JP7544229B2 - Laminate and decorative sheet using same - Google Patents

Description

The present invention relates to resin laminates such as resin films, and decorative sheets using the same for use in architectural interior materials, architectural exterior components such as entrance doors, surfaces of building fixtures, and surface materials for home appliances.

In recent years, many decorative sheets using olefin resins have been proposed as alternatives to polyvinyl chloride decorative sheets. These decorative sheets are used to protect architectural interior materials for houses and public facilities, architectural exterior materials such as entrance doors, surfaces of fixtures, and surface materials of home appliances. For this reason, they are exposed to direct sunlight and wind and rain every day, and therefore require extremely high weather resistance. (See Patent Document 1)
The decorative sheets described in Patent Document 1 all aim to improve weather resistance by incorporating light stabilizers, ultraviolet absorbers, etc. into the protective layer or coating layer. However, it is known that with long-term use, the light stabilizers and ultraviolet absorbers are lost due to bleeding out from the olefin resin or coating surface, and the chemical structure of each material is destroyed by oxygen or light, causing loss of function.

Patent No. 4032829

However, when a target layer such as a protective layer or a coating layer contains an ultraviolet absorber or a light stabilizer in an amount sufficient to provide sufficient weather resistance, aggregation of the ultraviolet absorber or light stabilizer may occur in the resin composition constituting each layer.
Furthermore, when the chemical structures of the ultraviolet absorber and the light stabilizer in the resin composition are broken down and become low molecular weight, the decomposed components of the ultraviolet absorber and the light stabilizer tend to rise out from the surface of each layer, which is called bleed-out. This leads to a decrease in adhesion to other layers, and the components rise to the surface, causing problems such as stickiness.

The present invention was developed with the above points in mind, and aims to provide a decorative sheet with stable weather resistance.

The inventors have conducted various investigations into conditions that prevent the decomposition of the UV absorber and light stabilizer over time and enable use over a long period of time without deterioration in quality, and have found suitable conditions for the top coat layer.
In order to solve the problems, a laminate according to one embodiment of the present invention is a laminate consisting of a plurality of resin layers, characterized in that a top coat layer located on the outermost surface side of the laminate contains a light stabilizer having a pKa of 4.0 to 7.0.

According to one aspect of the present invention, by using the above laminate, it is possible to provide a decorative sheet that has stable weather resistance over a long period of time.

FIG. 1 is a cross-sectional view illustrating a laminate according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.
Here, the configuration shown in Fig. 1 is schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each layer, etc. differ from the actual ones. Furthermore, the embodiments shown below are examples of configurations for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited to the materials, shapes, structures, etc. of the components described below. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims.

As shown in FIG. 1, the decorative sheet 1 of this embodiment is configured by arranging an ink layer 5, an adhesive layer 4, a transparent resin layer 3 as a surface protection layer, and a topcoat layer 2 in this order on a raw fabric layer 6 that constitutes a base material layer. An embossed pattern 3a that constitutes a concave-convex pattern is formed on the upper surface of the transparent resin layer 3. The concave-convex pattern may be formed by a method other than embossing. The transparent resin layer 3 is configured from an olefin resin layer. In the example of FIG. 1, an adhesive resin layer 7 is provided between the transparent resin layer 3 and the adhesive layer 4 to improve adhesion, but the adhesive resin layer 7 may not be provided.

This decorative sheet 1 is produced, for example, by forming an adhesive layer 4 on an original resin sheet having an ink layer 5 formed on one side of an original layer 6 to form a first laminate, and by forming a topcoat layer 2 containing a light stabilizer and a gloss adjuster on a resin sheet having a transparent resin layer 3 and an adhesive resin layer 7 co-extruded thereon to form a second laminate, and then bonding the first laminate and the second laminate together by dry lamination, extrusion lamination, or the like.
The details of each layer are described below.

<Topcoat layer>
A topcoat layer 2, which plays a role in protecting the surface and adjusting the luster, is provided on the outermost layer of the decorative sheet 1. At least a light stabilizer is blended in the topcoat layer 2. In addition to the light stabilizer, the topcoat layer 2 preferably also contains an ultraviolet absorbing agent.
Furthermore, the top coat layer 2 of this embodiment contains inorganic particles as a gloss adjuster.

Here, in FIG. 1, the topcoat layer 2 is formed on the entire surface of the transparent resin layer 3 along the surface of the transparent resin layer 3, but is not limited thereto. The topcoat layer 2 may be embedded by wiping the recesses of the embossed pattern 3a formed in the transparent resin layer 3 by applying a resin composition to the recesses and scraping off the coating liquid with a squeegee or the like, thereby embedding the resin composition only in the recesses. The surface of the topcoat layer 2 may be flat, regardless of the recesses of the embossed pattern 3a. The topcoat layer 2 only needs to be embedded in at least the recesses of the embossed pattern 3a, and the embedded topcoat layer 2 can maintain high weather resistance even in the recesses where the layer thickness is thinned by forming the embossed pattern 3a. By providing the topcoat layer 2 so as to cover the entire surface of the transparent resin layer 3, a decorative sheet 1 with better weather resistance can be provided.

(Resin material)
The resin material as the main component of the topcoat layer 2 can be appropriately selected from polyurethane, acrylic silicone, fluorine, epoxy, vinyl, polyester, melamine, aminoalkyd, urea, and other resin materials. The form of the resin material is not particularly limited, and may be water-based, emulsion, solvent-based, or the like. The curing method may also be appropriately selected from one-liquid type, two-liquid type, ultraviolet curing method, and the like.
In this specification, the term "main component" refers to a resin material that is contained in 70% by mass or more, and preferably 90% by mass or more, of the material that constitutes the target layer.

As the resin material used as the main component of the topcoat layer 2, a urethane-based resin using isocyanate is suitable from the viewpoints of workability, cost, and the cohesive strength of the resin itself. The isocyanate can be appropriately selected from curing agents such as adducts, biuret, and isocyanurates, which are derivatives of tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), bis(isocyanatomethyl)cyclohexane (HXDI), and trimethylhexamethylene diisocyanate (TMDI). However, in consideration of weather resistance, a curing agent based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI), which have a linear molecular structure, is suitable.

In addition, when trying to improve the surface hardness, it is preferable to use a resin that is cured by active energy rays such as ultraviolet rays or electron beams. As the main material, various monomers, commercially available oligomers, and other known materials can be used, but it is preferable to use polyfunctional monomers such as pentaerythritol triacrylate (PET3A), pentaerythritol tetraacrylate (PET4A), trimethylolpropane triacrylate (TMPTA), dipentaerythritol hexaacrylate (DPHA), polyfunctional oligomers such as Shiko UV-1700B (manufactured by Nippon Synthetic Chemical Industry), or mixtures of these.

These resins can be used in combination with one another. For example, a hybrid type of a thermosetting resin and a photocurable resin can be used, which can improve surface hardness, suppress shrinkage upon curing, and improve adhesion.
In this case, the topcoat layer 2 may be composed of multiple layers, for example, two layers: a heat-cured layer mainly made of a heat-cured resin, and a photo-cured layer mainly made of a photo-cured resin such as an ultraviolet-cured resin. By constructing the topcoat layer from two cured layers in this way, the surface hardness of the decorative sheet 1 can be improved. In this case, it is preferable that the photo-cured layer is on the surface layer side.

(Light stabilizer)
In this embodiment, the top coat layer 2 contains a light stabilizer having a pKa of 4.0 or more and 7.0 or less. When the top coat layer 2 is a multi-layered layer, it is preferable that each layer contains a light stabilizer having a pKa of 4.0 or more and 7.0 or less, but it is sufficient that at least one layer constituting the top coat layer 2 contains a light stabilizer having a pKa of 4.0 or more and 7.0 or less.
The light stabilizer is preferably a hindered amine light stabilizer, and more preferably a hindered amine light stabilizer having an amino ether group and a molecular weight of 600 or more. The molecular weight of the light stabilizer may be measured, for example, in terms of number average molecular weight.

The method for measuring the number average molecular weight of the light stabilizer is not particularly limited, but it is preferable to use gel permeation chromatography. The GPC measurement device is not particularly limited, but it is preferable to use polystyrene gel as the packing material of the GPC column and tetrahydrofuran (THF) as the eluent. In addition, polystyrene polymer may be used as the standard substance for GPC.
However, when the light stabilizer is composed of a single substance, and the structure is known, the molecular weight of the light stabilizer may be calculated from the structural formula.
The light stabilizer is, for example, the following hindered amine compound (1), which can capture radicals through the reaction of reaction formula (2).

Hindered amine light stabilizers include bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate; bis(2,2,6,6-tetramethylpiperidin-4-yl)succinate; bis(1,2,2,6,6-pentamethylpiperidin-4-yl)sebacate; bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate; bis(1,2,2,6,6-pentamethylpiperidin-4-yl)n-butyl 3,5-di-tert -butyl 4-hydroxybenzyl malonate; 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid condensate; 2,2,6,6-tetramethylpiperidin-4-yl stearate; 2,2,6,6-tetramethylpiperidin-4-yl dodecane; 1,2,2,6,6-pentamethylpiperidin-4-yl stearate; 1,2,2,6,6-pentamethylpiperidin-4-yl dodecane; N,N'-bis(2, 2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine condensate; tris(2,2,6,6-tetramethylpiperidin-4-yl)nitrilotriacetate; tetrakis(2,2,6,6-tetramethylpiperidin-4-yl)-1,2,3,4-butanetetracarboxylate; 4-benzoyl-2,2,6,6-tetramethylpiperidine; 4-stearyloxy-2 ,2,6,6-tetramethylpiperidine; bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl 2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate; 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione; bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate; bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl) Succinate; Condensation product of N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-morpholino 2,6-dichloro-1,3,5-triazine; Condensation product of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane; Condensation product of 2-chloro-4,6-bis(4-n-butylamino-1,2,2,6,6-pentamethyl piperidyl)-1,3,5-triazine and condensation product of 1,2-bis-(3-aminopropylamino)ethane; 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione; 3-dodecyl-1-(2,2,6,6-tetramethylpiperidin-4-yl)pyrrolidine-2,5-dione; 3-dodecyl-1-(1-ethanoyl-2,2,6,6-tetramethylpiperidin-4-yl)pyrrolidine-2,5-dione 3-dodecyl-1-(1,2,2,6,6-pentamethylpiperidin-4-yl)pyrrolidine-2,5-dione; a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine; a condensation product of N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine; 1,2-bis(3-aminopropylamino)ethane, 2 , condensation product of 4,6-trichloro-1,3,5-triazine and 4-butylamino-2,2,6,6-tetramethylpiperidine; 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxospiro[4.5]decane; oxo-piperandinyl-triazine; reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro[4.5]decane and epichlorohydrin.

In addition, N-alkoxy hindered amine light stabilizers include tetrakis(2,2,6,6-tetramethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate; 1,2,3,4-butanetetracarboxylic acid tetrakis(1,2,2,6,6-pentamethyl-4-piperidinyl)ester; 1,2,3,4-butanetetracarboxylic acid 1,2,2,6,6-pentamethyl-4-piperidinyl tridecyl ester; 1,2,3,4-butanetetracarboxylic acid 2,2,6,6-tetramethyl-4-piperidinyl tridecyl ester; 1,2,3,4-butanetetracarboxylic acid 2,2,6,6-tetramethyl-4-piperidinyl tridecyl ester; Examples include 1,2,2,6,6-pentamethyl-4-piperidinyl ester of a polymer of tetracarboxylic acid and 2,2,6,6-tetramethyl-2,4,8,10-tetraoxaspiro[5.5]-undecane-3,9-diethanol; 2,2,6,6-tetramethyl-4-piperidinyl ester of a polymer of 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-2,4,8,10-tetraoxaspiro[5.5]-undecane-3,9-diethanol; and bis(1-undecaneoxy-2,2,6,6-tetramethylpiperidin-4-yl) carbonate.

Hydroxyl-substituted N-alkoxy HALS include 1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethyl-4-piperidinol; 1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine; 1-(4-octadecanoyloxy-2,2,6,6-tetramethylpiperidin-1-yloxy)-2-octadecanoyloxy-2-methylpropane; 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol; and reaction products of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol and dimethyl succinate.

Among these hindered amine-based light stabilizers, representative commercially available ones include, for example, Tinuvin 123, Tinuvin 152, Tinuvin NOR 371 FF, Tinuvin XT850 FF, Tinuvin XT855 FF, TINUVIN 5100, TINUVIN 622SF, Flamestab NOR 116 FF, and Adeka STAB LA-81, manufactured by ADEKA Corp. These may be used alone or in combination of two or more kinds.
When a light stabilizer is blended in the topcoat layer 2, it is preferable to blend 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the resin of the layer to be blended. More preferably, it is 0.3 parts by mass or more and 3.0 parts by mass or less. If the blending amount of the light stabilizer is less than 0.1 parts by mass, the effect of stabilizing the resin against generated radicals may be low. On the other hand, if it is more than 5.0 parts by mass, there is a high possibility that bleeding out will occur.

(Ultraviolet absorber)
When an ultraviolet absorber is blended in the top coat layer 2, it is preferable to blend an ultraviolet absorber having a pKa of −4.5 to −5.5 when irradiated with light. Here, when the top coat layer 2 is made up of multiple layers, it is preferable to blend an ultraviolet absorber having a pKa of −4.5 to −5.5 when irradiated with light in each layer.
When the UV absorber is blended in the topcoat layer 2, it is preferably blended in an amount of 1.0 part by mass or more and 15.0 parts by mass or less per 100 parts by mass of the resin of the layer to be blended. More preferably, it is blended in an amount of 2.5 parts by mass or more and 8.0 parts by mass or less. If the blending amount of the UV absorber is less than 1.0 part by mass, the effect of stabilizing the resin against UV rays may be low. On the other hand, if it is more than 15.0 parts by mass, there is a high possibility that bleeding out may occur.

When the top coat layer 2 has a thermosetting layer and a photocurable layer as described above, it is preferable to blend a larger amount of the ultraviolet absorbing agent on the thermosetting layer side.
The ultraviolet absorbing agent may be selected from at least one of benzotriazoles, triazines, benzophenones, benzoates, and cyanoacrylates.
In particular, organic ultraviolet absorbers of benzotriazole or triazine have high ultraviolet absorbing power, and are excellent in heat resistance, volatility resistance and resin compatibility, so it is preferable to select and use at least one of them.Furthermore, it is preferable that the ultraviolet absorber has a triazine skeleton or a benzotriazole skeleton and has a molecular weight of 400 or more.The molecular weight of the ultraviolet absorber may be calculated from its structural formula, or may be the number average molecular weight measured by a known method.

The ultraviolet absorber is a compound (3) having a hydroxyphenyltriazine skeleton or a compound (4) having a benzotriazole skeleton, and these are preferably compounds having a maximum absorption at 270 nm to 400 nm. The ultraviolet absorbers described above are excited by absorbing light, and depending on the skeleton, hydrogen atoms move within the molecule. They can return to the ground state by releasing heat. These can be shown by reaction formulas (5) and (6), respectively.

Examples of compounds having the above hydroxyphenyltriazine skeleton include 2-(2-hydroxy-4-octoxyphenyl)-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4,6-diphenyl-s-triazine, 2-(2-hydroxy-4-propoxy-5-methylphenyl)-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-[2-hydroxy-4-(3-dodecylphenyl)-s-triazine, 2-[2-hydroxy-4-[3-(2-ethylhexyloxy)-2-hydroxypropyloxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-[2-hydroxy-4-[3-(2-ethylhexyloxy)-2-hydroxypropyloxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-[2-hydroxy-4-[3-(2-ethylhexyloxy)-2-hydroxypropyloxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4,6-diviphenyl-s-triazine, 2-[2-hydroxy-4-[1-(i-octyloxycarbonyl)ethyloxy]phenyl]-4,6-diviphenyl-s-triazine, 2,4-bis(2-hydroxy-4-octoxyphenyl)-6-(2,4-dimethylphenyl)-s-triazine, 2,4-bis(4-butoxy-2-hydroxyphenyl)-6-(2,4-dibutoxyf phenyl)-s-triazine, 2,4,6-tris(2-hydroxy-4-octoxyphenyl)-s-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine (product name CYASORB (registered trademark) UV-1164), and 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine (product name LA-F70).

Examples of compounds having the benzotriazole skeleton include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-(2-(octyloxycarbonyl)ethyl)phenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-dodecyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole, bis(2-(2'-hydroxy-3',5'-di-(dimethylbenzyl)phenyl)benzotriazole, 2-(2'-hydroxy-4'-octyloxyphenyl)benzotriazole, 2,2'-methylene-bis(2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-3'-(3,4,5,6-tetrahydrophthalimidylmethyl)-5'-methylbenzyl)phenyl)benzotriazole, 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol (trade name LA-36), 2-(5-chloro-2-benzotriazolyl)-6-tert-butyl-p-cresol (trade name Tinuvin (registered trademark) 326), etc.

Benzotriazole-based UV absorbers include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-dicumylphenyl)benzotriazole, and 2,2'-methylenebis(4-tert-octyl-6-benzotriazolyl)phenol.

Examples of triazine-based UV absorbers include 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, and 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-( 2,4-dibutoxyphenyl)-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-[(2-hydroxy-3-(2'-ethyl)hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, etc.

Benzophenone-based ultraviolet absorbents include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5'-methylenebis(2-hydroxy-4-methoxybenzophenone).
Benzoate-based ultraviolet absorbers include phenyl salicylate, resorcinol monobenzoate, 2,4-di-tert-butylphenyl-3',5'-di-tert-butyl-4'-hydroxybenzoate, 2,4-di-tert-amylphenyl-3',5'-di-tert-butyl-4'-hydroxybenzoate, and hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate.
Examples of cyanoacrylate-based ultraviolet absorbents include ethyl-α-cyano-β,β-diphenylacrylate, and methyl-2-cyano-3-methyl-3-(p-methoxyphenyl)acrylate.

(Gloss adjuster)
The topcoat layer 2 contains inorganic particles as a gloss regulator. Examples of inorganic particles include silica, clay, calcium carbonate, barium sulfate, alumina white, aluminum hydroxide, talc, bentonite, titanium oxide, etc., white carbon such as silicic anhydride, hydrated silicic acid, calcium silicate hydrate, and aluminum silicate hydrate, which are known as colloidal silica, and alumina sol. In addition, surface modification with polydimethylsiloxane, polyethylene wax, a surfactant, etc. is preferable because it improves dispersibility and contamination resistance.

The particle size of the inorganic particles is preferably 1 μm or more and 20 μm or less, and more preferably 3 μm or more and 10 μm or less. If the particle size is smaller than 1 μm, the effect of adjusting the gloss may be low. On the other hand, if the particle size is larger than 20 μm, the filler is more likely to be chipped off from the coating surface.
The pH of the inorganic particles to be blended is desirably near neutral, ie, greater than 5.0 and less than 8.5. If inorganic particles having a pH of less than 5.0 or greater than 8.5 are used, there is a possibility that by-products will be generated due to the pKa of the light stabilizer.
The inorganic particles contribute to the design (glossiness) of the decorative sheet, so an appropriate amount is blended (added) accordingly. The blending amount of the inorganic particles may be 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the resin that is the main component of the top coat layer 2.

<Transparent resin layer>
The transparent resin layer 3 constitutes the base material of the topcoat layer 2, and when the ink layer 5 is provided, it serves as a protective layer that protects the ink layer 5. The transparency of the transparent resin layer 3 needs to be sufficient to allow the ink layer 5 to be visually recognized. Note that the laminate needs to include at least the transparent resin layer 3 and the topcoat layer 2. When the ink layer 5 is not provided, the transparent resin layer 3 does not need to be transparent.
The transparent resin layer 3 is preferably a resin layer whose main component is an olefin resin and which contains 0.3 parts by mass or more of a compound having a pKa of 7.0 or less per 100 parts by mass of the resin material. The compound having a pKa of 7.0 or less is preferably 15.0 parts by mass or less.
The compound having a pKa of 7.0 or less is, for example, the same light stabilizer or ultraviolet absorber as that blended in the top coat layer 2 as described above.

In the transparent resin layer 3 of this embodiment, an embossed pattern is formed as shown in FIG.
The embossed pattern 3a is formed to improve design. The embossed pattern 3a can be formed by a method of forming the embossed pattern 3a by applying heat and pressure using an embossing plate having a concave-convex pattern before forming the topcoat layer 2, or by a method of forming the embossed pattern 3a simultaneously with cooling the sheet using a cooling roll having a concave-convex pattern when forming a film using an extruder.

The resin material used as the main component of the transparent resin layer 3 is preferably made of an olefin-based resin, and in addition to polypropylene, polyethylene, polybutene, etc., α-olefins (e.g., propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, Examples of the copolymer include a homopolymer or copolymer of two or more of α-olefins (e.g., 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.), and copolymers of ethylene or α-olefins with other monomers, such as ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate copolymer. In addition, when improving the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene.

In addition, the resin composition constituting the transparent resin layer 3 may contain various functional additives such as a heat stabilizer, a light stabilizer, an antiblocking agent, a catalyst trap, a colorant, a light scattering agent, and a gloss adjuster, if necessary. These various functional additives can be appropriately selected from well-known additives.
When non-polar polypropylene is used for the transparent resin layer 3, if the adhesion between the transparent resin layer 3 and the resin layer disposed on the lower surface is low, it is preferable to provide an adhesive resin layer 7. The adhesive resin layer 7 is preferably an acid-modified resin such as polypropylene, polyethylene, or acrylic resin, and the layer thickness is preferably 2 μm or more and 20 μm or less from the viewpoint of adhesiveness and heat resistance. Moreover, the adhesive resin layer 7 is preferably formed by co-extrusion lamination with the transparent resin layer 3 from the viewpoint of improving adhesive strength.

<Ink layer and adhesive layer>
As shown in FIG. 1, an adhesive layer 4 is provided on the lower surface side of the transparent resin layer 3 in order to improve adhesion between the lower ink layer 5 and the transparent resin layer 3 .
The material of the adhesive layer 4 is not particularly limited, but may be appropriately selected from acrylic, polyester, polyurethane, epoxy, etc. The coating method may be appropriately selected depending on the viscosity of the adhesive, but generally, gravure coating is used, and the adhesive is applied by gravure coating to the original fabric layer 6 side on which the ink layer 5 is applied, and then laminated with the transparent resin layer 3 and the adhesive resin layer 7. The adhesive layer 4 may be omitted if sufficient adhesive strength is obtained between the transparent resin layer 3 and the ink layer 5.

An ink layer 5 is provided on the lower surface side of the adhesive layer 4. The ink layer 5 preferably contains at least a light stabilizer. As the light stabilizer, a hindered amine-based material is preferably used. By including a light stabilizer in the ink layer 5, it is possible to suppress fading of the pigment caused by radicals generated by deterioration of the binder resin itself forming the ink layer 5 or the resins of other layers, which reduce the chemical components of the pigment in the ink, and therefore it is possible to maintain a colorful image for a long period of time.
The ink layer 5 of this embodiment includes a picture pattern layer 5a and a solid ink layer 5b. At least the picture pattern layer 5a contains a light stabilizer for the above-mentioned purpose. By providing the solid ink layer 5b on the lower surface side of the picture pattern layer 5a, it is possible to provide hiding power.

For the ink of the picture pattern layer 5a, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, etc., may be used as a binder, or may be selected from modified products of each of these. The binder is not particularly limited to aqueous, solvent-based, emulsion-based, etc., and the curing method may be a one-liquid type or a two-liquid type using a curing agent. Furthermore, a method of curing the ink by irradiation with active energy rays such as ultraviolet rays or electron beams may be used. In particular, a common method is to use a urethane-based ink and cure it with isocyanate. In addition to these binders, pigments contained in ordinary inks, colorants such as dyes, extender pigments, solvents, various additives, etc. are contained. Examples of pigments with high versatility include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and pearls such as mica.

The solid ink layer 5b can basically be made of the same material as the ink used in the picture pattern layer 5a, but if the ink is transparent, opaque pigments, iron oxide, titanium oxide, etc. can be used. In addition, it is possible to impart hiding power by blending metals such as silver, copper, and aluminum. Generally, flake aluminum is used. The solid ink layer 5b does not have to be provided.
These ink layers 5 can be formed directly on the base layer 6 by gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, inkjet printing, etc. When the concealing property is imparted by a metal, it is preferable to use a comma coater, a knife coater, a lip coater, metal vapor deposition, a sputtering method, or the like.
In addition, for the interface where the resin material or ink is laminated, taking into consideration the adhesiveness, the surface to be laminated can be activated by performing a surface treatment such as corona treatment, ozone treatment, plasma treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment before applying the resin material or ink, and then the lamination process can be performed, thereby improving the adhesiveness between the layers.

<Original layer>
An original fabric layer 6 serving as a base layer is provided on the lower surface side of the ink layer 5. The original fabric layer 6 can be arbitrarily selected from paper such as tissue paper, titanium paper, and resin-impregnated paper, synthetic resins such as polyethylene, polypropylene, polystyrene, polybutylene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and acrylic, or foams of these synthetic resins, rubbers such as ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene-styrene block copolymer rubber, and polyurethane, organic or inorganic nonwoven fabrics, synthetic paper, and metal foils such as aluminum, iron, gold, and silver.

In addition, when an olefin-based resin is used as the raw fabric layer 6, since the surface is often in an inactive state, it is preferable to provide a primer layer (not shown) between the raw fabric layer 6 and the substrate (not shown) to which the decorative sheet 1 is attached. In addition, in order to improve the adhesion between the raw fabric layer 6 made of an olefin-based resin and the substrate, it is preferable that the back surface of the raw fabric layer 6 is subjected to corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromate treatment, or the like.
The primer layer can be made of the same material as the ink layer 5. However, taking into consideration that the decorative sheet 1 will be rolled up in web form, it is preferable for the primer layer to contain an inorganic filler such as silica, alumina, magnesia, titanium oxide or barium sulfate in order to avoid blocking and to improve adhesion to the adhesive.
In the decorative sheet 1 of this embodiment, taking into consideration printing workability, cost, etc., it is desirable that the base layer 6 be 20 μm to 150 μm, the adhesive layer 4 be 1 μm to 20 μm, the transparent resin layer 3 be 20 μm to 200 μm, and the top coat layer 2 be 3 μm to 20 μm, and it is preferable that the total thickness of the decorative sheet 1 be in the range of 45 μm to 400 μm.

<About action and other details>
Since UV absorbers and light stabilizers require intermolecular interactions, it is preferable for them to be in close proximity. Here, we will look at the interaction when a UV absorber with a triazine or benzotriazole skeleton is used with a light stabilizer with a hindered amine skeleton. In general, the intermolecular interaction between a UV absorber and a light stabilizer occurs between the conjugated system of the UV absorber and the hindered amine skeleton of the light stabilizer. When a UV absorber absorbs light, there is a high probability that an intramolecular hydrogen bond is formed on the nitrogen of the triazine or benzotriazole skeleton. In other words, the hydrogen on the hydroxyl group is in a state that is easily dissociated.

And, by coexisting with a light stabilizer having a pKa of more than 7.0, the ultraviolet absorber in an excited state after absorbing light is more likely to undergo a side reaction through an acid-base reaction with the light stabilizer. In other words, the ultraviolet absorber and light stabilizer cannot undergo the reactions of reaction formula (2), reaction formula (5), and reaction formula (6) that would normally occur, and the side reactions increase. In other words, they are more likely to be decomposed by light, leading to a decrease in weather resistance. On the other hand, when a light stabilizer having a pKa of 7.0 or less is used, the ultraviolet absorber and light stabilizer are less likely to undergo an acid-base reaction with the hydrogen on the hydroxyl group of the ultraviolet absorber in an excited state after absorbing light, and therefore the ultraviolet absorber and light stabilizer are more likely to undergo the reactions of reaction formula (2), reaction formula (5), and reaction formula (6). As a result, weather resistance against light can be improved.

In view of this, in this embodiment, a light stabilizer having a pKa of 4.0 to 7.0 is blended into the resin composition constituting the top coat layer 2, thereby making it possible to provide a laminate or decorative sheet 1 having stable weather resistance over a long period of time.
In addition, as in this embodiment, by containing a light stabilizer having a pKa of 4.0 to 7.0 in the resin composition of the top coat layer 2, it is possible to prevent a decrease in weather resistance caused by blending inorganic particles as a gloss regulator in the top coat layer 2. This is because, when the pKa of the light stabilizer is greater than 7.0, the vicinity of the top coat layer 2 in contact with the inorganic particle surface is more likely to undergo a side reaction due to an acid-base reaction, and the proportion of the light stabilizer in the top coat layer 2 is more likely to decrease. Therefore, it is preferable to use a light stabilizer having a pKa of 7.0 or less as the light stabilizer to be blended in the top coat layer 2.

In addition, as in this embodiment, by including a light stabilizer with a pKa of 4.0 to 7.0 in the resin composition of the topcoat layer 2, it is possible to prevent a decrease in weather resistance when residual monomers derived from raw materials are present in the topcoat layer 2. This is because when the pKa of the light stabilizer is greater than 7.0, side reactions are more likely to occur due to acid-base reactions in the vicinity of the residual monomers, and the proportion of light stabilizer in the topcoat layer 2 is more likely to decrease. For this reason, it is preferable to use a light stabilizer with a pKa of 7.0 or less.

(Method for measuring pKa of light stabilizer)
A 0.1N perchloric acid/dioxane solution of acetonitrile:chloroform=1:1 was dropped onto an organic reference material having a known pKa value in an aqueous system, and the half-neutralization potential (HNP) in a non-aqueous system was titrated. At that time, a plot of a HNP calibration curve against pKa was created. Then, a light stabilizer was titrated in the same manner, and the corresponding pKa was obtained from the calibration curve plot.

(Method for measuring pKa of ultraviolet absorber when absorbing light)
Here, the ultraviolet absorber was dissolved in acetonitrile so that the absorbance at the maximum absorption wavelength was 1, and nitrogen was bubbled for 15 minutes. Then, 70% perchloric acid was dropped into this solution to change the pH of the solution. At that time, the absorption spectrum of the solution was measured, and the ultraviolet absorber at each pH and the nitrogen of the benzotriazole skeleton or triazine skeleton of the ultraviolet absorber with hydrogen ions added thereto were calculated from the absorbance at λmax. The pKa of the ultraviolet absorber at the time of light absorption was obtained from the point where the values were equal. A Hitachi High-Tech U-4000 spectrophotometer was used to measure the absorption spectrum.

(Method for Measuring pH of Silica Particles)
Measurements were performed according to JIS. First, 200 g of purified water was added to 10 g of silica particles that had been dried for 2 hours at 170°C in air, and the mixture was covered with a watch glass. After that, the mixture was heated and stirred at 80±3°C for 1 hour, cooled to room temperature, and the supernatant was collected. After the supernatant was cooled to 25°C, it was measured using an analog pH meter HM-7J (manufactured by DKK Toa Corporation) conforming to JIS Z8802.

Specific examples of the laminate and decorative sheet according to the present invention will be described below.
Example 1
A resin containing 100 parts by mass of a highly crystalline homopolypropylene resin, 0.5 parts by mass of a hindered phenol-based antioxidant (Irganox 1010; manufactured by BASF), 0.5 parts by mass of a triazine-based ultraviolet absorber (CYASORB UV-1164; manufactured by SUNCHEM), and 0.5 parts by mass of a NOR-type light stabilizer (Tinuvin XT850 FF; manufactured by BASF) was melt-extruded using an extruder to form a sheet-like transparent resin layer 3 as a transparent highly crystalline polypropylene sheet having a thickness of 100 μm. Then, both sides of the obtained transparent resin layer 3 were subjected to a corona treatment, and the wetting tension of the sheet surface was set to 40 dyn/cm or more.

On the other hand, a picture was printed on one side of an 80 μm thick polyethylene sheet (raw material layer 6) with concealing properties by gravure printing using a two-component urethane ink (V180; manufactured by Toyo Ink Co., Ltd.) to form a picture pattern layer 5a, and a primer coating was applied to the other side of the raw material layer 6.
Thereafter, a transparent resin layer 3 was laminated by a dry lamination method onto the surface of the picture pattern layer 5a of the raw sheet layer 6 via a dry lamination adhesive (Takelac A540; manufactured by Mitsui Chemicals, Inc.; coating amount 2 g/ ^m2 ). An embossed pattern 3a was formed on the surface of the transparent resin layer 3 of this laminated sheet.
The following composition for forming a topcoat layer was applied to the transparent resin layer 3 having the embossed pattern 3a at a coating thickness of ³ g/m2 and dried to form a topcoat layer 2, thereby obtaining the decorative sheet 1 of Example 1 having a total thickness of 185 μm.

(Topcoat layer A forming composition)
The composition for forming the top coat layer A was prepared by blending the following polymer solution A with the following curing agent, gloss regulator, ultraviolet absorber, and light stabilizer.
Polymer solution A
In a four-neck flask equipped with a stirrer, a nitrogen inlet tube, and a reflux condenser, 80 g of methyl methacrylate and 20 g of 2-hydroxyethyl methacrylate were introduced, 70 g of ethyl acetate was added to dissolve, and the mixture was stirred in a nitrogen atmosphere on an oil bath. Polymerization was initiated by adding 0.2 g of α,α'-azobisisobutyronitrile to the mixture, and the mixture was heated and stirred for 5 hours on a 60°C oil bath to obtain a colorless, viscous polymer solution A.
・Hardening agent Product name: Duranate 24A-100
Blended: 5 parts by weight gloss regulator (inorganic particles)
Product name: P-801 (Mizusawa Industrial Chemicals)
Properties: irregular shape, average particle size 6.0 μm, pH 6.8
Blend: 10 parts by weight UV absorber Product name: Tinuvin 329 (manufactured by BASF)
Formulation: 2.5 parts by weight Light stabilizer Product name: Tinuvin 123 (manufactured by BASF)
Blending ratio: 1.5 parts by weight

Example 2
A decorative sheet 1 of Example 2 was obtained in the same manner as in Example 1, except that the gloss regulator in Example 1 was replaced with C-402 (Mizusawa Industrial Chemicals).
Example 3
A decorative sheet 1 of Example 3 was obtained in the same manner as in Example 1, except that the gloss regulator in Example 1 was replaced with NP-8 (Mizusawa Industrial Chemicals).

Example 4
A decorative sheet 1 of Example 4 was obtained in the same manner as in Example 1, except that the type of light stabilizer used in Example 1 was changed to Tinuvin 152 (manufactured by BASF).
Example 5
A decorative sheet 1 of Example 5 was obtained in the same manner as in Example 2, except that the type of light stabilizer used in Example 2 was changed to Tinuvin 152 (manufactured by BASF).

Example 6
A decorative sheet 1 of Example 6 was obtained in the same manner as in Example 3, except that the type of light stabilizer used in Example 3 was changed to Tinuvin 152 (manufactured by BASF).
Example 7
A decorative sheet 1 of Example 7 was obtained in the same manner as in Example 1, except that the blending amount of the light stabilizer in Example 1 was changed to 0.5 parts by mass.

Example 8
A decorative sheet 1 of Example 8 was obtained in the same manner as in Example 1, except that the blending amount of the light stabilizer in Example 1 was changed to 3.0 parts by mass.
<Example 9>
A decorative sheet 1 of Example 9 was obtained in the same manner as in Example 1, except that the blending amount of the light stabilizer in Example 1 was changed to 15.0 parts by mass.

<Comparative Examples 1 to 3>
Decorative sheets 1 of Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the light stabilizer in Examples 1 to 3 was replaced with Tinuvin 292 (manufactured by BASF).
<Comparative Example 4>
A decorative sheet 1 of Comparative Example 4 was obtained in the same manner as in Example 1, except that the light stabilizer of Example 1 was not blended.

The light stabilizers and gloss adjusters used are shown in Table 1. Table 1 also lists the evaluation results.

In addition, using Example 1 as a base, the decorative sheets of Examples 10 to 18 below were prepared by changing the top coat layer.
Example 10
A decorative sheet of Example 10 was obtained, which was made of a top coat layer B obtained by changing the top coat layer-forming composition of Example 1 as follows.
(Topcoat layer B forming composition)
The composition for forming the top coat layer B was prepared by blending the following resin liquid A with the following initiator, gloss regulator, ultraviolet absorber, and light stabilizer.
Resin liquid A
Product name: M405 (Toagosei)
Initiator Product name: Irgcure 184 (manufactured by BASF)
Blending: 5 parts by weight Gloss regulator (inorganic particles) Same as in Example 1 UV absorber Same as in Example 1 Light stabilizer Same as in Example 1

Example 11
A topcoat layer C was coated on the topcoat layer A of Example 1 in the same manner as in Example 1, except that the polymer solution A in Example 1 was replaced with the polymer solution B, to obtain a two-layer decorative sheet of Example 11. The method for preparing the polymer solution B is described below.
Polymer solution B
In a four-neck flask equipped with a stirrer, a nitrogen inlet tube, and a reflux condenser, 50 g of methyl methacrylate and 50 g of 2-hydroxyethyl methacrylate were introduced, 70 g of ethyl acetate was added to dissolve, and the mixture was stirred in a nitrogen atmosphere on an oil bath. Polymerization was initiated by adding 0.2 g of α,α'-azobisisobutyronitrile to the mixture, and the mixture was heated and stirred for 5 hours on a 60°C oil bath to obtain a colorless, viscous polymer solution B.

Example 12
The topcoat layer B used in Example 10 was applied onto the topcoat layer A of Example 1 to obtain a decorative sheet of Example 12 consisting of two layers.

Example 13
A decorative sheet of Example 13 was obtained, which was made of a top coat layer D obtained by changing the top coat layer-forming composition of Example 1 as follows.
(Topcoat layer D forming composition)
The composition for forming the top coat layer D was prepared by blending the following resin liquid B with the following curing agent, initiator, gloss regulator, ultraviolet absorber, and light stabilizer.
Resin liquid B
Polymer liquid A and resin liquid A were mixed in an amount of 50 parts by mass each to obtain resin liquid B.
Initiator Product name: Irgcure 184 (manufactured by BASF)
Formulation: 5 parts by weight Hardener Product name: Duranate 24A-100
Blending: 5 parts by weight Gloss regulator (inorganic particles) Same as in Example 1 UV absorber Same as in Example 1 Light stabilizer Same as in Example 1

<Example 14>
The topcoat layer D used in Example 13 was applied onto the topcoat layer A of Example 1 to obtain a decorative sheet of Example 14 consisting of two layers.

Example 15
A topcoat layer E was formed on the topcoat layer D of Example 13 by coating the topcoat layer-forming composition of Example 13 with the following modifications, to obtain a two-layer decorative sheet of Example 15.
(Topcoat layer E forming composition)
The composition for forming the top coat layer E was prepared by blending the following resin liquid C with the following curing agent, initiator, gloss regulator, ultraviolet absorber, and light stabilizer.
Resin liquid C
Resin liquid C was obtained by blending 20 parts by mass of polymer liquid B and 80 parts by mass of resin liquid A.
Initiator: Same as in Example 10. Hardener: Same as in Example 10. Gloss adjuster (inorganic particles): Same as in Example 1. UV absorber: Same as in Example 1. Light stabilizer: Same as in Example 1.

<Example 16>
The topcoat layer B used in Example 10 was coated on the topcoat layer D of Example 13 to obtain a decorative sheet of Example 16 consisting of two layers.
<Example 17>
The coats used in Examples 13 and 10 were laminated in this order on the top coat layer of Example 1 to obtain a decorative sheet of Example 17 consisting of three layers.
<Example 18>
The coating used in Example 10 was applied onto the topcoat layer of Example 11 to obtain a decorative sheet of Example 18 consisting of three layers.

The layer structures of the topcoat layers, the light stabilizers and the gloss regulators used in Examples 1 and 10 to 18 are shown in Table 2. Table 2 also shows the evaluation results.
In the layer structure, "heat" refers to a heat-curable layer, "UV" refers to a photocurable layer, and "UV/heat" refers to a mixed layer of photocurable resin and heat-curable resin.

<Evaluation>
(Weather resistance (appearance))
The decorative sheets obtained in the examples and comparative examples were set in a metal weatherer manufactured by Daipla Wintes Co., Ltd. and left for 20 hours under light conditions (illuminance: 60 mW/ ^cm2 , black panel temperature 63°C, intralayer humidity 50% RH), 4 hours under condensation conditions (illuminance: 0 mW/ ^cm2 , black panel temperature 30°C, intralayer humidity 98% RH), and 500 or 1000 hours under water spray conditions (10 seconds before and after condensation conditions). After the above tests, the sheets were kept for 2 days under conditions of 25°C and 50% RH, and then the appearance of the sheet surface, such as cracks and yellowing, was visually evaluated according to the following criteria.

(Coating appearance)
○: No change in appearance was observed.
△: Fine cracks were observed on the surface.
×: Numerous cracks were present on the surface.
(Yellowing of the substrate)
○: No change in appearance was observed.
△: Some yellowing was observed.
×: Significant yellowing.

In the decorative sheets of each embodiment, as shown in Table 1, by combining light stabilizers with pKa values of 4.0 to 7.0 and blending them into the resin, it was possible to produce decorative sheets that were less susceptible to changes in appearance and that could suppress changes in gloss after weather resistance testing without producing haze.
As can be seen from Tables 1 and 2, when a light stabilizer having a pKa value of more than 7.0 was blended into the surface protective layer, both the coating appearance and the yellowing of the substrate were worse than when a light stabilizer having a pKa value of 4.0 to 7.0 was used. In addition, when 15.0 parts by mass of the light stabilizer was blended, haze occurred in the coating film at the time of preparation, but no change in appearance or yellowing of the resin was observed before and after the weather resistance test. This is because the ultraviolet absorber and light stabilizer bled out onto the surface protective layer, increasing the haze value, but it is believed that the performance was demonstrated because sufficient weather resistance agent was included.

From the above results, it is apparent that the decorative sheet 1 of the embodiment based on the present invention has excellent weather resistance.
The decorative sheet 1 of the present invention is not limited to the above-mentioned embodiment and examples, and various modifications are possible without impairing the characteristics of the invention.

1 Decorative sheet 2 Topcoat layer 3 Transparent resin layer 3a Embossed pattern 4 Adhesive layer 5 Ink layer 5a Picture pattern layer 5b Solid ink layer 6 Base layer (substrate layer)
7 Adhesive resin layer

Claims (9)

A laminate consisting of a plurality of resin layers,
the top coat layer located on the outermost surface side of the laminate contains a light stabilizer having a pKa of 4.0 to 7.0;
The topcoat layer includes a thermosetting layer and a mixed layer formed on the thermosetting layer and containing a thermosetting resin and a photocurable resin;
A laminate , wherein the thermosetting resin in the mixed layer is a resin containing methyl methacrylate and 2-hydroxyethyl methacrylate as constituent components . The laminate described in claim 1, characterized in that the light stabilizer is a hindered amine light stabilizer. The laminate according to claim 1 or 2, characterized in that the topcoat layer contains a gloss adjuster made of inorganic particles. the thermosetting layer and the mixed layer each contain the gloss control agent,
The laminate described in claim 3, characterized in that the content of the gloss adjuster per 100 parts by mass of the main component resin of the thermosetting layer is the same as the content of the gloss adjuster per 100 parts by mass of the main component resin of the mixed layer. 5. The laminate according to claim 3, wherein the inorganic particles have a pH value of more than 5.0 and not more than 8.5 when dispersed. 6. The laminate according to claim 3, wherein the gloss control agent is polydimethylsiloxane, polyethylene wax, or inorganic particles whose surfaces are modified with a surfactant. The main component of the resin is an olefin resin layer, and the olefin resin layer contains 0.3 parts by mass or more of a compound having a pKa of 7.0 or less per 100 parts by mass of the resin material,
7. The laminate according to claim 1, wherein the top coat layer is formed on the olefin resin layer. 8. The laminate according to claim 1, wherein the thermosetting resin constituting the thermosetting layer is a resin containing methyl methacrylate and 2 -hydroxyethyl methacrylate as constituent components. A decorative sheet comprising the laminate according to any one of claims 1 to 8 .

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