JP7589446B2 - Decorative sheet and decorative material using same - Google Patents

Description

The present invention relates to a decorative sheet and a decorative material using the same.

Traditionally, decorative sheets have been used to decorate and protect the interior and exterior components of buildings, or the surfaces of furniture, fixtures, home appliances, etc. Decorative sheets have a configuration that includes, for example, a surface protection layer on a substrate.

When these decorative sheets are used outdoors or indoors near a window where they are exposed to sunlight, the effects of ultraviolet rays can cause color changes and deterioration of the resin. For this reason, ultraviolet absorbers are added to the surface protective layer of the decorative sheets to improve their weather resistance.

However, there is a problem in that the UV absorber tends to bleed out (also called "bleed out" or "migrate") from the surface protective layer over time. When the UV absorber bleeds out, the aesthetic appearance of the decorative sheet surface is impaired, and the concentration of the UV absorber in the surface protective layer decreases over time, resulting in insufficient weather resistance. To solve the problem of UV absorber bleeding, for example, Patent Document 1 has been proposed.

JP 2000-117905 A

The decorative sheet of Patent Document 1 contains an electron beam reactive ultraviolet absorber selected from specific benzotriazole-based compounds in a cured layer of a resin whose main component is an electron beam curable resin. The decorative sheet of Patent Document 1 can solve the problem of ultraviolet absorber bleeding out.

On the other hand, decorative sheets are often required to be suitable for processing, such as embossing, folding, and molding, and in recent years, decorative sheets have been proposed in which a layer containing a polypropylene-based resin, which has excellent processing suitability, is laminated and then a surface protective layer is laminated thereon. When the surface protective layer of Patent Document 1 is applied to such a decorative sheet formed by laminating layers containing a polypropylene-based resin, there have been many cases in which deterioration over time of the decorative sheet due to ultraviolet rays cannot be suppressed even if the bleed-out of the ultraviolet absorber in the surface protective layer is suppressed.

The present invention was made under these circumstances, and aims to suppress deterioration over time due to ultraviolet rays in a decorative sheet formed by laminating layers containing polypropylene-based resins, and in a decorative material using the same.

In order to solve the above problems, the present invention provides the following [1] and [2].
[1] A decorative sheet having, in this order, a surface protective layer, a transparent resin layer containing a polypropylene-based resin, and a base layer containing a polypropylene-based resin, wherein the surface protective layer has an absorbance A1 of 0.6 or more at a wavelength of 270 to 300 nm, measured in accordance with JIS K0115:2004, and the surface protective layer and the transparent resin layer have an absorbance A2 of 1.2 or more at a wavelength of 270 to 300 nm, measured in accordance with JIS K0115:2004. [2] A decorative material having an adherend and the decorative sheet according to [1] above.

According to the present invention, deterioration over time caused by ultraviolet rays can be suppressed in a decorative sheet formed by laminating layers containing a polypropylene-based resin.

1 is a cross-sectional view showing one embodiment of a decorative sheet of the present invention.

[Decorative sheet]
The decorative sheet of the present invention has a surface protective layer, a transparent resin layer containing a polypropylene-based resin, and a base layer containing a polypropylene-based resin, in this order, and the surface protective layer has an absorbance A1 of 0.6 or more at a wavelength of 270 to 300 nm, measured in accordance with JIS K0115:2004, and the surface protective layer and the transparent resin layer have an absorbance A2 of 1.2 or more at a wavelength of 270 to 300 nm, measured in accordance with JIS K0115:2004.

In this specification, "absorbance A1 of the surface protective layer at wavelengths of 270 to 300 nm, measured in accordance with JIS K0115:2004" may be referred to as "absorbance A1," and "absorbance A2 of the surface protective layer and transparent resin layer at wavelengths of 270 to 300 nm, measured in accordance with JIS K0115:2004" may be referred to as "absorbance A2." In addition, in this specification, "transparent resin layer containing polypropylene-based resin" may be referred to as "transparent resin layer," and "substrate layer containing polypropylene-based resin" may be referred to as "substrate layer." In addition, in this specification, the notation "AA to BB" means "AA or more and BB or less," unless otherwise specified.

FIG. 1 is a cross-sectional view showing an embodiment of a decorative sheet 100 of the present invention.
The decorative sheet 100 in Fig. 1 has, in this order, a surface protective layer 10, a transparent resin layer 20 containing a polypropylene-based resin, and a base layer 40 containing a polypropylene-based resin. The surface protective layer 10 of the decorative sheet 100 in Fig. 1 is composed of a top coat layer 11 and a primer layer 12. The decorative sheet 100 in Fig. 1 also has a decorative layer 30 between the base layer 40 and the transparent resin layer 20.

<Absorbance>
The decorative sheet of the present invention has an absorbance A1 of 0.6 or more and an absorbance A2 of 1.2 or more. A high absorbance A1 means that less light with wavelengths of 270 to 300 nm reaches the layer containing a polypropylene resin (transparent resin layer) located closer to the surface protective layer, and a high absorbance A2 means that less light with wavelengths of 270 to 300 nm reaches the layer containing a polypropylene resin (substrate layer) located farther from the surface protective layer.
Conventional decorative sheets are usually designed to add ultraviolet absorbents only to the surface protective layer (topcoat layer or primer layer). In other words, conventional decorative sheets are designed only for absorbance A1. However, there is a limit to improving the weather resistance of decorative sheets with a design based only on absorbance A1. That is, although the ultraviolet absorbents vary in their bleed-out tendency depending on the type, they are all lost over time by bleeding out from the inside of the layer to the outside of the layer, and their concentration decreases. Therefore, although the deterioration of the layer located inside the surface protective layer due to ultraviolet rays can be suppressed in the short term, it cannot be suppressed over the long term. Usually, weather resistance is evaluated as the time it takes for the deterioration of the entire decorative sheet due to ultraviolet rays to reach a predetermined level when exposed to sunlight including ultraviolet rays. Therefore, there is a limit to improving weather resistance with a design that increases only the absorbance A1 of the surface protective layer. Furthermore, in anticipation of the bleeding out of the ultraviolet absorber over time, a design that improves weather resistance by adding an excess amount of ultraviolet absorber to the surface protective layer may be considered. However, in this case, problems such as a decrease in the physical properties of the surface protective layer, such as scratch resistance and contamination resistance, due to the excessive addition of ultraviolet absorber, as well as deterioration in appearance, such as clouding of the surface, due to bleeding out of the excess ultraviolet absorber, may occur.
Therefore, in the present invention, an ultraviolet absorber is added not only to the surface protective layer but also to the transparent resin layer, and two types of absorbance (absorbance A1 and absorbance A2) are set to specific ranges, thereby solving the problem of long-term weather resistance while making bleed-out less likely to occur.

Polypropylene-based resins are significantly degraded by ultraviolet rays of 270 to 300 nm. Therefore, by blending an ultraviolet absorber that blocks ultraviolet rays in this specific wavelength range, it is possible to impart long-term durability to decorative sheets made of polypropylene-based resins.

The absorbance A1 must be 0.6 or more. If the absorbance A1 is less than 0.6, the transparent resin layer containing a polypropylene resin and the base layer containing a polypropylene resin will deteriorate over time due to ultraviolet rays, and the weather resistance of the decorative sheet will not be good.
The absorbance is preferably 0.7 or more, and more preferably 0.8 or more.

Moreover, from the viewpoint of suppressing bleed-out, the absorbance A1 is preferably 5.0 or less.
A large absorbance A1 means that the content of the ultraviolet absorber in the surface protective layer is large, or the thickness of the surface protective layer is large. When the content of the ultraviolet absorber in the surface protective layer is large, there is a tendency for bleeding out and the scratch resistance of the surface protective layer to decrease, and when the thickness of the surface protective layer is large, there is a tendency for the processing suitability of the decorative sheet to decrease. That is, when the absorbance A1 exceeds 5.0, any of the problems selected from the bleeding out of the ultraviolet absorber, the decrease in scratch resistance, and the decrease in processing suitability is likely to occur.
The absorbance A1 is more preferably 4.5 or less, more preferably 3.5 or less, and even more preferably 3.0 or less.

The absorbance A2 must be 1.2 or more. If the absorbance A2 is less than 1.2, the base layer containing a polypropylene resin will deteriorate over time due to ultraviolet rays, and the weather resistance of the decorative sheet will not be good.
The absorbance A2 is preferably 1.3 or more, and more preferably 1.4 or more.

Moreover, the absorbance A2 is preferably 5.0 or less from the viewpoint of suppressing bleed-out.
In the present invention, when the absorbance A2 exceeds 5.0, the ultraviolet absorbing agent is likely to bleed out from the decorative sheet.
The absorbance A2 is more preferably 4.5 or less, more preferably 4.0 or less, and even more preferably 3.5 or less.

The absorbance A1 and absorbance A2 can be adjusted, for example, by the content ratio of the ultraviolet absorber and the thickness of the layer containing the ultraviolet absorber.

The absorbance A2 is the average value of the absorbance measured at wavelengths of 270 to 300 nm of a laminate in which a surface protective layer is formed on a transparent resin layer in accordance with JIS K0115: 2004. In this specification, the average value of the absorbance at wavelengths of 270 to 300 nm is the average value of the absorbance measured at 1 nm intervals for wavelengths of 270 to 300 nm (a total of 31 absorbance values).
The absorbance A1 is obtained by measuring the absorbance A0 of the transparent resin layer at wavelengths of 270 to 300 nm in accordance with JIS K0115:2004 and subtracting the absorbance A0 from the absorbance A2 (absorbance A1=absorbance A2-absorbance A0). Note that the absorbance A0 is the average value of the absorbances measured at wavelengths of 270 to 300 nm of the transparent resin layer.

<Surface protective layer>
The surface protective layer is a layer located on the opposite side of the transparent resin layer from the substrate layer. The surface protective layer may be formed of a single layer, or may be formed of two or more layers as shown in FIG.
In this specification, the layer of the surface protective layer that is the furthest from the transparent resin layer is referred to as the "top coat layer". In other words, when the surface protective layer is formed of a single layer, the surface protective layer has a single-layer structure of the top coat layer. In addition, when the surface protective layer is formed of two or more layers, the layer located between the top coat layer and the transparent resin layer means a layer other than the top coat layer among the layers constituting the surface protective layer.
The topcoat layer preferably contains a cured product of a curable resin composition.
The surface protective layer preferably has a primer layer located closer to the transparent resin layer than the topcoat layer. By forming the surface protective layer from the topcoat layer and the primer layer and incorporating an ultraviolet absorber in both the topcoat layer and the primer layer, it is possible to easily suppress bleed-out of the ultraviolet absorber while suppressing deterioration over time due to ultraviolet rays.

The surface protective layer is mainly composed of a resin.
It is preferable that the resin constituting the surface protective layer does not substantially contain a polypropylene-based resin. In the present invention, the light having a wavelength of 270 to 300 nm that reaches the transparent resin layer is sufficiently restricted by specifying the absorbance A1, but a larger amount of light having a wavelength of 270 to 300 nm reaches the surface protective layer than the transparent resin layer. For this reason, it is preferable that the resin constituting the surface protective layer does not substantially contain a polypropylene-based resin, since it is easy to improve the weather resistance of the surface protective layer.
"Substantially free of polypropylene-based resin" means that the proportion of polypropylene-based resin is 1% by mass or less relative to the total resin components constituting the surface protective layer, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass.

<Ultraviolet absorbing agent>
At least one of the surface protective layer and the transparent resin layer preferably contains an ultraviolet absorbing agent, and it is more preferable that both the surface protective layer and the transparent resin layer contain an ultraviolet absorbing agent.
When the surface protective layer is formed of two or more layers, it is preferable that at least the top coat layer contains an ultraviolet absorber, and it is more preferable that all layers constituting the surface protective layer contain an ultraviolet absorber.
In addition, the following embodiments regarding the ultraviolet absorber are common to the ultraviolet absorber in the surface protective layer and the ultraviolet absorber in the transparent resin layer, unless otherwise specified.

Examples of the ultraviolet absorbent include benzotriazole-based ultraviolet absorbents, benzophenone-based ultraviolet absorbents, and triazine-based ultraviolet absorbents, among which triazine-based ultraviolet absorbents are preferred. Furthermore, among the triazine-based ultraviolet absorbents, hydroxyphenyltriazine-based ultraviolet absorbents are preferred from the viewpoint of weather resistance.
That is, the decorative sheet of the present invention preferably contains a triazine-based ultraviolet absorber in at least one of the surface protective layer and the transparent resin layer, and more preferably contains a hydroxyphenyltriazine-based ultraviolet absorber in at least one of the surface protective layer and the transparent resin layer.
Moreover, ultraviolet absorbents having a reactive functional group such as a (meth)acryloyl group, a vinyl group, or an allyl group are preferred because they are more likely to suppress bleed-out.

Hydroxyphenyltriazine-based UV absorbers include those represented by the following general formula (1):

In general formula (1), R ¹¹ is a divalent organic group, R ¹² is an acyloxy group represented by -O-C(=O)R ¹⁵ , R ¹³ , R ¹⁴ , and R ¹⁵ are each independently a hydrogen atom or a monovalent organic group, and n ₁₁ and n ₁₂ are each independently an integer of 0 to 5. In addition, when there are a plurality of R ¹³ and R ¹⁴ , they may be the same or different.
Examples of the divalent organic group for ^R11 include aliphatic hydrocarbon groups such as an alkylene group and an alkenylene group, and from the viewpoint of weather resistance, an alkylene group is preferred, and the number of carbon atoms therein is preferably 1 or more, more preferably 2 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, even more preferably 8 or less, and particularly preferably 4 or less. These aliphatic hydrocarbon groups may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred, and linear is more preferred.

From the viewpoint of weather resistance, R ¹³ and R ¹⁴ are preferably a hydrogen atom. When R ¹³ and R ¹⁴ are a monovalent organic group, preferred examples thereof include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. From the viewpoint of weather resistance, aromatic hydrocarbon groups such as an aryl group and an arylalkyl group are preferred, and an aryl group, particularly a phenyl group, is preferred.
R ¹⁵ is preferably a monovalent organic group from the viewpoint of weather resistance, and preferred examples thereof include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. From the viewpoint of weather resistance, an aliphatic hydrocarbon group such as an alkyl group or an alkenyl group is more preferred, and an alkyl group is even more preferred. When the monovalent organic group of R ¹⁵ is an aliphatic hydrocarbon group such as an alkyl group or an alkenyl group, it may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred, and the number of carbon atoms is preferably 2 or more, more preferably 4 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, and even more preferably 10 or less.

Specific examples of hydroxyphenyltriazine-based UV absorbers of general formula (1) include those of the following general formula (1-1). The hydroxyphenyltriazine-based UV absorber of the following general formula (1-1) is available from BASF under the trade name "Tinuvin 479".

Further, the hydroxyphenyltriazine-based ultraviolet absorber also includes those represented by the following general formula (2).
The hydroxyphenyltriazine compound represented by the general formula (2) does not contain an ester bond in the molecule, and therefore the molecular structure is not easily displaced. Therefore, the hydroxyphenyltriazine compound represented by the general formula (2) is preferable in terms of being superior in suppressing bleed-out and maintaining long-term weather resistance to the hydroxyphenyltriazine compound represented by the general formula (1).
The change in molecular structure starting from the ester bond is believed to be caused by acidic conditions, and therefore the hydroxyphenyltriazine compound represented by the general formula (2) can exhibit excellent effects when used outdoors where it is exposed to acid rain.

In general formula (2), R ²¹ is a monovalent organic group, R ²¹ is a hydrogen atom or a monovalent organic group, R ²² and R ²³ are each independently a hydroxyl group or a monovalent organic group, and n ₂₁ , n ₂₂ and n ₂₃ are each independently an integer of 1 to 5. In addition, when there are a plurality of R ²¹ , R ²² and R ²³ , they may be the same or different.

As the monovalent organic group of R ²¹ , R ²² and R ²³ , those exemplified as the monovalent organic group of R ¹³ and R ¹⁴ in the above general formula (1) are preferably mentioned, and from the viewpoint of weather resistance, aliphatic hydrocarbon groups such as alkyl groups and alkenyl groups are more preferable, and alkyl groups are even more preferable. In this case, the monovalent organic group of R ²¹ , R ²² and R ²³ may be linear, branched or cyclic, and from the viewpoint of weather resistance, linear or branched is preferable, and linear is more preferable. In addition, from the viewpoint of weather resistance, the carbon number is preferably 2 or more, more preferably 3 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, and even more preferably 8 or less.
In addition, _n21 , _n22 and _n23 are preferably 2 or more, and a plurality of ^R21 , ^R22 and ^R23 may be the same or different, and from the viewpoint of weather resistance, a plurality of ^R21 are preferably the same, and ^R22 and ^R23 are preferably different. It is preferable that one of the different ^R22 and ^R23 is a hydrogen atom. In addition, when ^R21 , ^R22 and ^R23 are monovalent organic groups, they are preferably the same organic group.

Specific examples of hydroxyphenyltriazine-based UV absorbers of general formula (2) include those of the following general formula (2-1). The hydroxyphenyltriazine-based UV absorber of general formula (2-1) is available from BASF under the trade name "Tinuvin 1600".

The content of the ultraviolet absorber in the surface protective layer is not particularly limited as long as the absorbance A1 is 0.6 or more. By making the content of the ultraviolet absorber in the surface protective layer a predetermined amount or more, the absorbance A1 can be easily made 0.6 or more. In addition, by making the content of the ultraviolet absorber in the surface protective layer a predetermined amount or less, bleeding out can be easily suppressed.
The content of the ultraviolet absorber in the top coat layer constituting the surface protection layer is preferably 0.5 parts by mass or more and 10.0 parts by mass or less, more preferably 1.0 parts by mass or more and 8.0 parts by mass or less, even more preferably 2.0 parts by mass or more and 7.0 parts by mass or less, and even more preferably 3.0 parts by mass or more and 5.0 parts by mass or less, relative to 100 parts by mass of the resin constituting the top coat layer.
In addition, when the other layer constituting the surface protective layer contains an ultraviolet absorbing agent, the content of the ultraviolet absorbing agent in the other layer is preferably 1 part by mass or more and 40 parts by mass or less, more preferably 5 parts by mass or more and 30 parts by mass or less, and even more preferably 7 parts by mass or more and 25 parts by mass or less, relative to 100 parts by mass of the resin constituting the other layer. An example of the other layer is a primer layer.

Radical Scavenger
At least one of the surface protective layer and the transparent resin layer preferably contains a radical scavenger. The surface protective layer is the layer that UV rays first enter among the layers constituting the decorative sheet, so it is preferable that the surface protective layer contains a radical scavenger. When the surface protective layer has a multi-layer structure, it is preferable that the top coat layer contains a radical scavenger.
In addition, the following embodiment regarding the radical scavenger is an embodiment common to the radical scavenger in the surface protective layer and the radical scavenger in the transparent resin layer, unless otherwise specified.

Radical scavengers include aromatic radical scavengers, amine radical scavengers, organic acid radical scavengers, catechin radical scavengers, and hindered amine radical scavengers, and among these, hindered amine radical scavengers are preferred. Hindered amine radical scavengers have a structure that includes a 2,2,6,6-tetramethylpiperidine skeleton in the molecule.

When the surface protective layer contains a radical scavenger, it is preferable that the radical scavenger contains a radical scavenger i having an ethylenic double bond polymerizable with the resin constituting the surface protective layer, and a radical scavenger ii not having an ethylenic double bond polymerizable with the resin constituting the surface protective layer.
The ethylenic double bond is contained in functional groups such as a (meth)acryloyl group, a vinyl group, and an allyl group.

When only the radical scavenger i is used, the radical scavenger in the surface protective layer is almost entirely immobilized, and there is almost no radical scavenger that can move freely within the surface protective layer, making it difficult to exhibit the radical scavenging performance. On the other hand, since the radical scavenger i polymerizes with the resin that constitutes the surface protective layer, when the resin that constitutes the surface protective layer contains a cured product (particularly a cured product of an ionizing radiation curable resin composition), the crosslink density of the cured product (particularly a cured product of an ionizing radiation curable resin composition) is reduced by the radical scavenger i, and the scratch resistance is likely to decrease.
On the other hand, when only radical scavenger II is used, radical scavenger II is likely to bleed out from the surface protective layer over time, which may result in a loss of aesthetic appeal of the decorative sheet surface and make it difficult to maintain radical scavenging performance over the long term.
Therefore, it is preferable that the surface protective layer contains the radical scavengers i and ii from the viewpoints of radical scavenging properties, scratch resistance, and suppression of bleed-out. When the surface protective layer has a multi-layer structure, it is preferable that the top coat layer contains the radical scavengers i and ii.

The blending ratio of the radical scavenger i to the radical scavenger ii on a mass basis is preferably 8:2 to 2:8.
By making the radical scavenger i 8 and the radical scavenger ii 2 or more, it is possible to improve weather resistance and to easily suppress a decrease in the crosslink density of the cured product of the surface protective layer. In addition, by making the radical scavenger i 2 and the radical scavenger ii 8 or less, it is possible to easily suppress bleeding out of the radical scavenger ii.

The content of the radical scavenger in the top coat layer constituting the surface protection layer is preferably 0.5 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 8 parts by mass or less, and even more preferably 1.5 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the resin constituting the top coat layer.
Furthermore, when the other layer constituting the surface protective layer contains a radical scavenger, the content of the radical scavenger in the other layer is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 8 parts by mass or less, and even more preferably 1 part by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the resin constituting the other layer.

The radical scavenger i has an ethylenic double bond that can be polymerized with the resin that constitutes the surface protective layer. Examples of the group having an ethylenic double bond include a (meth)acryloyl group, a crotonoyl group, a vinyl group, and an allyl group, and among these, a (meth)acryloyl group is preferred. That is, the radical scavenger i is preferably one having a (meth)acryloyl group.
The number of ethylenic double bonds in the radical scavenger i is not particularly limited, and may be 1 or may be 2 or more. In addition, only one type of radical scavenger i may be used, or two or more types of radical scavenger i may be used.

Examples of the radical scavenger i having one ethylenic double bond include 4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 4-(meth)acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4-(meth)acryloylamino-1,2,2,6,6-pentamethylpiperidine, 4- Examples thereof include cyano-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine and 4-crotonoylamino-2,2,6,6-tetramethylpiperidine, pentamethylpiperidinyl (meth)acrylate, the compound having CAS No. 1010692-24-6, and the compound having CAS No. 1010692-21-3.
Examples of the radical scavenger i having two or more ethylenic double bonds include 1-(meth)acryloyl-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 1-(meth)acryloyl-4-cyano-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 1-crotonoyl-4-crotoyloxy-2,2,6,6-tetramethylpiperidine, the compound having CAS No. 1954659-42-7, and the compound having CAS No. 1010692-23-5.

The radical scavenger II does not have an ethylenic double bond that can be polymerized with the resin that constitutes the surface protective layer. Only one type of radical scavenger II may be used, or two or more types may be used.

Radical scavengers II include 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, and methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate. , 2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethyl-4-piperidinyl)amino]-6-(2-hydroxyethylamine)-1,3,5-triazine), tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(3,5-di-t-butyl-4-hydroxy-benzyl)-2-n-butylmalonate, etc.

Topcoat layer
The top coat layer preferably contains a cured product of a curable resin composition in order to enhance the scratch resistance of the decorative sheet.
Furthermore, the proportion of the cured product of the curable resin composition relative to all resin components constituting the top coat layer is preferably 50 mass % or more, more preferably 70 mass % or more, and even more preferably 80 mass % or more.

The cured product of the curable resin may be a cured product of a thermosetting resin, a cured product of an ionizing radiation curable resin, or a mixture of these. Among these, a cured product of an ionizing radiation curable resin composition is preferred from the viewpoint of increasing the crosslink density of the topcoat layer and improving scratch resistance and weather resistance. Furthermore, among ionizing radiation curable resin compositions, a cured product of an electron beam curable resin composition is more preferred from the viewpoint of being able to be applied without a solvent and being easy to handle.

A thermosetting resin composition is a composition that contains at least a thermosetting resin, and is a resin composition that hardens when heated. Examples of thermosetting resins include acrylic resins, urethane resins, phenolic resins, urea melamine resins, epoxy resins, unsaturated polyester resins, and silicone resins. In a thermosetting resin composition, a curing agent is added to these hardenable resins as necessary.

-Ionizing radiation curable resin-
The ionizing radiation curable resin composition is a composition containing a compound having an ionizing radiation curable functional group (hereinafter, also referred to as an "ionizing radiation curable compound"). It is a group that crosslinks and hardens upon irradiation, and preferred examples thereof include functional groups having an ethylenic double bond, such as a (meth)acryloyl group, a vinyl group, and an allyl group.
In addition, ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Usually, ultraviolet rays (UV) or electron beams (EB) are used, but other types include: It also includes electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as alpha rays and ion beams.
Specifically, the ionizing radiation curable compound can be appropriately selected from polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation curable resins.

As the polymerizable monomer, a (meth)acrylate monomer having a radically polymerizable unsaturated group in the molecule is preferable, and among them, a polyfunctional (meth)acrylate monomer is preferable. Here, "(meth)acrylate" means "acrylate or methacrylate".
The polyfunctional (meth)acrylate monomer includes a (meth)acrylate monomer having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group.
From the viewpoint of improving processing characteristics, scratch resistance, and weather resistance, the number of functional groups of the polyfunctional (meth)acrylate monomer is preferably from 2 to 8, more preferably from 2 to 6, even more preferably from 2 to 4, and even more preferably from 2 to 3. These polyfunctional (meth)acrylates may be used alone or in combination of two or more kinds.

Examples of the polymerizable oligomer include (meth)acrylate oligomers having two or more ionizing radiation-curable functional groups in the molecule and having at least a (meth)acryloyl group as the functional group, such as urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers.
Further examples of the polymerizable oligomer include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acrylate groups in the side chains of polybutadiene oligomers, silicone (meth)acrylate oligomers having polysiloxane bonds in the main chains, aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in a small molecule, and oligomers having cationically polymerizable functional groups in the molecule, such as novolac type epoxy resins, bisphenol type epoxy resins, aliphatic vinyl ethers, and aromatic vinyl ethers.

These polymerizable oligomers may be used alone or in combination. From the viewpoint of improving processing characteristics, scratch resistance, and weather resistance, urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers are preferred, urethane (meth)acrylate oligomers and polycarbonate (meth)acrylate oligomers are more preferred, and urethane (meth)acrylate oligomers are even more preferred.

From the viewpoint of improving processing characteristics, scratch resistance, and weather resistance, the number of functional groups of these polymerizable oligomers is preferably 2 or more and 8 or less, and the upper limit is more preferably 6 or less, even more preferably 4 or less, and even more preferably 3 or less.
From the viewpoint of improving processing characteristics, scratch resistance and weather resistance, the weight average molecular weight of these polymerizable oligomers is preferably from 2,500 to 7,500, more preferably from 3,000 to 7,000, and even more preferably from 3,500 to 6,000. Here, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

In the ionizing radiation curable resin composition, monofunctional (meth)acrylates can be used in combination for the purpose of reducing the viscosity of the ionizing radiation curable resin composition. These monofunctional (meth)acrylates may be used alone or in combination of two or more types.

From the viewpoint of balancing processing characteristics, scratch resistance, and weather resistance, the thickness of the topcoat layer is preferably 1.5 μm or more and 20 μm or less, more preferably 2 μm or more and 15 μm or less, and even more preferably 3 μm or more and 10 μm or less.

<Primer layer>
The decorative sheet of the present embodiment preferably has, as a surface protective layer, a primer layer formed on the transparent resin layer side of the topcoat layer in addition to the topcoat layer. The primer layer can improve the adhesion between the topcoat layer and the transparent resin layer.

The primer layer is mainly composed of a binder resin, and may contain additives such as an ultraviolet absorber and a radical scavenger, if necessary.
Preferred examples of the binder resin include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, polycarbonate-based urethane-acrylic copolymer (urethane-acrylic copolymer derived from a polymer (polycarbonate polyol) having a carbonate bond in the polymer main chain and having two or more hydroxyl groups at the end and side chain), vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin (nitrocellulose), and cellulose acetate resin. These can be used alone or in combination. For example, a mixture of a polycarbonate-based urethane-acrylic copolymer and an acrylic polyol resin can be used as the binder resin.

The thickness of the primer layer is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 6 μm or less.

<Transparent resin layer>
The transparent resin layer is a layer containing a polypropylene-based resin, and is located between the surface protective layer and the substrate layer.
From the viewpoint of processability, the content of the polypropylene-based resin in the transparent resin layer is preferably 50 mass% or more, more preferably 60 mass% or more, and even more preferably 70 mass% or more, based on the total resin components of the transparent resin layer.

Examples of polypropylene-based resins for the transparent resin layer include polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, and ethylene-propylene-butene copolymer. Among these, polypropylene, ethylene-propylene copolymer, and propylene-butene copolymer are preferred, and polypropylene is more preferred.

When the transparent resin layer contains a resin other than a polypropylene-based resin, for example, a thermoplastic resin such as a polyolefin-based resin other than a polypropylene-based resin (polyethylene, polymethylpentene, polybutene, etc.), a polyester resin, a polycarbonate resin, an acrylonitrile-butadiene-styrene resin (hereinafter also referred to as "ABS resin"), an acrylic resin, or a polyvinyl chloride resin can be used.

As described above, the transparent resin layer preferably contains an ultraviolet absorbing agent and a radical scavenger.
The content of the ultraviolet absorbing agent in the transparent resin layer is not particularly limited as long as the absorbance A2 is 1.2 or more.
In addition, when the thickness of the transparent resin layer is within the range described below, the content of the ultraviolet absorber in the transparent resin layer is preferably 0.05 parts by mass or more and 10 parts by mass or less, more preferably 0.07 parts by mass or more and 5 parts by mass or less, even more preferably 0.09 parts by mass or more and 3 parts by mass or less, and even more preferably 0.10 parts by mass or more and 1 part by mass or less, relative to 100 parts by mass of the resin constituting the transparent resin layer.
Furthermore, when the thickness of the transparent resin layer is within the range described below, the content of the radical scavenger in the transparent resin layer is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 8 parts by mass or less, even more preferably 1 part by mass or more and 5 parts by mass or less, and even more preferably 1.5 parts by mass or more and 3 parts by mass or less, relative to 100 parts by mass of the resin constituting the transparent resin layer.

The transparent resin layer may be transparent enough to allow the substrate layer side to be seen through the transparent resin layer, and may be colorless and transparent, colored, transparent, or translucent.

The thickness of the transparent resin layer is preferably from 20 μm to 150 μm, more preferably from 40 μm to 120 μm, and even more preferably from 60 μm to 100 μm, from the viewpoint of a balance between scratch resistance, processability, and weather resistance.
In addition, the thickness of the transparent resin layer is preferably thicker than that of the base layer, from the viewpoints of protecting the decorative layer and obtaining excellent scratch resistance.

<Base layer>
The base layer is a layer containing a polypropylene-based resin, and is located on the opposite side of the transparent resin layer to the surface protective layer.
From the viewpoint of processability, the content of the polypropylene-based resin in the base layer is preferably 50 mass% or more, more preferably 60 mass% or more, even more preferably 70 mass% or more, and even more preferably 80 mass% or more, based on the total resin components of the base layer.

Examples of polypropylene resins for the base layer include polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, and ethylene-propylene-butene copolymer. Among these, polypropylene, ethylene-propylene copolymer, and propylene-butene copolymer are preferred, and polypropylene is more preferred.

When the base layer contains a resin other than polypropylene-based resin, for example, thermoplastic resins such as polyolefin-based resins other than polypropylene-based resins (polyethylene, polymethylpentene, polybutene, etc.), polyester resins, polycarbonate resins, acrylonitrile-butadiene-styrene resins (hereinafter also referred to as "ABS resins"), acrylic resins, and polyvinyl chloride resins can be used.

The substrate layer may be colorless and transparent, but is preferably colored from the viewpoint of design.
When the base layer is colored, a coloring agent such as a dye or a pigment can be added to the base layer. Among these coloring agents, a pigment is preferred because it is easy to suppress fading.
Examples of pigments include white pigments such as zinc oxide, white lead, lithopone, titanium dioxide, precipitated barium sulfate, and baryte; black pigments such as carbon black; red pigments such as red lead and red iron oxide;
Examples of the pigment include yellow pigments such as yellow lead and zinc yellow (zinc yellow type 1, zinc yellow type 2), and blue pigments such as ultramarine blue and Prussian blue (potassium ferrocyanide).

The content of the colorant is, for example, preferably 1 part by mass or more and 50 parts by mass or less, more preferably 3 parts by mass or more and 40 parts by mass or less, even more preferably 5 parts by mass or more and 30 parts by mass or less, and even more preferably 5 parts by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the resin constituting the base layer.

The base layer may contain additives as necessary. Examples of additives include inorganic fillers such as calcium carbonate and clay, flame retardants such as magnesium hydroxide, antioxidants, lubricants, foaming agents, ultraviolet absorbers, and radical scavengers. The amount of additives may be appropriately adjusted within a range that does not impair the effects of the present invention.
In the present invention, since the absorbances A1 and A2 are set within predetermined ranges, it is preferable that the weather resistance of the base layer can be improved without containing an ultraviolet absorber and a radical scavenger in the base layer.

From the viewpoint of a balance between design and processability, the thickness of the base layer is preferably 20 μm or more and 150 μm or less, more preferably 25 μm or more and 120 μm or less, even more preferably 30 μm or more and 100 μm or less, and even more preferably 40 μm or more and 80 μm or less.

In order to increase adhesion to other layers of the decorative sheet or to the adherend, one or both sides of the base layer may be subjected to a physical surface treatment such as an oxidation method or a roughening method, or a chemical surface treatment, or a primer layer may be formed.

<Decorative layer>
From the viewpoint of improving the design, the decorative sheet of the present invention preferably has a decorative layer at any position of the decorative sheet. From the viewpoint of improving the weather resistance of the decorative layer, the position where the decorative layer is formed is preferably between the substrate layer and the transparent resin layer.

The decorative layer may be, for example, a colored layer that covers the entire surface (a so-called solid colored layer), or a patterned layer formed by printing various patterns using ink and a printing machine, or a combination of these.

The ink used for the decorative layer is a suitable mixture of a binder resin, a pigment, a colorant such as a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a hardener, an ultraviolet absorber, a radical scavenger, etc.
The binder resin of the decorative layer is not particularly limited, and examples thereof include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin, cellulose acetate resin, etc. In addition, various types of resins can be used, such as one-component curing resins and two-component curing resins accompanied by a curing agent such as an isocyanate compound.

As the colorant, a pigment having excellent hiding power and weather resistance is preferable. The same pigments as those exemplified for the base layer can be used.
The content of the colorant in the base layer is preferably 5 parts by mass or more and 90 parts by mass or less, more preferably 15 parts by mass or more and 80 parts by mass or less, and even more preferably 30 parts by mass or more and 70 parts by mass or less, relative to 100 parts by mass of the resin constituting the decorative layer.

From the viewpoint of improving weather resistance, it is preferable that the decorative layer contains a weather resistance agent such as an ultraviolet absorber or a radical scavenger.

The thickness of the decorative layer may be appropriately selected according to the desired pattern, but from the viewpoint of concealing the base color of the adherend and improving the design, it is preferably 0.5 μm to 20 μm, more preferably 1 μm to 10 μm, and even more preferably 2 μm to 5 μm.

<Adhesive Layer A>
It is preferable to form an adhesive layer A between the substrate layer and the transparent resin layer in order to improve the adhesion between the two layers.
In addition, when the above-mentioned decorative layer is further provided between the base layer and the transparent resin layer, the positional relationship between the adhesive layer A and the decorative layer is not particularly limited. Specifically, the decorative layer and the adhesive layer A may be provided in this order from the side closer to the base layer, or the adhesive layer A and the decorative layer may be provided in this order from the side closer to the base layer.

The adhesive layer A can be made of, for example, an adhesive such as a urethane adhesive, an acrylic adhesive, an epoxy adhesive, a rubber adhesive, etc. Among these adhesives, a urethane adhesive is preferred in terms of adhesive strength.
Examples of urethane-based adhesives include adhesives that utilize two-component curing urethane resins that contain various polyol compounds such as polyether polyols, polyester polyols, and acrylic polyols, and curing agents such as the various isocyanate compounds described above.

The thickness of adhesive layer A is preferably 0.1 μm or more and 30 μm or less, more preferably 1 μm or more and 15 μm or less, and even more preferably 2 μm or more and 10 μm or less.

The decorative layer, adhesive layer A, primer layer and topcoat layer described above can be formed by applying a coating liquid containing the composition that forms each layer using a known method such as gravure printing, bar coating, roll coating, reverse roll coating or comma coating, and then drying and curing as necessary.

The decorative sheet of the present invention may be provided with unevenness by embossing or the like.
When embossing is performed, for example, the decorative sheet is heated to preferably from 80° C. to 260° C., more preferably from 100° C. to 220° C., and even more preferably from 120° C. to 200° C., and an embossing plate is pressed against the decorative sheet to perform the embossing. The area to be pressed with the embossing plate is preferably the surface protective layer side of the decorative sheet.

[Cosmetic materials]
The decorative material of the present invention comprises an adherend and the decorative sheet of the present invention described above, and specifically, is laminated so that the surface of the adherend that requires decoration faces the substrate layer side of the decorative sheet.

<Adherend>
Examples of the adherend include various materials such as flat plates, curved plates, three-dimensional articles, and sheets (or films). For example, wood members used as boards and three-dimensional articles such as wood veneers, wood plywood, particle boards, and wood fiberboards such as MDF (medium density fiberboard) made of various wood materials such as cedar, cypress, pine, and lauan; metal members used as steel plates, three-dimensional articles, and sheets of iron and aluminum; ceramic members used as boards and three-dimensional articles such as glass, ceramics such as porcelain, non-cement ceramic materials such as gypsum, and non-ceramic ceramic materials such as ALC (lightweight aerated concrete) boards; resin members used as boards, three-dimensional articles, and sheets of acrylic resins, polyester resins, polystyrene resins, polypropylene resins, and other polyolefin resins, ABS (acrylonitrile-butadiene-styrene copolymer) resins, phenolic resins, vinyl chloride resins, cellulose resins, and rubber. These members can be used alone or in combination of two or more. The decorative material of the present invention is preferable in that, when the adherend contains a polypropylene-based resin, the weather resistance of the adherend can be improved.

The adherend may be appropriately selected from the above depending on the application.
When the adherend is used as an interior or exterior member of a building such as a wall, ceiling, or floor, or as a fitting or fixture member such as a window frame, door, handrail, baseboard, molding, or the like, the material of the adherend is preferably at least one member selected from wood members, metal members, and resin members. When the adherend is used as an exterior member such as an entrance door, or as fittings such as a window frame or door, the material of the adherend is preferably at least one member selected from metal members and resin members.

The thickness of the adherend may be selected appropriately depending on the application and material, and is preferably 0.1 mm to 10 mm, more preferably 0.3 mm to 5 mm, and even more preferably 0.5 mm to 3 mm.

<Adhesive Layer B>
In order to obtain excellent adhesion, the adherend and the decorative sheet are preferably attached to each other via the adhesive layer B.

The adhesive used in the adhesive layer B is not particularly limited, and a known adhesive can be used, and preferable examples include adhesives such as heat-sensitive adhesives and pressure-sensitive adhesives. Examples of the resin used in the adhesive constituting this adhesive layer include acrylic resins, polyurethane resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, styrene-acrylic copolymer resins, polyester resins, polyamide resins, and the like, and these can be used alone or in combination of two or more kinds. In addition, two-liquid curing type polyurethane adhesives and polyester adhesives using an isocyanate compound or the like as a curing agent can also be applied.
A pressure-sensitive adhesive may also be used for the adhesive layer B. The pressure-sensitive adhesive may be appropriately selected from acrylic, urethane, silicone, rubber, and other pressure-sensitive adhesives.

There are no particular limitations on the thickness of adhesive layer B, but from the viewpoint of obtaining excellent adhesion, it is preferably 1 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less, and even more preferably 10 μm or more and 30 μm or less.

Next, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.

1. Evaluation and Measurement 1-1. Absorbance Using an ultraviolet-visible near-infrared spectrophotometer (manufactured by Hitachi, Ltd., product name: U-4000), the absorbance A2 of a laminate having a surface protective layer formed on a transparent resin layer at a wavelength of 270 to 300 nm was measured in accordance with JIS K0115:2004, and the average value was calculated. In addition, the absorbance A0 of the transparent resin layer at a wavelength of 270 to 300 nm was measured by the same means, and the absorbance A0 was subtracted from the absorbance A2 to calculate the absorbance A1 of the surface protective layer at a wavelength of 270 to 300 nm.

1-2. Weather resistance Using the following accelerated weather resistance tester, the decorative sheets obtained in the Examples and Comparative Examples were irradiated with ultraviolet light for 20 hours under conditions of a black panel temperature of 63°C and an illuminance of 100 mW/ ^cm2 , followed by condensation for 4 hours, and the cycle was repeated. After 1000 hours and 1400 hours, the appearance of the decorative sheets was visually evaluated according to the following criteria.
<Ultra-accelerated weather resistance test equipment>
Ultra-accelerated weather resistance test equipment (product name: "Eye Super UV Tester SUV-W161", manufactured by Iwasaki Electric Co., Ltd.) including a UV lamp (product name: M04-L21WB/SUV, manufactured by Iwasaki Electric Co., Ltd.), a lamp jacket (product name: WJ50-SUV, manufactured by Iwasaki Electric Co., Ltd.), and an illuminometer (product name: UVD-365PD, manufactured by Iwasaki Electric Co., Ltd.)
<Evaluation criteria>
A: No change in appearance was observed over the entire decorative sheet.
B: Slight whitening was observed in the appearance of the decorative sheet, but no change in color tone was observed in the transparent resin layer and/or the base layer.
C: Slight whitening was observed on the appearance of the decorative sheet, and slight color change was observed in the transparent resin layer and/or the base layer.
D: Significant whitening of the appearance of the decorative sheet and significant change in color tone of the transparent resin layer and/or the substrate layer were observed.

The decorative sheets obtained in the Examples and Comparative Examples were immersed in a constant temperature bath of 60°C hot water for one week, then removed and thoroughly dried, and the appearance was observed visually and using a non-contact shape analysis laser microscope (Keyence: VK-X1000), and evaluated according to the following criteria.
A: No change in appearance was observed.
B: Slight changes in appearance such as swelling, bubbles, gloss change, and precipitation of sheet components were observed.
C: Significant changes in appearance such as swelling, bubbles, gloss change, and precipitation of sheet components were observed.

2. Preparation of decorative sheet [Example 1]
A decorative layer was formed on one side of a substrate layer (a 60 μm-thick colored polypropylene resin sheet) that had been subjected to a corona discharge treatment on both sides, using a printing ink made of a two-component curing acrylic-urethane resin. Next, an adhesive layer made of a urethane resin adhesive and having a thickness of 3 μm was formed on the decorative layer.
Next, on the adhesive layer, a composition A containing 0.12 parts by mass of a hydroxyphenyltriazine-based ultraviolet absorber (product name: TINUVIN 479, manufactured by BASF) and 0.12 parts by mass of a hydroxyphenyltriazine-based ultraviolet absorber (product name: Adeka STAB LA-46, manufactured by ADEKA Corporation) per 100 parts by mass of polypropylene-based resin was hot-melt extruded by a T-die extruder to form a transparent resin layer having a thickness of 80 μm.
The surface of the transparent resin layer was subjected to a corona discharge treatment, and then the following composition B was applied onto the transparent resin layer and dried to form a primer layer having a thickness of 4 μm.
<Composition B>
A composition obtained by mixing 100 parts by mass of composition X (a composition comprising a polycarbonate-based urethane-acrylic copolymer and an acrylic polyol, and hexamethylene diisocyanate in a mass ratio of 100:5) with 10 parts by mass of a hydroxyphenyltriazine-based ultraviolet absorber (product name: TINUVIN 400, manufactured by BASF Corporation).

Next, the following composition C was applied onto the primer layer, and the ionizing radiation curable resin composition was cured by irradiating with an electron beam, thereby forming a top coat layer having a thickness of 5 μm.
Next, a 50 μm deep wood grain vessel-like uneven pattern was formed on the top coat layer by embossing, and the decorative sheet of Example 1 was obtained.

<Composition C>
Ionizing radiation curable resin composition 100 parts by mass (trifunctional urethane acrylate oligomer having a weight average molecular weight of 4000)
Hydroxyphenyltriazine-based ultraviolet absorber: 1 part by mass (product name: TINUVIN 1600, manufactured by BASF)
Hydroxyphenyltriazine-based ultraviolet absorber: 2 parts by mass (product name: TINUVIN 479, manufactured by BASF)
Hindered amine radical scavenger i having an ethylenic double bond capable of reacting with an ionizing radiation curable resin: 1.5 parts by mass (pentamethylpiperidinyl methacrylate)
Hindered amine radical scavenger II having no ethylenic double bond capable of reacting with ionizing radiation curable resins: 3.0 parts by mass (bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl)sebacate)

[Examples 2 to 5], [Comparative Examples 1 to 4], [Reference Example 1]
Except for changing the ultraviolet absorber in the transparent resin layer and the ultraviolet absorber in the topcoat layer to those in Table 1, the decorative sheets of Examples 2 to 5, Comparative Examples 1 to 4, and Reference Example 1 were obtained in the same manner as in Example 1.

From the results in Table 1, it can be confirmed that the decorative sheets of the examples, which have an absorbance A1 of 0.6 or more and an absorbance A2 of 1.2 or more, can suppress deterioration over time due to ultraviolet rays.

The decorative sheet of the present invention has excellent weather resistance and is therefore suitable for use as a decorative sheet for components that are used in environments exposed to direct sunlight, such as exterior components such as entrance doors, window frames, doors, and other fixtures.

100: Decorative sheet 11: Topcoat layer 12: Primer layer 10: Surface protective layer 20: Transparent resin layer 30: Decorative layer 40: Base material layer

Claims (8)

a surface protective layer, a transparent resin layer containing a polypropylene-based resin, and a base layer containing a polypropylene-based resin in this order, the surface protective layer having a top coat layer and a primer layer located on the transparent resin layer side of the top coat layer, the top coat layer, the primer layer and the transparent resin layer each containing an ultraviolet absorber;
The decorative sheet has an absorbance A1, which is an average value of the absorbance per nm at wavelengths of 270 to 300 nm of the surface protective layer, measured in accordance with JIS K0115:2004, of 0.6 to 3.0 , and an absorbance A2, which is an average value of the absorbance per nm at wavelengths of 270 to 300 nm of the surface protective layer and the transparent resin layer, measured in accordance with JIS K0115:2004, of 1.2 to 4.0 . 2. The decorative sheet according to claim 1, wherein the ultraviolet absorbing agent is a triazine-based ultraviolet absorbing agent. 3. The decorative sheet according to claim 2, wherein the triazine-based ultraviolet absorber comprises a hydroxyphenyltriazine compound represented by the following general formula (I):
The decorative sheet according to any one of claims 1 to 3, wherein the top coat layer comprises a radical scavenger i having an ethylenic double bond polymerizable with a resin constituting the top coat layer , and a radical scavenger ii having no ethylenic double bond polymerizable with a resin constituting the surface protective layer. The decorative sheet according to any one of claims 1 to 4, wherein the resin constituting the surface protective layer is substantially free of polypropylene-based resin. The decorative sheet according to any one of claims 1 to 5 , wherein the top coat layer comprises a cured product of a curable resin composition. The decorative sheet according to any one of claims 1 to 6 , further comprising a decorative layer between said base layer and said transparent resin layer. A decorative material comprising an adherend and the decorative sheet according to any one of claims 1 to 7 .