WO2021199671A1

WO2021199671A1 - Decorative sheet and decorative material using same

Info

Publication number: WO2021199671A1
Application number: PCT/JP2021/004136
Authority: WO
Inventors: 真友子小紫; 古田　哲
Original assignee: 大日本印刷株式会社
Priority date: 2020-03-31
Filing date: 2021-02-04
Publication date: 2021-10-07
Also published as: JP2021160290A

Abstract

The present invention suppresses deterioration over time of a decorative sheet due to ultraviolet light, said decorative sheet being obtained by stacking layers each containing a polypropylene resin.　A decorative sheet which sequentially comprises a surface protection layer, a transparent resin layer that contains a polypropylene resin, and a base material layer that contains a polypropylene resin in this order, wherein: the absorbance A1 of the surface protection layer at a wavelength from 270 nm to 300 nm as determined in accordance with JIS K0115 (2004) is 0.6 or more; and the absorbance A2 of the surface protection layer and the transparent resin layer that contains a polypropylene resin at a wavelength from 270 nm to 300 nm as determined in accordance with JIS K0115 (2004) is 1.2 or more.

Description

Decorative sheet and decorative material using it

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

Conventionally, decorative sheets have been used to decorate and protect the surfaces of building interior members, building exterior members, furniture, building members, home appliances, and the like. The decorative sheet has, for example, a configuration having a surface protective layer on a base material.

These decorative sheets cause color change and resin deterioration due to the influence of ultraviolet rays in outdoor use and indoor use where they are exposed to sunlight near windows. Therefore, for the purpose of improving the weather resistance, an ultraviolet absorber is added to the surface protective layer of the decorative sheet.

However, there is a problem that the UV absorber tends to bleed out from the surface protective layer over time. When the ultraviolet absorber bleeds out, there is a problem that the appearance of the surface of the decorative sheet is spoiled and the concentration of the ultraviolet absorber in the surface protective layer decreases with time, resulting in insufficient weather resistance of the decorative sheet. For example, Patent Document 1 has been proposed in order to eliminate the bleeding of the ultraviolet absorber.

Japanese Unexamined Patent Publication No. 2000-117905

The decorative sheet of Patent Document 1 contains an electron beam-reactive ultraviolet absorber selected from a specific benzotriazole-based compound or the like in a cured layer of a resin containing an electron beam-curable resin as a main component. The decorative sheet of Patent Document 1 can solve the problem of bleed-out of the ultraviolet absorber.

On the other hand, decorative sheets are often required to have processing suitability such as embossing, bending, and molding. For this reason, in recent years, a decorative sheet has been proposed in which a base material layer containing a polypropylene-based resin having excellent processability is used as the base material layer, and a surface protective layer is laminated on the base material layer. When the surface protective layer of Patent Document 1 is applied as the surface protective layer of the decorative sheet having the surface protective layer on the base material layer containing such a polypropylene resin, the bleed-out of the ultraviolet absorber in the surface protective layer occurs. Even if it was suppressed, there were many cases where it was not possible to suppress the deterioration of the decorative sheet over time due to ultraviolet rays.

The present invention has been made under such circumstances, and an object of the present invention is to suppress deterioration over time due to ultraviolet rays in a decorative sheet formed by laminating layers containing a polypropylene resin and a decorative material using the same. Is.

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

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

It is sectional drawing which shows one Embodiment of the decorative sheet of this invention.

[Cosmetic 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 material layer containing a polypropylene-based resin in this order, and the surface protection measured in accordance with JIS K0115: 2004. The absorbance A1 of the layer at a wavelength of 270 nm to 300 nm is 0.6 or more, and the absorbance A2 of the surface protective layer and the transparent resin layer measured according to JIS K0115: 2004 is 1.2 at a wavelength of 270 nm to 300 nm. That is all.

In the present specification, "absorbance A1 of the surface protective layer measured in accordance with JIS K0115: 2004 at a wavelength of 270 nm to 300 nm" is referred to as "absorbance A1" and "absorbance A1 measured in accordance with JIS K0115: 2004". The "absorbance A2" of the protective layer and the transparent resin layer at a wavelength of 270 nm to 300 nm may be referred to as "absorbance A2". Further, in the present specification, the "transparent resin layer containing a polypropylene resin" may be referred to as a "transparent resin layer", and the "base material layer containing a polypropylene resin" may be referred to as a "base material layer". be. Further, in the present specification, the notation of "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 the decorative sheet 100 of the present invention.
The decorative sheet 100 of FIG. 1 has a surface protective layer 10, a transparent resin layer 20 containing a polypropylene-based resin, and a base material layer 40 containing a polypropylene-based resin in this order. Further, the surface protective layer 10 of the decorative sheet 100 of FIG. 1 is composed of a top coat layer 11 and a primer layer 12. Further, the decorative sheet 100 of FIG. 1 has a decorative layer 30 between the base material layer 40 and the transparent resin layer 20.

<Asorbance>
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 large absorbance A1 means that there is little light having a wavelength of 270 nm to 300 nm that reaches the layer containing the polypropylene resin (transparent resin layer) located on the side close to the surface protective layer, and a large absorbance A2 means that the amount of light reaches the layer (transparent resin layer). This means that there is little light having a wavelength of 270 nm to 300 nm that reaches the layer (base material layer) containing the polypropylene-based resin located on the side far from the surface protective layer.
Conventional decorative sheets are usually designed to add an ultraviolet absorber only to the surface protective layer (top coat layer or primer layer). That is, the conventional decorative sheet has been designed only for the absorbance A1. However, in the design of only the absorbance A1, there is a limit to the improvement of the weather resistance of the decorative sheet. That is, although there are differences in the ease of bleeding out depending on the type of the ultraviolet absorber, all of them are lost over time due to bleeding out from the inside of the layer to the outside of the layer, and the concentration thereof decreases. Therefore, although the deterioration of the layer located inside the surface protective layer due to ultraviolet rays could be suppressed in the short term, it could not be suppressed over a long period of time. Generally, weather resistance is evaluated by the time required for deterioration of the entire decorative sheet due to ultraviolet rays to reach a predetermined degree assumed in advance in a state of being exposed to sunlight including ultraviolet rays. Therefore, there is a limit to the improvement of weather resistance in the design in which only the absorbance A1 of the surface protective layer is increased. In addition, in anticipation of bleeding out of the UV absorber over time, a design may be considered in which the weather resistance is improved by adding an extra amount of the UV absorber in the surface protective layer. In that case, the UV absorber Physical properties such as scratch resistance and stain resistance of the surface protective layer due to excessive addition are deteriorated, and there are problems such as appearance deterioration such as white turbidity of the surface due to bleeding out of an excessive amount of ultraviolet absorber.
Therefore, in the present invention, an ultraviolet absorber is added not only to the surface protective layer but also to the transparent resin layer to set two types of absorbances (absorbance A1 and absorbance A2) in a specific range to provide long-term weather resistance. While solving the problem, it makes it difficult for bleed-out to occur.

Polypropylene resin is significantly deteriorated by ultraviolet rays of 270 nm to 300 nm. Therefore, by blending an ultraviolet absorber that blocks ultraviolet rays in the specific wavelength range, long-term durability can be imparted to the decorative sheet using the polypropylene-based resin.

Absorbance A1 needs to be 0.6 or more. When the absorbance A1 is less than 0.6, the transparent resin layer containing the polypropylene-based resin and the base material layer containing the polypropylene-based resin deteriorate with time due to ultraviolet rays, and the weather resistance of the decorative sheet cannot be improved.
The absorbance is preferably 0.7 or more, more preferably 0.8 or more.

Further, the absorbance A1 is preferably 5.0 or less from the viewpoint of suppressing bleed-out.
A large absorbance A1 means that the content of the ultraviolet absorber in the surface protective layer is high, or that the film thickness of the surface protective layer is large. When the content of the ultraviolet absorber in the surface protective layer is high, the scratch resistance of the bleed-out and the surface protective layer tends to decrease, and when the film thickness of the surface protective layer is thick, the processability of the decorative sheet decreases. Tend. That is, when the absorbance A1 exceeds 5.0, any of the defects selected from the bleed-out of the ultraviolet absorber, the decrease in scratch resistance, and the decrease in processability are 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.

Absorbance A2 needs to be 1.2 or more. When the absorbance A2 is less than 1.2, the base material layer containing the polypropylene-based resin deteriorates with time due to ultraviolet rays, and the weather resistance of the decorative sheet cannot be improved.
The absorbance A2 is preferably 1.3 or higher, more preferably 1.4 or higher.

Further, 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 absorber tends 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.

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.

Absorbance A2 is an average value of absorbance measured at a wavelength of 270 nm to 300 nm of a laminate having a surface protective layer formed on a transparent resin layer in accordance with JIS K0115: 2004. In the present specification, the average value of the absorbances at wavelengths of 270 nm to 300 nm is the average value when the absorbances (total of 31 absorbances) are measured for each 1 nm for wavelengths of 270 nm to 300 nm.
Absorbance A1 is obtained by measuring the absorbance A0 of the transparent resin layer at a wavelength of 270 nm to 300 nm in accordance with JIS K0115: 2004 and subtracting the absorbance A0 from the absorbance A2 (absorbance A1 = absorbance A2-absorbance A0). .. The absorbance A0 is an average value of the absorbances measured at a wavelength of 270 nm to 300 nm of the transparent resin layer.

<Surface protective layer>
The surface protective layer is a layer located on the surface of the transparent resin layer opposite to the base material 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 the present specification, the layer of the surface protective layer farthest from the transparent resin layer is referred to as a "top coat layer". That is, when the surface protective layer is formed from a single layer, the surface protective layer has a single layer structure of the top coat layer. 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 is a layer other than the top coat layer among the layers constituting the surface protective layer. It means that there is.
The top coat layer preferably contains a cured product of the curable resin composition.
The surface protective layer preferably has a primer layer located closer to the transparent resin layer than the top coat layer. By forming the surface protection layer from the top coat layer and the primer layer and containing the ultraviolet absorber in both the top coat layer and the primer layer, the bleed-out of the ultraviolet absorber is suppressed while suppressing the deterioration with time due to the ultraviolet rays. Can be easily suppressed.

The surface protective layer is mainly composed of 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 nm to 300 nm reaching the transparent resin layer is sufficiently restricted by defining the absorbance A1, but the surface protective layer has a larger amount of light having a wavelength of 270 nm to 270 nm than the transparent resin layer. Light of 300 nm has arrived. Therefore, it is preferable that the polypropylene-based resin is not substantially contained as the resin constituting the surface protective layer, so that the weather resistance of the surface protective layer can be easily improved.
The fact that the polypropylene-based resin is substantially not contained means that the proportion of the polypropylene-based resin is 1% by mass or less, preferably 0.1% by mass or less, based on the total resin components constituting the surface protective layer. , More preferably 0.01% by mass or less, still more preferably 0% by mass.

《UV absorber》
It is preferable that at least one of the surface protective layer and the transparent resin layer contains an ultraviolet absorber, and it is more preferable that both the surface protective layer and the transparent resin layer contain an ultraviolet absorber.
When the surface protective layer is formed from 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 the layers constituting the surface protective layer contain an ultraviolet absorber.
Unless otherwise specified, the following embodiments relating to the ultraviolet absorber are common to the ultraviolet absorber of the surface protective layer and the ultraviolet absorber of the transparent resin layer.

Examples of the ultraviolet absorber include a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a triazine-based ultraviolet absorber, and the like, and a triazine-based ultraviolet absorber is preferable. Further, among the triazine-based ultraviolet absorbers, the hydroxyphenyltriazine-based ultraviolet absorber is preferable from the viewpoint of weather resistance performance.
That is, it is preferable that the decorative sheet of the present invention contains a triazine-based ultraviolet absorber in at least one of the surface protective layer and the transparent resin layer. Further, it is more preferable that the decorative sheet of the present invention contains a hydroxyphenyltriazine-based ultraviolet absorber in at least one of the surface protective layer and the transparent resin layer.
Further, an ultraviolet absorber having a reactive functional group such as a (meth) acryloyl group, a vinyl group or an allyl group is preferable because it is easy to suppress bleed-out.

Examples of the hydroxyphenyltriazine-based ultraviolet absorber include those of the following general formula (1).

In the general formula (1), R ¹¹ is a divalent organic group, R ¹² is an acyloxy group represented by −OC (= O) R ¹⁵ ^{, and R 13} , R ¹⁴ and R ¹⁵ are independent of each other. It is a hydrogen atom or a monovalent organic group, and n ₁₁ and n ₁₂ are independently integers of 0 to 5. Further, ^{when there are a plurality of R 13} and R ¹⁴ , they may be the same or different.
Examples of the divalent organic group of R ¹¹ include aliphatic hydrocarbon groups such as an alkylene group and an alkaneylene group. From the viewpoint of weather resistance, an alkylene group is preferable, and the number of carbon atoms thereof is preferably 1 or more, more preferably 1. It is 2 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, still more preferably 8 or less, and particularly preferably 4 or less. These aliphatic hydrocarbon groups may be linear, branched or cyclic, and are preferably linear or branched from the viewpoint of weather resistance, and more preferably linear.

R ¹³ and R ¹⁴ are preferably hydrogen atoms from the viewpoint of weather resistance. When R ¹³ and R ¹⁴ are monovalent organic groups, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an arylalkyl group and the like are preferably mentioned, and an aryl group and an arylalkyl group are preferably mentioned from the viewpoint of weather resistance. The aromatic hydrocarbon group such as, etc. is preferable, and an aryl group, particularly a phenyl group, is preferable.
R ¹⁵ is preferably a monovalent organic group from the viewpoint of weather resistance, preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an arylalkyl group or the like, and from the viewpoint of weather resistance, an alkyl group or an alkenyl group. Such as an aliphatic hydrocarbon group is more preferable, and an alkyl group is further preferable. A monovalent organic group is an alkyl group of R ^15, when the aliphatic hydrocarbon group such as an alkenyl group, a linear, branched, or cyclic, linear from the viewpoint of weather resistance, branching The shape is preferable, and the number of carbon atoms thereof is preferably 2 or more, more preferably 4 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, still more preferably 10 or less, from the viewpoint of weather resistance.

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

Further, examples of the hydroxyphenyltriazine-based ultraviolet absorber include those having the following general formula (2).
Since the hydroxyphenyltriazine compound represented by the general formula (2) does not contain an ester bond in the molecule, the molecular structure is not easily displaced. Therefore, the hydroxyphenyltriazine compound represented by the general formula (2) is preferable to the hydroxyphenyltriazine compound represented by the general formula (1) in that it is superior in suppressing bleed-out and maintaining long-term weather resistance.
It is considered that the variation in the molecular structure starting from the ester bond is caused by the acidic condition. Therefore, the hydroxyphenyltriazine compound represented by the general formula (2) can exert an excellent effect when used outdoors exposed to acid rain.

In the general formula (2), R ²¹ is a monovalent organic group, R ²¹ is a hydrogen atom or a monovalent organic group, and R ²² and R ²³ are independently hydroxyl groups or monovalent organic groups. Yes, n ₂₁ , n ₂₂ and n ₂₃ are independently integers from 1 to 5. Further, ^{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. , An aliphatic hydrocarbon group such as an alkyl group or an alkenyl group is more preferable, and an alkyl group is further preferable. In this case, the ^{monovalent organic groups of R 21} , R ²² and R ²³ may be linear, branched or cyclic, and are preferably linear or branched from the viewpoint of weather resistance, and are straight. Chain form is more preferable. 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, still more preferably 8 or less.
Further, n ₂₁ , n ₂₂ and n ₂₃ are preferably 2 or more, and a plurality of R ²¹ , R ²² and R ²³ may be the same or different, and the plurality of R ^21s are the same from the viewpoint of weather resistance. It is preferable that R ²² and R ²³ are different. It is preferable that one of the different R ²² and R ^{23 is a hydrogen atom.} When R ²¹ , R ²² and R ²³ are monovalent organic groups, they are preferably the same organic group.

Specific examples of the hydroxyphenyltriazine-based ultraviolet absorber of the general formula (2) include those of the following general formula (2-1). The hydroxyphenyltriazine-based ultraviolet absorber of the 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 setting the content of the ultraviolet absorber in the surface protective layer to a predetermined amount or more, the absorbance A1 can be easily set to 0.6 or more. Further, by setting the content of the ultraviolet absorber in the surface protective layer to a predetermined amount or less, bleed-out can be easily suppressed.
The content of the ultraviolet absorber in the top coat layer constituting the surface protective layer is preferably 0.5 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the resin constituting the top coat layer, and is 1.0. It is more preferably parts by mass or more and 8.0 parts by mass or less, further 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.
When the other layer constituting the surface protective layer contains an ultraviolet absorber, the content of the ultraviolet absorber in the other layer is 1 part by mass with respect to 100 parts by mass of the resin constituting the other layer. It is preferably 40 parts by mass or less, more preferably 5 parts by mass or more and 30 parts by mass or less, and further preferably 7 parts by mass or more and 25 parts by mass or less. Examples of the other layer include a primer layer.

《Radical scavenger》
At least one of the surface protective layer and the transparent resin layer preferably contains a radical scavenger. Since the surface protective layer is the layer to which ultraviolet rays are first incident among the layers constituting the decorative sheet, it is preferable to contain 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.
Unless otherwise specified, the following embodiments relating to the radical scavenger are common to the radical scavenger of the surface protective layer and the radical scavenger of the transparent resin layer.

Examples of the radical scavenger include aromatic radical scavengers, amine radical scavengers, organic acid radical scavengers, catechin radical scavengers and hindered amine radical scavengers. preferable. The hindered amine radical scavenger has a structure containing a 2,2,6,6-tetramethylpiperidine skeleton in the molecule.

When the surface protective layer contains a radical scavenger, the radical scavenger is polymerized with the radical scavenger i having an ethylenic double bond polymerizable with the resin constituting the surface protective layer and the resin constituting the surface protective layer. It preferably contains a radical scavenger ii that does not have a possible ethylenic double bond.
The ethylenic double bond has, for example, a functional group such as a (meth) acryloyl group, a vinyl group and an allyl group.

When only the radical scavenger i is used, almost all the radical scavengers in the surface protective layer are in an immobilized state, and there is almost no radical scavenger that can move freely in the surface protective layer, so that the radicals are captured. It becomes difficult for the performance to be exhibited. On the other hand, since the radical trapping agent i polymerizes with the resin constituting the surface protective layer, when the resin constituting the surface protective layer contains a cured product (particularly a cured product of the ionizing radiation curable resin composition), the radical trapping agent i As a result, the crosslink density of the cured product (particularly the cured product of the ionizing radiation curable resin composition) decreases, and the scratch resistance tends to decrease.
On the other hand, when only the radical scavenger ii is used, the radical scavenger ii tends to bleed out from the surface protective layer over time, so that the appearance of the decorative sheet surface is deteriorated and the ability to capture radicals is maintained for a long period of time. It becomes difficult to maintain.
Therefore, it is preferable that the surface protective layer contains the radical scavenger i and the radical scavenger ii from the viewpoints of radical scavenging property, 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 a radical scavenger i and a radical scavenger ii.

The blending ratio of the radical scavenger i and the radical scavenger ii based on the mass is preferably 8: 2 to 2: 8.
By setting the radical scavenger i to 8 and the radical scavenger ii to 2 or more, the weather resistance can be improved and the decrease in the crosslink density of the cured product of the surface protective layer can be easily suppressed. Further, by setting the radical scavenger i to 8 or less with respect to the radical scavenger i 2, it is possible to easily suppress the bleed-out of the radical scavenger ii.

The content of the radical scavenger in the topcoat layer constituting the surface protective layer is preferably 0.5 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the resin constituting the topcoat layer, and is preferably 1 part by mass or more and 8 parts by mass. It is more preferably parts by mass or less, and further preferably 1.5 parts by mass or more and 5 parts by mass or less.
When the other layer constituting the surface protective layer contains a radical scavenger, the content of the radical scavenger in the other layer is 0.1 with respect to 100 parts by mass of the resin constituting the other layer. It is preferably 5 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 further preferably 1 part by mass or more and 5 parts by mass or less.

The radical scavenger i has an ethylenic double bond that can be polymerized with the resin constituting 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 preferable. That is, the radical scavenger i preferably has a (meth) acryloyl group.
The number of ethylenic double bonds in the radical scavenger i is not particularly limited, and may be one or two or more. Further, only one type of radical scavenger i may be used, or two or more types may be used.

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

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

Examples of the radical trapping agent ii include 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidyl) sevacate, and bis (1,2,2). , 6,6-Pentamethyl-4-piperidyl) benzylate, bis (1-octyl oshiki-2,2,6,6-tetramethyl-4-piperidinyl) benzylate, bis (1,2,2,6,6-pentamethyl- 4-Piperidinyl) sevacate, methyl (1,2,2,6,6-pentamethyl-4-piperidinyl) sevakate, 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 and the like.

《Top coat layer》
The top coat layer preferably contains a cured product of the curable resin composition in order to enhance the scratch resistance of the decorative sheet.
Further, the ratio of the cured product of the curable resin composition to the total resin components constituting the top coat layer is preferably 50% by mass or more, more preferably 70% by mass or more, and 80% by mass. The above is more preferable.

Examples of the cured product of the curable resin include a cured product of a thermosetting resin, a cured product of an ionization radiation curable resin, and a mixture thereof. Among these, a cured product of an ionizing radiation curable resin composition is preferable from the viewpoint of increasing the crosslink density of the top coat layer and improving scratch resistance and weather resistance. Further, from the viewpoint of being able to be applied without a solvent and being easy to handle, the cured product of the electron beam curable resin composition is more preferable among the ionizing radiation curable resin compositions.

The thermosetting resin composition is a composition containing at least a thermosetting resin, and is a resin composition that is cured by heating. Examples of the thermosetting resin include acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin. In the thermosetting resin composition, a curing agent is added to these curable resins as needed.

-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 “ionizing radiation curable compound”). The ionizing radiation curable functional group is a group that is crosslinked and cured by irradiation with ionizing radiation, and preferably includes a functional group having an ethylenic double bond such as a (meth) acryloyl group, a vinyl group, and an allyl group.
Further, ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking a molecule, and usually, ultraviolet rays (UV) or electron beams (EB) are used. Electromagnetic waves such as X-rays and γ-rays, and charged particle rays such as α-rays and ion rays are also included.
Specifically, the ionizing radiation curable compound can be appropriately selected and used from the polymerizable monomers and polymerizable oligomers conventionally used as ionizing radiation curable resins.

As the polymerizable monomer, a (meth) acrylate-based monomer having a radically polymerizable unsaturated group in the molecule is preferable, and a polyfunctional (meth) acrylate monomer is particularly preferable. Here, "(meth) acrylate" means "acrylate or methacrylate".
Examples of the polyfunctional (meth) acrylate monomer include 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 2 or more and 8 or less, more preferably 2 or more and 6 or less, and further preferably 2 or more and 4 or less. More preferably 2 or more and 3 or less. These polyfunctional (meth) acrylates may be used alone or in combination of two or more.

Examples of the polymerizable oligomer include a (meth) acrylate oligomer having two or more ionizing radiation-curable functional groups in the molecule and having at least a (meth) acryloyl group as the functional group. For example, urethane (meth) acrylate oligomer, epoxy (meth) acrylate oligomer, polyester (meth) acrylate oligomer, polyether (meth) acrylate oligomer, polycarbonate (meth) acrylate oligomer, acrylic (meth) acrylate oligomer and the like can be mentioned.
Further, as the polymerizable oligomer, a highly hydrophobic polybutadiene (meth) acrylate-based oligomer having a (meth) acrylate group in the side chain of the polybutadiene oligomer, and a silicone (meth) acrylate-based oligomer having a polysiloxane bond in the main chain. In molecules such as aminoplast resin (meth) acrylate-based oligomers modified from aminoplast resins having many reactive groups in small molecules, novolak type epoxy resins, bisphenol type epoxy resins, aliphatic vinyl ethers, aromatic vinyl ethers, etc. There are oligomers and the like having cationically polymerizable functional groups.

These polymerizable oligomers may be used alone or in combination of two or more. Urethane (meth) acrylate oligomer, epoxy (meth) acrylate oligomer, polyester (meth) acrylate oligomer, polyether (meth) acrylate oligomer, polycarbonate (meth) acrylate oligomer from the viewpoint of improving processing properties, scratch resistance and weather resistance. , Acrylate (meth) acrylate oligomers are preferable, urethane (meth) acrylate oligomers and polycarbonate (meth) acrylate oligomers are more preferable, and urethane (meth) acrylate oligomers are even more preferable.

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

A monofunctional (meth) acrylate can be used in combination with the ionizing radiation curable resin composition 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.

The thickness of the top coat 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 further preferably 3 μm or more and 10 μm or less from the viewpoint of the balance between processing characteristics, scratch resistance and weather resistance.

《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 top coat layer in addition to the top coat layer. The primer layer can improve the adhesion between the top coat 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.
As the binder resin, urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, polycarbonate-based urethane-acrylic copolymer (carbonate bond to the polymer main chain). Urethane-acrylic copolymer derived from a polymer (polycarbonate polyol) having two or more hydroxyl groups at the end and side chains), vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic common weight Resins such as a coalesced resin, a chlorinated propylene resin, a nitrocellulose resin (nitrified cotton), and a cellulose acetate resin are preferably mentioned, and these can be used alone or in combination of two or more. 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 further 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 base material layer.
The content of the polypropylene-based resin in the transparent resin layer is preferably 50% by mass or more, more preferably 60% by mass or more, based on the total resin components of the transparent resin layer, from the viewpoint of processability. It is preferably 70% by mass or more, and more preferably 70% by mass or more.

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

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

As described above, the transparent resin layer preferably contains an ultraviolet absorber and a radical scavenger.
The content of the ultraviolet absorber in the transparent resin layer is not particularly limited as long as the absorbance A2 is 1.2 or more.
When the thickness of the transparent resin layer is in the range described later, the content of the ultraviolet absorber in the transparent resin layer is 0.05 part by mass or more with respect to 100 parts by mass of the resin constituting the transparent resin layer. It is preferably 10 parts by mass or less, more preferably 0.07 parts by mass or more and 5 parts by mass or less, further preferably 0.09 parts by mass or more and 3 parts by mass or less, and further preferably 0.10 parts by mass or more and 1 part by mass or less.
When the thickness of the transparent resin layer is in the range described later, the content of the radical trapping agent in the transparent resin layer is 0.1 part by mass or more with respect to 100 parts by mass of the resin constituting the transparent resin layer. It is preferably 10 parts by mass or less, more preferably 0.5 parts by mass or more and 8 parts by mass or less, further preferably 1 part by mass or more and 5 parts by mass or less, and further preferably 1.5 parts by mass or more and 3 parts by mass or less.

The transparent resin layer may be transparent to the extent that the base material layer side can be visually recognized from the transparent resin layer, and may be colorless and transparent, as well as colored transparent and translucent.

The thickness of the transparent resin layer is preferably 20 μm or more and 150 μm or less, more preferably 40 μm or more and 120 μm or less, and further preferably 60 μm or more and 100 μm or less, from the viewpoint of the balance between scratch resistance, processing suitability and weather resistance.
Further, the thickness of the transparent resin layer is preferably thicker than that of the base material layer from the viewpoint of protecting the decorative layer and obtaining excellent scratch resistance.

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

Examples of the polypro-based resin of the base material layer include polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-butene copolymer and the like. Among these, polypropylene, ethylene-propylene copolymer, and propylene-butene copolymer are preferable, and polypropylene is more preferable.

When the base material layer contains a resin other than the polypropylene resin, for example, a polyolefin resin other than the polypropylene resin (polyethylene, polymethylpentene, polybutene, etc.), a polyester resin, a polycarbonate resin, and an acrylonitrile-butadiene-styrene resin (hereinafter, A thermoplastic resin such as "ABS resin"), acrylic resin, vinyl chloride resin and the like can be used.

The base material layer may be colorless and transparent, but is preferably colored from the viewpoint of designability.
When coloring the base material layer, a colorant such as a dye or a pigment can be added to the base material layer. Among these colorants, pigments that easily suppress fading are preferable.
As pigments, white pigments such as zinc flower, white lead, lithopone, titanium dioxide, precipitated barium sulfate and barite; black pigments such as carbon black; red pigments such as lead tan and iron oxide red;
Yellow pigments such as chrome yellow and zinc yellow (1 type of zinc yellow and 2 types of zinc yellow); blue pigments such as ultramarine blue and prussian blue (potassium ferrocyanide); and the like can be mentioned.

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, and 5 parts by mass or more and 30 parts by mass with respect to 100 parts by mass of the resin constituting the base material layer. More preferably, it is 5 parts by mass or less, and further preferably 5 parts by mass or more and 20 parts by mass or less.

Additives may be added to the base material layer, if necessary. Examples of the additive include an inorganic filler such as calcium carbonate and clay, a flame retardant such as magnesium hydroxide, an antioxidant, a lubricant, a foaming agent, an ultraviolet absorber, and a radical scavenger. The blending amount of the additive can be appropriately adjusted as long as the effect of the present invention is not impaired.
In the present invention, since the absorbances A1 and A2 are within a predetermined range, it is preferable in that the weather resistance of the base material layer can be improved without containing an ultraviolet absorber and a radical scavenger in the base material layer. be.

The thickness of the base material layer is preferably 20 μm or more and 150 μm or less, more preferably 25 μm or more and 120 μm or less, further preferably 30 μm or more and 100 μm or less, still more preferably 40 μm or more and 80 μm or less, from the viewpoint of the balance between designability and processability.

In order to improve the adhesion of the base material layer to other layers of the decorative sheet and the adherend, one or both sides of the base material layer may be physically surface-treated by an oxidation method, an unevenness method, or a chemical surface. Surface treatment such as treatment may be performed, 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 on the decorative sheet. The portion where the decorative layer is formed is preferably between the base material layer and the transparent resin layer from the viewpoint of enhancing the weather resistance of the decorative layer.

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

The ink used for the decorative layer is a binder resin mixed with a pigment, a colorant such as a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, an ultraviolet absorber, a radical scavenger, etc. as appropriate. used.
The binder resin of the decorative layer is not particularly limited, and for example, urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, vinyl chloride-vinyl acetate common weight. Examples thereof include a coalesced resin, a vinyl chloride-vinyl acetate-acrylic copolymer resin, a chlorinated propylene resin, a nitrocellulose resin, and a cellulose acetate resin. Further, various types of resins such as a one-component curable resin and a two-component curable resin with a curing agent such as an isocyanate compound can be used.

As the colorant, a pigment having excellent hiding power and weather resistance is preferable. As the pigment, the same pigment as those exemplified in the base material layer can be used.
The content of the colorant in the base material 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 30 parts by mass with respect to 100 parts by mass of the resin constituting the decorative layer. More than 70 parts by mass is more preferable.

From the viewpoint of improving weather resistance, the decorative layer preferably contains a weather resistant agent such as an ultraviolet absorber and a radical scavenger.

The thickness of the decorative layer may be appropriately selected according to the desired pattern, but from the viewpoint of hiding the ground color of the adherend and improving the design, it is preferably 0.5 μm or more and 20 μm or less, and 1 μm or more and 10 μm. The following is more preferable, and 2 μm or more and 5 μm or less is further preferable.

<Adhesive layer A>
It is preferable to form an adhesive layer A between the base material layer and the transparent resin layer in order to improve the adhesion between the two layers.
When the above-mentioned decorative layer is further provided between the base material 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 material layer, or the adhesive layer A and the decorative layer may be provided in order from the side closer to the base material layer. good.

The adhesive layer A can be composed of, for example, an adhesive such as a urethane-based adhesive, an acrylic-based adhesive, an epoxy-based adhesive, or a rubber-based adhesive. Among these adhesives, urethane-based adhesives are preferable in terms of adhesive strength.
Examples of urethane-based adhesives include adhesives using a two-component curable urethane resin containing various polyol compounds such as polyether polyols, polyester polyols, and acrylic polyols and curing agents such as the above-mentioned various isocyanate compounds. Be done.

The thickness of the 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 further preferably 2 μm or more and 10 μm or less.

The above-mentioned decorative layer, adhesive layer A, primer layer and top coat layer are coated with a coating liquid containing a composition forming each layer by a gravure printing method, a bar coating method, a roll coating method, a reverse roll coating method, or a comma coating method. It can be formed by applying it by a known method such as, and if necessary, drying and curing it.

The decorative sheet of the present invention may be provided with irregularities by embossing or the like.
When embossing, for example, the decorative sheet is heated to preferably 80 ° C. or higher and 260 ° C. or lower, more preferably 100 ° C. or higher and 220 ° C. or lower, and further preferably 120 ° C. or higher and 200 ° C. or lower, and the embossing plate is pressed against the decorative sheet. Then, embossing can be performed. The portion where the embossed plate is pressed is preferably on the surface protective layer side of the decorative sheet.

[Cosmetic material]
The decorative material of the present invention has an adherend and the above-mentioned decorative sheet of the present invention. Specifically, a surface requiring decoration of the adherend and a surface of the decorative sheet on the base material layer side. Are laminated so as to face each other.

<Adhesion material>
Examples of the adherend include flat plates of various materials, plate materials such as curved plates, three-dimensional articles, sheets (or films), and the like. Examples of the material of the adherend include wood members, metal members, ceramic members, resin members and the like.
Examples of raw materials for wood members include various types of wood such as cedar, cypress, pine, and lauan. Examples of the shape of the wood member include wood veneer, wood plywood, particle board, wood fiber board such as MDF (medium density fiber board), and a three-dimensional article.
Examples of raw materials for metal members include iron and aluminum. Examples of the shape of the metal member include a plate material, a steel plate, a three-dimensional article, and a sheet.
Examples of raw materials for ceramic components include ceramics such as glass and ceramics, non-cement ceramic materials such as gypsum, and non-ceramic ceramic materials such as ALC (lightweight cellular concrete) plates. Examples of the shape of the ceramic member include a plate material, a three-dimensional article, and the like.
As raw materials for resin members, polyolefin resins such as acrylic resin, polyester resin, polystyrene resin, polypropylene resin, ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenol resin, vinyl chloride resin, cellulose resin, rubber, etc. Can be mentioned. Examples of the shape of the resin member include a plate material, a three-dimensional article, and a sheet.
The members constituting the adherend can be used alone or in combination of two or more. The decorative material of the present invention is preferable in that the weather resistance of the adherend can be improved when the adherend contains a polypropylene resin.

The adherend may be appropriately selected from the above depending on the intended use.
When an adherend is used as an interior or exterior member of a building such as a wall, ceiling, or floor; a fitting or a structure member such as a window frame, a door, a handrail, a skirting board, a peripheral edge, or a mall; The material of the landing material is preferably at least one selected from a wood member, a metal member and a resin member. When an adherend is used as an exterior member such as an entrance door, a window frame, or a fitting such as a door, the material of the adherend is preferably at least one selected from a metal member and a resin member. ..

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

<Adhesive layer B>
The adherend and the decorative sheet are preferably bonded together via the adhesive layer B in order to obtain excellent adhesiveness.

The adhesive used for the adhesive layer B is not particularly limited, and known adhesives can be used. For example, adhesives such as heat-sensitive adhesives and pressure-sensitive adhesives are preferable. Examples of the resin used for the adhesive constituting the adhesive layer include acrylic resin, polyurethane resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, styrene-acrylic copolymer resin, and polyester resin. , Polyamide resin and the like, and these can be used alone or in combination of two or more. Further, a two-component curable polyurethane-based adhesive or a polyester-based adhesive using an isocyanate compound or the like as a curing agent can also be applied.
Further, an adhesive may be used for the adhesive layer B. As the pressure-sensitive adhesive, an acrylic-based, urethane-based, silicone-based, rubber-based, or other pressure-sensitive adhesive can be appropriately selected and used.

The thickness of the adhesive layer B is not particularly limited, but from the viewpoint of obtaining excellent adhesiveness, it is preferably 1 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less, and further preferably 10 μm or more and 30 μm or less.

Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to this example.

1. 1. Evaluation and measurement 1-1. Absorbance A laminate in which a surface protective layer is formed on a transparent resin layer in accordance with JIS K0115: 2004 using an ultraviolet-visible near-infrared spectrophotometer (manufactured by Hitachi, Ltd., trade name: U-4000). The absorbance A2 having a wavelength of 270 nm to 300 nm was measured and the average value was calculated. Further, the absorbance A0 at a wavelength of 270 nm to 300 nm of the transparent resin layer was measured by the same means, and the absorbance A0 at a wavelength of 270 nm to 300 nm of the surface protective layer was calculated by subtracting the absorbance A0 from the absorbance A2.

1-2. Weather resistance After irradiating the decorative sheets obtained in Examples and Comparative Examples with ultraviolet rays for 20 hours under the conditions of a black panel temperature of 63 ° C. and an illuminance of 100 mW / cm ^{2, using the following super-accelerated weather resistance test apparatus.} The cycle of dew condensation was repeated for 4 hours. After 1000 hours and 1400 hours, the appearance of the decorative sheet was visually evaluated according to the following criteria.
<Ultra-accelerated weather resistance test equipment>
UV lamp (trade name: M04-L21WB / SUV, manufactured by Iwasaki Electric Co., Ltd.), lamp jacket (trade name: WJ50-SUV, manufactured by Iwasaki Electric Co., Ltd.) and illuminance meter (trade name: UVD-365PD, manufactured by Iwasaki Electric Co., Ltd.) Super accelerated weather resistance test equipment (trade name: Eye Super UV Tester SUV-W161 ", manufactured by Iwasaki Electric Co., Ltd.)
<Evaluation criteria>
A: No change in appearance was confirmed on the entire decorative sheet.
B: A slight whitening was confirmed on the appearance of the decorative sheet, but a change in color tone of the transparent resin layer and / or the base material layer could not be confirmed.
C: A slight whitening was confirmed on the appearance of the decorative sheet, and a slight change in color tone of the transparent resin layer and / or the base material layer was confirmed.
D: Remarkable whitening of the appearance of the decorative sheet and a large change in color tone of the transparent resin layer and / or the base material layer were confirmed.

1-3. Bleedout The decorative sheets obtained in Examples and Comparative Examples were immersed in a constant temperature bath of 60 ° C. hot water for 1 week, then taken out and sufficiently dried, and then visually and non-contact shape analysis laser microscope (manufactured by KEYENCE: VK). The appearance was observed using -X1000) and evaluated according to the following criteria.
A: No change in appearance was confirmed.
B: Appearance changes such as slight swelling, air bubbles, gloss change, and precipitation of sheet components were confirmed.
C: Appearance changes such as remarkable swelling, air bubbles, gloss change, and precipitation of sheet components were confirmed.

2. Preparation of decorative sheet [Example 1]
A decorative layer was formed on one surface of a base material layer (colored polypropylene resin sheet having a thickness of 60 μm) subjected to double-sided corona discharge treatment using a printing ink made of a two-component curable acrylic-urethane resin. Next, an adhesive layer made of a urethane resin-based adhesive having a thickness of 3 μm was formed on the decorative layer.
Next, on the adhesive layer, 0.12 parts by mass of a hydroxyphenyltriazine-based ultraviolet absorber (trade name: TINUVIN479, manufactured by BASF) and a hydroxyphenyltriazine-based ultraviolet absorber (trade name: TINUVIN479, manufactured by BASF) were added to 100 parts by mass of the polypropylene-based resin. A composition A containing 0.12 parts by mass of (trade name: ADEKA STUB LA-46, manufactured by ADEKA) was heated, melted and extruded by a T-die extruder to form a transparent resin layer having a thickness of 80 μm.
After the surface of the transparent resin layer was subjected to a corona discharge treatment, the following composition B was applied and dried on the transparent resin layer to form a primer layer having a thickness of 4 μm.
<Composition B>
100 parts by mass of composition X (a composition in which a composition composed of a polycarbonate urethane-acrylic copolymer and an acrylic polyol and hexamethylene diisocyanate are mixed at a mass ratio of 100: 5) and 10 parts by mass of hydroxy A composition obtained by mixing a phenyltriazine-based ultraviolet absorber (trade name: TINUVIN400, manufactured by BASF).

Next, the following composition C was applied onto the primer layer and irradiated with an electron beam to cure the ionizing radiation curable resin composition to form a topcoat layer having a thickness of 5 μm.
Next, a wood grain conduit-like uneven pattern having a depth of 50 μm was formed from above the top coat layer by embossing to obtain a decorative sheet of Example 1.

<Composition C>
100 parts by mass of ionizing radiation curable resin composition (trifunctional urethane acrylate oligomer having a weight average molecular weight of 4000)
-Hydroxyphenyltriazine UV absorber 1 part by mass (trade name: TINUVIN1600, manufactured by BASF)
-Hydroxyphenyltriazine UV absorber 2 parts by mass (trade name: TINUVIN479, manufactured by BASF)
-Hindered amine radical scavenger i with an ethylenic double bond capable of reacting with an ionizing radiation curable resin i 1.5 parts by mass (pentamethylpiperidinyl methacrylate)
-Hindered amine radical scavenger that does not have an ethylenic double bond that can react with an ionizing radiation curable resin ii 3.0 parts by mass (bis (1-octyloxy-2,2,6,6-tetramethyl-4-) Piperidinil) Sevacate)

[Examples 2 to 5], [Comparative Examples 1 to 4], [Reference Example 1]
Examples 2 to 5 and Comparative Examples 1 to 4 are the same as in Example 1 except that the ultraviolet absorber of the transparent resin layer and the ultraviolet absorber of the top coat layer are changed to those in Table 1. And the decorative sheet of Reference Example 1 was obtained.

* 1: In Table 1, "UVA-i to UVA-v" are all "hydroxyphenyltriazine-based ultraviolet absorbers".
* 2: In Table 1, "UVA-i" is "BASF's product name TINUVIN1600", "UVA-ii" is "BASF's product name TINUVIN479", and "UVA-iii" is "ADEKA". "LA-46" and "UVA-iv" indicate the product name TINUVIN405 manufactured by BASF, and "UVA-v" indicates the product name TINUVIN400 manufactured by BASF.
* 3: In Table 1, the UVA content means the content of each UV absorber (unit is "parts by mass") with respect to 100 parts by mass of the resin of each layer.

From the results in Table 1, it can be confirmed that the decorative sheet of the example having 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.

Since the decorative sheet of the present invention has excellent weather resistance, it is suitably used as a decorative sheet for members used in an environment exposed to direct sunlight, such as exterior members such as entrance doors, window frames, and fittings such as doors.

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

Claims

A surface protective layer, a transparent resin layer containing a polypropylene resin, and a base material layer containing a polypropylene resin are provided in this order, and the surface protective layer is measured in accordance with JIS K0115: 2004 at a wavelength of 270 nm to 300 nm. A decorative sheet having an absorbance A1 of 0.6 or more and an absorbance A2 of the surface protective layer and the transparent resin layer measured in accordance with JIS K0115: 2004 at wavelengths of 270 nm to 300 nm of 1.2 or more.
The decorative sheet according to claim 1, wherein at least one of the surface protective layer and the transparent resin layer contains a triazine-based ultraviolet absorber.
The decorative sheet according to claim 2, which contains the hydroxyphenyltriazine compound represented by the following general formula (I) as the triazine-based ultraviolet absorber.
The surface protective layer has a radical scavenger i having an ethylenic double bond that can be polymerized with the resin constituting the surface protective layer, and an ethylenic double bond that can be polymerized with the resin constituting the surface protective layer. The decorative sheet according to any one of claims 1 to 3, which comprises a radical scavenger ii that does not.
The decorative sheet according to any one of claims 1 to 4, which does not substantially contain a polypropylene-based resin as the resin constituting the surface protective layer.
The decorative sheet according to any one of claims 1 to 5, which has a top coat layer containing a cured product of a curable resin composition as the surface protective layer.
The decorative sheet according to claim 6, further comprising a primer layer located on the transparent resin layer side of the top coat layer as the surface protective layer.
The decorative sheet according to any one of claims 1 to 7, which has a decorative layer between the base material layer and the transparent resin layer.
A decorative material having an adherend and a decorative sheet according to any one of claims 1 to 8.