Decorative sheet and decorated resin molded article

Abstract

A decorative sheet having a barrier layer with good resistance to solid fragrances and good adhesion is provided. [Solution] A decorative sheet (10) is provided, which has at least a base sheet (1), a barrier layer (4), and a surface protective layer (5) in this order, the barrier layer containing a vinyl alcohol-based resin and a polyurethane resin, and the vinyl alcohol-based resin is a modified polyvinyl alcohol resin having hydrophobic groups other than acetate groups.

Description

Technical Field

[0001] The present disclosure relates to a decorative sheet and a decorative resin molded article.

Background Art

[0002] For example, in vehicle interior materials, a decorative resin molded article in which a decorative sheet is laminated on the surface of a resin molded article is used.

[0003] Patent Document 1 discloses a decorative sheet having at least a surface protection layer on a base material, wherein the surface protection layer is a three-dimensional molding decorative sheet made of a cured product of a composition containing polycarbonate (meth) acrylate and polyfunctional (meth) acrylate in a predetermined ratio. This technology aims to provide a decorative sheet having a surface protection layer capable of achieving both scratch resistance and three-dimensional moldability.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the fragrance component contained in the solid fragrance agent penetrates from the surface protection layer side of the decorative sheet and reaches the base material sheet, swelling of the base material sheet may occur. On the other hand, in order to improve the solid fragrance agent resistance, it is assumed to provide a barrier layer on the decorative sheet. Although a barrier layer containing a vinyl alcohol-based resin is likely to improve the solid fragrance agent resistance, it tends to have low adhesion.

[0006] The present disclosure has been made in view of the above circumstances, and the main object thereof is to provide a decorative sheet having a barrier layer with good solid fragrance agent resistance and adhesion.

Means for Solving the Problems

[0007] In the present disclosure, a decorative sheet is provided which has at least a base material sheet, a barrier layer, and a surface protective layer in this order, and the barrier layer contains a vinyl alcohol-based resin and a polyurethane resin.

[0008] According to the present disclosure, since the barrier layer contains a vinyl alcohol-based resin and a polyurethane resin, a decorative sheet having a barrier layer with good solid fragrance resistance and adhesiveness can be obtained.

[0009] In the above disclosure, the barrier layer may have a peak in the infrared absorption spectrum in the range of 1130 cm -1 or more and 1160 cm -1 or less.

[0010] In the above disclosure, in the barrier layer, the ratio of the polyurethane resin to the total of the vinyl alcohol-based resin and the polyurethane resin may be 5% by mass or more and 40% by mass or less.

[0011] In the above disclosure, the vinyl alcohol-based resin may be a modified polyvinyl alcohol resin having a hydrophobic group other than an acetic acid group.

[0012] In the above disclosure, the hydrophobic group may have a reactive group.

[0013] In the above disclosure, the reactive group may be a reactive carbonyl group.

[0014] In the above disclosure, the modified polyvinyl alcohol resin may have an acetoacetyl group having the reactive carbonyl group as the hydrophobic group.

[0015] In the above disclosure, the surface protective layer may contain a polyurethane resin.

[0016] In the above disclosure, the surface protective layer has a Martens hardness of 40 N / mm2 It may be as follows.

[0017] In the above disclosure, the surface protection layer and the barrier layer may be in direct contact.

[0018] Further, in the present disclosure, there is provided a decorated resin molded article having a resin molded article and a decorative sheet located on the surface of the resin molded article, wherein the decorative sheet has at least a base sheet, a barrier layer, and a surface protection layer in this order, and the barrier layer contains a vinyl alcohol-based resin and a polyurethane resin.

[0019] According to the present disclosure, by using the above-described decorative sheet, it is possible to obtain a decorated resin molded article having a barrier layer with good solid fragrance resistance and adhesion.

Effects of the Invention

[0020] In the present disclosure, there is an effect that it is possible to provide a decorative sheet having a barrier layer with good solid fragrance resistance and adhesion.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0022] The decorative sheet and the decorated resin molded article in the present disclosure will be described in detail.

[0023] A. Decorative Sheet FIG. 1 is a schematic cross-sectional view showing an example of the decorative sheet in the present disclosure. The decorative sheet 10 shown in FIG. 1 has a base sheet 1, a pattern layer 2, a primer layer 3, a barrier layer 4, and a surface protection layer 5 in this order. The barrier layer 4 contains a vinyl alcohol-based resin and a polyurethane resin.

[0024] According to the present disclosure, by including a vinyl alcohol-based resin and a polyurethane resin in the barrier layer, a decorative sheet having a barrier layer with good solid fragrance resistance and adhesion can be obtained. As described above, when the fragrance component contained in the solid fragrance penetrates from the surface protective layer side of the decorative sheet and reaches the base material sheet, swelling of the base material sheet may occur. On the other hand, in order to improve the solid fragrance resistance, it is assumed to provide a barrier layer on the decorative sheet. The barrier layer containing a vinyl alcohol-based resin is likely to improve the solid fragrance resistance, but tends to have low adhesion.

[0025] Here, the vinyl alcohol-based resin exhibits good solid fragrance resistance by crystallizing through hydrogen bonding. On the other hand, the barrier layer in the present disclosure contains not only a vinyl alcohol-based resin but also a polyurethane resin. When a different resin such as a polyurethane resin is added to the vinyl alcohol-based resin, it is assumed that the crystallization of the vinyl alcohol-based resin may be inhibited. However, unexpectedly, it has been found that even when a polyurethane resin is used, crystallization of the vinyl alcohol-based resin or a structure approximating a crystal occurs, and good solid fragrance resistance can be maintained. Furthermore, since the barrier layer in the present disclosure contains a polyurethane resin, the adhesion can be improved. Thus, by including a vinyl alcohol-based resin and a polyurethane resin in the barrier layer, both solid fragrance resistance and adhesion can be achieved.

[0026] 1. Barrier layer The barrier layer in the present disclosure contains a vinyl alcohol-based resin and a polyurethane resin.

[0027] (1) Vinyl alcohol-based resin The vinyl alcohol-based resin is a resin having a [-CH2-CH(OH)-] unit. Examples of the vinyl alcohol-based resin include copolymer resins using vinyl alcohol and polyvinyl alcohol resin (PVA).

[0028] Polyvinyl alcohol resin is generally a resin obtained by saponifying polyvinyl acetate. The saponification degree of the polyvinyl alcohol resin is not particularly limited, but it is preferably higher from the viewpoint of solid fragrance resistance. The saponification degree is, for example, 70 mol% or more, may be 80 mol% or more, may be 90 mol% or more, may be 95 mol% or more, or may be 99 mol% or more.

[0029] The average degree of polymerization of the polyvinyl alcohol resin is not particularly limited, but is, for example, 200 or more and 6000 or less, may be 300 or more and 4000 or less, or may be 400 or more and 2000 or less.

[0030] The polyvinyl alcohol resin may be a modified polyvinyl alcohol resin having a hydrophobic group other than an acetate group (-OCOCH3). By using such a modified polyvinyl alcohol resin, the hydrophobicity (water resistance) of the barrier layer can be improved, and a barrier layer with good sunscreen resistance (sunscreen cream resistance) can be obtained.

[0031] The modified polyvinyl alcohol resin preferably has a hydrophobic group other than an acetate group as a side chain. The hydrophobic group refers to a functional group having at least carbon and no OH group. The hydrophobic group may be linear, branched, or cyclic. From the viewpoint of crystallization of the vinyl alcohol-based resin, the hydrophobic group is preferably linear or branched. The number of carbon atoms of the hydrophobic group is, for example, 2 or more, may be 3 or more, or may be 5 or more. Examples of the hydrophobic group include a functional group represented by -OR. R has at least carbon. Examples of R include hydrocarbon groups such as an alkyl group having 3 or more carbon atoms, an alkenyl group having 3 or more carbon atoms, or an alkynyl group having 3 or more carbon atoms.

[0032] Examples of the alkyl group having 3 or more carbon atoms include an n-propyl group, isopropyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, 1-methylpentyl group, cyclopentylmethyl group, n-heptyl group, 1-ethylpentyl group, cyclohexylmethyl group, and n-octyl group. Examples of the alkenyl group having 3 or more carbon atoms include an allyl group, isopropenyl group, and butynyl group. Examples of the alkynyl group having 3 or more carbon atoms include a propynyl group, propargyl group, and butynyl group.

[0033] The hydrophobic group may have a reactive group. Specifically, in the functional group represented by -OR, R has at least carbon and may further have a reactive group. Examples of the reactive group include a reactive carbonyl group. The hydrophobic group may have only one reactive group or may have two or more reactive groups. Examples of the hydrophobic group having two reactive carbonyl groups include an acetoacetyl group (-OCOCH2COCH3).

[0034] The modified polyvinyl alcohol resin may have only one type of the above hydrophobic group or may have two or more types. Further, the modified polyvinyl alcohol resin may or may not have an acetic acid group.

[0035] On the other hand, examples of the copolymer resin using vinyl alcohol include a copolymer of acrylic acid or acrylate and vinyl alcohol, a copolymer of maleic anhydride or maleic acid or fumaric acid and vinyl alcohol, and a copolymer of ethylene and vinyl alcohol (EVOH). Examples of commercially available products of EVOH include Eval (manufactured by Kuraray Co., Ltd.) and Soarnol (manufactured by Mitsubishi Chemical Corporation).

[0036] The barrier layer may contain only one type of vinyl alcohol-based resin or may contain two or more types of vinyl alcohol-based resins.

[0037] (2) Polyurethane resin A polyurethane resin is a resin obtained by the reaction of a polyol and a polyisocyanate. Further, if necessary, in addition to the polyol and the polyisocyanate, a polyurethane resin may be obtained by further reacting a compound having a hydrophilic functional group in the molecule or a compound such as a chain extender.

[0038] Examples of the polyol include polyester polyol, polyether polyol, polycarbonate polyol, and polyolefin polyol.

[0039] Examples of the polyester polyol include condensates of low molecular diol components such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bis-hydroxyethoxybenzene, cyclohexanedimethanol, bisphenol A, and hydrogenated bisphenol A, and polyvalent carboxylic acids such as succinic acid, adipic acid, sebacic acid, dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, and biphenyldicarboxylic acid.

[0040] Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide copolymer (random and / or block copolymer), and polytetramethylene glycol.

[0041] The polycarbonate polyol is, for example, a compound obtained by reacting a diol with a compound serving as a carbonyl component. Examples of the above diol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methylpentanediol, neopentyl glycol, dipropylene glycol, bisphenol A, hydrogenated bisphenol A, trimethylolpropane, and cyclohexanedimethanol. On the other hand, the compound serving as the above carbonyl component is, for example, any compound selected from diesters of carbonic acid, phosgene, or their equivalents. Specific examples thereof include diesters of carbonic acid such as dimethyl carbonate, diethyl carbonate, diisopropyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate, phosgene, or halogenated formic acid esters such as methyl chloroformate, ethyl chloroformate, and phenyl chloroformate. The polycarbonate polyol is produced, for example, by a general production method such as a transesterification method of a diol and a carbonate ester or a phosgene method.

[0042] Examples of the polyolefin polyol include polybutadiene polyol, polyisoprene polyol, and their hydrogenated polyols.

[0043] Examples of the above polyisocyanate include aromatic polyisocyanate, araliphatic polyisocyanate, alicyclic polyisocyanate, and aliphatic polyisocyanate.

[0044] Examples of aromatic polyisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-dibenzyl diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, 1,3-phenylene diisocyanate, and 1,4-phenylene diisocyanate.

[0045] Examples of aromatic aliphatic polyisocyanates include tetraalkyldiphenylmethane diisocyanate, dialkyldiphenylmethane diisocyanate, and α,α,α,α-tetramethylxylylene diisocyanate.

[0046] Examples of alicyclic polyisocyanates include isophorone diisocyanate, hydrogenated xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, and 1,3-bis(isocyanatomethyl)cyclohexane.

[0047] Examples of aliphatic polyisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,6,11-undecanetriisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,5-diisocyanate, and 3-methylpentane-1,5-diisocyanate.

[0048] The weight average molecular weight of the polyurethane resin is not particularly limited, but it is preferably made as large as possible by introducing at least one of a branched structure and an internal cross-linked structure. The weight average molecular weight of the polyurethane resin is, for example, 10,000 or more, and may be 50,000 or more. On the other hand, the weight average molecular weight of the polyurethane resin is, for example, 15,000,000 or less, and may be 5,000,000 or less.

[0049] Further, the polyurethane resin may have a hydrophilic functional group in order to impart dispersibility in water. Examples of the hydrophilic functional group include a carboxyl group, a sulfonyl group, and the like. The hydrophilic functional group can be introduced by the following compounds. For example, carboxyl group-containing compounds such as dimethylolpropionic acid, dimethylolbutanoic acid, lactic acid, and glycine, sulfonic acid group-containing compounds such as taurine, and polyester polyols using as a raw material a compound containing at least one of a carboxyl group and a sulfonic acid group can be mentioned. Further, in order to increase the molecular weight of the polyurethane resin, a chain extender may be used. As the chain extender, diamine and polyamine that also functions to introduce an internal cross-linked structure are preferable. Examples of the diamine include ethylenediamine, trimethylenediamine, piperazine, and isophoronediamine, and examples of the polyamine include diethylenetriamine, dipropylenetriamine, and triethylenetetramine.

[0050] Furthermore, the polyurethane resin is preferably an aqueous polyurethane resin. The aqueous polyurethane resin is an emulsion of the urethane resin. The aqueous polyurethane resin may be non-reactive or reactive. The reactive aqueous polyurethane resin protects the terminal isocyanate group with a blocking agent. The aqueous polyurethane resin may be a water-soluble type or a self-emulsifying type. Both the water-soluble type and the self-emulsifying type have the hydrophilic functional group described above. The aqueous polyurethane resin preferably has an internal cross-linked structure in which the polyurethane resin is cross-linked in a network form. Further, the aqueous polyurethane resin preferably has a urea bond. A urea bond is formed by the reaction of an isocyanate group and an amine.

[0051] The barrier layer may contain only one type of polyurethane resin or may contain two or more types of polyurethane resins.

[0052] (3) Barrier layer The barrier layer in the present disclosure contains a vinyl alcohol-based resin and a polyurethane resin.

[0053] The barrier layer preferably has a peak in the range of 1130 cm -1 or more and 1160 cm -1 or less in the infrared absorption spectrum (IR spectrum). The peak associated with the crystallization of the vinyl alcohol-based resin is observed in the range of 1130 cm -1 or more and 1160 cm -1 or less. By having the barrier layer have a peak in the range of 1130 cm -1 or more and 1160 cm -1 or less, a decorated sheet having excellent solid air freshener resistance can be obtained. The infrared absorption spectrum of the barrier layer can be acquired, for example, by measuring the cross-sectioned and exposed barrier layer by the total reflection method (ATR method). The method of cross-sectioning may be, for example, a method of gradually shaving off the surface layer from the decorated sheet to expose the lower layers one by one, or a method of entirely exposing the cross-section using a device such as a microtome or a cutter knife. The former method is effective when the layer structure such as the number of layers and film thickness is known from cross-section observation. Also, in the latter method, in order to secure the measurement area, it is preferable to perform cross-sectioning by cutting the decorated sheet at an angle.

[0054] In the barrier layer, the proportion of the polyurethane resin with respect to the total of the polyvinyl alcohol resin and the polyurethane resin is, for example, 5% by mass or more, and may be 10% by mass or more, 15% by mass or more, or 20% by mass or more. If the proportion of the polyurethane resin is too small, good adhesion may not be obtained. On the other hand, the proportion of the polyurethane resin is, for example, 40% by mass or less, and may be 35% by mass or less, 30% by mass or less, or 25% by mass or less. If the proportion of the polyurethane resin is too large, good solid fragrance resistance may not be obtained.

[0055] The barrier layer may or may not contain a crosslinking agent that improves the crosslinking density of the vinyl alcohol-based resin. Examples of the crosslinking agent include dihydrazide compounds such as adipic acid dihydrazide (ADH); metal salts; boric acid; and polymer acids such as polyacrylic acid.

[0056] The barrier layer may be a cured product of a resin composition containing a vinyl alcohol-based resin and a polyurethane resin. The resin composition may contain a curing agent. Examples of the curing agent include carbodiimide-based curing agents and isocyanate-based curing agents. The carbodiimide-based curing agent is not particularly limited as long as it is a compound having a carbodiimide structure (-N=C=N-) in the molecule. Examples of the compound having a carbodiimide group include N,N'-dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide, and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride. Commercially available products include Carbodilite V-02, Carbodilite V-02-L2, Carbodilite SV-02, Carbodilite V-04, Carbodilite V-10, Carbodilite SW-12G, Carbodilite E-02, Carbodilite E-03A, and Carbodilite E-05 (all manufactured by Nisshinbo Chemical).

[0057] Examples of the isocyanate-based curing agent include aromatic isocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, polymethylene polyphenylene polyisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate, etc. Examples of the isocyanate compound also include aliphatic isocyanates such as 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane (1,6-hexamethylene diisocyanate, HDI), 1,6-diisocyanato-2,2,4-trimethylhexane, methyl 2,6-diisocyanatohexanoate (lysine diisocyanate), etc. Examples of the isocyanate compound further include alicyclic diisocyanates such as isophorone diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, etc.

[0058] The ratio of the curing agent contained in the resin composition is not particularly limited, but for example, it is 0.5 parts by mass or more, may be 1 part by mass or more, and may be 3 parts by mass or more with respect to 100 parts by mass of the resin. On the other hand, the ratio of the curing agent is, for example, 50 parts by mass or less, and may be 35 parts by mass or less with respect to 100 parts by mass of the resin.

[0059] In the present disclosure, the layer in direct contact with the barrier layer preferably contains a polyurethane resin. This is because when the layer in direct contact with the barrier layer contains a polyurethane resin, the adhesion between that layer and the barrier layer is improved. The layer in direct contact with the barrier layer is not particularly limited, and examples thereof include a surface protection layer, a primer layer, and a pattern layer. In particular, the layer in direct contact with one surface of the barrier layer and the layer in direct contact with the other surface of the barrier layer preferably each contain a polyurethane resin.

[0060] The barrier layer is disposed between the surface protection layer and the base material sheet in the decorative sheet. Further, at least one of the pattern layer and the primer layer, which will be described later, may be disposed between the barrier layer and the base material sheet.

[0061] As an example of a method for forming the barrier layer, a method of coating a resin composition containing a vinyl alcohol-based resin and a polyurethane resin can be mentioned. Examples of the coating method include general methods such as gravure coating, bar coating, roll coating, reverse roll coating, comma coating, etc. Further, when the resin composition contains a curing agent, usually, a curing treatment is performed on the uncured resin layer (uncured barrier layer) after coating. Examples of the curing treatment include heat treatment.

[0062] The heat treatment temperature is not particularly limited as long as a desired curing reaction occurs. For example, it may be 90 °C or higher, 120 °C or higher, or 150 °C or higher. On the other hand, the upper limit of the heat treatment temperature can be appropriately selected. The heat treatment method is not particularly limited, and a general heat treatment method can be adopted.

[0063] The thickness of the barrier layer is, for example, 1 μm or more, and may be 3 μm or more, or 5 μm or more. If the thickness is too small, the function as a barrier layer may decrease. On the other hand, the thickness of the barrier layer is, for example, 50 μm or less, and may be 30 μm or less, or 10 μm or less. If the thickness is too large, the three-dimensional formability may decrease.

[0064] 2. Surface protective layer The surface protective layer in the present disclosure is preferably a cured product of a resin composition containing at least a resin. The resin composition may contain a curing agent. The resin may be a thermosetting resin or an ionizing radiation curable resin such as an electron beam curable resin. Examples of the resin include a polyurethane resin and a fluororesin, and among them, a polyurethane resin is preferable. This is because a decorative sheet with good scratch resistance can be obtained. Note that the curing agent is the same as the content described in the above "1. Barrier layer".

[0065] The polyurethane resin is preferably a resin capable of reacting with a curing agent. The polyurethane resin is obtained by the reaction of a polyol and a polyisocyanate. Further, if necessary, in addition to the polyol and the polyisocyanate, a polyurethane resin may be obtained by further reacting a compound having a hydrophilic functional group in the molecule or a compound such as a chain extender.

[0066] The polyurethane resin (second polyurethane resin) in the surface protective layer and the polyurethane resin (first polyurethane resin) in the barrier layer may be the same resin or different resins. The details of the second polyurethane resin are the same as those of the first polyurethane resin described above. The second polyurethane resin is preferably an aqueous polyurethane resin. Further, the second polyurethane resin is particularly preferably a thermosetting polyurethane resin capable of accelerating the curing reaction simultaneously with the curing treatment of the barrier layer.

[0067] The surface protective layer preferably has a low Martens hardness. This is because a decorative sheet with good scratch resistance can be obtained. The Martens hardness of the surface protective layer is, for example, 40 N / mm 2 or less, and may be 35 N / mm 2 or less, and may be 30 N / mm 2 or less. On the other hand, the Martens hardness of the surface protective layer is, for example, 0.01 N / mm 2The above, 0.8 N / mm 2 may be the above, 3 N / mm 2 may also be the above.

[0068] The martensitic hardness can be adjusted, for example, by the crosslink density of the cured resin and the average molecular weight of the uncured resin. When the crosslink density of the cured resin increases, the martensitic hardness tends to increase. Also, the martensitic hardness can be adjusted by changing the amount of curing agent used.

[0069] The measurement of the martensitic hardness is performed by pressing an indenter into the surface protection layer. As the indenter, for example, a Vickers indenter can be used. Also, as the measuring instrument, for example, "PICODENTOR HM-500" (manufactured by Fisher Instruments Co., Ltd.) can be used. When the depth at which the indenter penetrates into the surface protection layer is sufficiently smaller than the thickness of the surface protection layer, the influence of other layers (for example, the base sheet) of the decorative sheet can be ignored. Specifically, when the depth at which the indenter penetrates into the surface protection layer is about 1 / 10 of the thickness of the surface protection layer, since the influence of other layers (for example, the base sheet) of the decorative sheet can be ignored, even if the decorative sheet itself is measured as the measurement object, it can be measured as the martensitic hardness of the surface protection layer. On the other hand, when the influence of other layers (for example, the base sheet) of the decorative sheet cannot be ignored, it is preferable to measure the martensitic hardness with only the surface protection layer as the measurement object.

[0070] As an example of the method for forming the surface protection layer, a method of coating a resin composition containing a polyurethane resin can be mentioned. As the coating method, the same coating methods as those for the barrier layer described above can be mentioned. Also, a curing treatment may be performed on the uncured resin layer (uncured surface protection layer) after coating. As the curing treatment, for example, heat treatment and ionizing radiation irradiation treatment can be mentioned.

[0071] The heat treatment temperature is not particularly limited as long as the desired curing reaction occurs. For example, it may be 50°C or higher, 70°C or higher, or 80°C or higher. On the other hand, the upper limit of the heat treatment temperature can be appropriately selected according to the types of the resin composition and the curing agent. The heat treatment method is not particularly limited, and a general heat treatment method can be adopted.

[0072] The ionization radiation irradiation treatment is a treatment for curing a coated uncured resin layer by irradiating it with ionization radiation such as electron beams and ultraviolet rays. When using electron beams as the ionization radiation, the acceleration voltage is not particularly limited. For example, it is 70 kV or higher and 300 kV or lower. Also, the irradiation dose is not particularly limited. For example, it is 5 kGy or higher and 300 kGy or lower. On the other hand, when using ultraviolet rays as the ionization radiation, it is preferable to use ultraviolet rays with a wavelength of 190 nm or longer and 380 nm or shorter, for example.

[0073] The surface protective layer may contain various additives as required. Examples of the additives include weather resistance improvers, abrasion resistance improvers, polymerization inhibitors, crosslinking agents, infrared absorbers, antistatic agents, adhesion improvers, leveling agents, thixotropy imparting agents, coupling agents, plasticizers, defoaming agents, fillers, solvents, and colorants. Note that the content of the additives can be appropriately set according to the purpose.

[0074] Examples of the weather resistance improvers include ultraviolet absorbers and light stabilizers. The ultraviolet absorber can be either inorganic or organic. Examples of the inorganic ultraviolet absorbers include titanium dioxide, cerium oxide, and zinc oxide. On the other hand, examples of the organic ultraviolet absorbers include benzotriazole-based ultraviolet absorbers. Also, examples of the light stabilizers include hindered amine-based light stabilizers.

[0075] The wear resistance improver preferably has, for example, a particulate shape. Also, the wear resistance improver may be either inorganic or organic. Examples of the inorganic wear resistance improver include α-alumina, silica, kaolinite, iron oxide, diamond, and silicon carbide. On the other hand, examples of the organic wear resistance improver include crosslinked acrylic resin and polycarbonate resin.

[0076] The thickness of the surface protective layer is, for example, 2 μm or more, and may be 4 μm or more, or may be 6 μm or more. If the thickness is too small, the function as a protective layer may be reduced. On the other hand, the thickness of the surface protective layer is, for example, 100 μm or less, and may be 60 μm or less, or may be 30 μm or less. If the thickness is too large, the three-dimensional moldability may be reduced.

[0077] Also, the surface protective layer preferably has a large elongation at break. This is because the three-dimensional moldability is improved. The elongation at break of the surface protective layer in a tensile test at 150 °C is, for example, 120% or more, and may be 150% or more, or may be 200% or more. On the other hand, the elongation at break of the surface protective layer in a tensile test at 150 °C is not particularly limited, but is, for example, 500% or less. The elongation at break of the surface protective layer can be measured, for example, as follows, either as a decorative sheet or as a single layer of the surface protective layer.

[0078] The elongation at break of the surface protective layer in the decorative sheet can be measured under the conditions conforming to JIS K 7127 as follows. First, cut out the decorative sheet into a test piece with a width of 25 mm and a length of 120 mm. Next, for this test piece, measure the tensile elongation until cracks occur in the surface protective layer under the measurement conditions of a tensile speed of 1000 mm / min, a chuck distance of 80 mm, a gauge distance of 50 mm, and a temperature of 160 °C. For example, when a thermosetting resin is used for the surface protective layer and a thermoplastic resin is used for the other layers, generally, the layer using the thermoplastic resin has a larger elongation at break than the layer using the thermosetting resin. Therefore, it is easy to determine that the cracks generated in the measurement of the elongation at break of the decorative sheet are derived from the surface protective layer.

[0079] The elongation at break of the single-layer surface protective layer can be measured under the conditions conforming to JIS K 7127 as follows. First, cut out a transfer sheet with the surface protective layer formed on the surface into a width of 25 mm and a length of 120 mm, and peel off the transfer sheet to obtain a test piece. Next, for this test piece, under the measurement conditions of a tensile speed of 1000 mm / min, a chuck distance of 80 mm, a gauge distance of 50 mm, and a temperature of 160°C, measure the tensile elongation until cracks appear in the surface protective layer.

[0080] 3. Substrate sheet The substrate sheet in the present disclosure contains a resin. The resin used for the substrate sheet is preferably a thermoplastic resin. Examples of the thermoplastic resin include acrylonitrile-butadiene-styrene resin (ABS resin); acrylic resin; polyolefin resins such as polypropylene and polyethylene; polycarbonate resin; vinyl chloride resin. In addition, these resins may be used alone or in combination of two or more. Further, the substrate sheet may be a single-layer sheet or a multi-layer sheet.

[0081] The thickness of the substrate sheet varies depending on the application, but is, for example, 0.05 mm or more, and may be 0.1 mm or more. On the other hand, the thickness of the substrate sheet is, for example, 1.0 mm or less, and may be 0.7 mm or less.

[0082] At least one surface of the substrate sheet may be surface-treated. By surface-treating, for example, the adhesion between the substrate sheet and other layers can be improved. Examples of the surface treatment method include an oxidation method and a roughening method. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone-ultraviolet treatment method. Examples of the roughening method include sandblasting method and solvent treatment method. In addition, the substrate sheet may be provided with decorativeness such as painting or patterns. Note that at least one surface of not only the substrate sheet but also each layer constituting the decorative sheet may be surface-treated. This is because the adhesion between layers can be improved.

[0083] 4. Pattern layer The decorative sheet in the present disclosure may have a pattern layer. By providing the pattern layer, the decorative sheet can be easily imparted with decorativeness. The pattern layer is preferably located between the base sheet and the barrier layer.

[0084] Examples of the pattern of the pattern layer include, for example, a wood grain pattern; a stone grain pattern imitating the surface of a rock such as a marble pattern (for example, a travertine marble pattern); a fabric pattern imitating a cloth texture or a cloth-like pattern; a tile sticker pattern; a brick stack pattern. In addition, a marquetry or patchwork combining these patterns may be used. Also, the pattern of the pattern layer may be a plain color without a pattern.

[0085] The pattern layer preferably contains a colorant and a binder. Examples of the colorant include, for example, inorganic pigments such as carbon black (ink), iron black, titanium white, antimony white, lead yellow, titanium yellow, safflower, cadmium red, ultramarine blue, cobalt blue; organic pigments or dyes such as quinacridone red, isoindolinone yellow, phthalocyanine blue; metal pigments such as aluminum and brass; pearlescent (pearl) pigments such as titanium dioxide-coated mica and basic lead carbonate.

[0086] Examples of the binder include, for example, polyurethane resin, vinyl chloride / vinyl acetate copolymer resin, vinyl chloride / vinyl acetate / acrylic copolymer resin, chlorinated polypropylene resin, acrylic resin, polyester resin, polyamide resin, butyral resin, polystyrene resin, nitrocellulose resin, and cellulose acetate resin.

[0087] In addition, the pattern layer may contain additives such as extender pigments, solvents, stabilizers, plasticizers, catalysts, and curing agents. The thickness of the pattern layer is, for example, 1 μm or more and 20 μm or less. Examples of the method for forming the pattern layer include general printing methods such as the gravure printing method.

[0088] The decorative sheet in the present disclosure may have a concealment layer between the base material sheet and the pattern layer. By providing the concealment layer, for example, it is possible to suppress the color of the base material sheet from affecting the pattern layer. The color of the concealment layer is preferably an opaque color. Further, the concealment layer is preferably a so-called solid layer.

[0089] 5. Primer layer The decorative sheet of the present disclosure may have a primer layer. By providing the primer layer, for example, even when the surface protection layer is stretched, it is possible to suppress the occurrence of fine cracks and whitening in the surface protection layer. The primer layer is preferably located between the base material sheet and the barrier layer. Further, when the decorative sheet has a pattern layer, the primer layer is preferably located between the pattern layer and the barrier layer.

[0090] The primer layer preferably contains a resin. Examples of such resins include, for example, (meth)acrylic resins, urethane resins, (meth)acrylic-urethane copolymer resins, vinyl chloride-vinyl acetate copolymer resins, polyester resins, butyral resins, chlorinated polypropylene, and chlorinated polyethylene. In addition, these resins may be used alone or in combination of two or more. Further, in this specification, (meth)acrylic means acrylic or methacrylic.

[0091] Examples of the (meth)acrylic resin include homopolymers of (meth)acrylic acid esters, copolymers of two or more different (meth)acrylic acid ester monomers, and copolymers of (meth)acrylic acid esters and other monomers. Specific examples of the (meth)acrylic resin include poly(methyl (meth)acrylate), poly(ethyl (meth)acrylate), poly(propyl (meth)acrylate), poly(butyl (meth)acrylate), methyl (meth)acrylate-butyl (meth)acrylate copolymer, ethyl (meth)acrylate-butyl (meth)acrylate copolymer, ethylene-methyl (meth)acrylate copolymer, and styrene-methyl (meth)acrylate copolymer.

[0092] Examples of the urethane resin include polyurethane having a polyol (polyhydric alcohol) as the main component and an isocyanate as the crosslinking agent (curing agent). The polyol has two or more hydroxyl groups in the molecule. Examples of the polyol include polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, and polyether polyol. On the other hand, examples of the isocyanate include polyvalent isocyanates having two or more isocyanate groups in the molecule; aromatic isocyanates such as 4,4-diphenylmethane diisocyanate; aliphatic (or alicyclic) isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Further, the primer layer may contain a butyral resin in addition to the urethane resin.

[0093] Examples of the (meth)acrylic-urethane copolymer resin include acrylic / urethane (polyester urethane) block copolymer resins. As the curing agent, the various isocyanates described above can be used. The acrylic / urethane ratio (mass ratio) in the acrylic / urethane (polyester urethane) block copolymer resin is, for example, (9 / 1) or more and (1 / 9) or less, and may be (8 / 2) or more and (2 / 8) or less.

[0094] The thickness of the primer layer is, for example, 0.1 μm or more, and may be 1 μm or more. On the other hand, the thickness of the primer layer is, for example, 10 μm or less. Examples of the method for forming the primer layer include general coating methods such as gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, and reverse roll coating.

[0095] 6. Adhesive layer Further, the decorative sheet in the present disclosure may have an adhesive layer at a position on the side opposite to the surface protective layer with respect to the base material sheet. By providing the adhesive layer, the adhesion between the decorative sheet and the resin molded product is improved.

[0096] The adhesive layer preferably contains a resin. Examples of the resin used for the adhesive layer include thermoplastic resins and thermosetting resins. Examples of the thermoplastic resin include acrylic resins, acrylic-modified polyolefin resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymers, thermoplastic urethane resins, thermoplastic polyester resins, polyamide resins, and rubber-based resins. Examples of the thermosetting resin include urethane resins and epoxy resins. Note that these resins may be used alone or in combination of two or more.

[0097] The thickness of the adhesive layer is, for example, 0.1 μm or more, and may be 1 μm or more. On the other hand, the thickness of the adhesive layer is, for example, 10 μm or less. The method for forming the adhesive layer is not particularly limited, and general coating methods can be mentioned.

[0098] 7. Decorative sheet The decorative sheet in the present disclosure has at least a base material sheet, a barrier layer, and a surface protection layer in this order, and may further have at least one of a pattern layer, a primer layer, and an adhesive layer.

[0099] Also, in the present disclosure, it is possible to provide a method for manufacturing the above-described decorative sheet. That is, it is possible to provide a method for manufacturing a decorative sheet having a barrier layer forming step for forming the barrier layer and a surface protection layer forming step for forming the surface protection layer, which is the above-described method for manufacturing a decorative sheet.

[0100] Also, the decorative sheet in the present disclosure is preferably used for manufacturing (particularly three-dimensional molding) of a decorative resin molded article. Details of the decorative resin molded article will be described later.

[0101] B. Decorative resin molded article The decorative resin molded article in the present disclosure has a resin molded article and a decorative sheet located on the surface of the resin molded article.

[0102] According to the present disclosure, by using the above-described decorative sheet, a decorative resin molded article having a barrier layer with good solid fragrance resistance and adhesion can be obtained.

[0103] The decorative sheet in the present disclosure is the same as the content described in the above "A. Decorative Sheet", so the description here is omitted. The decorative sheet in the decorative resin molded article is usually formed so as to follow the shape of at least a part of the outer surface of the resin molded article. Further, the decorative sheet in the decorative resin molded article is usually integrated with the resin molded article. Also, in the decorative sheet of the decorative resin molded article, the surface protective layer is usually located on the outside and the base material sheet is located on the inside.

[0104] The resin molded article in the present disclosure preferably has at least one of, for example, a curved surface portion, a bent portion, and a flat portion. The resin used for the resin molded article may be a thermoplastic resin or a thermosetting resin.

[0105] Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, acrylonitrile-butadiene-styrene resin (ABS resin), styrene resin, polycarbonate resin, acrylic resin, and vinyl chloride resin. On the other hand, examples of the thermosetting resin include urethane resin and epoxy resin. These resins may be used alone or in combination of two or more.

[0106] Examples of the method for manufacturing the decorative resin molded article in the present disclosure include injection molding methods such as insert molding method, injection molding simultaneous decoration method, blow molding method, and gas injection molding method.

[0107] For example, in the insert molding method, in the vacuum molding process, the decorative sheet is preformed into the surface shape of the molded product by a vacuum molding die (offline preforming), and then the excess portion is trimmed as necessary to obtain a molded sheet. This molded sheet is inserted into an injection molding die, the injection molding die is clamped, and the resin in a fluid state is injected into the die and solidified, so that the decorative sheet is integrated with the outer surface of the resin molded product simultaneously with the injection molding. Thereby, a decorated resin molded product is obtained.

[0108] Also, for example, in the simultaneous injection molding and decoration method, the decorative sheet is placed in a female die that also serves as a vacuum molding die provided with suction holes for injection molding, and preforming (inline preforming) is performed using this female die. Then, the injection molding die is clamped, and the resin in a fluid state is injected into the die and solidified, so that the decorative sheet is integrated with the outer surface of the resin molded article simultaneously with the injection molding. Thereby, a decorated resin molded product is obtained.

[0109] In addition, the decorated resin molded product in the present disclosure can also be produced by a decoration method in which a decorative sheet is adhered onto a previously prepared three-dimensional resin molded product, such as a vacuum pressure bonding method. In the vacuum pressure bonding method, first, the decorative sheet and the resin molded product are placed in a vacuum pressure bonding machine having a first vacuum chamber located on the upper side and a second vacuum chamber located on the lower side, such that the decorative sheet is on the first vacuum chamber side and the resin molded product is on the second vacuum chamber side, and the base sheet of the decorative sheet faces the resin molded product side, and the two vacuum chambers are brought into a vacuum state. The resin molded product is placed on a lift table provided in the second vacuum chamber and capable of moving up and down. Next, the first vacuum chamber is pressurized, and the resin molded product is pressed against the decorative sheet using the lift table, and the decorative sheet is adhered to the surface of the resin molded product while stretching the decorative sheet by utilizing the pressure difference between the two vacuum chambers. Finally, the two vacuum chambers are opened to the atmosphere, and if necessary, the excess portion of the decorative sheet is trimmed to obtain a decorated resin molded product. In the vacuum pressure bonding method, it is preferable to include a step of heating the decorative sheet before the step of pressing the resin molded product against the decorative sheet in order to soften the decorative sheet and improve its formability. Such a vacuum pressure bonding method including such a step is sometimes particularly called a vacuum heat pressure bonding method.

[0110] Examples of the uses of the decorated resin molded article in the present disclosure include, for example, interior or exterior materials for vehicles such as automobiles; fittings such as window frames and door frames; interior materials for building materials such as walls, floors, and ceilings; housings for household appliances such as television receivers and air conditioners; and containers.

[0111] Note that the present disclosure is not limited to the above embodiments. The above embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits the same operational effects is included in the technical scope of the present disclosure in any case.

Example

[0112] [Example 1] An ABS resin film (flexural modulus of elasticity: 2000 MPa, thickness: 400 μm) was prepared as the base sheet. Next, a woodgrain pattern layer was formed on the surface of the base sheet by gravure printing using an ink containing an acrylic resin as a binder. In this way, a first member having the base sheet and the pattern layer was obtained.

[0113] Next, as the polyurethane resin for forming the surface protective layer, an aqueous polyurethane resin dispersion 1 was prepared as follows. First, 65.00 parts by mass of polycarbonate polyol (manufactured by Asahi Kasei Corporation, trade name "Duranol T-4671", containing 1,4-butanediol and 1,6-hexanediol as raw materials; repeating unit: 1,4-butanediol / 1,6-hexanediol = 7 / 3 (molar ratio), hydroxyl value = 112.2 mgKOH / g, number average molecular weight = 1000), 5.00 parts by mass of dimethylolpropionic acid, and 100 parts by mass of methyl ethyl ketone were added to a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen blowing tube, and stirred and dissolved thoroughly. Then, 30.00 parts by mass of dicyclohexylmethane diisocyanate was added and reacted at 75°C until the NCO content reached 1.00%. After that, the prepolymer solution was cooled to 45°C, 3.77 parts by mass of triethylamine as a neutralizing agent was added, and 400.00 parts by mass of water was gradually added and emulsified and dispersed using a homomixer. Then, 0.65 parts by mass of diethylenetriamine was added, and the chain extension reaction was carried out at 30°C for 30 minutes. This resin solution was heated under reduced pressure to distill off methyl ethyl ketone, and an aqueous polyurethane resin dispersion 1 with a solid content of 25% was obtained.

[0114] A resin composition containing 100 parts by mass of the aqueous polyurethane resin dispersion 1 and 5 parts by mass of a carbodiimide-based curing agent (V-02-L2 manufactured by Nisshinbo Chemical Co., Ltd., solid content 40% by mass) was prepared. Next, the prepared resin composition was coated on one side of a polyethylene terephthalate sheet as a transfer substrate to form an uncured surface protective layer. By heating the uncured surface protective layer under the conditions of 100°C for 5 minutes, a surface protective layer (thickness after curing: 10 μm) was formed.

[0115] Next, polyvinyl alcohol-polyurethane hybrid resin 1 was prepared as a hybrid resin of a polyvinyl alcohol-based resin and a polyurethane resin for forming a barrier layer as follows. First, water was put into a beaker equipped with a stirrer, and polyvinyl alcohol (PVA1: Gosenex Z series (Z-200) manufactured by Mitsubishi Chemical Corporation, an acetacetyl group-modified polyvinyl alcohol) was added while stirring at room temperature. After confirming that PVA was uniformly dispersed in water, the solution was gradually heated to 95° C. to completely dissolve PVA. Then, an aqueous polyvinyl alcohol solution 1 was obtained by slowly cooling it to room temperature. Next, the aqueous polyvinyl alcohol solution 1 and an aqueous urethane resin dispersion 1 were put into a beaker equipped with a stirrer so that the solid content ratio was polyvinyl alcohol:aqueous urethane resin dispersion 1 = 7:3. The mixture was stirred until the liquid became uniform to obtain polyvinyl alcohol-polyurethane hybrid resin 1.

[0116] Next, the prepared polyvinyl alcohol-polyurethane hybrid resin 1 was applied to the surface of the surface protective layer to form an uncured barrier layer. The uncured barrier layer was heated under the conditions of 120° C. for 5 minutes to form a barrier layer (thickness after curing: 5 μm). In this way, a second member having a transfer base material, a surface protective layer, and a barrier layer in this order was obtained.

[0117] A composition containing acrylic polyol and hexamethylene diisocyanate was applied to the surface of the obtained second member to form a primer layer. The first member and the second member were arranged so that the pattern layer in the first member and the barrier layer in the second member faced each other via the primer layer. Then, the transfer base material was peeled off from the second member to obtain a decorative sheet.

[0118] [Examples 2 to 8] A decorative sheet was obtained in the same manner as in Example 1, except that the coating amount and composition of the composition for forming the barrier layer were changed as shown in Table 1. In Table 1, PVA2 is N-type and A-type Gosenol (N-300) manufactured by Mitsubishi Chemical Corporation, which is polyvinyl alcohol; PVA3 is Nichigo G Polymer (OKS-1109) manufactured by Mitsubishi Chemical Corporation, which is polyvinyl alcohol having a 1,2-glycol bond; PVA4 is D Polymer (DF-17) manufactured by Nippon Vinyl Acetate & Poval Co., Ltd., which is diacetone-modified polyvinyl alcohol; EVOH is Eversorb #10 manufactured by Nippon Seima Co., Ltd.

[0119] [Example 9] On one side of the transfer substrate of Example 1, the prepared polyvinyl alcohol-polyurethane mixed resin 1 was coated to form an uncured barrier layer. The uncured barrier layer was heated under the conditions of 120 °C for 5 minutes to form a barrier layer (thickness after curing: 5 μm). In this way, a third member having a transfer substrate and a barrier layer in this order was obtained.

[0120] A composition containing acrylic polyol and hexamethylene diisocyanate was coated on the surface of the obtained third member (barrier layer surface) to form a primer layer. The first member and the third member were arranged so that the pattern layer in the first member of Example 1 and the barrier layer in the third member faced each other through the primer layer. Then, the transfer substrate was peeled off from the third member. In this way, a fourth member having a base sheet (ABS resin film), a pattern layer, a primer layer, and a barrier layer in this order was obtained.

[0121] Next, a bifunctional urethane acrylate (weight average molecular weight: 20,000) having a polycarbonate skeleton was coated on the barrier layer of the fourth member to form an uncured surface protection layer. The uncured surface protection layer was irradiated with an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) to form a surface protection layer (thickness after curing: 10 μm). In this way, a decorative sheet was obtained.

[0122] [Example 10] A decorative sheet was obtained in the same manner as in Example 1, except that the coating amount and composition of the composition for forming the barrier layer were changed as shown in Table 1, and the uncured barrier layer was heated at 120°C for 2 minutes.

[0123] [Example 11] A decorative sheet was obtained in the same manner as in Example 1, except that the coating amount and composition of the composition for forming the barrier layer were changed as shown in Table 1.

[0124] [Comparative Example 1] A decorative sheet was produced in the same manner as in Example 1, except that a vinyl alcohol-based resin was not used in the barrier layer.

[0125] [Comparative Examples 2 - 6] A decorative sheet was produced in the same manner as in Example 1, Examples 5 - 8, respectively, except that a polyurethane resin was not used in the barrier layer.

[0126] [Evaluation] (Solid air freshener resistance) On the decorative sheets obtained in each example and each comparative example, a solid air freshener cut to a predetermined size was placed, and it was heated at 70°C for 4 hours while applying a load of 400 g. Then, the solid air freshener was removed, and after wiping the surface with a wipe, the appearance was visually observed. The criteria for judgment were as follows. The results are shown in Table 1 and Table 2. The solid air freshener is a commercially available product containing mainly piperonal, vanillin, asarone, rosin, benzyl benzoate, and dipropylene glycol as aromatic components. 5: No trace 4: Slight trace on the coating film 3: Trace on the coating film 2: The base of the base sheet is exposed 1: The solid air freshener cannot be removed from the base sheet in an adhesive state

[0127] (Adhesion test) The adhesiveness of the decorative sheets obtained in each Example and Comparative Example was evaluated in accordance with the cross-cut test of JIS K 5400. Specifically, 11 cuts were made vertically and horizontally at 1 mm intervals on the surface of the decorative sheet facing the surface protection layer, creating 100 1 mm grids, and cellophane tape (manufactured by Nichiban Co., Ltd.) was applied on top of the cuts and quickly peeled off at a 90° angle. The adhesiveness was evaluated based on the state of the cross-cut surface. The evaluation criteria were as follows: 5: No peeling 4: Peeling occurs outside the grid 3: Minor peeling occurs within the grid 2: Peeling occurs in about 50% of the grid. 1: Complete peeling

[0128] (Three-dimensional formability) The decorative sheets obtained in each example and comparative example were subjected to vacuum forming to evaluate their three-dimensional formability. Specifically, the decorative sheets were heated to 160°C using an infrared heater and softened. Next, vacuum forming was performed using a vacuum forming mold (maximum stretch ratio 250%) to mold the sheet to fit the internal shape of the mold. After cooling, the decorative sheet was released from the mold. The appearance of the surface protective layer of the decorative sheet after release was evaluated. The evaluation criteria are as follows: 3: No peeling or other defects were observed. 2: Slight defects such as peeling were observed. 1: Defects such as peeling were clearly observed.

[0129] (sunscreen resistant) The sunscreen resistance of the decorated sheets obtained in Examples 1 to 3, 5 to 7 and Comparative Examples 1 to 5 was evaluated. Specifically, 50 mg of a commercially available sunscreen cosmetic (sunscreen cream) was uniformly applied to a portion of the surface of the decorated sheet measuring 10 mm in length and 10 mm in width. An aluminum plate was placed so as to cover the applied portion, and while applying a load of 400 g, it was left in an oven at 60 °C for 1 hour. Next, the decorated sheet was taken out, the surface was washed away with a neutral detergent solution, and the state of the applied portion was visually observed, and the chemical resistance of the decorated sheet was evaluated according to the following criteria. The sunscreen cosmetic used was a commercially available product, and as components, it contained 2-ethylhexyl salicylate, homosalate, octocrylene, and phenoxyethanol, and had high erosivity on the resin surface. The evaluation criteria are as follows. Note that if the evaluation is 3 or more, it can be evaluated that it has sunscreen resistance. Also, a hyphen (-) represents non-evaluation. 5: No traces were seen on the coating film. 4: Almost no traces were seen on the coating film. 3: Slight traces were seen on the coating film. 2: Traces were prominently seen in the form of a coating film. 1: The substrate of the base sheet was exposed.

[0130] (Infrared spectroscopic analysis) Regarding the barrier layer of the decorated sheet obtained in each example, an infrared absorption spectrum (IR spectrum) was measured. The barrier layer was exposed on the surface by scraping and removing the surface protective layer of the decorated sheet with a cutter knife. As the IR spectrum device, FT / IR6100 manufactured by JASCO Corporation was used. The IR spectrum measurement was performed by the total reflection method (ATR method). The results of a representative example (Example 3) are shown in Fig. 2. Also, in the columns of "Presence or absence of crystalline peak (IR)" in Tables 1 and 2, the presence or absence of a peak associated with the crystallization of the vinyl alcohol-based resin is shown.

[0131]

Table 1

[0132]

Table 2

[0133] As shown in Table 1 and Table 2, it was confirmed that the barrier layer containing a vinyl alcohol-based resin exhibits good solid fragrance resistance. As shown in Figure 2, this is presumably because a peak can be confirmed at 1141 cm -1 due to the crystallization of polyvinyl alcohol. Also, as shown in Example 10, even when no distinct peak can be confirmed at 1141 cm -1 in the infrared absorption spectrum, it is assumed that the polyvinyl alcohol has a structure approximating that of a crystal, and it was confirmed that sufficient barrier properties can be provided by adjusting the film thickness of the barrier layer. Furthermore, in each example, since the barrier layer contains a polyurethane resin, the adhesion and moldability were also good. Also, the surface protective layer in the decorative sheet of each example all had a Martens hardness of 40 N / mm 2 or less.

[0134] Furthermore, Examples 1 to 3 and 7 had higher sunburn resistance than Examples 5 to 6. This is presumably because Examples 1 to 3 and 7 used PVA1 or 4 having a hydrophobic group other than an acetic acid group as the vinyl alcohol-based resin, and the hydrophobicity of the barrier layer was high.

Explanation of Reference Numerals

[0135] 1... Substrate sheet 2... Pattern layer 3... Primer layer 4... Barrier layer 5... Surface protective layer 10... Decorative sheet

Claims

1. A decorative sheet located on the surface of a resin molded article for decorating the resin molded article, wherein the decorative sheet has at least a base material sheet, a barrier layer, and a surface protection layer in this order, and the barrier layer contains a vinyl alcohol-based resin and a polyurethane resin, in the decorated resin molded article in which the decorative sheet and the resin molded article are integrated, the surface protection layer is located on the outermost surface, at least one layer in direct contact with the barrier layer contains a polyurethane resin, the decorative sheet is a decorative sheet used when manufacturing the decorated resin molded article by an injection molding method or a vacuum pressure bonding method.

2. The barrier layer has a peak in the infrared absorption spectrum in the range of 1130 cm －１ or more and 1160 cm －１ or less. The decorated sheet according to claim 1.

3. The decorative sheet according to claim 1 or claim 2, wherein in the barrier layer, the proportion of the polyurethane resin with respect to the total of the vinyl alcohol-based resin and the polyurethane resin is 5% by mass or more and 40% by mass or less.

4. The decorative sheet according to any one of claims 1 to 3, wherein the vinyl alcohol-based resin is a modified polyvinyl alcohol resin having a hydrophobic group other than an acetic acid group.

5. The decorative sheet according to claim 4, wherein the hydrophobic group has a reactive group.

6. The decorative sheet according to claim 5, wherein the reactive group is a reactive carbonyl group.

7. The decorative sheet according to claim 6, wherein the modified polyvinyl alcohol resin has an acetoacetyl group having the reactive carbonyl group as the hydrophobic group.

8. The decorative sheet according to any one of claims 1 to 7, wherein the surface protection layer includes a cured product of a resin composition.

9. The decorative sheet according to any one of claims 1 to 8, wherein the surface protection layer contains a polyurethane resin.

10. The surface protective layer has a Martens hardness of 40 N / mm ２ The decorated sheet according to any one of claims 1 to 9, wherein the Martens hardness is 40 N / mm or less.

11. The decorative sheet according to any one of claims 1 to 10, wherein the elongation at break of the surface protection layer is 120% or more.

12. The decorative sheet according to any one of claims 1 to 11, wherein the surface protection layer and the barrier layer are in direct contact.

13. The decorative sheet according to any one of claims 1 to 12, wherein a pattern layer is disposed between the base material sheet and the barrier layer.

14. A decorated resin molded article having a resin molded article and a decorative sheet located on the surface of the resin molded article, The decorative sheet has at least a base material sheet, a barrier layer, and a surface protection layer in this order from the resin molded product side. The barrier layer contains a vinyl alcohol-based resin and a polyurethane resin. At least one layer in direct contact with the barrier layer contains a polyurethane resin. The decorated resin molded product is a decorated resin molded product in which the decorative sheet and the resin molded product are integrated by an injection molding method or a vacuum pressure bonding method.

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