JP2000033678A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve scratch resistance along with bending processing aptitude in an olefinic decorative sheet. SOLUTION: A transparent surface sheet 2 comprising a polyolefinic resin is laminated on a colored base material of a polyolefinic resin and the surface sheet is constituted of an olefinic thermoplastic elastomer comprising a mixture of a crystalline polyolefin resin and a styrenic thermoplastic elastomer. As decoration treatment, the decorative layer 3 between the base material sheet and the surface sheet or an embossed pattern 4 is appropriately formed. Further, if an ultraviolet absorber having a hydroxyl group is added to the surface sheet and an ultraviolet absorber bleed blocking layer comprising a urethane resin is formed on the surface sheet, weatherability also becomes good.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[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. It has become. 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, and an olefin-based thermoplastic elastomer (Japanese Patent Laid-Open No. 54-62255,
JP-A-6-210808, JP-A-4-504384, JP-A-7-26038, etc.) have appeared.

[0003]

However, a decorative sheet having a structure in which a topsheet is laminated on a base sheet has the following problems. When a crystalline polyolefin resin such as a single high-density polyethylene or isotactic polypropylene is used as a thermoplastic resin constituting a transparent or translucent surface sheet serving as the outermost surface layer, bending processing such as V-cut processing is performed. Occasionally, whitening and cracking were likely to occur on the topsheet. This is because "necking" occurs in which the elongation at the time of applying tensile stress becomes non-uniform, and local stress concentration occurs. Also, as disclosed in JP-A-10-71683,
When the topsheet is made of an olefin-based thermoplastic elastomer having isotactic polypropylene as a hard segment and atactic polypropylene as a soft segment, the problem of whitening and cracking during the bending process is improved, but the scratch resistance is still weak As it is, there is a problem in applications requiring surface strength.

[0004]

Therefore, in order to solve the above problems, in the decorative sheet of the present invention, a transparent surface sheet made of a polyolefin resin is provided on the surface of a colored base sheet made of a polyolefin resin. , And at least the topsheet is an olefin-based thermoplastic elastomer made of a mixture of a crystalline polyolefin resin and a styrene-based thermoplastic elastomer. As a result, a decorative sheet having good bending workability for preventing whitening and cracking during bending and having good scratch resistance can be obtained. In addition, the decorative sheet of the present invention has a structure in which the surface sheet contains an ultraviolet absorber having a hydroxyl group, and an ultraviolet absorber bleed blocking layer is formed on the surface sheet. . As a result, since the ultraviolet absorbent has a hydroxyl group, the ultraviolet absorbent bleed blocking layer formed on the topsheet prevents a reduction in the effect of the ultraviolet absorption effect due to bleed-out, and provides a weather-resistant decorative sheet.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a decorative sheet according to the present invention will be described with reference to the drawings.

[Outline] First, in the cross-sectional view of FIG. 1, some examples of various forms that the decorative sheet S of the present invention can take are illustrated. The decorative sheet S of FIG. 1 (A) has a transparent surface sheet 2 made of the specific polyolefin resin on the surface of a colored base sheet 1 made of a polyolefin resin.
Shows a form in which is laminated. Further, the decorative sheet S in FIG. 1B has a form in which the decorative layer 3 is provided between the base sheet 1 and the top sheet 2 as compared with the form in FIG. The decorative sheet S of FIG. 1C has a configuration in which the surface sheet 2 has an uneven pattern 4 on the surface of the configuration of FIG.

In the decorative sheet of the present invention, the polyolefin resin constituting the topsheet 2 is an olefin thermoplastic elastomer comprising a mixture of a crystalline polyolefin resin and a styrene thermoplastic elastomer. Incidentally, the olefin-based thermoplastic elastomer,
It may be used as a polyolefin resin constituting the base sheet.

[0008] The decorative sheet S of the present invention has been subjected to some decoration processing, and coloring of the base sheet is one type of decoration processing. Also, the decoration process is not particularly limited,
For example, as shown in FIG.
And the like, and the formation of the decorative layer 3 by printing a pattern on the surface sheet 2 or the like, as shown in FIG. Alternatively, in addition to the base sheet 1, the coloring treatment by pigment addition or the like may be performed on the top sheet 2.

Further, the decorative sheet of the present invention is further provided on the top sheet 2 as in the embodiment illustrated in the sectional view of FIG.
An ultraviolet absorbent bleed blocking layer 5 may be provided. In this case, it is preferable that the topsheet contains an ultraviolet absorber having a hydroxyl group.

Hereinafter, the decorative sheet of the present invention will be described in more detail.

[Base Sheet] First, the base sheet 1 is a colored sheet made of a polyolefin resin.
Examples of the polyolefin resin include highly crystalline non-elastomeric polyolefin resins such as polyethylene (low density or high density), polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer and propylene-butene copolymer. Resins or various olefinic thermoplastic elastomers are used. The base sheet may be a specific polyolefin-based resin listed in the surface sheet described later, or a sheet having the same composition as the sheet used for the surface sheet. However, since the substrate sheet does not require scratch resistance, another polyolefin resin may be used. However, in consideration of bending workability, an olefin-based thermoplastic elastomer is preferable from the viewpoint of moldability of the entire decorative sheet. As the olefin-based thermoplastic elastomer, for example, the following can be used.

[0012] Japanese Patent Publication No. Hei 6-23278,
(A) As a soft segment, the number average molecular weight Mn is 2
An atactic polypropylene soluble in boiling heptane having a weight average molecular weight Mw of not less than 5,000 and a ratio of weight average molecular weight Mw to number average molecular weight Mn of 7 to 10 to 90% by weight;
As a hard segment, the melt index is 0.1
Soft polypropylene consisting of a mixture of ４4 g / 10 min boiling heptane-insoluble isotactic polypropylene 90-10 wt%. Among olefin thermoplastic elastomers of this type, those that are less likely to cause so-called "necking" and have good suitability for molding or embossing by heating and pressing are isotactic polypropylene and atactic polypropylene. And the mixture ratio of the isotactic polypropylene and the atactic polypropylene is 5% by weight or more and 50% by weight or less by weight of the atactic polypropylene.

[0013] The olefin-based thermoplastic elastomer itself of polypropylene is already known, but when used in a conventionally known application such as a packaging container, the weight of the atactic polypropylene as a soft segment is emphasized in order to emphasize strength. Those with a ratio of less than 5% by weight were 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 composition design, the weight ratio of atactic polypropylene is set to 5% by weight or more in a polypropylene-based olefin-based thermoplastic elastomer. In addition, it is possible to eliminate defects such as non-uniform sheet deformation due to necking when forming an uneven article surface shape, and resulting wrinkles and picture distortions. In particular, the weight ratio of atactic polypropylene is 2
The case of 0% by weight or more is good. On the other hand, if the weight ratio of the atactic polypropylene increases too much, the sheet itself is easily deformed, the sheet is deformed when the sheet is passed through a printing machine, the pattern is distorted, or the register is not registered in the case of multicolor printing. And the like 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 and the like are printed using a normal rotary printing machine such as rotary gravure printing, and embossing of the sheet, vacuum forming, V-cut processing,
50% by weight when using injection molding simultaneous lamination
Or less, more preferably 40% by weight or less.

A thermoplastic elastomer comprising an ethylene-propylene-butene copolymer resin. Here, as the butene, 1-butene, 2-butene and isobutylene are used.
Any of the structural isomers can be used. The copolymer is a random copolymer and partially includes an amorphous portion. Preferred specific examples of the ethylene-propylene-butene copolymer 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 the above (i) to (iii).
If necessary, another polyolefin-based resin may be mixed and used.

As described in JP-B-53-21021, (A) an olefin polymer (crystalline polymer) such as polyethylene, polypropylene or polymethylpentene is used as a hard segment, and (B) a partially crosslinked ethylene- Propylene copolymer rubber, unsaturated ethylene-propylene-
An olefin-based elastomer obtained by using a monoolefin copolymer rubber such as a non-conjugated diene terpolymer rubber as a soft segment, and uniformly mixing and mixing these. Incidentally, monoolefin rubber / olefin polymer = 50/50 to 90
/ 10 (weight ratio).

As described in JP-B-53-34210 and the like, (B) uncrosslinked monoolefin copolymer rubber (soft segment) and (A) olefin copolymer (crystalline, hard segment) are crosslinked. An olefin-based elastomer obtained by mixing with an agent, heating and applying shear stress to dynamically partially cross-link. (B) Monoolefin rubber / (A)
Olefin copolymer = 60/40 to 80/20 (weight ratio).

As described in JP-B-56-15741, (A) mixing with a peroxide such as isotactic polypropylene, propylene-ethylene copolymer, propylene-butene-1 copolymer and heating reduces the molecular weight. Mixing and heating with a peroxide-decomposable olefin polymer (hard segment) that increases fluidity and (B) a peroxide such as ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene terpolymer rubber, etc. Mixes with peroxides such as peroxide-crosslinked monoolefin copolymer rubber (soft segment), which crosslinks and reduces fluidity, (C) polyisobutylene, butyl rubber, etc.
Peroxide non-crosslinked hydrocarbon rubber (soft segment and fluidity-modifying component) that does not crosslink even when heated and does not change fluidity, and (D) mineral oils such as paraffinic, naphthenic, and aromatic An olefin-based elastomer obtained by mixing a 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.

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

The above olefinic thermoplastic elastomer 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 of these hydroxyl groups and carboxyl groups,
Alternatively, these polar groups may be used in combination, and these polar groups have an effect of improving the adhesiveness to other layers such as a printing ink layer 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 calender method, an inflation method, and 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, usually about 50 to 100 μm. These polyolefin-based resin sheets can be used in any of a stretched sheet and an unstretched sheet.
The unstretched sheet has better molding suitability (bending workability) such as V-cut processing.

(Coloring of the base sheet) It can be said that coloring the base sheet is a kind of decoration treatment. However, if the coloring is performed by kneading a coloring agent such as a dye or a pigment into the resin of the base sheet, the coloring is performed. good. The coloring may be transparent coloring or concealing coloring.
Colorants include titanium white, zinc white, red stalk, vermilion, ultramarine,
Inorganic pigments such as cobalt blue, titanium yellow, graphite, and carbon black; organic pigments (or dyes) such as isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, Indaslenbri RS, and aniline black , Aluminum, brass, and other metal pigments; titanium dioxide-coated mica; and pearlescent (pearl) pigments made of foil powder, such as basic lead carbonate. These are added and dispersed in the base sheet as powder or scale-like foil pieces.

(Others) In addition, various additives are appropriately added to the base sheet as needed. Additives, for example,
Fillers such as inorganic powders such as calcium carbonate and clay; flame retardants such as magnesium hydroxide; antioxidants; foaming agents; lubricants; ultraviolet absorbers;

Further, the base sheet may be optionally provided with
On one or both sides, corona discharge treatment, plasma treatment,
An easy adhesion treatment such as an ozone treatment and formation of an easy adhesion layer may be performed.

[Surface Sheet] The surface sheet 2 is a transparent sheet made of a specific polyolefin resin. The specific polyolefin-based resin is an olefin-based thermoplastic elastomer comprising a mixture of a crystalline polyolefin resin and a styrene-based thermoplastic elastomer as a soft segment. Further, the topsheet has a transparency that allows the color tone of the underlying base sheet and the decorative layer and the like to be seen through. The transparency may be colored and transparent.

The above-mentioned crystalline polyolefin resin includes:
A crystalline polyolefin polymer such as polyethylene (high density, medium density or low density), polypropylene, polybutene, and ethylene-propylene-butene copolymer is used.

Examples of the styrene thermoplastic elastomer include HSBR (hydrogenated styrene-butadiene rubber), SEBS (styrene-ethylene-butylene-styrene block copolymer), SEPS (styrene-ethylene-propylene-styrene block copolymer), SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene block copolymer), or SEBC (styrene-ethylene-butylene-block copolymer having a crystalline polyethylene portion) is used.

The styrene-based thermoplastic elastomer is preferably mixed with the crystalline polyolefin resin in an amount of, for example, 5 to 30 parts by weight of the styrene-based thermoplastic elastomer per 100 parts by weight of the crystalline polyolefin resin. If the amount is less than 5 parts by weight, the scratch resistance becomes insufficient. If the amount is more than 30 parts by weight, the topsheet becomes too flexible, so that printing, lamination of the topsheet on the base sheet, and decorative sheet can be performed. When processing such as laminating to other sheets or adherends, the sheets are easily deformed and difficult to process, and when the decorative sheet is adhered to the adherend and used for various purposes, the decorative sheet When a steady stress is applied to the sheet, creep deformation occurs, and the decorative sheet is turned up.

The specific polyolefin-based resin as described above can be formed into a surface sheet by a film forming method such as a calendering method, an inflation method, and a T-die extrusion method. The top sheet may be laminated on the base sheet at the same time as the formation of the sheet by a T-die extrusion method. The reverse is also possible. The thickness of the topsheet depends on the application and the like, but is about 20 to 300 µm, usually about 50 to 100 µm. As the surface sheet, any of a stretched sheet and an unstretched sheet can be used, but the unstretched sheet has better suitability for forming such as V-cut processing (bending workability).

Further, the surface sheet, like the base sheet,
Fillers, flame retardants, antioxidants, lubricants, as needed
Various additives such as an ultraviolet absorber and a light stabilizer are added. In particular, since the topsheet is on the front side, one or both of a UV absorber such as a benzotriazole type and a light stabilizer such as a hindered amine-type ragacil scavenger may be used for applications requiring improved weather (light) resistance. It is preferable to add as an agent to improve weather (light) resistance. The amount of addition is usually in the range of 0.1 to 5% by weight. These weathering agents can of course be used for the base sheet.

Among the above-mentioned additives, an ultraviolet absorber having a hydroxyl group is used as the ultraviolet absorber, and an ultraviolet absorber bleed blocking layer described later is provided on the surface sheet, so that the ultraviolet absorber can be used. This effectively prevents the ultraviolet absorption performance from being lowered due to bleed-out, and provides excellent weather resistance.

As the ultraviolet absorber having a hydroxyl group, an organic compound having a hydroxyl group in a molecule can be used. For example, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-tert-
Butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-tert
-Amyl-5'-isobutylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-isobutyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy- 2'-hydroxyphenyl-5-chlorobenzotriazole ultraviolet absorbers such as 3'-isobutyl-5'-propylphenyl) -5-chlorobenzotriazole, 2- (2'-
Hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-
2 'such as 5'-methylphenyl) benzotriazole
Benzotriazole-based ultraviolet absorbers, such as hydroxyphenylbenzotriazole-based ultraviolet absorbers, 2,
2'-dihydroxy-4-methoxybenzophenone,
2,2'-dihydroxybenzophenone-based ultraviolet absorbers, such as 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2-hydroxy-4- 2-hydroxybenzophenone UV absorbers such as methoxybenzophenone and 2,4-dihydroxybenzophenone; benzophenone UV absorbers such as phenyl salicylate and 4-tert-butyl-phenyl-salicylate; Used. In addition, a reactive ultraviolet absorber in which an acryloyl group or a methacryloyl group is introduced into a benzotriazole skeleton is also used. The amount of these ultraviolet absorbers is usually about 0.1 to 10% by weight based on the resin content.

The top sheet is also provided with a corona discharge treatment, if necessary, especially on the back side of the base sheet.
An easy adhesion treatment such as a plasma treatment, an ozone treatment, and formation of an easy adhesion layer may be performed.

[Lamination of base sheet and surface sheet] As a method of laminating the base sheet and the top sheet, the lamination is performed simultaneously with the film formation by melt extrusion coating (extrusion coating) and the fusion by hot press. Alternatively, a known lamination method such as dry lamination using an adhesive such as a two-component curing type polyurethane resin or polyester resin may be used.

[Adhesive Layer] An adhesive layer for adhering the decorative sheet to the adherend may be provided on the back surface of the decorative sheet, if necessary. The adhesive layer depends on the application,
A conventionally known adhesive such as a thermoplastic resin or a curable resin by thermosetting may be used.

[Decoration treatment] The use of a base sheet as a colored sheet is already a kind of decoration treatment, and the use of a transparent sheet as a top sheet can also impart a feeling of painting.
This is also a kind of decoration processing. The decorative sheet of the present invention may have been subjected to various conventionally known decorative treatments other than these. Various decoration treatments may be used in combination as appropriate depending on the application.

The decorative treatment is, for example, a treatment for making a transparent topsheet colored and transparent. This is a treatment in which a coloring agent such as a pigment or a dye is added to the resin of the topsheet. You can do it. Further, as shown in FIG. 1B, the provision of a decorative layer 3 for expressing a pattern by printing or the like, embossing (heating press) as shown in FIG. 1C.
Alternatively, shaping of the uneven pattern 4 by hairline processing or the like may be used.

(Decoration Layer) The decoration layer is formed by ink (or paint) using a known printing method (or coating method) such as gravure printing, offset printing, silk screen printing, and transfer printing from a transfer sheet. . Examples of the pattern of the decorative layer include a wood grain pattern, a stone grain pattern, a cloth grain pattern, a leather pattern, a geometric figure, a character, a symbol, and a solid surface. The decorative layer is provided between the base sheet and the top sheet (see FIG. 1B), on the back side of the base sheet, on the front side of the top sheet, and the like. When the decorative layer is between the base sheet and the top sheet,
In the formation of the decorative layer by printing or the like, after forming the decorative layer on the base sheet side or the top sheet side, both sheets are laminated.

As the ink (or paint), chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polyesters, urethane resins, acrylic resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymers, and cellulose-based binders can be used. One or a mixture of two or more resins is used. A material obtained by adding a known coloring agent such as a pigment to the above is used.

In the case of printing directly on a base sheet or a top sheet, chlorinated polyolefin, urethane resin or the like is preferred as a binder in terms of adhesiveness, but a known easy adhesion treatment may be performed on the printed surface. The easy-adhesion treatment is, for example, a Rona discharge treatment, a plasma treatment, or the formation of an easy-adhesion layer by coating or printing.

The decorative 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 Concavo-convex Pattern) The concavo-convex pattern 4 is formed by embossing or the like. As the embossing process, the surface sheet before lamination, or the laminated sheet after laminating the base sheet and the surface sheet, etc. is heated and softened, pressed with an embossing plate, shaped, cooled and fixed, and formed. A known single-wafer or rotary embossing machine is used. As the uneven pattern, wood grain board conduit groove, stone board surface unevenness (granite cleavage plane etc.),
Fabric surface texture, satin finish, grain, hairline, line and groove, etc. Further, if necessary, a colored portion can be formed by filling a concave portion of the concavo-convex pattern 4 with a coloring ink by a known wiping method (see Japanese Patent Publication No. 58-14312 or the like). The coloring ink can be the same as the decorative layer. However, from the viewpoint of abrasion resistance, a material using a two-component curable urethane resin as a binder is preferable. The uneven pattern is usually on the front side, but may be on the interlayer or the back side.

(Other Decoration Processing) The decoration processing includes formation of an overcoat layer for the purpose of adjusting the gloss and imparting a design property such as a feeling of painting. The following ultraviolet absorbent bleed blocking layer can be provided as an overcoat layer. That is, in addition to the layer that blocks the bleed-out of the ultraviolet absorber, it can also be used as a layer having a matt surface, a glossy adjustment, a design property such as a painted feeling, or other functions.

[Ultraviolet absorbent bleed blocking layer] When an ultraviolet absorbent is contained in the topsheet, it is preferable to provide an ultraviolet absorbent bleed blocking layer on the topsheet. By UV absorber bleed blocking layer,
This prevents the ultraviolet absorber from bleeding out to the surface of the decorative sheet to reduce the ultraviolet absorption effect and the weather resistance. As the resin constituting the ultraviolet absorbent bleed blocking layer, an epoxy resin can be expected to have a certain effect, but more preferably, a urethane resin such as a two-part curable urethane resin or a one-part curable urethane resin is used. . More preferably, a combination of using the above-mentioned ultraviolet absorber having a hydroxyl group in the molecule as the ultraviolet absorber and using a resin having an isocyanate group for the ultraviolet absorber bleed blocking layer is preferable. It is preferable to use a urethane resin such as the above two-component curable urethane resin and one-component curable urethane resin. In this case, it is preferable that isocyanate groups remain when these urethane resins are converted into resins by urethane reaction. In addition, the thickness of the ultraviolet absorbent bleed blocking layer is set to 0.5 to 100 μm, usually about 1 to 10 μm.

For example, a two-component curable urethane resin has a polyol as a main component and an isocyanate as a crosslinking agent (curing agent).
Urethane resin. The polyol has two or more hydroxyl groups in the molecule, and examples thereof include polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol. As the isocyanate, a polyisocyanate having two or more isocyanate groups in a molecule is used. For example, 2,4-tolylene diisocyanate,
Aromatic isocyanates such as xylene diisocyanate and 4,4'-diphenylmethane diisocyanate; aliphatic (or alicyclic) isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate; Adducts or multimers of various isocyanates can also be used. For example,
There are an adduct of tolylene diisocyanate and a trimer of tolylene diisocyanate.

As a preferred embodiment in the case of a two-part curable urethane resin, the number (molar number) of isocyanate groups (—NCO groups) in the isocyanate and the number of hydroxyl groups (—OH groups) of the polyol to be reacted therewith (reaction equivalent weight) In some embodiments, the number of unreacted isocyanate groups is ensured even after the polyol and the isocyanate have reacted, and a large number of them remain. In this case, the ratio of -NCO group / -OH group is up to about 1.4 at the maximum.

The method of forming the bleed-blocking layer for the ultraviolet absorbent is not particularly limited.
It may be formed by a coating method such as a conventionally known gravure coat or roll coat. In addition, usually, it is formed after laminating the base sheet and the top sheet, but before laminating these sheets,
It may be formed on a topsheet.

[Applied Body of Decorative Sheet] The application of the decorative sheet of the present invention is not particularly limited, and the decorative sheet is laminated on the surface of various adherends and used for decorative application of the surface. The adherend is a plate material such as a flat plate or a curved plate of various materials, a three-dimensional article, a sheet (or film), or 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. Material, acrylic resin, polyester resin, polystyrene resin, polyolefin resin such as polypropylene,
ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenolic resin, vinyl chloride resin, cellulosic resin, rubber or other plate material, resin material used as a three-dimensional article or sheet, or high quality paper used exclusively as a sheet , 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 adherend] As a method of laminating a decorative sheet on these various adherends, for example, pressure is applied to a plate-like substrate with a pressure roller via an adhesive. As described in Japanese Patent Publication No. 50-19132, Japanese Patent Publication No. 43-27488, etc., after the decorative sheet is placed between the male and female molds for injection molding, the molten resin is placed in the mold. A so-called simultaneous injection molding lamination method in which injection molding is performed and a decorative sheet is adhered and laminated on the surface of the resin molded article simultaneously with the molding thereof, as described in JP-B-56-45768 and JP-B-60-58014. , A decorative sheet is opposed to or placed on the surface of a three-dimensional article such as a molded article with an adhesive therebetween, and the decorative sheet is laminated 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 Laminating method, as described in JP-B-61-5895, JP-B-3-2666, etc., an adhesive is provided between a decorative sheet and a columnar substrate such as a column or a polygonal column in the long axis direction. While feeding through
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 a plurality of rollers having different directions.

Further, 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, a V-cut or U-cut processing method among the above-mentioned methods is preferable. Since the decorative sheet of the present invention has improved bending workability, the laminating method in which these decorative sheets are bent is suitable.

[Use of decorative sheet and laminate thereof] The decorative sheet of the present invention is laminated on various adherends, subjected to predetermined molding processing as required, and used for various purposes. For example,
Interior decoration of buildings such as walls, ceilings, floors, surface decoration of fittings such as window frames, doors, handrails, surface decoration of furniture or cabinets of light electric / OA equipment, vehicle interiors such as automobiles, trains, aircraft, ships, etc.
Window glass makeup.

[0053]

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

Example 1 As a colored base sheet, a 100 μm-thick sheet was formed by a calender method using a high-density polyethylene resin having the following composition.

100 parts by weight of high-density polyethylene blended with resin of base sheet (J-LEX HDE707, manufactured by Japan Polyolefin Co., Ltd.) 1 part by weight of stabilizer 6 parts by weight Color pigment (composed of titanium white, red iron oxide, and graphite) (Calcium carbonate powder) 15 parts by weight Lubricant 0.5 parts by weight Weathering agent (hindered amine radical scavenger) 2 parts by weight Styrene-based thermoplastic elastomer (SEBC) 15 parts by weight (JSR Corporation, JSR 4600P)

After subjecting one surface of the base sheet to corona discharge treatment, a wood grain decorative layer was formed by gravure printing with a coloring ink using a resin mixture of a urethane resin and an acrylic resin as a binder resin. . Then, after applying a two-component curable urethane resin-based adhesive composed of polyester polyol and isocyanate as an easy-adhesion layer to the printed surface, a polypropylene-based thermoplastic elastomer having the following composition is used as a non-colored transparent surface sheet. Was melt-extruded and laminated at the same time as film formation to form a laminated sheet. The thickness of the laminated topsheet was 100 μm. On this occasion,
The cooling roller was also used as an embossing plate, and the unevenness of the surface of the roller was used to form a grain pattern of a wood grain conduit on the surface of the decorative sheet simultaneously with the formation of the sheet.

100 parts by weight of resin-containing polypropylene for the surface sheet (Nobrene S131 manufactured by Sumitomo Chemical Co., Ltd.) 1 part by weight of stabilizer Stabilizer ・ Benzotriazole type ultraviolet absorber having a hydroxyl group in the molecule (manufactured by Asahi Denka Kogyo Co., Ltd.) , LA-36) 8000 ppm-Hindered amine radical scavenger 4000 ppm Lubricant 0.5 part by weight Styrene-based thermoplastic elastomer (HSBR) 15 parts by weight (JSR 1320P, manufactured by JSR Corporation)

Then, a decorative sheet as shown in FIG. 2 was obtained. If the decorative sheet S of FIG. 2 is explained, the colored base sheet 1
The decorative layer 3 is printed thereon, and the transparent topsheet 2 is laminated thereon, and the uneven pattern 4 is formed on the surface of the topsheet 2. The performance evaluation is shown in Table 1 below.

Embodiment 2 A decorative sheet S as shown in FIG.
Acrylic polyol 1 was applied to the surface of the decorative sheet of Example 1.
A two-part curable urethane resin consisting of 00 parts by weight and 10 parts by weight of hexamethylene diisocyanate is applied by roll coating, and after forming the concavo-convex pattern 4, the ultraviolet absorbent bleed blocking layer 5 also serving as a top coat layer for surface protection is formed. It was formed to a thickness of 5 μm. The rest is the same as the first embodiment. The performance evaluation is shown in Table 1 below.

[Comparative Example] In the same manner as in Example 1, except that a resin not containing only a styrene-based thermoplastic elastomer was used as the resin for the topsheet.
A decorative sheet was produced.

[Evaluation of Performance] The bending strength and abrasion resistance of each of the decorative sheets of the above Examples and Comparative Examples were evaluated as follows. The evaluation results are shown in Table 1.

Bending strength: As an index of bending workability,
The evaluation was made by a bending test method according to JIS K 6744. The bending direction was such that the substrate sheet side was inside. The difference between the bendability tests 1 and 2 is the difference between the test temperature of 25 ° C. ± 5 ° C. and 0 ° C. ± 1 ° C. (low-temperature workability test). The evaluation was evaluated as good (○) when cracking, whitening and peeling did not occur, slightly good (△) when slightly whitening occurred, and poor (x) when cracking and peeling occurred.

Scratch resistance: A fingernail was set up and the front side of the decorative sheet was rubbed. In the evaluation, those that did not leave behind the nails were visually evaluated as good (○), those that remained but were not noticeable were slightly good (△), and those that remained were poor (x).

Weather resistance: Using a carbon arc lamp type Sun Shan Iwezaometer, a black panel temperature of 63 ° C.
Each decorative sheet was exposed for 1000 hours under conditions of rainfall time of 18 minutes during 120 minutes, the degree of whitening of the surface due to bleed-out of the ultraviolet absorber, and a tensile test between the base sheet and the top sheet in a 25 ° C. atmosphere. The layers were peeled off by a machine, and the peel strength between the layers was measured.

[0065]

[Table 1]

As shown in Table 1, in Examples 1 and 2,
Since the surface sheet was made of a specific polyolefin resin containing a styrene-based thermoplastic elastomer, both bending workability and scratch resistance were satisfactory and both were good. However, in the comparative example in which the styrene-based thermoplastic elastomer was not contained in the topsheet, the suitability for bending and the scratch resistance were not compatible. Further, in the decorative sheet of Example 2 in which an ultraviolet absorbent bleed blocking layer was further provided on the top sheet in addition to the ultraviolet absorbent having a hydroxyl group, the weather resistance was improved as compared with Example 1 and the comparative example.

[0067]

According to the decorative sheet of the present invention, the polyolefin resin of the topsheet is made of an olefin thermoplastic elastomer comprising a mixture of a crystalline polyolefin resin and a styrene thermoplastic elastomer. Bending workability necessary for working and the like and surface strength such as scratch resistance can be compatible. Further, when an ultraviolet absorber having a hydroxyl group is contained in the topsheet and a bleed blocking layer for the ultraviolet absorber is provided on the topsheet, weather resistance is improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating some embodiments of a decorative sheet according to the present invention.

FIG. 2 is a cross-sectional view illustrating another embodiment of the decorative sheet of the present invention.

FIG. 3 is a cross-sectional view illustrating another embodiment of the decorative sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base sheet 2 Top sheet 3 Decorative layer 4 Concavo-convex pattern 5 UV absorber bleed blocking layer S Decorative sheet

Continued on the front page F term (reference) 4F100 AK03A AK03B AK05 AK07 AK12B AL05B AL09B AR00C BA02 BA03 BA10A BA10C CA07B GB07 GB33 GB81 HB00A JA11B JB16B JD05C JK04 JK14 JL00 JL01 JL09 JL10A JN01

Claims (2)

[Claims] 1. A transparent base sheet made of a polyolefin resin is laminated on the surface of a colored base sheet made of a polyolefin resin, and at least the surface sheet is made of a crystalline polyolefin resin and a styrene thermoplastic resin. A decorative sheet, which is an olefin-based thermoplastic elastomer comprising a mixture with an elastomer. 2. A decorative sheet comprising a surface sheet containing an ultraviolet absorber having a hydroxyl group, and an ultraviolet absorber bleed blocking layer formed on the surface sheet.