JP2005119064A - Decorative sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative sheet having high weatherability enabling even exterior use such as an entrance door, a window frame or the like, excellent in the heat-resistant adhesiveness or humidity-resistant adhesiveness between a plurality of thermoplastic resin layers and easy to manufacture. <P>SOLUTION: In the decorative sheet obtained by laminating at least two thermoplastic resin layers 2 and 5 through an adhesive layer 4, the adhesive layer 4 is based on a two-pack type curable polyurethane resin having a polycarbonate skeleton. Each of at least two thermoplastic resin layers 2 and 5 is desirably constituted of a polyolefinic resin, a polyester resin or an acrylic resin. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a decorative sheet for use in interior and exterior materials of buildings such as houses, building materials such as construction materials and fittings, furniture fixtures, vehicle interiors, surface makeup of residential equipment and home appliances, etc. In particular, it relates to a highly weather-resistant decorative sheet suitable for surface decoration of exterior building components that require weather resistance and heat resistance, such as entrance doors, window frames, terraces, garages, aluminum props, etc. It is.

  In recent years, decorative sheets for exterior applications such as entrance doors include surface protective layers, transparent upper base thermoplastic resin layers (surface protective sheets), and colored lower base thermoplastic resin layers (base sheet) with UV absorbers and hindered amine light. A highly weather-resistant decorative sheet is used in which a stabilizer or the like is added and the pattern layer is also a weather-resistant pigment system or a binder resin using a weather-resistant material (Patent Documents 1 and 2).

  However, such a decorative sheet is generally configured by laminating a plurality of thermoplastic resin layers by a dry laminating method, and the adhesive used therefor is generally used for soft packaging materials and the like. The same two-component curable polyurethane resin composed of a blend of polyester polyol and isocyanate (two-component curable polyester polyurethane resin) is often used. There are problems such as deterioration and hydrolysis degradation due to the action of humidity, and the weather resistance is not always sufficient.

  As a method for laminating a plurality of thermoplastic resin layers, in addition to the dry laminating method described above, a thermal laminating method is also used. However, the heat laminating method has a problem in that it is difficult to obtain necessary adhesive strength, particularly heat resistant adhesive strength, in principle. In particular, as a part or all of the plurality of thermoplastic resin layers, when using a polyolefin-based resin, the range of temperature conditions that can be thermally bonded is very narrow, and because it is too high, the sheet breaks and stretches, Lamination defects such as deformation and heat deterioration will occur. Further, when heat laminating is performed in a low temperature range where these disadvantages do not occur, the laminate strength is extremely low, and it is impossible to obtain a sheet that can be used practically as a decorative sheet.

  Instead of directly laminating the base sheet and the surface protective sheet directly, a method of providing a thermoadhesive resin layer made of vinyl chloride-acrylic resin between them has also been proposed (Patent Document 3). According to this method, by performing thermal lamination by interposing a heat-adhesive resin layer that is sufficiently thermally activated and expresses adhesiveness in a low-temperature region where occurrence of breakage, elongation, deformation, thermal deterioration, etc. of the sheet does not occur, There is an advantage that sufficient laminate strength can be achieved without causing poor lamination.

  However, since the above heat-adhesive resin layer is made of a resin that is essentially inferior in heat resistance, the resulting decorative sheet is inferior in heat resistance. For example, it is ignited by direct sunlight in exterior applications. If this occurs, there is a problem that the heat-adhesive resin layer is softened by the heat and the surface protective sheet is peeled off from the base sheet. This problem will theoretically be improved if a heat-adhesive resin with a high heat softening temperature is used, but if this is done, it will inevitably require an increase in the laminating temperature. This leads to poor lamination such as surface gloss change, drawdown, breakage, elongation, deformation, and heat deterioration, and the intended purpose cannot be achieved.

  Therefore, a cross-linking agent such as an isocyanate compound is blended in the heat-adhesive resin, and the adhesiveness is expressed by heat at the time of laminating to adhere the base sheet and the surface protective sheet. A method of improving the heat resistance after laminating by causing a crosslinking reaction inside is also conceivable (Patent Document 4). However, according to such a method, after applying the heat-adhesive resin to the base sheet, if a time is taken until the heat laminating process, the cross-linking reaction proceeds during that time. Since it will disappear, it is necessary to carry out heat lamination immediately. Therefore, the progress management of the decorative sheet manufacturing process is cumbersome, and it is not possible to prepare a large amount of printed adhesive base sheet coated with heat-adhesive resin. However, it is very difficult.

Prior art document information.
Utility Model Registration No.3051179 JP-A-11-240113 JP-A-9-300559 JP 2000-326450 A

  The present invention has been made to solve the above-mentioned problems in the prior art, and is a highly weather-resistant decorative sheet that can be used for exterior applications such as entrance doors and window frames, and has a plurality of layers of heat. An object of the present invention is to provide a decorative sheet that is excellent in heat-resistant adhesiveness and moisture-resistant adhesiveness between plastic resin layers and is easy to manufacture.

  The decorative sheet of the present invention is a decorative sheet obtained by laminating two or more thermoplastic resin layers with an adhesive layer interposed therebetween, and the adhesive layer is mainly composed of a two-component curable polyurethane resin having a polycarbonate skeleton. It is characterized by doing.

  Each of the two or more thermoplastic resin layers is made of a polyolefin resin, a polyester resin, or an acrylic resin.

  The decorative sheet of the present invention is obtained by laminating two or more thermoplastic resin layers through an adhesive layer mainly composed of a two-component curable polyurethane resin having a polycarbonate skeleton. It can be produced easily and efficiently by the process, and there are no problems such as insufficient heat resistance and complicated process control as in the case of the conventional thermal laminating method. Compared to a certain two-component curable polyester polyurethane resin, there is no problem such as yellowing due to the action of ultraviolet rays or lowering of adhesion due to hydrolysis deterioration due to the action of humidity, and the weather resistance is remarkably improved. A decorative sheet can be obtained.

  If the typical embodiment of the decorative sheet of this invention is given, as shown in FIG. 1, the pattern layer 4 is formed on the surface of the colored lower base thermoplastic resin layer (base material sheet) 5, and on the pattern layer 4 A transparent thermoplastic resin layer (surface protective sheet) 2 is laminated on the adhesive layer 3, and a surface protective layer 1 is formed on the surface of the transparent thermoplastic resin layer 2. And the adhesive layer 3 in this structure is comprised with the adhesive agent for dry laminates which has as a main component the 2 liquid curing type polyurethane-type resin which has a polycarbonate frame | skeleton.

In the decorative sheet, the surface protective layer 1 may be an isocyanate-added acrylic polyol type polyurethane resin, ionizing radiation curable resin, or the like in consideration of surface hardness and adhesion, but is formulated with weather resistance taken into consideration. The coating amount after drying is desirably 3 to 15 g / m ² . As the isocyanate compound, an aliphatic group (including an alicyclic group) is preferable in consideration of weather resistance. The aromatic system may turn yellow and is appropriately selected depending on the intended use. Typical examples of the aliphatic system include hexamethylene diisocyanate and isophorone diisocyanate.

  In order to perform weather resistance prescription, a weather resistance prescription agent such as an ultraviolet absorber (benzotriazole, triazine, benzophenone, etc.) is added to the resin. The added part may be added according to the desired weather resistance, but is 0.1 to 50% by weight, preferably 1 to 30% by weight, based on the resin solid content.

  Among the ultraviolet absorbers, 2- (2-hydroxy-5-tert-butylphenyl) -2H-benzotriazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [ 2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) benzotriazole, 2- (3 -T-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3 , 5-Di-t-amyl-2-hydroxyphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) ben Triazole and mixtures thereof, modified products, polymers, derivatives.

  Examples of triazines include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] phenol, 2- [4-[(2-hydroxy- 3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [4-[(2-hydroxy-3- Tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2,4-bis (2,4-dimethylphenyl)- Examples include 6- (2-hydroxy-4-iso-octyloxyphenyl) -s-triazine and mixtures, modified products, polymers, and derivatives thereof. Further, examples of the benzophenone series include octabenzone, modified products, polymers, and derivatives.

  Since it is desired to bond with the resin component by crosslinking by addition of isocyanate, an ultraviolet absorber having a hydroxyl group is suitable.

  In addition, a hindered amine light stabilizer is added to prevent the resin itself from being deteriorated by light, heat, water or the like. The added part may be added according to the desired weather resistance, but is 0.1 to 50% by weight, preferably 1 to 30% by weight, based on the resin solid content.

  As a hindered amine light stabilizer, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] butyl Malonate, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, methyl (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis (2,2) decanoic acid 2,6,6-tetramethyl-1 (octyloxy) -4-piperidinyl) ester, etc., and mixtures, modified products, polymers, derivatives and the like thereof.

  In addition, you may perform the well-known formulation which considered contamination resistance, abrasion resistance, etc.

  The kind of thermoplastic resin which comprises the transparent thermoplastic resin layer 2 is not specifically limited, For example, using well-known arbitrary thermoplastic resins conventionally used as a raw material of the surface protection sheet for such a decorative sheet may be used. I can do it. Specifically, for example, polyolefin resins such as polyethylene, polypropylene, polybutene, and polymethylpentene, polyolefin resins such as ethylene-vinyl acetate copolymer or a saponified product thereof, and ethylene- (meth) acrylic acid (ester) copolymer. Polyester such as copolymer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyarylate, polycarbonate, copolymerized polyester (typically known as PET-G which is a 1,4-cyclohexanedimethanol copolymerized polyethylene terephthalate resin) Resins, acrylic resins such as polymethyl methacrylate, polyamide resins such as 6-nylon, 6,6-nylon, 6,10-nylon and 12-nylon, styrene resins such as polystyrene, AS resin and ABS resin Fluorine such as fat, cellulose acetate, nitrocellulose fiber derivatives, chlorinated resins such as polyvinyl chloride and polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, etc. Resin or the like, or two or more kinds of copolymers or mixtures selected from these, mixtures, composites, laminates, and the like can be used.

  However, considering the adaptation to environmental problems that are becoming social problems in recent years, the use of the above-mentioned chlorine-based resins and fluorine-based resins is not very preferable, and the resin does not contain halogen elements such as chlorine and fluorine. That is, it is preferable to use a non-halogen resin. Above all, including market price, distribution volume, ease of procurement, balance between appropriate flexibility and strength as a decorative sheet material, suitability for bending, cutting, cutting, etc., wear resistance and solvent resistance It is most preferable to use a thermoplastic resin selected from polyolefin resins, polyester resins, and acrylic resins from the viewpoint of various surface properties such as surface properties and weather resistance.

  Various homopolymers and copolymers such as those listed above are known as polyolefin resins. Among them, the most suitable as a material for a decorative sheet is a polypropylene resin, that is, a propylene-based single component. Or a copolymer, specifically, for example, a homopolypropylene resin, a random polypropylene resin, a block polypropylene resin, and a polypropylene crystal part, and an α-olefin having 2 to 20 carbon atoms other than propylene, preferably Examples thereof include a propylene-α-olefin copolymer containing 15 mol% or more of a comonomer of ethylene, butene-1, 4-methylpentene-1, hexene-1, or octene-1. Further, an ethylene-α-olefin copolymer, an ethylene-propylene copolymer rubber, an ethylene-propylene-nonconjugated diene copolymer rubber, a styrene-butadiene copolymer rubber or its hydrogen, which are usually used for softening polypropylene resins. A modifier such as an additive can also be added.

  Among the above polypropylene resins, random polypropylene resin or homopolypropylene resin can be produced without drawing down, breaking, or necking even if the processing temperature is increased during sheet processing such as laminating or post-processing such as lapping. Easy and most desirable.

  Examples of the acrylic resin include various thermoplastic resins obtained by singly or copolymerizing an acrylic acid derivative such as acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, acrylic ester or methacrylic ester as a main component. Can be mentioned. Among them, resins mainly composed of methacrylic acid esters such as methyl methacrylate, such as long-chain alkyl esters of methacrylic acid such as butyl methacrylate, acrylic acid esters such as methyl acrylate, methacrylic acid or acrylic acid, etc. A monomer selected from the group consisting of a copolymer component, and a rubber component such as styrene-butadiene rubber or methyl methacrylate-butadiene rubber is graft-copolymerized, block-copolymerized or blended to provide flexibility and thermoformability. An improved resin or the like can be preferably used.

  Among the acrylic resins described above, the resin sheet having a glass transition point of 90 ° C. or higher is used for wrapping a decorative sheet on an aluminum base material for exterior use, etc., even if the surface temperature exceeds 60 ° C. It is most desirable because it does not easily change its gloss.

  The surface of the transparent thermoplastic resin layer 2 is preferably subjected to a surface treatment in order to improve adhesion with a coating resin applied for forming the surface protective layer 1. Generally, corona discharge treatment is performed. Moreover, when using polyolefin-type resin, in order to improve adhesiveness, you may provide an adhesive resin layer on the surface, or may blend adhesive resin. As the adhesive resin, an acid-modified acid obtained by graft copolymerization of an unsaturated carboxylic acid such as maleic acid, itaconic acid, acrylic acid or methacrylic acid or an anhydride thereof, such as a polypropylene resin or a polyethylene resin. A modified polyolefin resin or the like can be used.

  The adhesive layer 3 is for bonding the transparent thermoplastic resin layer 2 and the colored lower base thermoplastic resin layer 5, and in the present invention, to improve adhesion and hydrolysis resistance (moisture resistance). In addition, it is important to use an adhesive mainly composed of a two-component curable polyurethane resin having a polycarbonate skeleton.

  As the two-component curable polyurethane resin having a polycarbonate skeleton, a polycarbonate diol obtained by polymerizing with a diisocyanate using another diol as a chain extender can be used. As the chain extender, an aliphatic type having a relatively low molecular weight is generally used, and examples thereof include ethylene glycol, propylene glycol, and butanediol.

  In order to improve adhesion, a polycarbonate polyol (having 3 or more hydroxyl groups per molecule) modified by introducing a hydroxyl group into the side chain of the carbonate skeleton may be used as a monomer.

  As the diol, chain aliphatic diols are generally used, and ethylene glycol, propylene glycol, butanediol and the like are often used.

  As the diisocyanate, in view of weather resistance, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI) and the like which are not easily yellowed are suitable.

  Polymerization is performed with carbonate polyol (or carbonate diol), diols and isocyanate as described above to adjust the molecular weight, hydroxyl value, and the like, thereby ensuring the stability as a coating resin. A polyol resin having a polycarbonate skeleton obtained in this manner is used as a main agent, an isocyanate compound is added as a curing agent immediately before coating, and lamination is performed by a normal dry laminating method.

  In order to perform weather resistance prescription, a weather resistance prescription agent such as an ultraviolet absorber (benzotriazole, triazine, benzophenone, etc.) may be added to the resin. The added part may be added according to the desired weather resistance, but is 0.1 to 50% by weight, preferably 1 to 30% by weight, based on the resin solid content.

  Since it is desired to bond with the resin component by crosslinking by addition of isocyanate, an ultraviolet absorber having a hydroxyl group is suitable.

  Further, a hindered amine light stabilizer may be added in order to prevent the resin itself from being deteriorated by light, heat, water or the like. The added part may be added according to the desired weather resistance, but is 0.1 to 50% by weight, preferably 1 to 30% by weight, based on the resin solid content.

  The pattern layer 4 may be formed by a common printing method such as gravure printing using a common printing ink. However, as the pigment and binder contained in the printing ink, those having good weather resistance are selected. Moreover, you may give weatherproof prescriptions, such as a ultraviolet absorber and a light stabilizer.

  Examples of the colored base thermoplastic resin layer 5 include polyolefin resins such as polyethylene, polypropylene, polybutene, and polymethylpentene, ethylene-vinyl acetate copolymers or saponified products thereof, and ethylene- (meth) acrylic acid (ester) copolymers. Polyolefin copolymers such as polymers, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyarylate, polycarbonate, copolymerized polyester (typically known as PET, which is typically 1,4-cyclohexanedimethanol copolymerized polyethylene terephthalate resin) -G) and other polyester resins, polymethyl methacrylate and other acrylic resins, 6-nylon, 6,6-nylon, 6,10-nylon, 12-nylon and other polyamide resins, polystyrene, AS resin, Styrene resins such as BS resin, fiber derivatives such as cellulose acetate and nitrocellulose, chlorine resins such as polyvinyl chloride and polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, polytetrafluoroethylene, and ethylene-tetrafluoroethylene Fluorine resins such as copolymers, or two or more kinds of copolymers or mixtures selected from these, mixtures, composites, laminates, and the like can be used.

  However, considering the adaptation to environmental problems that are becoming social problems in recent years, the use of the above-mentioned chlorine-based resins and fluorine-based resins is not very preferable, and the resin does not contain halogen elements such as chlorine and fluorine. That is, it is preferable to use a non-halogen resin. Above all, including the market price, distribution volume, and ease of procurement, the balance between moderate flexibility and strength as a decorative sheet material, suitability for bending, cutting, cutting, etc., wear resistance and solvent resistance It is most desirable to use a thermoplastic resin selected from a polyolefin resin, a polyester resin, and an acrylic resin in view of various aspects such as surface physical properties and weather resistance.

  Various homopolymers and copolymers such as those listed above are known as polyolefin resins. Among them, the most suitable as a material for a decorative sheet is a polypropylene resin, that is, a single or copolymer mainly composed of propylene. Specifically, for example, a homopolypropylene resin, a random polypropylene resin, a block polypropylene resin, and a polypropylene crystal part, and an α-olefin having 2 to 20 carbon atoms other than propylene, preferably ethylene, Examples thereof include a propylene-α-olefin copolymer containing 15 mol% or more of a comonomer of butene-1, 4-methylpentene-1, hexene-1, or octene-1. In addition, ethylene-α-olefin copolymers, ethylene-propylene copolymer rubbers, ethylene-propylene-nonconjugated diene copolymer rubbers, styrene-butadiene copolymer rubbers, or hydrogenated products thereof, which are usually used for softening polypropylene resins It is also possible to add a modifier such as

  Among the above polypropylene resins, random polypropylene resin or homopolypropylene resin is easy to manufacture without drawing down, breaking, or necking even if the processing temperature is increased during sheet processing such as laminating or after processing such as lapping. Most desirable.

  In general, the decorative sheet as in the present invention often requires a concealing property against the color and defects of the surface of the adherend substrate. Therefore, in order to give the target decorative sheet sufficient concealability, it is desirable to add a concealing pigment to the thermoplastic resin constituting the colored lower base thermoplastic resin layer 5 to color the concealment. In addition, instead of making the colored base thermoplastic resin layer 5 concealable, a concealing solid layer made of a printing ink or paint containing a concealing pigment may be provided on the front or back surface, or both may be used in combination. it can.

  As the concealing pigment, it is desirable to use an inorganic pigment having a high refractive index and excellent concealing property. Specifically, for example, yellow lead, yellow iron oxide, titanium yellow, barium yellow, aureoline, molybdate orange, cadmium red, petal, red lead, cinnabar, mars violet, manganese violet, cobalt violet, cobalt blue, cerulean blue , Ultramarine, bituminous, emerald green, chrome vermilion, chromium oxide, viridian, iron black, carbon black and other pigments such as titanium oxide (titanium white, titanium white), zinc oxide (zinc white), basic lead carbonate (Lead white), white pigments such as basic lead sulfate, zinc sulfide, lithopone, and titanox can be used.

  Above all, it is excellent in concealability and light resistance, and is suitable for decorative sheets in terms of design and color tone. Colored pigments are petals, iron oxide pigments such as yellow iron oxide and iron black, and white pigments are oxidized. It is most desirable to use a titanium pigment. Of course, other concealing or non-concealing inorganic pigments or organic pigments can be used together for the purpose of adjusting the color tone, in which case the inorganic pigments are organic pigments such as cobalt blue, carbon black, etc. If it is red, diketopyrrolopyrrole, monoazo, quinacridone, bromoanthanthrone, etc., yellow is isoindolinone, monoazo, disazo, benzimidazolone, anthraquinone, etc., blue is phthalocyanine blue, etc. It is preferable to use excellent pigments. In addition, for example, metal powder pigments such as gold powder, silver powder, copper powder, aluminum powder, bronze powder, pearl luster pigments such as fish scale powder, basic lead carbonate, bismuth oxide chloride, titanium oxide-coated mica, and fluorescent pigments In addition, extender pigments such as nocturnal pigment, silica, calcium carbonate, barium sulfate and the like can be used in combination as appropriate.

  In addition, the thermoplastic resin constituting the transparent thermoplastic resin layer 2 and the colored lower base thermoplastic resin layer 5 may include, for example, an antioxidant, an ultraviolet absorber, and a light stabilizer depending on the intended use of the decorative sheet. One or more of various conventionally known additives such as a heat stabilizer, a plasticizer, a lubricant, an antistatic agent, a flame retardant, and a filler may be added.

  Examples of antioxidants include phenol-based, sulfur-based, phosphorus-based and the like, and ultraviolet absorbers include, for example, benzophenone-based, benzotriazole-based, triazine-based, salicylate-based, cyanoacrylate-based, formamidine-based, oxanilide-based, and other light stabilizers. For example, hindered amines, nickel complexes, etc., heat stabilizers such as hindered phenols, sulfurs, hydrazines, etc., and plasticizers depending on the type of resin, for example, phthalates, phosphates, etc. , Aliphatic dibasic acid ester type, oxybenzoic acid ester type, epoxy type, polyester type, etc., as the lubricant, for example, fatty acid ester type, fatty acid type, metal soap type, fatty acid amide type, higher alcohol type, paraffin type, etc. Examples of inhibitors include cationic, anionic and nonionic Examples of flame retardants such as zwitterion, bromine, phosphorus, chlorine, nitrogen, aluminum, antimony, magnesium, boron, zirconium, etc., and fillers such as calcium carbonate, barium sulfate, talc , Wax stone, kaolin and the like are used in one or a mixture of two or more.

  Polyol having a polycarbonate skeleton with an average molecular weight of 30000 and a hydroxyl value of 12 was synthesized with hexamethylene diisocyanate using polycarbonate glycol (CD220PL; manufactured by Daicel Chemical Industries, Ltd.) as a chain extender. Further, 2- (2H-benzotriazol-2-yl) -4,6-di-t-pentylphenol (TINUVIN328; manufactured by Ciba Specialty Chemicals Co., Ltd.), which is a benzotriazole-based ultraviolet absorber as an ultraviolet absorber. 5% by weight of decanedioic acid bis (2,2,6,6-tetramethyl-1 (octyloxy) -4-piperidinyl) ester (TINUVIN123; Ciba Specialty) as a light stabilizer Chemicals Co., Ltd.) was blended in an amount of 5% by weight and diluted with methyl ethyl ketone (MEK) for viscosity adjustment to obtain a main resin with a solid content of 24% by weight.

  On the other hand, as a polyisocyanate compound serving as a crosslinking agent (curing agent), adduct-type hexamethylene diisocyanate (HDI) was adjusted with MEK so that the solid content was 75% by weight to obtain a curing agent. A coating agent was added by adding 15 parts by weight of a curing agent to 100 parts by weight of the main resin.

A two-component curable urethane resin ink comprising 3% by weight of an isocyanate curing agent in a polyester polyol vehicle on the surface of a colored random polypropylene resin film (Rivesta-TOP original fabric; manufactured by Riken Technos Co., Ltd.) having a thickness of 150 μm. (Lamister; manufactured by Toyo Ink Mfg. Co., Ltd.), a pattern is printed by a gravure printing method, and the adhesive is applied on the printed surface to a coating amount of 10 g / m ² after drying by a gravure coating method And dried at 60 ° C. Thereafter, a transparent polyolefin resin film having a thickness of 80 μm (Revesta-TPO; manufactured by Riken Technos Co., Ltd.) as a transparent upper base thermoplastic resin layer is laminated on the adhesive-coated surface at a film surface temperature of 60 ° C. Then, a coating amount of 10 g / m ² after drying was applied to the isocyanate-added two-part acrylic polyol type polyurethane resin-based surface protective layer to prepare a decorative sheet of the present invention.

  As the colored thermoplastic resin layer in Example 1 above, printing of acrylic / vinyl acetate resin binder on a colored copolymerized polyethylene terephthalate resin film (Rivesta original fabric; manufactured by Riken Technos Co., Ltd.) instead of a colored random polypropylene resin film A decorative sheet according to the present invention was produced in the same manner as in Example 1 except that a pattern was printed using ink (manufactured by Toyo Ink Mfg. Co., Ltd., solvent not containing toluene).

<Comparative Example 1>
In Example 1 above, a decorative sheet was prepared in the same manner as in Example 1 above, except that the adhesive was changed to a two-component curable polyester polyurethane resin-based adhesive comprising a polyester polyol main component and an isocyanate curing agent. .

<Comparative example 2>
In Example 2, a decorative sheet was prepared in the same manner as in Example 2 except that the adhesive was changed to a two-part curable polyester polyurethane resin-based adhesive comprising a polyester polyol main component and an isocyanate curing agent. .

<Evaluation>
For the decorative sheets of Examples 1-2 and Comparative Examples 1-2, an accelerated weather resistance test (metal weather, xenon weatherometer, 40 ° C. and 90% RH constant temperature and humidity chamber) was performed as follows, before and after the test. When the delamination strength was measured, the results were as shown in Table 1 below.

a) Metal Weather Testing Machine (Daipura Wintes Co., Ltd.)
Daipla Metal Weather (KU-R5DCI-A)
Light source lamp: MW-60W, filter: KF-1
Condition: Illuminance 65 mW / cm ²
Irradiation (53 ° C., 70% RH) 20 h,
Dark condensation (30 ° C, 95% RH) 4h,
Stop (30 ° C., 95% RH) 0.1 hour end.

            Shower is 30s before and after dark condensation.

            The above 24.01 hours are one cycle and four cycles are performed.

b) ATLAS Xenon Weatherometer Ci4000 (Toyo Seiki Seisakusho)
Specifications: Illuminance: 550 W / m ² (290 nm-800 nm),
60W / m ² (300nm-400nm)
(All with external and internal filters)
External filter: Soda lime
Internal filter: CIRA
18 dispersed water in 120 minutes
Black standard panel temperature: 65 ° C
Temperature inside the tank: 40 ° C
Humidity in the tank: 65% RH.

  c) Delamination strength: 180 degree T-type peeling between the transparent thermoplastic resin layer and the colored lower base thermoplastic resin layer, and a crosshead speed of 50 mm / min.

  d) Appearance: Visual observation.

Sectional drawing of an example of the decorative sheet of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface protective layer 2 Transparent thermoplastic resin layer 3 Adhesive layer 4 Picture layer 5 Colored lower base thermoplastic resin layer

Claims (2)

  A decorative sheet formed by laminating two or more thermoplastic resin layers with an adhesive layer interposed therebetween, wherein the adhesive layer is mainly composed of a two-component curable polyurethane resin having a polycarbonate skeleton. Sheet.   The decorative sheet according to claim 1, wherein each of the two or more thermoplastic resin layers is made of a polyolefin resin, a polyester resin, or an acrylic resin.

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