object having irregularities, of the above methods, the simultaneous lamination method of injection molding, the vacuum press laminating method, the lapping method, the V-cut method, and the like are preferable.

The decorative sheet of the present invention is used for various applications after being laminated on various adherends and subjected to a predetermined molding process. For example, interiors of buildings such as walls, ceilings, floors, doors, door frames,
Window frames, skirting boards, handrails and other surface fittings for furniture, furniture such as chests,
Surface makeup for cabinets of light electric / OA equipment, automobiles,
Vehicle interiors such as trains, aircraft interiors, window glass makeup, etc.

[0049]

(Example 1) As a resin composition constituting the layer A, [A1] a soft segment composed of atactic polypropylene (having a number average molecular weight Mn of 6,500 and a boiling n-heptane insoluble matter of 5% by weight); A2] Density 0.9
0 g / cm ³ , melt flow rate (MFR) (230
° C) = 1.0 g / 10 min. Of crystalline isotactic polypropylene, and these were set to have a weight composition ratio of A1 / A2 = 25/75.

The same composition as that used for the resin composition constituting the layer A is used for the layer B, and titanium white, red iron oxide, graphite and carbon black are mainly used for 100 parts by weight of the same composition. What added the coloring pigment 8 weight part and the inorganic filler which consists of calcium carbonate powder 10 weight part was used.

The composition obtained by heating and melting the composition of the layer A and the composition of the layer B obtained as described above was added to the layer A / layer B / A
It is melt co-extruded from a T-die in a three-layer structure, cooled and solidified on a cooling drum, and is a laminated sheet of an unstretched olefin-based thermoplastic elastomer (total thickness: 80 μm, thickness ratio: A layer / B layer / A Layer = 10/1060/10), and this was used as a substrate sheet. The front and back surfaces of the obtained brown opaque colored base sheet are subjected to corona discharge treatment to give a surface wetting index of 38 dyn / cm, and the main agent is 100 parts by weight of acrylic polyol and the curing agent is 1,6-hexa on the surface. A two-part curable urethane resin composition consisting of 8 parts by weight of methylene diisocyanate is applied by gravure roll coating over the entire surface to a dry thickness of 3 μm to form a primer layer. vinyl·
Gravure printing of a grain pattern was performed using an ink obtained by adding a red pigment and a coloring pigment mainly composed of carbon black to a vinyl acetate copolymer = 1/1 weight ratio mixture. Further, a two-part curable urethane resin composition (trade name “DT-5” manufactured by Dainippon Ink and Chemicals, Inc.) is applied thereon with a gravure roll coat at a dry film thickness of 3 μm to form a heat seal layer. Was formed.

On the other hand, a benzotriazole-based ultraviolet absorber having a hydroxyl group in a molecule (trade name “LA62”, manufactured by Asahi Denka Kogyo KK) was added in the same composition as the layer A in an amount of 0.8.
% Of a hindered amine radical scavenger, and 0.05% by weight of erucamide as a lubricant. A two-component curable polyurethane composition (Dai Nippon Ink Co., Ltd.) Chemical Industry Co., Ltd.
Co., Ltd., trade name “DT-5”) is applied with a gravure roll coat at a dry film thickness of 3 μm to form a heat seal layer,
This was used as a transparent resin sheet (expression sheet).

Then, the transparent resin sheet, which is a surface sheet, and the opaque colored base sheet are overlapped so that the heat seal layers face each other, and the two sheets are thermally fused by a rotary hot press embossing machine. Simultaneously with the attachment, a wood grain conduit groove was embossed on the surface of the transparent resin sheet. The heating temperature of the sheet is 150 ° C and the pressing pressure of the embossing plate is 25 kg / c.
m ² , the sheet feed speed was 15 m / min, and the plate surface temperature was 40 ° C.

Next, after applying a corona treatment (3 kw, speed 50 m / min) to both the front and back surfaces of the laminated sheet, a colored ink containing a brown pigment only in the concave portions of the uneven pattern (two-component curable urethane resin was used as a binder). , A pigment mainly composed of carbon black was added) by a doctor blade method. Then, on the entire surface wiped,
A composition formed by adding silica fine particles to a two-part curable polyurethane obtained by mixing 12 parts by weight of 1,6-hexamethylene diisocyanate with 100 parts by weight of an acrylic polyol is gravure coated to form an ultraviolet absorbent bleed prevention layer, A resin composition obtained by mixing a vinyl chloride-vinyl acetate-maleic acid copolymer and 2,4-tolylene diisocyanate was gravure-coated to a thickness of 2 μm on the back surface of the laminated sheet to form a back surface primer layer. Thereby, a desired decorative sheet was obtained.

Example 2 A base sheet similar to that in Example 1 was subjected to corona discharge treatment to prepare a sheet provided with a primer layer and a pattern layer. On top of this, 10 g of a two-part curable urethane resin adhesive containing 1,6-hexamethylene diisocyanate as a curing agent and an acrylic polyol as a main component.
/ M ² (when dry) was applied to dry the diluent solvent. Further, a transparent acrylic resin sheet made of poly (methyl methacrylate) having a thickness of 50 μm to which a 2% by weight of a benzotriazole-based ultraviolet absorber having a hydroxyl group in a molecule is added as a surface sheet is pressed thereon, and pressed. After curing for 4 days in an atmosphere of 40 ° C., the printing ink and the adhesive were cross-linked and cured to prepare a decorative sheet.

Example 3 An unstretched sheet made of a 50 μm-thick transparent ethylene / vinyl alcohol copolymer to which 2% by weight of a benzotriazole-based ultraviolet absorber having a hydroxyl group in a molecule was added as a surface sheet was used. A decorative sheet was prepared in the same manner as in Example 2 except for the presence of the sheet.

Example 4 As a surface sheet, an unstretched sheet made of a transparent ethylene terephthalate / isophthalate copolymer having a thickness of 50 μm to which 2% by weight of a benzotriazole-based ultraviolet absorber having a hydroxyl group in a molecule was added. A decorative sheet was produced in the same manner as in Example 2 except that the above-mentioned was used.

Comparative Example 1 The same polyolefin resin sheet as in Example 1 except that the resin composition constituting the layers A and B of the substrate sheet and the transparent resin sheet consisted of only crystalline isotactic polypropylene. Was used. All others were the same as in Example 1.

(Comparative Example 2) A single-layer sheet having a thickness of 80 µm and comprising only the layer B as the base sheet was used. Others were the same as Example 1.

(Comparative Example 3) For both the base sheet and the transparent resin sheet, a single-layer sheet having a thickness of 80 μm and made of biaxially oriented polyethylene having a stretching ratio of 5 without a rubber-based substance (soft segment) was added as a resin composition. Using. Others were the same as Example 1.

Comparative Example 4 The same procedure as in Example 1 was carried out except that the surface of the colorless transparent sheet was not provided with an ultraviolet absorbent bleed prevention layer.

[Performance Evaluation Test] Tables 1 and 2 show the results of comparing the decorative sheets of Examples 1 to 4 and the decorative sheets of Comparative Examples 1 to 4 in various physical properties.

[Test Method] Transparency Visually, the clearness of the pattern seen through the colorless transparent surface sheet and the presence or absence of white turbidity were evaluated. 2. Weather resistance 10 with carbon arc light type sunshine weatherometer
Irradiate for 00 hours and observe appearance changes such as cracks, whitening and discoloration (visual judgment). If the change in appearance becomes remarkable in less than 1000 hours (visual judgment), the operation is stopped at that point. Irradiation was performed under the condition that the black panel temperature was 63 ° C. and the rainfall time during 120 minutes was 18 minutes. 3. Heat resistance Heat in an 80 ° C. atmosphere for 3 minutes, and visually check the discolored state before and after that and whitening due to bleed of the ultraviolet absorber. 4. Sheet breakage / crack during V-cut Using a glue of ethylene-vinyl acetate copolymer emulsion, glue the base sheet side of the decorative sheet to lauan plywood with a thickness of 10 mm, and then laminate the sheet. On the opposite side to the section V reaching the interface between the plywood and the adhesive layer
The groove is cut in the shape of a letter, an adhesive of an ethylene / vinyl acetate copolymer emulsion is applied to the groove, and then the plywood is bent so that the groove is closed to form an L-shaped plywood (cross section). ). The ambient temperature during processing was 10 ° C. 5. Reproduction of uneven pattern Evaluation was made visually. 6. Adhesive force A sample obtained by cutting out a laminate of a decorative sheet / base sheet or a surface sheet / decorative sheet to a width of 1 cm was pulled in a direction perpendicular to the width direction at a pulling speed of 50 mm / min and an ambient temperature of 2.
At 0 ° C., a tensile test was performed such that the tensile directions of both samples were 180 ° with each other, and the tension at the time of peeling of the interlayer interface was measured. 7. Heating dimensional shrinkage ratio The decorative sheet is heated in an atmosphere of 100 ° C. for 30 minutes, and is obtained by [(dimension after heating) − (dimension before heating)] × 100 /
(Dimensions before heating) = Heat dimensional shrinkage (%) was determined for each of the longitudinal direction (MD) and the width direction (TD). 8. Suitability for film formation of sheet (1) The presence or absence of defects such as fish eyes and streaks on the surface of the sheet itself was visually evaluated. (2) The presence or absence of missing (non-inlaid portion) of the printed pattern was visually evaluated.

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

As described above, the decorative sheet of the present invention has a resin composition of a colored base sheet, in which a soft segment made of styrene-butadiene rubber or olefin rubber is added to a hard segment of crystalline polypropylene. The above-mentioned drawbacks (1) to (3) found in a decorative sheet using a highly crystalline sheet made of a conventional polyolefin resin alone can be improved. In addition, the colored base sheet is made up of a three-layer laminate, and the outermost surface layer on the front and back surfaces does not contain any coloring agent or inorganic filler, and only the intermediate layer contains coloring pigment and inorganic filler. As a result, the coloring is sufficiently performed, the effect of the addition of the inorganic filler is sufficiently exhibited, and even when the base sheet is made thin, surface defects such as stripe unevenness and fish eyes at the time of forming the base sheet are not generated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a decorative sheet according to the present invention.

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

FIG. 3 is a sectional view showing another example of the decorative sheet according to the present invention.

[Explanation of symbols]

 S decorative sheet 1 B layer 2 A layer 3 Easy adhesion layer 4 Pattern layer 5 Depression 6 Colored ink 7 Adhesive layer 8 Easy adhesion layer 10 Base sheet 20 Transparent resin sheet

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) C08L 9/06 C08L 9/06 23/10 23/10 F term (reference) 4F100 AA00B AK03A AK03B AK03C AK03D AK07A AK07B AK07C AK25D AK41D AK51E AK69D AK73A AK73B AK73C AL05A AL05B AL05C AL09A AL09B AL09C AL09D AN02A AN02B AN02C BA03 BA04 BA05 BA06 BA10A BA10C BA10D BA10E BA16 CA07D CA13B GB08 GB33 JA11A JA11B JA11C JB16A JB16B JB16C JB16D JN01A JN01C JN01D 4J002 AC08X BB12W BB14W BB15W BP02W DA036 DA096 DC006 DE096 DE106 DE116 DE136 DE156 DE286 DJ006 FD096 FD097 GL01 GN00

Claims (4)

[Claims] 1. A base sheet made of an olefin-based thermoplastic elastomer in which a hard segment of crystalline polypropylene is mixed with a soft segment of styrene-butadiene rubber or olefin rubber, and is a colorless and transparent material containing neither an inorganic filler nor a coloring pigment. Polyolefin comprising three layers of A layer composed of a resin composition and B layer composed of a colored resin composition obtained by further adding a coloring pigment to the resin composition of the A layer, in the order of A layer / B layer / A layer A decorative sheet using a resin sheet, which is subjected to a decoration process. 2. The decorative sheet according to claim 1, wherein an inorganic extender is further added to the B layer. 3. The surface of the decorative sheet according to claim 1 or 2, wherein an olefin-based thermoplastic elastomer, an acrylic resin, an ethylene / vinyl alcohol copolymer resin,
A decorative sheet obtained by laminating transparent resin sheets selected from any of thermoplastic polyester resins. 4. The decorative sheet according to claim 3, wherein:
The uppermost transparent resin sheet is made of an olefin-based thermoplastic elastomer, and an organic ultraviolet absorber having a hydroxyl group in a molecule is added to the outermost transparent resin sheet, and an isocyanate group is added to the surface of the transparent resin sheet. A decorative sheet having an ultraviolet absorbent bleed prevention layer comprising a resin layer.