JP2001030455A - Decorative sheet and decorative material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make bending process suitability better, to avoid whitening and generation of cracks and to improve emboss process suitability even for a non-vinyl chloride decorative sheet. SOLUTION: In a decorative sheet wherein a polyolefin resin sheet is decorative-treated, on a stress-strain curve obtd. by a tensile loading test of the decorative sheet, the slope G of the stress-strain curve at the middle point stress Ym as the middle point between the yield point stress Yy and the inflection point stress Yi at a point where the stress decreases with increase in strain from the yield point stress Yy and then, it starts to increase, is set at least -0.2N/mm2.%. As the decorative treatment, there exists shaping of an uneven pattern based on heat embossing, etc. A decorative material has a constitution wherein this decorative sheet is laminated on a base material.

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 exterior decoration, interior decoration, fittings, furniture, vehicle interior decoration and the like of a building. In particular, the present invention relates to a non-PVC-based decorative sheet that does not use a vinyl chloride resin sheet, and a decorative material using the same.

[0002]

2. Description of the Related Art Conventionally, as a decorative sheet used for the above-mentioned applications, a decorative sheet obtained by using a vinyl chloride resin sheet as a base material sheet and decorating it by printing, embossing or the like. No. 28-5036, No. 5
No. 8-14312). However, since a decorative sheet using a vinyl chloride resin sheet generates hydrochloric acid gas when burned at the time of disposal, a decorative sheet using another resin containing no chlorine is desired from the viewpoint of global environmental problems. became. Therefore, in recent years, as an alternative to such a PVC-based decorative sheet, an olefin-based decorative sheet using a polyolefin-based resin sheet such as polyethylene, polypropylene, or an olefin-based thermoplastic elastomer (JP-A-54-62255; Japanese Unexamined Patent Publication No. Hei 6-210808, Japanese Unexamined Patent Publication No. Hei 4-504384, Japanese Unexamined Patent Publication No. Hei 7-26038, etc.) have appeared.

[0003]

However, in a conventional decorative sheet using a polyolefin resin sheet as described above, when the decorative sheet is stretched by V-cut processing or the like,
The so-called necking in which the elongation is concentrated locally may occur. For this reason, whitening or cracks may occur, or a decorative sheet having an irregular pattern such as a conduit groove on the surface may open the groove (deformation of the irregular pattern) and impair the appearance of the design. there were. Such a problem at the time of bending was also observed in lapping. On the other hand, in the conventional decorative sheet as described above, when the temperature is increased for heating the sheet, the sheet may suddenly elongate. For this reason, the processing temperature range of embossing by heat is narrow, and the non-defective product rate may be reduced.

Accordingly, an object of the present invention is to provide a non-vinyl chloride decorative sheet using a polyolefin resin sheet without using a vinyl chloride resin, in which whitening and cracking due to necking occur during bending such as V-cutting or lapping. ,
It is an object of the present invention to provide a decorative sheet that does not cause appearance defects such as uneven pattern deformation, has a wide processing temperature range for hot embossing, and does not lower the yield rate. Another object is to provide a decorative material using such a decorative sheet.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, in the decorative sheet of the present invention, in a decorative sheet in which a polyolefin resin sheet is decoratively treated, a stress obtained by a tensile load test of the decorative sheet is obtained. In the strain curve, the yield point stress Yy and the inflection point stress Y at a point at which the stress decreases as the strain increases from the yield point stress Yy and then starts increasing.
The gradient G of the stress-strain curve at an intermediate point stress Ym as an intermediate point between i and i is -0.2 N / mm ² ·% or more. Further, the decorative sheet of the present invention has a configuration in which an uneven pattern is formed on the surface as a decoration process in the decorative sheet.

[0006] By adopting such a configuration, appearance defects such as whitening, cracking, and irregular pattern deformation due to necking do not occur during bending such as V-cutting and lapping, and hot embossing during manufacturing. The decorative sheet has a wide temperature range and does not decrease the yield rate. Further, since a vinyl chloride resin sheet is not used, the sheet is environmentally friendly.

The decorative material of the present invention has a configuration in which any one of the decorative sheets of the present invention is laminated on a substrate. As a result, even if it is bent, a decorative material having no appearance defects such as whitening, cracks, and irregular pattern deformation is obtained.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a decorative sheet and a decorative material of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view for explaining the definition of the gradient G in the stress-strain curve defined by the decorative sheet of the present invention, and FIG. 2 is a graph showing good (OK) and poor (NG) values for the gradient G. FIG. 3 and FIG. 4 are conceptual views showing stress-strain curves in the case, FIG. 3 and FIG. 4 are cross-sectional views illustrating some examples of various layer configurations of the decorative sheet of the present invention, and FIG. FIG. 6 is a cross-sectional view illustrating the decorative material of the present invention, and FIG. 6 is an explanatory diagram illustrating a pulling direction of a test piece.

[Summary] First, the decorative sheet S of the present invention comprises:
As shown in the various embodiments of FIG. 2, in a decorative sheet in which a polyolefin-based resin sheet 1 is decorated with a decorative layer 2 formed by printing or the like, and a concavo-convex pattern 3 formed by embossing or the like, the machine of the decorative sheet is used. As a physical property, a decorative sheet having a configuration in which the gradient G of the stress-strain curve measured by a tensile load at a certain point (intermediate point stress Ym) after the yield point stress Yy is equal to or more than the above-described specific value. is there.

[Gradient G] Stress-strain curve, descending
Yield inflection point stress, inflection point stress Yi, intermediate point stress Ym, and
To explain the gradient G derived therefrom conceptually.
This will be described with reference to FIG. First, the stress-strain curve is
Perform a tensile test on the test piece to apply a tensile load.
The vertical axis represents the stress Y applied to the test piece, and the strain X of the test piece.
Is a curve obtained when is plotted on the horizontal axis. Stress Y
Means that the (tensile) load applied to the test piece
It is a value divided by the initial cross-sectional area. On the other hand, the strain
Length L during measurement and initial length L before measurement₀Measure the difference with
Previous initial length L₀Divided by
Expressed in [%]. That is, the strain X is 100 × (L−
L₀) / L ₀[%]. For example, initial length 50mm
Is stretched 50 mm to 100 mm,
Percentage is 100%.

First, the yield point stress Yy is defined as the stress −
In the strain curve, initially, the slope (stress / strain) of the curve shows a constant or almost constant elastic deformation, the stress further increases, and the slope of the curve decreases from a certain positive value.
The point at which the slope of the curve finally becomes zero is defined as the yield point, and the stress at this yield point is the yield point stress. The yield point corresponding to the zero slope point is the (first) of the stress-strain curve.
It is the maximum point.

Next, the inflection point stress Yi is calculated as the yield point stress Yy
When the strain is further increased by further extending the measurement piece from the above, the stress decreases and the stress at which the stress starts to increase, that is, the stress at the point where the slope of the curve becomes zero again.

The intermediate point stress Ym is an intermediate point (in the stress, not the strain) between the yield point stress Yy and the inflection point stress Yi. That is, intermediate point stress Ym = (yield point stress Yy + inflection point stress Yi) / 2.

The gradient G is defined as the midpoint stress Ym.
Is the slope of the stress-strain curve in FIG. That is, the gradient G is ΔY / ΔX at the midpoint stress Ym. Since the curve at the midpoint stress Ym has a slope falling rightward, the slope G is a negative value. Note that a large gradient means that the absolute value of the gradient G is large and the value of the negative gradient G itself is small.

[0015] Even in the case of a decorative sheet using a polyolefin resin, the gradient G is set to -0.2 N / m.
By defining it as m ² ·% or more, favorable results can be obtained. That is, whitening due to necking, cracks, and appearance defects such as deformation of uneven patterns do not occur during bending such as V-cutting or lapping, and the processing temperature range of hot embossing during manufacturing is wide, and the yield rate does not decrease. I found out what a decorative sheet can do. Conversely, if the gradient G does not satisfy the above-mentioned rules, a favorable result cannot be obtained.

Incidentally, a preferable upper limit of the gradient G is zero. That is, the inclination is horizontal. When the gradient G is equal to or greater than zero, there is no clearly upwardly convex yield point stress Yy or clearly downwardly inflection point stress Yi.
The gradient G derived using y and the inflection point stress Yi is not defined. Further, the tensile direction of the test piece is preferably a direction in which the test piece is stretched at the time of bending using the decorative sheet. This is because the extending direction varies depending on the pattern and use of the decorative sheet. Therefore, as illustrated in FIG. 6, the pulling direction may be the flow direction x of the continuous band-shaped decorative sheet S, the horizontal direction y perpendicular to the flow direction, or another direction. . The direction in which the intended decorative sheet extends when it is actually bent may be determined with emphasis.

A stress-strain curve a conceptually illustrated in FIG. 2 shows one example of a decorative sheet of the present invention, and the stress-strain curve a has a preferable gradient G defined by the present invention. FIG. On the other hand, stress-
The distortion curves b and c are curves that do not correspond to the decorative sheet of the present invention. Looking at these, the gradient G, which is the gradient at the midpoint stress Ym from the yield point stress Yy to the inflection point stress Yi, shows that the stress-strain curve a is gentler than the stress-strain curves b and c. As you can see. With a decorative sheet giving the stress-strain curves b and c, good bending workability and hot embossing suitability cannot be obtained as intended.

The decorative sheet using the vinyl chloride resin sheet had a stress-strain curve d. When this stress-strain curve d is compared with a stress-strain curve a conceptually showing one example of the stress-strain curve of the decorative sheet of the present invention, the yield point in the case of the stress-strain curve a The ratio of the stress difference between the stress Yy and the inflection point stress Yi to the yield point stress Yy is large. However, focusing on the gradient G, it has been found that the intended effect can be obtained if the gradient G is equal to or more than the specific value.

Hereinafter, the layer structure of the decorative sheet will be further described.

[Summary of Layer Structure] The decorative sheet of the present invention, which satisfies the above-mentioned specific mechanical properties, is a decorative sheet or a decorative sheet of a polyolefin resin sheet. Is not particularly limited. However, since there is no deformation of the concave and convex pattern such that the conduit groove is opened at the time of bending, and the processing suitability when hot embossing the concave and convex pattern is good, the cosmetic having the concave and convex pattern formed by hot embossing as a decorative treatment. Sheets are particularly suitable. Of course, as the decorative sheet of the present invention, in addition to such uneven patterns, uneven patterns formed by other methods,
It goes without saying that a decorative sheet such as a decorative layer formed by printing or the like may be subjected to a conventionally known decorative treatment.

Here, the decorative sheet S of the present invention illustrated in FIG. 3 will be described. First, the decorative sheet S in FIG.
Transparent polyolefin resin sheet 1 as base sheet
Is a decorative sheet on which a decorative layer 2 is formed by printing or the like on the back side. Further, the decorative sheet S in FIG.
In the decorative sheet of (A), a concave / convex pattern 3 such as a wood channel groove pattern is formed on a polyolefin resin 1 serving as a surface layer by hot embossing or the like. 3 (A) and 3 (B) show a decorative sheet having a single-layered base material sheet, the following FIGS. 3 (C) and 3 (D) show decorative sheets.
As an example of a multi-layer configuration having more than one layer, a base sheet is an example of a decorative sheet having a two-layer configuration. For example, the decorative sheet S in FIG.
Means that the lower base sheet is a polyolefin resin sheet 1
The decorative layer 2 is formed thereon by printing or the like, and a transparent surface sheet 4 as a base material sheet on the front side is laminated on the surface on which the decorative layer is formed by dry lamination, T-die extrusion, or the like. It is a decorative sheet having the configuration described above. The topsheet 4 may be a polyolefin resin 1 as in the case of the base material sheet on the back side, but may be another non-vinyl chloride resin sheet if necessary. FIG. 3 (D) is a decorative sheet having a configuration in which a concavo-convex pattern 3 is further formed on the surface of the top sheet as compared to FIG. 3 (C). 3 (C) and (D)
As described above, the polyolefin resin sheet 1 below the decorative layer 2 may be transparent or opaque, but usually has many colored opaque.

[Polyolefin-based resin sheet] Polyolefin-based resins include high-crystalline materials such as polyethylene (low density or high density), polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, and propylene-butene copolymer. Non-elastomeric polyolefin-based resins or various olefin-based thermoplastic elastomers are used. Polyolefin resin sheet
Among these, a sheet that satisfies the above-mentioned mechanical properties when used as a decorative sheet may be selectively used after a measurement test.

As the olefin-based thermoplastic elastomer, for example, the following can be used.

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

Among the olefinic thermoplastic elastomers of this type, isotactic polypropylene, which is less likely to cause so-called "necking" and has good suitability for molding or embossing by heating and pressurizing, is exemplified by isotactic polypropylene. The mixing ratio with the atactic polypropylene is 5% by weight or more and 50% by weight or less by weight ratio of the atactic polypropylene. The polypropylene-based olefin-based thermoplastic elastomer itself is already known, but when used in a conventionally known application such as a packaging container, the weight ratio of the soft segment atactic polypropylene is 5 to emphasize strength. Less than% by weight was exclusively used. However, when this is applied to a novel use such as forming into a three-dimensional shape or a concavo-convex shape or embossing, necking occurs as described above, and good processing cannot be performed. Therefore, contrary to the conventional design of the composition, in the olefin-based thermoplastic elastomer of polypropylene, by setting the weight ratio of the atactic polypropylene to 5% by weight or more, embossing or three-dimensional shape, or It is possible to eliminate non-uniform sheet deformation due to necking in forming an uneven article surface shape, and resulting defects such as wrinkles and pattern distortion. Particularly, the case where the weight ratio of the atactic polypropylene is 20% by weight or more is preferable. On the other hand, if the weight ratio of atactic polypropylene increases too much,
The sheet itself is easily deformed, and when the sheet is passed through a printing press, the sheet is deformed, a pattern is distorted, and defects such as misregistration in multicolor printing easily occur. Further, it is not preferable because it is easily broken during molding. As the upper limit of the weight ratio of the atactic polypropylene, the decorative layer is printed using a normal rotary printing machine such as rotary gravure printing, and embossing of the sheet, vacuum forming, V-cut processing, simultaneous lamination of injection molding, etc. 50 to hire
% By weight, more preferably 40% by weight or less.

(2) A thermoplastic elastomer comprising an ethylene-propylene-butene copolymer resin. Here, as the butene, any of the three structural isomers of 1-butene, 2-butene and isobutylene can be used. Preferred specific examples of the ethylene-propylene-butene copolymer, which is a random copolymer and partially includes an amorphous portion, include the following (i) to (iii). (i) Those described in JP-A-9-111055. It is a random copolymer of a terpolymer of ethylene, propylene and butene. The weight ratio of the monomer components is 90% by weight or more of propylene. The melt flow rate is preferably 1 to 50 g / 10 minutes at 230 ° C. and 2.16 kg. And, for 100 parts by weight of such a ternary random copolymer, 0.01 to 50 parts by weight of a transparent nucleating agent containing a phosphate aryl ester compound as a main component,
It is obtained by melting and kneading 0.003 to 0.3 parts by weight of a fatty acid amide having 12 to 22 carbon atoms. (ii) Those described in JP-A-5-77371. this is,
80 to 0% by weight of crystalline polypropylene is added to 20 to 100% by weight of an amorphous polymer having a propylene content of 50% by weight or more, which is a terpolymer of ethylene, propylene and 1-butene. It is. (iii) Those described in JP-A-7-316358. This is a terpolymer of ethylene, propylene, and 1-butene, and the content of propylene and / or 1-butene is 50% by weight or more and 20 to 100% by weight of the low crystalline polymer. 0.5% by weight of an oil gelling agent such as N-acylamino acid amine salt or N-acylamino acid ester is added to a composition containing 80 to 0% by weight of a crystalline polyolefin such as isotactic polypropylene. It becomes.

The ethylene-propylene-butene copolymer resin may be used alone, or may be used in any of the above (i) to (iii).
If necessary, another polyolefin-based resin may be mixed and used.

(3) As described in JP-B-53-21021, (A) an olefin polymer (crystalline polymer) such as polyethylene, polypropylene and polymethylpentene is used as a hard segment, and (B) a partial cross-linking Monoolefin copolymer rubbers such as ethylene-propylene copolymer rubber and unsaturated ethylene-propylene-non-conjugated diene terpolymer rubber are used as soft segments, and these are uniformly blended and mixed. . In addition,
Monoolefin rubber / olefin polymer = 50 / 50-
Mix at a ratio of 90/10 (weight ratio).

(4) As described in JP-B-53-34210, etc., (B) an uncrosslinked monoolefin copolymer rubber (soft segment) and (A) an olefin copolymer (crystalline, hard segment) ) And a cross-linking agent, and is heated to apply shear stress to dynamically partially cross-link an olefin-based elastomer. (B) monoolefin rubber / (A) olefin copolymer = 60/40 to 80/20
(Weight ratio).

(5) As described in JP-B-56-15741, (A) isotactic polypropylene, propylene-ethylene copolymer, propylene-butene-1
A peroxide-decomposable olefin polymer (hard segment), which decreases its molecular weight when mixed and heated with a peroxide such as a copolymer to increase fluidity, and (B) ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene Peroxide-crosslinked monoolefin copolymer rubber (soft segment), which crosslinks and reduces fluidity by mixing and heating with a peroxide such as an original copolymer rubber, (C)
Peroxide non-crosslinked hydrocarbon rubber (soft segment / fluidity-modifying component) that does not crosslink even when mixed and heated with peroxides such as polyisobutylene and butyl rubber and has constant fluidity, and (D) paraffinic and naphthene An olefin-based elastomer obtained by mixing a mineral oil-based softener such as an oil-based or aromatic oil-based softener and dynamically heat-treating the mixture in the presence of an organic peroxide. (A) is 90 to 40 parts by weight, (B) is 10 to 60 parts by weight.
(A) + (B) = 100 parts by weight,
(C) and / or (D) have a compounding ratio of 5 to 100 parts by weight.

(6) An olefin-based thermoplastic elastomer comprising an ethylene-styrene-butylene copolymer as described in JP-A-2-139232.

(7) The olefin-based thermoplastic elastomer according to the above (1) to (6), having a hydroxyl group and / or a carboxyl group as a polar group. For example, an olefin-based thermoplastic elastomer having a hydroxyl group introduced by graft polymerization of an ethylene-vinyl alcohol copolymer or the like and a carboxyl group introduced by a copolymer of maleic acid, fumaric acid, itaconic acid or the like is used. Either one or both of the hydroxyl group and the carboxyl group may be used in combination, and these polar groups have an effect of improving adhesion to other layers such as a decorative layer and an adhesive layer.

The above-mentioned polyolefin resin can be formed into a sheet (film) by a film forming method such as a calendering method, an inflation method or a T-die extrusion method. The thickness of the sheet to be used depends on the application and the like, but is about 20 to 300 μm.

These polyolefin-based resin sheets can be used either as stretched sheets or unstretched sheets, but the unstretched sheets are more suitable for molding such as V-cutting and lapping. Various additives such as a filler, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer are added to the sheet as needed.

For example, powders such as calcium carbonate, barium sulfate, clay, and talc are used as the filler. Add an appropriate amount as needed.

In particular, in applications where improvement in weather (light) resistance is required, one or preferably both of a benzotriazole-based ultraviolet absorber and a hindered amine radical scavenger and the like are added as a weather-resistant agent. Thus, it is preferable to improve weather (light) resistance. The amount of addition is usually 0.1.
It is in the range of 1 to 5% by weight.

The polyolefin resin sheet includes:
If necessary, one or both surfaces thereof may be subjected to an easy adhesion treatment such as a corona discharge treatment, a plasma treatment, an ozone treatment, and formation of an easy adhesion layer.

[Decoration treatment] As the decoration treatment for the polyolefin resin sheet, coloring (transparent or opaque coloring) by adding a coloring agent such as a pigment or dye to the resin sheet itself [for example, FIG. 2 (C) and FIG. ), Etc.], the application of the decorative layer 2 by printing or the like expressing a pattern or the like (see FIGS. 2A to 2D and FIG. 4), and the shaping of the uneven pattern 5 by embossing or the like [ 2 (B) and 2 (C), FIG.
(B)). In this way, the decoration process
Conventionally well-known various decorative treatments on a general decorative sheet may be used. Various decoration processes may be used in combination as appropriate depending on the application.

For example, as shown in FIGS. 3C and 3D, in the case of a decorative sheet having a multi-layer structure in which a plurality of base sheets are laminated, the decorative treatment for the polyolefin resin sheet is performed by using a polyolefin resin sheet. After decorating another layer (for example, a surface sheet) other than the resin sheet, the other layer is laminated, or the other layer is laminated on the polyolefin resin sheet and then decorated on another layer. As a result, the polyolefin-based resin sheet may be subjected to decorative treatment.

(Addition of coloring agent) As coloring agents, inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine blue, cobalt blue, titanium yellow, graphite, carbon black, isoindolinone, Hansa Yellow A Organic pigments (or dyes) such as quinacridone, permanent red 4R, phthalocyanine blue, indathrene blue RS, and aniline black; metal pigments such as aluminum and brass; foil powders such as titanium dioxide-coated mica and basic lead carbonate And pearlescent (pearl) pigments. These are added and dispersed as powder or flaky foil pieces. The coloring by the coloring agent may be transparent coloring or opaque (concealing) coloring. However, when the resin sheet is colored, if a decorative layer is provided below, the resin sheet is colored so as not to impair the transparency of the decorative layer. The same applies to the case where the topsheet is decorated by coloring with the addition of a coloring agent.

(Application of Decorative Layer) The decorative layer 2 is formed by a printing method, hand-drawing, or the like. As a printing method, for example, it is formed with ink by a known printing method such as gravure printing, offset printing, silk screen printing, and transfer printing from a transfer sheet. Further, in the case of a solid pattern on the entire surface, it can be formed with a coating material by a known coating method such as gravure coating or roll coating. As the pattern of the decoration layer, wood grain pattern,
There are a stone pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, and a solid surface. The decorative layer may be provided on the front surface, the back surface, both the front and back surfaces of the polyolefin resin sheet, or between the layers when the decorative sheet is composed of a multi-layered base sheet. Further, in the case of a multi-layer, it is also possible to form a decorative sheet by forming the surface sheet by printing or the like on the surface sheet which is the substrate sheet on the front side and then laminating the surface sheet with the (back side) substrate sheet. As the ink (or) paint, as a binder, chlorinated polyolefin such as chlorinated polyethylene, chlorinated polypropylene, polyester resin, urethane resin, acrylic resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, cellulose resin, And the like, or one kind or a mixture of two or more kinds. To this, one or more known colorants as described above are added.

When printing directly on a polyolefin resin sheet, chlorinated polyolefin, urethane resin or the like is preferable as a binder in terms of adhesiveness. However, if a primer layer is formed on the printing surface side, other binders may be used. Gives sufficient adhesiveness. In addition, as the primer layer, acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin, urethane resin, chlorinated polypropylene, chlorinated polyethylene, and the like are used. In addition, corona discharge treatment, easy adhesion treatment such as plasma treatment, or
More preferably, the primer layer may be formed after performing these easy adhesion treatments.

The decoration layer may be a metal thin film layer. The metal thin film layer 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 layer may be provided on the entire surface or partially in a pattern.

(Shaping of Uneven Pattern) As the uneven pattern 3,
There is no particular limitation. Any suitable for the purpose of the decorative sheet may be used. The uneven pattern is, for example, a wood grain board conduit groove, a stone board surface unevenness (granite cleavage plane or the like), a cloth surface texture, a satin finish, a grain, a hairline, a linear groove, or the like. The uneven pattern may be a combination of these. The shaping of the concavo-convex pattern is performed by hairline processing, sandblasting, embossing, or the like. For example, the embossing is performed by pressing an embossing plate on the surface of a heat-softened resin sheet such as a polyolefin resin sheet using a hot press type sheet-fed or rotary embossing machine. In particular, the decorative sheet of the present invention has good suitability for embossing by heating, so shaping by embossing is preferred. Of course, there may be an uneven pattern by another shaping method, for example, an uneven pattern formed simultaneously with the formation of the surface sheet. Further, the uneven pattern is usually on the front side of the decorative sheet, but may be present on the interlayer and on the back side.

(Other Decoration Processing) Although not shown, if necessary, the concave portions of the concavo-convex pattern 3 may be formed by a known wiping method (see Japanese Patent Publication No. 58-14312).
A colored portion can be formed by filling a colored ink.
In the wiping method, a colored ink is applied to the entire surface of the concave and convex pattern, and then the ink in the convex portion is scraped off and the colored ink is left in the concave portion. Wiping is performed by the dokuda blade method,
Any of conventional wiping methods such as a roll coating method may be used. The coloring ink can be the same as the decorative layer formed by printing. However, from the viewpoint of abrasion resistance, a material using a two-component curable urethane resin as a binder is preferable.

(Other Decorating Process) Although not shown, the decorating process includes a process of forming an overcoat layer on the surface of the decorative sheet for adjusting the gloss and imparting a design such as a feeling of painting. However, since the overcoat layer is the outermost surface layer of the decorative sheet, it is usually provided for the purpose of improving the surface physical properties such as scratch resistance and stain resistance rather than decorative treatment. The overcoat layer may be formed by coating with a known paint such as an acrylic resin or a urethane resin.

[Surface Sheet] In the case of the structure having the topsheet 4, the above-mentioned polyolefin resin sheet can be used as the topsheet. Also, besides the polyolefin-based resin sheet, if it is a chlorine-free resin sheet and satisfies the above mechanical properties as a decorative sheet,
An appropriate resin sheet can be used depending on the use of the decorative sheet. For example, acrylic resin, ethylene-vinyl alcohol copolymer resin, thermoplastic polyester resin, etc. The thickness of the topsheet depends on the application, but is usually 20 to 1
It is about 00 μm.

To laminate the topsheet with the base sheet, T-die extrusion coating (extrusion coating), fusion by hot pressing, or use of an adhesive such as a two-component curable urethane resin or polyester resin is used. It is good according to dry lamination. As in the decorative sheet S illustrated in FIG. 3, the topsheet 4 is laminated on the polyolefin resin sheet 1 as a base sheet via an adhesive layer 5. Although the adhesive layer 5 is not shown in FIGS. 3 (C) and 3 (D), it is mainly for conceptual explanation of the decoration process, and is used for laminating the top sheet and the base sheet. The adhesive layer is omitted, including whether or not it is used.

[Adhesive Layer] The decorative sheet may optionally be provided with an adhesive layer for adhering the decorative sheet to the adherend on the side of the adhering surface, if necessary. For the adhesive layer, a conventionally known adhesive such as a thermoplastic resin such as polyamide, a curable resin such as a thermosetting resin such as a urethane resin, or the like may be used depending on the application. Adhesion forms include heat fusion, adhesion, and solvent evaporation. Note that the adhesive layer may be formed by a known printing or coating method such as gravure printing or roll coating.

[Cosmetic Material] The decorative material of the present invention is obtained by applying the above-described decorative sheet S of the present invention to the surface of the base material 6 as an adherend, as in the decorative material D illustrated in the cross-sectional view of FIG. It is a decorative material having a laminated configuration. In FIG. 4, the base material 6 and the decorative sheet S
The illustration of the adhesive layer interposed between them as appropriate is omitted. In this case, the adhesive layer may be supplied as a component of the decorative sheet, or may be supplied by being applied to the base material side.

[Substrate] The substrate as an adherend of the decorative sheet of the present invention or the substrate 6 in the decorative material of the present invention is not particularly limited, and for example, the following substrates are used. it can. That is, examples of the substrate include plate materials such as flat plates and curved plates of various materials, three-dimensional articles, sheets (or films), and the like. For example, wood veneer, wood plywood, particle board, wood material such as wood fiber board such as MDF (medium density fiber board), wood board material used as three-dimensional article, plate material such as iron and aluminum, three-dimensional article or Ceramics used as metal materials used as sheets, ceramics such as glass and ceramics, non-cement ceramic materials such as gypsum, non-ceramic ceramic materials such as ALC (lightweight cellular concrete) plates, etc. -Based materials, acrylic resin, polyester resin, polystyrene resin, polyolefin resin such as polypropylene, ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenol resin, vinyl chloride resin, cellulose resin, rubber and other plate materials, three-dimensional shape A resin material used as an article or sheet, or High-quality paper to be used as,
Examples include paper such as Japanese paper, nonwoven fabric or woven fabric made of fibers such as carbon, asbestos, glass, and synthetic resin.

[Laminating method of decorative sheet on substrate] As a method of laminating decorative sheet on these various substrates, for example, laminating by pressing a plate-shaped substrate with a pressure roller via an adhesive is used. As described in JP-B-50-19132, JP-B-43-27488, etc., after a decorative sheet is placed between the male and female molds for injection molding, the molten resin is injected and filled into the mold. A so-called simultaneous injection molding laminating method in which a decorative sheet is adhered and laminated on the surface of the resin molded article at the same time as the molding thereof, as described in JP-B-56-45768, JP-B-60-58014, etc. A decorative sheet on the surface of a three-dimensional article such as an article, facing or placed via an adhesive therebetween, and laminating the decorative sheet on the surface of the three-dimensional article by a pressure difference due to vacuum suction from the three-dimensional article side; So-called vacuum pre Lamination method, JP-B-61-5
No. 895, Japanese Patent Publication No. 3-2666, etc., while supplying a decorative sheet through an adhesive in the long axis direction of a columnar base material such as a cylinder, a polygonal column, etc. There is a so-called lapping method in which decorative sheets are successively pressed and laminated on a plurality of side surfaces constituting a columnar substrate by rollers having different directions.

As a further processing method for a decorative sheet obtained by laminating decorative sheets, Japanese Utility Model 15-311
No. 22, JP-A-48-47972, a decorative sheet is first laminated on a plate-like base material with an adhesive therebetween to form a decorative sheet, and the surface opposite to the decorative sheet is used. To
Cut a V-shaped or U-shaped groove reaching the interface between the decorative sheet and the plate-shaped substrate, and then apply an adhesive in the groove and bend the groove to form a box or column. Is a so-called V-cut or U-cut processing method.

In particular, as a method of finally bonding the decorative sheet of the present invention to a three-dimensional object having irregularities, of the above-mentioned methods, a V-cut processing method and the like are preferable. Processing is preferred.

[Use of Decorative Sheet and Decorative Material] The decorative sheet and the decorative material of the present invention are subjected to predetermined molding processing as required, and used for various purposes. For example, interior decoration of buildings such as walls, ceilings, floors, window frames, doors, surface makeup of fittings such as handrails,
Surface makeup of furniture or cabinets of light electric / OA equipment, interior of vehicles such as cars and trains, interior of aircraft, interior of ships, makeup of window glass, etc. A decorative material whose base material is a plate material is used as a decorative plate or the like.

[0056]

EXAMPLES The decorative sheet of the present invention will be further described below with reference to examples and comparative examples.

Example 1 As shown in FIG. 4A, a decorative sheet S was prepared as follows. An opaque colored polyolefin-based resin sheet 1 made of an ethylene-propylene random copolymer having a thickness of 60 μm is used as a base sheet, and a corona discharge treatment is applied to one side of the base sheet, and then an acrylic urethane-based resin is used as a binder resin. The decorative layer 2 was formed by gravure printing with the used coloring ink to obtain a printed sheet. Next, a transparent surface sheet 4 of 80 μm thick made of a polypropylene-based polyolefin-based resin composed of a mixture of crystalline polypropylene and hydrogenated styrene-butadiene rubber was applied to the printing sheet by dry lamination using a polyester-based adhesive. Was laminated on the surface on which the decorative layer was formed via the adhesive layer 5 to obtain a decorative sheet S of the present invention as shown in the sectional view of FIG.

When the stress-strain curve of this decorative sheet was measured by a tensile tester, the curve was as shown by curve a in FIG. 2, and the obtained gradient G was -0.07 N / mm ² ···
%Met. As shown in the explanatory view of FIG. 6, the tensile direction of the test piece was set to the horizontal direction y perpendicular to the flow direction x of the continuous band-shaped decorative sheet (the same applies to Example 2 and Comparative Examples). Further, this decorative sheet was laminated on a Rawan plywood with a urethane adhesive to form a decorative plate. This veneer is V
As a result of cutting, no whitening or cracking occurred in the bent portion, and the bending workability was good.

[Example 2] In Example 1, the decorative sheet after lamination of the topsheet was formed into an irregular pattern of a wood channel groove pattern by hot embossing using an embossing roller.
A decorative sheet S as shown in FIG. The embossing was performed stably and favorably without the sheet being stretched too much. The gradient G of the decorative sheet was the same as in Example 1. Further, similarly to Example 1, this decorative sheet was laminated on a Lauan plywood with a urethane-based adhesive to form a decorative plate. When this decorative board was subjected to V-cut processing, no whitening or cracking occurred in the bent portion, and further, no appearance defect due to deformation of the uneven pattern called opening of the conduit groove occurred, and the bending workability was good. there were.

[Comparative Example 1] In Example 1, the polyolefin resin sheet 1 as the base sheet was changed to a resin sheet having the same resin but different copolymerization ratio and the like, and the top sheet 4 was also made of the same resin. However, a decorative sheet was produced in the same manner as in Example 1, except that the resin composition was changed to a resin sheet having a different compounding ratio of the rubber component. The stress-strain curve of this decorative sheet is as shown by curve c in FIG. 2, and the gradient G is -0.3 N / m
m ² ·%. Further, this decorative sheet was laminated on a Rawan plywood with a urethane adhesive to form a decorative plate. When this decorative board was subjected to V-cut processing, whitening and cracks occurred at the bent portion, and the bending workability was poor.

[0061]

According to the decorative sheet of the present invention, it is possible to prevent whitening and cracks from occurring in the bent portion during bending such as V-cutting and lapping. In addition, when there is a concavo-convex pattern such as a wood-grain conduit groove pattern, deformation of the concavo-convex pattern can be prevented, for example, by opening the groove. As a result, appearance defects do not occur even when bending is performed. In addition, when forming an uneven pattern such as a wood grain conduit groove by hot embossing, the processing temperature range of embossing is also widened, so that the defective rate is not increased and the non-defective rate is improved. Furthermore,
Since no vinyl chloride resin sheet is used, the sheet is also environmentally friendly. According to the decorative material of the present invention, the effects of the decorative sheet described above can be obtained. As a result, the appearance is good and the yield is good.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating the definition of a gradient G in a stress-strain curve defined by a decorative sheet according to the present invention.

FIG. 2 shows a good (OK) and bad (N) gradient G
Explanatory drawing which shows notionally the stress-strain curve in case of G).

FIG. 3 is a cross-sectional view illustrating some of the layer configurations of the decorative sheet of the present invention.

FIG. 4 is a cross-sectional view illustrating one embodiment of the decorative sheet of the present invention.

FIG. 5 is a cross-sectional view illustrating one embodiment of the cosmetic material of the present invention.

FIG. 6 is an explanatory diagram for explaining a pulling direction of a test piece.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polyolefin resin sheet 2 Decorative layer 3 Concavo-convex pattern 4 Surface sheet 5 Adhesive layer 6 Base material D Cosmetic material G Gradient X Strain Y Stress Yi Inflection point stress Ym Intermediate point stress Yy Yield point stress S Decorative sheet x Flow direction y Horizontal direction perpendicular to the flow direction

Continued on front page F term (reference) 4F071 AA14 AF13Y AG22 AH03 AH11 AH19 BC01 BC02 BC08 BC09 4F100 AK07B AK25C AK51C AK51G AK64 AL01C AL03 AP02 AS00C AT00A BA03 BA07 BA10A BA10C CB00 DD01 GB07 H33B01 J02 GB07 BB121 BB141 BB171 FD096 GF00 GL00 GN00

Claims (3)

[Claims] 1. A decorative sheet on which a polyolefin-based resin sheet has been subjected to a decoration treatment, wherein a yield point stress Yy is obtained by a stress-strain curve obtained by a tensile load test of the decorative sheet.
The gradient G of the stress-strain curve at an intermediate point stress Ym as an intermediate point between the yield point stress Yy and an inflection point stress Yi at a point where the stress decreases and then increases as the strain increases. Is -0.2 N / mm ² ·% or more. 2. The decorative sheet according to claim 1, wherein an irregular pattern is formed on the surface as a decoration treatment. 3. The decorative sheet according to claim 1 or 2,
A decorative material laminated on a substrate.