JPH11207889A - Manufacture of decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the simple and low cost manufacturing method of a decorative sheet, which is excellent in interlaminar bondability and tender to environment. SOLUTION: In the manufacturing method of a decorative sheet, which is formed through an adhesive layer 14 by laminating an olefin-based resin or thermoplastic elastomer or either on selected from a group consisting of an olefin-based thermoplastic elastomer obtained by blending an isotactic polypropylene (or a hard segment) with an atactic polypropylene (or a soft segment), a matter obtained by graft-polymerizing the blend of the isotactic polypropylene (or the hard segment) and the atactic polypropylene (or the soft segment) on a compound having a polar functional group and an ethylene- propylene-butene copolymer on a base material sheet 19 made of high density polyethylene, rubber and inorganic filler or the ethylene-propylene-butene copolymer, an ozone blasting treatment is applied on the surface of the olefin-based resin before the above-mentioned laminating process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to construction materials such as furniture and fittings, automobiles and vehicles, wherein an ozone treatment is applied to the surface of a topsheet made of an olefin resin and a base sheet is attached. The present invention relates to a method for producing a decorative sheet useful for a surface decoration material of an aircraft or the like.

[0002]

2. Description of the Related Art Conventionally, decorative sheets for building materials using a vinyl chloride resin have been known. However, since the decorative sheet using the vinyl chloride-based resin uses the vinyl chloride resin as a material, toxic chlorinated substances are generated at the time of disposal and combustion, and thus there is a problem of environmental pollution. For this reason,
A decorative sheet using an olefin resin which is a non-vinyl chloride resin has been proposed.

[0003] Although such olefin-based resins are excellent in environmental aspects, they have poor adhesiveness. Therefore, decorative sheets produced by laminating olefin-based resins have manufacturing problems, and various devices have been devised so far.

[0004] For example, a method in which an olefin resin is melt-extruded and laminated on the surface of a base sheet (so-called extrusion coating method), a method in which a base sheet and a previously formed olefin resin surface sheet are bonded with a normal adhesive There is known a method of bonding using a so-called "dry lamination method", and a method of performing a corona discharge treatment on a surface sheet in advance in order to further improve the adhesive force by the dry lamination method.

As a method of coating a polyolefin resin surface sheet such as a polypropylene layer on a base sheet of a decorative sheet by melt extrusion (that is, a method of sticking a flat sheet to each other), for example, a polypropylene sheet is melt-extruded. Immediately after melt-extruding a two-layer film composed of a layer and a polyethylene layer containing an ethylene-α-olefin copolymer, at least the surface portion of the two-layer film is an ethylene-α-olefin copolymer in a molten state. A method for producing a laminate is also known in which a gas containing ozone is blown at a constant rate to the surface of a polyethylene layer containing the compound to perform ozone treatment, and then the two-layer film is bonded to another base material sheet. (See Japanese Patent Publication No. 62-60970).

[0006]

However, in the method of laminating a topsheet by melt-extrusion of the above-mentioned olefin resin, the olefin resin has poor adhesion and interlayer adhesion is insufficient. In addition, adhesion by dry lamination through an ordinary adhesive is poor.

[0007] In the dry laminating method after the corona discharge treatment, a step of subjecting the surface sheet to a corona discharge treatment and a step of dry-laminating the corona-treated surface sheet and the base sheet are performed. And a separate line, the manufacturing apparatus becomes large, and there is a problem in manufacturing cost.

[0008] Further, the decorative sheet produced by any of the methods is uneven and insufficient elongation (so-called necking) when the decorative sheet is bent, so that stress is locally concentrated on the bent portion and whitening or the like occurs. There was a problem that cracks were easily formed. This is due to the material dynamics of the conventional olefin resin. Therefore, an object of the present invention is to provide a method for easily and inexpensively manufacturing a decorative sheet having excellent interlayer adhesion and being environmentally friendly.

[0009]

Means for Solving the Problems In order to solve the above problems,
The present invention relates to a method for producing a decorative sheet having a step of laminating a base sheet and a surface sheet made of an olefin resin through an adhesive layer, wherein an adhesive is provided between the base sheet and the olefin resin. A method for producing a decorative sheet, comprising performing ozone spraying on a surface of a side to be bonded to a base sheet of the olefin-based resin before a step of laminating through a layer.

In the method for producing a decorative sheet according to the present invention,
The base sheet is preferably made of a composition obtained by adding rubber and an inorganic filler to high-density polyethylene or polypropylene, or an ethylene-propylene-butene copolymer.

In the method for producing a decorative sheet according to the present invention, the olefin-based resin may be an olefin-based thermoplastic elastomer comprising a blend of an isotactic polypropylene (hard segment) and an atactic polypropylene (soft segment). For blends of tic polypropylene (hard segment) and attack tic polypropylene (soft segment),
Further, a thermoplastic elastomer of a compound obtained by graft-polymerizing a compound having a polar functional group or an ethylene-propylene-butene copolymer is preferable.

Hereinafter, the present invention will be described in detail. The base sheet used in the decorative sheet manufacturing method of the present invention has a configuration in which a decorative treatment is applied to a thermoplastic resin sheet. Examples of the thermoplastic resin include an olefin resin, an acrylic resin, a polyester resin, a fluororesin, a polystyrene resin, and a polycarbonate resin. A single layer or a laminate of two or more layers may be used. Can be.

The olefin resin used for the base sheet of the decorative sheet includes, for example, an olefin thermoplastic elastomer and a non-elastramer olefin resin. Specifically, polyethylene, polypropylene, polymethylpentene, ethylene-propylene copolymer, ethylene-propylene-butene copolymer, crystalline non-elastomeric olefin resin such as ionomer,
Alternatively, an olefin-based thermoplastic elastomer is used, but an olefin-based thermoplastic elastomer is preferable from the viewpoint of suitability for forming a decorative sheet.

[0014] The olefin-based thermoplastic elastomer resin is a thermoplastic elastomer elastomer of a composite material comprising an olefin-based elastomer and a non-elastomeric olefin-based resin. That is, (1) a simple blend of an amorphous olefin-based elastomer as a soft segment and a crystalline non-elastomeric olefin resin as a hard segment. (2) an olefin-based elastomer and a non-elastomeric olefin-based resin. (3) a type in which an olefin-based elastomer is crosslinked and dispersed in a non-elastomeric olefin resin.

Examples of the olefin-based elastomer include ethylene rubbers typified by EPDM, and examples of the non-elastomeric olefin-based resin include crystalline polymers such as polyethylene and polypropylene. In addition, additives such as a flame retardant and an antioxidant, which are used in ordinary olefin-based resins, can be appropriately added to the composition, if necessary. When these are used for the base sheet, pigments, extenders and the like can be added as appropriate.

As the type (2), for example,
B) JP-B-53-21021, JP-B-53-34
No. 210, etc., b) Japanese Patent Publication No. 56
And those described in US Pat.

More specifically, for example, the above-mentioned (a) includes 60 to 80 parts by weight of a monoolefin copolymerized elastomer (A), 40 to 20 parts by weight of a non-elastomeric polyolefin-based plastic (B), And those curing agents which are mixed and partially cured at the curing temperature to such an extent that they do not become insoluble in the usual solvents of the uncured blend during mastication. Examples of the olefin-based copolymer elastomer include an elastic copolymer obtained by adding at least one polyene copolymerizable with two or more olefins.

As the olefin, ethylene, propylene, α-olefin and the like are used, and as the polyene, 1,4-hexadiene, cyclic diene, norbonene and the like are used. Preferred olefin copolymer rubbers include, for example, elastic copolymers containing an olefin as a main component such as ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene rubber, and ethylene-propylene-butadiene copolymer rubber. No.

The non-elastomeric olefin plastic (B) is a crystalline thermoplastic resin obtained by polymerizing olefins such as ethylene, propylene, butene-1, pentene-1, and 4-methylpentene in a conventional manner. Yes, including polyethylene and polypropylene modified with higher α-olefins.

As the curing agent, peroxide,
Azide type, aldehyde-amine reaction products, substituted ureas, xanthates, dithiocarbamates, imidazoles, sulfonamides, thiuram disulfites, paraquinone dioxime, dibenzoparaquinone dioxime, sulfur and the like. it can.

The above composition is masticated on an open roll or heated to 150 ° C. in an internal mixer such as a Banbury mixer, an extrusion mixer or a transfer mixer.
Partial crosslinking can be performed by masticating at 280 ° C for 1-20 minutes.

The above-mentioned b) includes olefin copolymer rubbers such as ethylene / propylene copolymer rubber, ethylene / propylene non-conjugated diene rubber, ethylene / butadiene copolymer rubber, and propylene / ethylene copolymer; Propylene-1-copolymer, propylene / 1-hexene copolymer, propylene / 4-methyl-1-pentene copolymer, etc. are converted to high-boiling petroleum fractions, paraffins, naphthenes, aromatics, etc. And a mineral oil-based softening agent together with an organic peroxide to obtain a partially crosslinked olefinic thermoplastic elastomer by melt-kneading.
These can be produced in the same manner as in the above method a).

The olefin resin used in the base sheet of the present invention can be used alone. In particular, in the case of a crystalline non-elastomeric olefin resin, the olefin resin has a high elongation and a high flexibility. Imparts resistance, impact resistance, and easy adhesion, prevents sudden softening and fluidization near a specific temperature (melting point) during heating and heating, and increases the temperature at which molding can be performed. In order to eliminate so-called necking that causes uneven elongation, various rubbers can be preferably added.

The rubbers to be added include diene rubbers,
There are a hydrogenated diene rubber, an olefin elastomer and the like, and among them, a hydrogenated diene rubber is preferable.
The hydrogenated diene rubber is obtained by adding a hydrogen atom to at least a part of the double bond of the diene rubber molecule. In the present invention, crystallization of the olefin resin is suppressed, and flexibility and transparency are improved. Has a role. Also,
Generally, when a diene rubber is added to an olefin resin, due to the double bond of the diene rubber, the weather resistance and heat resistance are lower than those of the polyolefin resin without the diene rubber.
In the present invention, since the double bond of the diene rubber is saturated with hydrogen, the olefin resin has good weather resistance and heat resistance without deterioration.

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

The amount of rubber added is 100
It is preferably about 10 to 60 parts by weight based on parts by weight. 10
If the amount is less than the weight part, the effect of improving the elasticity, elongation rate, impact resistance, and the like by adding rubber is insufficient, and necking, cracks, and cracks are likely to occur during bending such as V-cutting and drawing. If the amount is more than 60 parts by weight, creep deformation tends to occur (decrease in creep resistance), and when a static force is applied to the decorative sheet for a long time, the sheet is turned up or permanent deformation remains. This results in poor weather resistance, or excessively high elasticity and elongation, resulting in poor registration of printing or the like.

Further, if necessary, other fillers, foaming agents, flame retardants, ultraviolet absorbers and the like can be added to the olefin resin. Inorganic fillers are added to decorative sheets for the purpose of improving physical properties such as creep resistance, easy adhesion, and appearance, such as barium sulfate, carbon black, calcium carbonate, calcium silicate, titanium white, and white. Examples include carbon, alumina, asbestos, mica, quartz powder, slate powder, silica, clay, and talc.

The average particle size of the inorganic filler is usually from 0.1 to
It is about 10 μm, and the added amount is 5 to 60% by weight. When the amount is less than 5% by weight, the improvement hardening such as creep deformation resistance and easy adhesion is insufficient.
Elongation at break and impact resistance decrease.

The foaming agent is added when the base material of the decorative sheet is made porous, and examples thereof include an azonitrile compound, a benzenesulfohydrazine compound and a diazoamide compound.

The flame retardant is added to impart flame resistance to the plastics material. Examples thereof include paraffin chloride, tricresyl phosphate, chlorinated oil, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, Examples include tetrabromobisphenol A, dibromopropyl phosphate, tri (2,3-dibromopropyl) phosphate, antimony oxide, hydrated alumina, and barium borate. The ultraviolet absorber is added to suppress oxidative decomposition of plastics, and examples thereof include alkylphenols, amines, and quinones.

The thermoplastic polyester resin contains aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid as acid components, and aliphatic diols such as ethylene glycol, diethylene glycol, butanediol and hexanediol as alcohol components. Is a copolymer which can be obtained as both esters. As a thermoplastic polyester resin, for example, polyethylene terephthalate, polybutylene terephthalate,
Ethylene terephthalate / isophthalate copolymer and the like can be mentioned.

Examples of the fluororesin include polyvinyl fluoride, polyvinylidene fluoride, ethylene tetrafluoroethylene copolymer and the like.

Examples of the polystyrene resin include polystyrene, acrylic styrene, and ABS.

Polycarbonate has —O—R— in its main chain.
It is a linear polymer having O-CO- and can be produced by, for example, reacting glycol with a dihydric phenol and phosgene, or reacting with a carbonate ester.
Bisphenol A and the like can be mentioned.

Among the above, as the base sheet material, (1) high density polyethylene having a specific gravity of 0.94 to 0.97 is used as a base polymer;
(2) Polypropylene, more preferably isotactic polypropylene as a base polymer, to which rubber and an inorganic filler such as calcium carbonate are added. And (3) an ethylene / propylene / butene random copolymer can be particularly preferably used.

The base sheet is subjected to a decoration treatment as desired. The decoration treatment includes, for example, a method of coloring the base sheet itself by adding a pigment, and a method of printing a pattern such as a picture on the base sheet with ink, paint, or the like.

Examples of the pigments to be added include inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine, cobalt blue, titanium yellow, carbon black, isoindolinone, Hansa Yellow A, quinacridone, and permanent red 4.
R, phthalocyanine blue, indaslen blue RS,
Organic pigments (including dyes) such as annin phosphorus black, metal pigments composed of foil powder such as aluminum and brass, pearlescent pigments composed of foil powders such as titanium dioxide-coated mica and basic lead carbonate, and the like. is there. The coloring by adding the pigment may be transparent coloring or opaque (concealing) coloring. These are added and dispersed as powder or scaly foil pieces.

As the pattern printing, a pattern can be formed with ink (or paint) using a known printing method such as gravure printing, offset printing, silk screen printing, and transfer printing from a transfer sheet.

Examples of the pattern 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 pattern can be provided on the front surface, the back surface, and the front and back surfaces of the base sheet. However, when the base sheet is opaque, only the surface is used.

As the ink or paint, chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polyester resins, urethane resins, acrylic resins, vinyl chloride / vinyl acetate copolymers as binders,
Cellulose-based resins and the like can be used, and one or more of these may be used in combination. For this, those to which the above-listed pigments are added are used.

In the case of printing directly on an olefin resin, chlorinated polyolefin, urethane resin and the like are preferable as a binder in terms of adhesiveness. However, if a layer is formed by appropriately selecting an easy-adhesion primer, other binders may be used. However, sufficient adhesiveness can be imparted even by using.

The olefin resin used as the surface sheet in the method for producing a decorative sheet of the present invention includes:
Polyethylene, ethylene / propylene copolymer, ethylene / butene-1 copolymer, polypropylene, propylene / butene-1 copolymer, polybutene-2, butene-1 ·
Non-elastomeric olefin resins such as propylene / ethylene / terpolymer, butene-1 / hexene / octene-1 / terpolymer, and polymethylpentene, or isotactic resins described in JP-B-6-23278. Olefinic thermoplastic elastomer of polypropylene type having a hard segment of tic polypropylene and a soft segment of atactic polypropylene, JP-A-5-773
An olefin-based thermoplastic elastomer such as an ethylene-propylene-butene ternary copolymer-based olefin-based thermoplastic elastomer described in JP-A-71-71, JP-A-9-111055, or the like can be used. These resins can be used alone or
Species or more may be mixed.

Of these, embossing of a decorative sheet,
Thermoplastic elastomers are preferred from the viewpoint of moldability such as bending, interlayer adhesion, transparency, weather resistance and the like. Preferred examples are olefinic thermoplastic elastomers comprising a blend of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment), and blends of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment) Is further obtained by graft polymerization of a compound having a polar functional group, or ethylene.
A thermoplastic elastomer of a propylene / butene copolymer can be used.

Among them, those having good moldability, transparency and light resistance are described in Japanese Patent Publication No.
No. 23278. Further, among the experiments and evaluations conducted by the inventor of the present application, it has been found that the following is particularly optimal. That is, in this kind of polypropylene-based olefin-based thermoplastic elastomer, the weight ratio of the atactic polypropylene as a soft segment is set to 5% by weight or more to form a three-dimensional or uneven article. Non-uniform deformation of the sheet due to necking during processing, and cracking, whitening, distortion of a picture, etc. of the sheet due to stress concentration caused by the necking can be eliminated. 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 the atactic polypropylene is too large, the creep resistance is lowered, and the sheet itself is easily deformed. When the sheet is passed through a printing machine, the sheet is deformed and the picture is distorted. In the case of multicolor printing, defects such as misregistration are likely to occur. Also,
It is not preferable because it is easily broken during molding. The upper limit of the weight ratio of the atactic polypropylene is 50% by weight or less, more preferably 40% by weight or less, when the decorative layer is printed using a normal rotary printing machine such as rotary gravure printing.

The thickness of the layer of the olefinic thermoplastic elastomer is about 20 to 200 μm, and any of a stretched sheet and an unstretched sheet can be used. Is better.

In the decorative sheet produced by the production method of the present invention, the base sheet and the transparent olefin-based thermoplastic resin layer are used in order to improve the adhesion between the printed base sheet and the transparent olefin-based thermoplastic resin as the surface sheet. An adhesive layer is provided between them.

Examples of the resin which can be used as the adhesive include urethane resins, polyester resins, polyamide resins, vinyl acetate-acrylate resins, carboxyl group-containing acrylic resins, vinyl acetate-ethylene resins, and polyvinyl resins. Each resin such as ether can be used. Among them, adhesion to the base sheet, adhesion to the olefin resin whose surface is ozone-treated in a molten state (including weather resistance), and flexibility enough to follow the bending process of the decorative sheet, Considering the elongation,
Urethane resin adhesives are particularly preferred.

As the urethane-based resin adhesive, it is preferable to use a two-component curable urethane resin. For example, it is a urethane resin having a polyol as a main component and an isocyanate as a cross-linking agent (curing agent).

The polyol has two or more hydroxyl groups in the molecule, for example, polyethylene glycol, polypropylene glycol, acrylic polyol,
Polyester polyol, polyether polyol, polycarbonate polyol and the like are 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 hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate,
An aliphatic (or alicyclic) isocyanate such as hydrogenated diphenylmethane diisocyanate is used. Alternatively, adducts or multimers of the above various isocyanates can also be used. For example, there are an adduct of tolylene diisocyanate, a trimer of tolylene diisocyanate, and the like.

The adhesive layer or the olefin resin layer of the decorative sheet according to the production method of the present invention may contain an ultraviolet absorber. As the ultraviolet absorber, those which can absorb ultraviolet light in the 280 to 450 nm region which causes deterioration of polyolefin can be arbitrarily selected from known ones.

As the ultraviolet absorber, for example, benzophenone type, salicylate type, benzotriazole type,
An acrylonitrile-based ultraviolet absorber and the like can be mentioned. For example, an organic compound having an OH group in the molecule can be used, and 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'-methyl Phenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3'-isobutyl-5'-propylphenyl)-
2′-hydroxyphenyl-5-chlorobenzotriazole-based ultraviolet absorbers such as 5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-ter)
t-butylphenyl) benzotriazole, 2- (2 ′
Benzotriazole-based UV absorbers such as 2'-hydroxyphenylbenzotriazole-based UV absorbers such as -hydroxy-5'-methylphenyl) benzotriazole; and 2,2'-dihydroxy-4-methoxybenzophenone, 2,2 ' 2-hydroxybenzophenones such as -dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxy-4,4'-tetrahydroxybenzophenone ultraviolet absorbers, and 2,4-dihydroxybenzophenone Benzophenone UV absorbers such as UV absorbers, phenyl salicylate,
A salicylic acid ester based ultraviolet absorber such as -tert-butylphenyl salicylate is used.

In addition, a reactive ultraviolet absorber in which an acryloyl group or a methacryloyl group is introduced into a benzotriazole skeleton can be used. Among these, a benzotriazole-based ultraviolet absorber is particularly preferred in consideration of the problems of absorption wavelength and coloring property.

Further, in the decorative sheet according to the production method of the present invention, the olefin-based resin layer is provided with various kinds of materials for the purpose of imparting weather resistance, that is, preventing discoloration, cracking, whitening, and strength deterioration due to sunlight. An amine radical scavenger can also be added.

As the radical scavenger, bis-
(2,2,6,6-tetramethyl-4-piperidinyl)
Sebacate and others, for example, hindered amine radical scavengers such as compounds disclosed in Japanese Patent Publication No. 4-82625, piperidyl radical scavengers and the like are used.

When a light stabilizer comprising a hindered amine radical scavenger is added to the polyolefin, urethane is used not only in the olefin resin but also in the ink layer and the adhesive layer adjacent to the olefin resin sheet. Use of a resin containing no chlorine atom in the molecule, such as a resin, an olefin-based resin, or a polyamide resin, is advantageous in terms of improving weather resistance.

Further, in the present invention, a primer layer can be provided on the base sheet in order to improve the adhesion between the base sheet and the printing ink layer. The primer layer is usually provided to improve the adhesion between the base sheet and the pattern ink by reacting with a functional group present on the surface because the base sheet is subjected to a corona discharge treatment. .

It is preferable to use a two-component curable urethane resin as the primer layer. When hexamethylene diisocyanate (HMDI) is used as the isocyanate and acrylic polyol is used as the polyol, light resistance to the olefin-based resin base material sheet is good, so that it can be particularly preferably used.

In the decorative sheet according to the production method of the present invention, a solid ink layer is further formed on the primer layer in order to improve the adhesion between the substrate sheet and the pattern printing layer. Can be provided.

In the solid ink layer, opaque pigments such as titanium oxide and carbon can be added, and by increasing the content thereof, ultraviolet rays can be cut and deterioration of the lower layer can be prevented. .

When it is not particularly necessary to consider blocking the ultraviolet rays from the base sheet, the solid ink layer is colored with a transparent ink on the medium in order to adjust the base color and utilize the color of the sheet. May be applied. Further, when it is desired to decorate the sheet with a color having a large difference in color tone, the sheet can be colored with white ink.

The outermost surface of the decorative sheet according to the production method of the present invention is preferably embossed. Preferably, the embossed concave portion is subjected to a wiping process of filling with ink, and the surface thereof is covered with a two-component curable urethane resin.

The embossing is performed to impart a desired texture such as a wood surface to the decorative sheet. For example, in embossing, an olefin resin is heated and softened on a heating drum, and then 160 to 1 with an infrared radiation heater.
It is formed by heating to 80 ° C., pressurizing and shaping with an embossed plate provided with a desired pattern of concavities and convexities, and cooling and fixing. A known single-wafer or rotary embossing machine is used. As the concavo-convex pattern, a wood grain conduit groove, a grain of sand, a satin finish, a hairline, a cleaved surface irregularity of granite, or the like is used.

The wiping process refers to a process in which a colored ink is applied to the surface, and then the colored ink is filled only in the concave portions formed by embossing while scraping the surface with a doctor blade (see Japanese Patent Publication No. 58-14312, etc.). ). As the coloring ink, a two-component curable urethane resin which is generally excellent in abrasion resistance can be used. The wiping process is performed in order to enhance the commercial value by expressing the design closer to the actual grain, particularly by performing it on the grain conduit groove irregularities.

The last overprint (OP) is provided to cover the fragility of the decorative sheet surface and to improve the scratch resistance. As the resin used for the OP processing, for example, a two-component curable urethane-based resin can be used. The two-component curable urethane resin is a urethane resin containing polyol as a main component and isocyanate as a crosslinking agent (curing agent). As the polyol and the isocyanate, those described above may be used.

The method for producing a decorative sheet according to the present invention comprises the step of:
A method for producing a decorative sheet having a step of laminating via an adhesive layer formed on a base sheet, wherein after subjecting the surface of the olefin-based resin to ozone spray treatment, the base sheet and the olefin are treated. It is characterized in that it is laminated with a system resin via an adhesive layer.

For example, as shown in FIG. 1, on an olefin resin sheet 2 that has been melt-extruded from a T-die 9 and has not yet been solidified by cooling, a side on which the base sheet 4 is laminated on the olefin resin sheet is The ozone-containing gas is blown from the ozone generator 3, and the olefin resin sheet 2 and the base sheet having the surface coated with the adhesive 8 by a coating roll are laminated with a laminator to form a decorative sheet. Can be manufactured.

The present invention relates to an olefin resin having a temperature at which decomposition of the olefin resin does not occur, that is, immediately after extrusion at an extrusion temperature of 300 ° C. or less, preferably at least a surface of which is in a molten state. By blowing a gas containing ozone onto the sheet surface and oxidizing the substrate surface, the adhesiveness to a substrate sheet having an adhesive layer with an adhesive on another surface is improved.

The gas containing ozone that is sprayed on the surface of the olefin resin in a molten state can be obtained by supplying air or oxygen to a general ozone generator.
In the present invention, at least an ozone concentration of 10 mg / m
It is preferable to spray at a rate of ^{3 to} 180 mg / m ³ . When the ozone concentration of the gas blown to the surface of the olefin resin sheet is less than 10 mg / m ³ , the degree of oxidation of the surface of the olefin resin sheet in the gas blowing step is not sufficient, and the surface of the olefin resin sheet has an adhesive. , It is not possible to obtain a strong adhesive strength with another base sheet having an adhesive layer, and the object of the present invention cannot be achieved. On the other hand, the ozone concentration is 180 mg / m ³
When the temperature exceeds, the ozone spraying effect is saturated, and the temperature of the heated olefin resin sheet surface is undesirably cooled.

The decorative sheet according to the production method of the present invention can be laminated on another adherend. Lamination is performed when the decorative sheet itself can be bonded to the adherend (by heat fusion, etc.)
The adhesive layer can be omitted. If the decorative sheet itself does not adhere to the adherend, it can be laminated with an appropriate adhesive. The adherend is the final product, and in some cases a decorative sheet is laminated for surface cosmetics, and if necessary, to enhance the mechanical strength of the decorative sheet or to provide concealment, An adherend may be laminated.

The adherend may be a plate material of various materials, such as a flat plate or a curved plate, a three-dimensional article, or a sheet (or film). Wood material such as medium density fiberboard (MDF), metals such as iron and aluminum, acrylic resin, polycarbonate, ethylene / vinyl acetate copolymer, ethylene vinyl acetate copolymer, polyester, polystyrene, olefin resin, ABS resin, Phenolic resin, polyvinyl chloride, cellulosic resin, rubber and other resins, materials exclusively used as plate materials or three-dimensional articles include glass, ceramics such as ceramics, and ALC
Ceramic materials such as cement (foamed lightweight concrete), calcium silicate, gypsum, etc. Materials used exclusively as sheets (or films) include paper such as high-quality paper and Japanese paper, or carbon, asbestos, potassium titanate, There is a nonwoven fabric or a woven fabric made of fibers such as glass and synthetic resin.

As a method of laminating these various adherends,
For example, as described in Japanese Patent Publication No. 50-19132, Japanese Patent Publication No. 43-27488, etc., a decorative sheet is a method of laminating a plate-like substrate by pressing with a pressure roller via an adhesive. Into the injection-molded male and female molds,
After closing both molds and injecting and filling the molten resin from the male mold gate, cooling and molding the resin molded product, and simultaneously bonding and laminating a decorative sheet on the surface, the so-called simultaneous injection molding laminating method, No. 45768, Japanese Patent Publication No. Sho 6
As described in Japanese Patent Publication No. 0-58014, a decorative sheet is opposed to or placed on the surface of a molded article via an adhesive layer therebetween, and the decorative sheet is molded by a pressure difference caused by vacuum suction from the molded article. So-called vacuum press laminating method for laminating on the product surface, Japanese Patent Publication No. 61-5895, Japanese Patent Publication No. 3-26
No. 66, etc., in the long axis direction of a columnar substrate such as a cylinder, a polygonal column, etc., while supplying a decorative sheet through an adhesive layer therebetween, a plurality of rollers having different orientations are used. A so-called lapping method, in which a decorative sheet is sequentially adhered to a plurality of side surfaces constituting a body by pressure bonding and laminated, as described in Japanese Utility Model Publication No. 15-31122, JP-A-48-47972 and the like. First, the decorative sheet is laminated on the plate-like base material via the adhesive layer, and then reaches the interface of the decorative sheet and the plate-like base material on the surface of the plate-like base material opposite to the decorative sheet. A so-called V-cut or U-cut in which a groove having a V-shaped or U-shaped cross section is cut, and then an adhesive is applied in the groove, and then the groove is bent to form a box or a column. There are processing methods and the like.

The decorative sheet according to the production method of the present invention can be used for various applications by laminating on various adherends and subjecting it to a predetermined molding process. For example,
Interior decoration of buildings such as walls, ceilings and floors, surface decoration of fittings such as window frames, doors, handrails, furniture such as chests or cabinets such as television receivers, etc., surface decoration of cabinets such as OA equipment, There are vehicle interiors such as automobiles and trains, aircraft interiors, ship interiors, and window glass makeup.

[0075]

Next, a method for producing a decorative sheet according to the present invention will be described in more detail with reference to embodiments of the present invention. FIG. 1 shows an outline of a method for producing a decorative sheet of the present invention. In the figure, 1 is a decorative sheet produced by the production method of the present invention, and 2 is an olefin-based resin surface sheet before being cooled and solidified by melt extrusion molding from a T-die 9.

The olefin resin constituting the olefin resin sheet is an olefin thermoplastic elastomer comprising a blend of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment), and isotactic polypropylene (hard segment). ) And an attack polypropylene (soft segment) blended with a compound having a polar functional group by graft polymerization, or a thermoplastic elastomer of an ethylene-propylene-butene copolymer.

The side of the olefin resin sheet 2 to be bonded to the base sheet on the surface of the olefin resin sheet 2 generates ozone while the resin sheet immediately after being melt-extruded is still hot (about 160 to 200 ° C.). the device 3, the gas is supplied which contains ozone of ^{10mg / m 3 ~180mg / m 3} , an ozone treatment. 4 is
A base sheet made of high-density polyethylene or polypropylene as a base polymer to which rubber and an inorganic filler are added, or a base sheet made of an ethylene-propylene-butene copolymer. The base sheet 4 is fed from the base sheet take-up roll 7, and is coated on the surface of the base sheet 4 (the side to be bonded to the olefin-based resin layer) via the coating roll 20 via a two-component curable urethane. The resin adhesive 8 is applied. Then, the base sheet 4 and the olefin-based resin sheet 2 are laminated with a laminating roll (impression cylinder roll).
6 and chill roll 5 for laminating melted surface sheet 2
Is cooled and solidified, whereby the decorative sheet 1 is manufactured. The cooling roll 5 also serves as an embossing roll, and embossing is performed on the surface of the olefin-based resin sheet simultaneously with lamination.

The decorative sheet manufactured as described above is manufactured by subjecting an olefin-based resin sheet to an ozone treatment on an adhesive surface side with the base sheet and then bonding the olefin resin sheet to the base sheet. Therefore, it has excellent interlayer adhesion.

The olefin resin sheet manufactured according to the present embodiment includes an olefin thermoplastic elastomer comprising a blend of isotactic polypropylene (hard segment) and atactic polypropylene (soft segment), isotactic polypropylene. (Hard segment) and a blend of atactic polypropylene (soft segment) and a graft polymer of a compound having a polar functional group, or a thermoplastic elastomer of ethylene / propylene / butene copolymer I have.

Further, the base sheet is made of high-density polyethylene or polypropylene as a base polymer to which rubber and an inorganic filler are added, or ethylene / polypropylene.
Since it is made of a propylene / butene copolymer and the adhesive layer is made of a two-component curable urethane resin, it has particularly excellent interlayer adhesion between the base sheet and the topsheet, and also bends the decorative sheet. In this case, the elongation rate and impact resistance are excellent, and non-uniformity and insufficient elongation (so-called necking) do not occur, and no stress is locally concentrated on the bent portion to cause whitening or cracking.

[0081]

Example 1 Next, an example of the production of a decorative sheet according to the production method of the present invention will be described. First, styrene / 60 parts by weight of high density polyethylene
30 parts by weight of butadiene rubber, 10 parts by weight of an inorganic filler composed of particles of calcium carbonate having an average particle size of 2 μm, and 5 parts by weight of titanium white, carbon black, graphite and red iron oxide as coloring pigments are added. After applying corona discharge treatment to both the front and back surfaces of the colored polyethylene thermoplastic elastomer sheet 11 having a thickness of 0.1 mm, the thickness of the two-component curable urethane resin (composed of polyester polyol and tolylene diisocyanate) on the surface. 1 μm of the primer layer 12, the pigment is made of red iron oxide, graphite, carbon black,
A base sheet 19 in which a colored solid layer 13 and a grain pattern layer 15 of a colored ink whose binder is a polyurethane / acrylic block copolymer are sequentially provided by gravure printing.
Was prepared.

Next, a two-part curable urethane resin adhesive consisting of acrylic polyol and hexamethylene diisocyanate was applied on the surface of the base sheet 19 by a gravure reverse coating method in an amount of 15 g / m ² (dry).

Next, a polypropylene-based thermoplastic elastomer sheet 16 comprising 20 parts by weight of an atactic polypropylene soft segment and 80 parts by weight of an isotactic polypropylene hard segment was melt-extruded with a T-die. 180 ° C
Then, ozone treatment is performed by spraying a gas containing 0.02 g / m ³ of ozone onto the laminate surface, and the laminate is laminated as a layer having a thickness of 80 μm, and at the same time, the polypropylene-based thermoplastic elastomer sheet 16 is cooled by a cooling roll and an embossing roll. Embossing of wood channel groove 1 on the surface
7 was given.

A two-part curable urethane resin composed of acrylic polyol and hexamethylene diisocyanate was applied as a top coat (OP coat) layer 18 to the sheet obtained as described above at a thickness of 2 μm. Cured for 2 days. FIG. 2 shows a sectional view of the decorative sheet obtained as described above.

The decorative sheet obtained in Example 1 had an adhesion between the olefin resin sheet and the base sheet of 3 kg / kg.
inch, weather resistance test (carbon arc lamp type sunshine weatherometer, black panel temperature 63
Acceleration test under the conditions of ℃, rainfall time 18 minutes / 120 minutes)
Even after irradiation for 1,000 hours, the adhesive strength was 1.5 kg / inch.

The adhesion was evaluated by the tension when a tensile test was performed between the olefin resin sheet and the base sheet at a spread angle of 180 ° at a speed of 50 mm / min. The width of the test piece was 1 inch and the ambient temperature was 20 °.

[0087] Except that not subjected to ozone treatment to Comparative Example 1 laminate immediately before, to produce a decorative sheet of Comparative Example 1 in the same manner as in Example 1. The decorative sheet obtained in Comparative Example 1 had an adhesion of 1.8 kg / i.
nch, weather resistance test (same as in the examples) 1,000
After irradiation for an hour, the adhesive strength was 0.9 kg / inch, and it was found that the interlayer adhesive strength was clearly inferior to the decorative sheet obtained in Example 1.

[0088]

As described above, according to the method for manufacturing a decorative sheet of the present invention, a decorative sheet having excellent interlayer adhesion can be easily and inexpensively manufactured. In addition, the decorative sheet manufactured by the manufacturing method of the present invention mainly uses an olefin resin instead of the vinyl chloride resin which has conventionally been mainstream, and thus, when discarded or burned, generates toxic chlorinated products. Is extremely low and is also preferable from the viewpoint of environmental hygiene.

Further, as the olefin-based resin, an olefin-based thermoplastic elastomer comprising a blend of an isotactic polypropylene (hard segment) and an atactic polypropylene (soft segment), an isotactic polypropylene (hard segment) and an attack polypropylene ( Soft segment), blended with a compound having a polar functional group by graft polymerization, or ethylene / propylene / butene copolymer, when composed of any of thermoplastic elastomers, especially with the base sheet Excellent interlayer adhesion.

In addition, when the decorative sheet is bent, uneven and insufficient elongation (so-called necking) does not occur, and no stress is locally concentrated on the bent portion to cause whitening or cracking. .

[Brief description of the drawings]

FIG. 1 is a schematic view showing an outline of a manufacturing apparatus according to a decorative sheet manufacturing method of the present invention.

FIG. 2 is a cross-sectional view of the decorative sheet manufactured in Example 1.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Decorative sheet by the manufacturing method of this invention, 2 ... Olefin-based resin sheet, 3 ... Ozone generator, 4,19 ... Base sheet, 5 ... Cooling roll and emboss roll, 6 ... Impression roll, 7 ... Base Roll around which the sheet is wound, 8 ... adhesive, 9 ... T die, 10 ... colored pigment, 11 ... polyethylene sheet, 12 ... primer layer, 13 ... colored solid layer, 1
4 ... Adhesive layer, 15 ... Picture layer, 16 ... Olefin resin layer, 17 ... Emboss processing, 18 ... Top coat layer, 20
... Coating roll, 21 ... Roll

Claims (2)

[Claims] 1. A method for producing a decorative sheet, comprising a step of laminating a base sheet and a surface sheet made of an olefin resin through an adhesive layer, wherein the base sheet and the olefin resin are bonded between the base sheet and the olefin resin. A method for producing a decorative sheet, comprising performing ozone spraying treatment on the surface of the olefin-based resin before the step of laminating via an agent layer. 2. The olefin resin of the topsheet is an olefin thermoplastic elastomer comprising a blend of an isotactic polypropylene (hard segment) and an atactic polypropylene (soft segment), and an isotactic polypropylene (hard segment). Graft polymerized with a compound having a polar functional group to a blend with Attack Polypropylene (Soft Segment) or ethylene / propylene /
A thermoplastic elastomer of a butene copolymer, wherein the base sheet is a composition obtained by adding a rubber and an inorganic filler to high-density polyethylene or polypropylene, or any of an ethylene-propylene-butene copolymer. And, the adhesive is a two-component curable urethane resin, after applying an adhesive on a base sheet in advance to form an adhesive layer,
2. The method for producing a decorative sheet according to claim 1, wherein an ozone sprayed surface of a topsheet melt-extruded from a T-die and subjected to an ozone spray treatment is laminated on the adhesive layer.