Transfer sheet and weather-resistant article

Abstract

To suppress lowering of adhesion between a surface protective layer and a primer layer for a long period of time in a transfer layer transferred onto a transferred body from a transfer sheet having the surface protective layer and the primer layer.SOLUTION: A transfer sheet has a releasable base material and a transfer layer, wherein the transfer layer has a surface protective layer and a primer layer, the surface protective layer is positioned between the releasable base material and the primer layer, and the surface protective layer contains a curable resin, a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a transfer sheet and a weather-resistant article.

Background Art

[0002] Conventionally, in order to impart scratch resistance, stain resistance, etc. to articles such as interior materials of buildings, exterior materials of buildings, furniture, architectural members, and household appliances, a surface protective layer is provided on the surface of the article. The surface protective layer is formed, for example, by coating or using a transfer sheet (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, exterior materials used outdoors may be placed in an environment exposed to direct sunlight, so it is desirable to have excellent weather resistance. However, when a surface protective layer is provided on the surface of a transfer body using the above-described transfer sheet, the weather resistance tends to be insufficient, such as peeling of the surface protective layer. A transfer sheet usually includes a transfer layer containing a surface protective layer and a primer layer. The present inventors have found that the reason for the insufficient weather resistance is due to the insufficient adhesion between the surface protective layer and the primer layer after being placed in an environment exposed to direct sunlight for a long time.

[0005] One problem of the present disclosure is to suppress a decrease in the adhesion between a surface protective layer and a primer layer for a long time in a transfer layer transferred from a transfer sheet including the transfer layer containing the surface protective layer and the primer layer to a transfer body.

Means for Solving the Problems

[0006] The transfer sheet of this disclosure comprises a release substrate and a transfer layer, the transfer layer comprising a surface protection layer and a primer layer, the surface protection layer being located between the release substrate and the primer layer, and the surface protection layer containing a curing resin, a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength. [Effects of the Invention]

[0007] According to this disclosure, in a transfer layer transferred to a substrate from a transfer sheet comprising a transfer layer including a surface protection layer and a primer layer, it is possible to suppress the deterioration of adhesion between the surface protection layer and the primer layer over a long period of time, for example, in an environment exposed to direct sunlight. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic cross-sectional view of one embodiment of the transfer sheet of the present disclosure. [Figure 2] Figure 2 is a schematic cross-sectional view of one embodiment of the transfer sheet of the present disclosure. [Figure 3] Figure 3 is a schematic cross-sectional view of one embodiment of the weather-resistant article of the present disclosure. [Modes for carrying out the invention]

[0009] The embodiments of this disclosure will be described in detail below. This disclosure can be implemented in many different forms and should not be construed as being limited to the embodiments described below. The drawings may schematically represent the width, thickness, and shape of each layer, etc., compared to the embodiments, in order to clarify the explanation, but these are merely examples and should not limit the interpretation of this disclosure. In this specification and in each figure, elements similar to those already described in the previously shown figures will be denoted by the same reference numerals, and detailed explanations may be omitted as appropriate.

[0010] Films and sheets are sometimes referred to as films and sheets, respectively, in order of increasing thickness. However, in this disclosure, unless otherwise specified, "sheet" encompasses "film."

[0011] In the following description, each component (for example, resin components, UV absorbers, light stabilizers, colorants, and additives) may be used individually or in combination of two or more types, unless otherwise specified.

[0012] The transfer sheet of this disclosure comprises a release substrate and a transfer layer. The transfer layer is provided in a removable manner on a release substrate. The transfer layer comprises a surface protection layer and a primer layer. The surface protection layer is located between the release substrate and the primer layer. The surface protection layer constitutes, for example, the surface layer on the release substrate side of the transfer layer. The transfer layer may further comprise an adhesive layer. The adhesive layer constitutes, for example, the surface layer on the side opposite to the release substrate side of the transfer layer. Therefore, the transfer layer may comprise the surface protection layer, primer layer and adhesive layer in this order.

[0013] In the transfer sheet of this disclosure, the transfer layer may further comprise other layers different from the surface protection layer, primer layer, and adhesive layer. Known layers, such as a design layer, can be appropriately selected and used as the other layers.

[0014] The surface protective layer contains a cured resin, a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength. Details of these ultraviolet absorbers will be described later. A weather-resistant article obtained by transferring the transfer layer from the transfer sheet of this disclosure to a transfer object can suppress the decrease in adhesion between the surface protective layer and the primer layer in an environment exposed to direct sunlight, and can maintain weather resistance for a long period of time in such an environment.

[0015] In weather-resistant articles comprising a primer layer and a surface protection layer, it is necessary to suppress the deterioration of the primer layer in order to maintain weather resistance over a long period of time. Therefore, the extent to which the surface protection layer can absorb ultraviolet light, which is considered one of the factors causing deterioration of the primer layer, is important. The Disclosers have found that a surface protection layer containing one or two types of ultraviolet absorbers may suppress the deterioration of the primer layer due to ultraviolet light in the short term, but may not sufficiently suppress deterioration due to ultraviolet light in the long term. This is presumed to be due to the following reasons. One of the factors contributing to the adhesion between the primer layer and the surface protection layer is the polymer component contained in the primer layer. When this polymer component degrades due to ultraviolet light, the primer layer itself becomes brittle, the adhesion between the primer layer and the surface protection layer weakens, and delamination is thought to occur at the interface between the primer layer and the surface protection layer. As a result, the weather resistance of the above-mentioned article decreases. For example, if the above-mentioned article is exposed to ultraviolet light for a long period of time, the degradation of the polymer component contained in the primer layer progresses gradually. In this case, for example, if one or two types of UV absorbers are added in large quantities to the surface protective layer, sufficient UV absorption can be achieved. However, in this case, problems may arise such as the bleeding out of the UV absorbers, poor adhesion between the surface protective layer and the primer layer, and a decrease in the transparency of the surface protective layer. To address these problems, the Disclosers have found that the long-term weather resistance of the article can be improved by including at least three types of ultraviolet absorbers in the surface protective layer, each with different absorption peak wavelengths. This is presumed to be due to the following reasons: By using three or more types of ultraviolet absorbers in combination, a wide range of ultraviolet wavelengths can be covered. This allows the ultraviolet absorbers to sufficiently absorb ultraviolet light across a wide range of wavelengths. Therefore, degradation of the primer layer due to ultraviolet light can be suppressed over a long period of time. As a result, the article can maintain its weather resistance for a sufficiently long period of time in environments exposed to direct sunlight. Furthermore, since degradation of the transfer material itself can also be suppressed, the transfer sheet of this disclosure can be applied to various transfer materials.

[0016] Figures 1 and 2 show the configuration of one embodiment of the transfer sheet of this disclosure. The transfer sheet 1 shown in Figure 1 comprises a release substrate 10 and a transfer layer 20 that is peelably provided on the release substrate 10. The transfer layer 20 is provided with a surface protection layer 22 and a primer layer 24 in this order in the thickness direction from the side of the release substrate 10. That is, the release substrate 10, the surface protection layer 22 and the primer layer 24 are stacked in the thickness direction, which is the vertical direction on the plane of the paper in Figure 1.

[0017] The transfer layer 20 in the transfer sheet 1 shown in Figure 2 further comprises an adhesive layer 26. The transfer layer 20 is provided with a surface protection layer 22, a primer layer 24, and an adhesive layer 26 in this order in the thickness direction from the side of the release substrate 10. That is, the release substrate 10, the surface protection layer 22, the primer layer 24, and the adhesive layer 26 are stacked in the thickness direction, which is the vertical direction on the plane of the paper in Figure 2.

[0018] The configuration of the transfer sheet of this disclosure will be described in detail below.

[0019] The transfer sheet of this disclosure comprises a release substrate. As a release substrate, for example, a film composed of a resin component (hereinafter also referred to as "resin film") can be used. Examples of resin components include polyester, polyolefin, polystyrene, vinyl resin, (meth)acrylic resin, polyamide, polyimide, and polycarbonate. In this disclosure, "(meth)acrylic" encompasses both "acrylic" and "methacrylic," and "(meth)acrylate" encompasses both "acrylate" and "methacrylate."

[0020] Polyester films and polyolefin films are preferred as release substrates. Using these films as the release substrate allows for easy formation of, for example, a surface protective layer on the film.

[0021] Examples of polyesters include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), and polyethylene terephthalate-isophthalate copolymers. Among these, PET and PBT are preferred, with PET being more preferred, from the viewpoint of being less susceptible to thermal shrinkage during the manufacture of the transfer sheet and shrinkage due to irradiation with ionizing radiation.

[0022] Examples of polyolefins include polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, and ethylene-propylene-butene copolymer. Among these, polypropylene is preferred from the viewpoint of being less susceptible to thermal shrinkage during the manufacture of the transfer sheet and shrinkage due to irradiation with ionizing radiation.

[0023] The resin film may be a stretched film or an unstretched film, but a stretched film is preferred. The stretching ratio in the mechanical direction (MD) and / or width direction (TD) of the stretched film is, for example, 5 times or more and 30 times or less. By using a stretched resin film, it is possible to suppress thermal shrinkage of the resin film caused by heat treatment during the manufacture of the transfer sheet, and shrinkage of the resin film caused by crosslinking treatment by irradiation with ionizing radiation, thereby improving the dimensional stability of the transfer sheet.

[0024] The stretched film may be uniaxially oriented or biaxially oriented. A biaxially oriented film is preferred from the viewpoint of being less susceptible to thermal shrinkage during the manufacture of the transfer sheet and shrinkage due to irradiation with ionizing radiation.

[0025] The release substrate may have a single-layer structure or a multi-layer structure. The release substrate may be, for example, a single layer of resin film or a laminate of resin film. The laminate of resin film can be manufactured, for example, by dry lamination, wet lamination, or extrusion.

[0026] The surface of the release substrate to which the surface protective layer is provided may, if necessary, be subjected to known release treatments, or a release layer such as a silicone resin may be provided. This can improve, for example, the release properties between the surface protective layer and the release substrate during transfer.

[0027] The thickness of the release substrate is preferably 5 μm or more, more preferably 10 μm or more, preferably 200 μm or less, and more preferably 150 μm or less. If the release substrate has a multilayer structure, it is preferable that the entire multilayer structure is within the above thickness range.

[0028] In the transfer sheet of this disclosure, the transfer layer comprises a surface protective layer. The surface protection layer is a layer that constitutes the surface layer of a weather-resistant article obtained by transferring a transfer layer onto a transfer target via an adhesive layer as needed. The surface protection layer is, for example, a layer that imparts weather resistance to the transfer target, and may also be a layer that imparts scratch resistance and stain resistance. The surface protective layer is preferably in contact with the release substrate.

[0029] The surface protection layer is provided on the release substrate. In other words, the surface protection layer is superimposed on the release substrate in the thickness direction. In one embodiment, the surface protection layer is provided on the entire surface of the release substrate.

[0030] The surface protective layer contains a curing resin. The cured resin functions, for example, as a binder in the surface protective layer. Examples of cured resins include cured products of curable compounds. Examples of cured products of curable compounds include cured products of ionizing radiation-curable compounds and cured products of thermosetting resins. The surface protective layer may contain two or more of these cured resins.

[0031] Examples of thermosetting resins include unsaturated group-containing (meth)acrylic resins, unsaturated polyesters, urethane resins, epoxy resins, phenolic resins, aminoalkyd resins, urea resins, melamine resins, melamine-urea cocondensation resins, guanamine resins, diallyl phthalate resins, and silicone resins.

[0032] Along with the thermosetting resin, a curing agent is used as needed. In the case of unsaturated group-containing (meth)acrylic resins and unsaturated polyesters, for example, peroxides such as methyl ethyl ketone peroxide or radical initiators such as azoisobutylnitrile are used. In the case of urethane resins, for example, isocyanate-based curing agents are used. In the case of epoxy resins, for example, organic amine-based curing agents are used.

[0033] Examples of thermosetting resins include two-component curing urethane resins that use a polyol as the main component and an isocyanate compound as the curing agent. Examples of polyols include (meth)acrylic polyols, polyether polyols, polyester polyols, polyethylene glycols, and polypropylene glycols. The isocyanate compound is a polyvalent isocyanate having two or more isocyanate groups, and examples include aromatic isocyanates such as 4,4-diphenylmethane diisocyanate; and aliphatic (or alicyclic) isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate.

[0034] In one embodiment, the surface protective layer contains a cured product of a thermosetting resin as the curing resin, for example, a crosslinked cured product of (meth)acrylic polyol using an isocyanate-based curing agent.

[0035] Ionizing radiation-curable compounds are compounds that crosslink and harden upon irradiation with ionizing radiation, and possess ionizing radiation-curable functional groups. Ionizing radiation-curable functional groups are groups that crosslink upon irradiation with ionizing radiation, and examples include functional groups (ethylenically unsaturated groups) having ethylenic double bonds, such as (meth)acryloyl groups, vinyl groups, and allyl groups. Ionizing radiation refers to electromagnetic waves or charged particle beams that have energy quanta capable of polymerizing or crosslinking molecules. Examples of ionizing radiation include electron beams (EB) and ultraviolet rays (UV), as well as electromagnetic waves such as X-rays and gamma rays; and charged particle beams such as alpha rays and ion beams. From the viewpoint of including an ultraviolet absorber in the surface protective layer, electron beams are preferred as the ionizing radiation.

[0036] Examples of ionizing radiation-curable compounds include polymerizable monomers and polymerizable oligomers, which have been conventionally used as ionizing radiation-curable compounds. As polymerizable monomers, (meth)acrylate monomers having (meth)acryloyl groups in the molecule are preferred, and polyfunctional (meth)acrylate monomers having two or more (meth)acryloyl groups in the molecule are more preferred. The number of (meth)acryloyl groups in the polyfunctional (meth)acrylate monomer is two or more, preferably eight or less, and more preferably six or less.

[0037] Examples of polymerizable monomers include difunctional (meth)acrylates such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, bisphenol A tetraethoxy di(meth)acrylate and bisphenol A tetrapropoxy di(meth)acrylate; trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, Examples include trifunctional or more (meth)acrylates such as pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; and ethylene oxide modified, propylene oxide modified, caprolactone modified, isocyanuric acid modified, or propionic acid modified versions of these (meth)acrylates.

[0038] Examples of polymerizable oligomers include (meth)acrylate oligomers having two or more (meth)acryloyl groups in the molecule. Examples of (meth)acrylate oligomers include urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polycarbonate (meth)acrylate, polycaprolactone urethane (meth)acrylate, polycaprolactone diol urethane (meth)acrylate, and acrylic (meth)acrylate. The number of (meth)acryloyl groups in the polymerizable oligomer is two or more, preferably eight or less, and more preferably six or less.

[0039] Other polymerizable oligomers include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acryloyl groups in the side chains of polybutadiene oligomers, and silicone (meth)acrylate oligomers having polysiloxane bonds in the main chain.

[0040] The weight-average molecular weight of the polymerizable oligomer may be 500 or more, 1,000 or more, 2,000 or more, 10,000 or less, 8,000 or less, or 6,000 or less. The weight-average molecular weight is measured by gel permeation chromatography (GPC) analysis and is the average molecular weight converted to standard polystyrene.

[0041] As ionizing radiation-curable compounds, monofunctional (meth)acrylates may be used in combination with polyfunctional (meth)acrylates as appropriate, for purposes such as reducing the viscosity of the curable composition during coating. Examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate.

[0042] If the ionizing radiation-curable compound is an ultraviolet-curable compound, it is preferable to use at least one selected from a photopolymerization initiator and a photopolymerization accelerator together with the ultraviolet-curable compound.

[0043] The surface protective layer preferably contains a cured product of a curable compound, and more preferably a cured product of an ionizing radiation-curable compound, from the viewpoint of excellent heat resistance, scratch resistance, and stain resistance. Among ionizing radiation-curable compounds, electron beam-curable compounds are preferred as components for forming the surface protective layer because they can be made solvent-free, do not require a photopolymerization initiator, and provide stable curing properties. Among ionizing radiation-curable compounds, polymerizable oligomers are preferred, (meth)acrylate oligomers having two or more (meth)acryloyl groups in the molecule are more preferred, and urethane (meth)acrylates are even more preferred.

[0044] The content of cured resin relative to the total resin components contained in the surface protective layer is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0045] The surface protective layer contains a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength. Each absorption peak is based on the absorbance spectrum measured using an ultraviolet-visible-near-infrared spectrophotometer.

[0046] The first ultraviolet absorber has an absorption peak at a first wavelength. The first wavelength is preferably in the range of 270 nm to 300 nm, more preferably in the range of 270 nm to 290 nm, and even more preferably in the range of 270 nm to 280 nm.

[0047] The second ultraviolet absorber has an absorption peak at a second wavelength. The second wavelength is preferably in the range of 310 nm to 330 nm, and more preferably in the range of 310 nm to 325 nm.

[0048] The third ultraviolet absorber has an absorption peak at a third wavelength. The third wavelength is preferably in the range of 340 nm to 370 nm, and more preferably in the range of 345 nm to 365 nm.

[0049] The absorption peak mentioned above preferably refers to the maximum absorption peak in the wavelength range of 270 nm to 380 nm. For example, if the first ultraviolet absorber has multiple absorption peaks in the above wavelength range, it is preferable that the maximum absorption peak is in the range of 270 nm to 300 nm.

[0050] The difference between the second wavelength and the first wavelength is preferably 10 nm or more, more preferably 20 nm or more, even more preferably 30 nm or more, preferably 60 nm or less, more preferably 55 nm or less, and even more preferably 50 nm or less.

[0051] The difference between the third wavelength and the second wavelength is preferably 10 nm or more, more preferably 20 nm or more, even more preferably 30 nm or more, preferably 60 nm or less, more preferably 55 nm or less, and even more preferably 50 nm or less.

[0052] The difference between the third wavelength and the first wavelength is preferably 40 nm or more, more preferably 50 nm or more, even more preferably 60 nm or more, preferably 100 nm or less, more preferably 95 nm or less, and even more preferably 90 nm or less.

[0053] Examples of the first to third ultraviolet absorbers include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and benzophenone-based ultraviolet absorbers. Triazine-based ultraviolet absorbers are preferred from the viewpoint of excellent weather resistance, high absorbance, and wavelength selectivity.

[0054] Among triazine-based ultraviolet absorbers, hydroxyphenyltriazine-based ultraviolet absorbers are preferred from the viewpoint of weather resistance. Examples of hydroxyphenyltriazine-based ultraviolet absorbers include the compound represented by formula (1), the compound represented by formula (2), and the compound represented by formula (3).

[0055] [ka]

[0056] In formula (1), R 11 R is a divalent organic group, 12 -OC(=O)R 15 This is an acyloxy group represented by R 13 and R 14 Each of these is an independent monovalent organic group, R 15is a hydrogen atom or a monovalent organic group, and n 11 and n 12 are each independently an integer of 0 or more and 5 or less. When there are a plurality of R 13 s, each R 13 may be the same or different. When there are a plurality of R 14 s, each R 14 may be the same or different.

[0057] Examples of the divalent organic group of R 11 include aliphatic hydrocarbon groups such as an alkylene group and an alkenylene group. From the viewpoint of weather resistance, an alkylene group is preferable. From the viewpoint of weather resistance, the number of carbon atoms of the aliphatic hydrocarbon group is preferably 1 or more, more preferably 2 or more, preferably 16 or less, more preferably 12 or less, still more preferably 8 or less, and particularly preferably 4 or less. The aliphatic hydrocarbon group may be linear, branched or cyclic, and from the viewpoint of weather resistance, a linear or branched form is preferable, and a linear form is more preferable.

[0058] Examples of the monovalent organic groups of R 13 and R 14 include aliphatic hydrocarbon groups such as an alkyl group, an alkenyl group and a cycloalkyl group, and aromatic ring-containing hydrocarbon groups such as an aryl group and an arylalkyl group. From the viewpoint of weather resistance, an aromatic ring-containing hydrocarbon group is preferable, an aryl group is more preferable, and a phenyl group is particularly preferable.

[0059] From the viewpoint of weather resistance, n 11 and n 12 are each preferably 0.

[0060] R 15From the viewpoint of weather resistance, monovalent organic groups are preferred. Examples of monovalent organic groups include aliphatic hydrocarbon groups such as alkyl groups, alkenyl groups, and cycloalkyl groups, and aromatic ring-containing hydrocarbon groups such as aryl groups and arylalkyl groups. From the viewpoint of weather resistance, aliphatic hydrocarbon groups are preferred, and alkyl groups are more preferred. From the viewpoint of weather resistance, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 2 or more, more preferably 4 or more, preferably 16 or less, more preferably 12 or less, and even more preferably 10 or less. The aliphatic hydrocarbon group may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred.

[0061] [ka]

[0062] In formula (2), R 21 R is a hydrogen atom or a monovalent organic group, 22 and R 23 Each of these is independently a hydroxyl group or a monovalent organic group, n 21 , n 22 and n 23 Each of these is an independent integer between 1 and 5. 21 If there are multiple R 21 They may be the same or different. 22 If there are multiple R 22 They may be the same or different. 23 If there are multiple R 23 They may be the same or different.

[0063] R 21 As a monovalent organic group, R in formula (1) 13 and R 14 The groups exemplified as monovalent organic groups include, and in addition, -R 24 -C(=O)OR 25 The group represented by R is an example. 24 R is a divalent organic group, 25 R is a monovalent organic group. 22 and R 23As a monovalent organic group, R in formula (1) 13 and R 14 Examples of monovalent organic groups include those exemplified above. From the viewpoint of weather resistance, aromatic ring-containing hydrocarbon groups are preferred, aryl groups are more preferred, and phenyl groups are particularly preferred.

[0064] R 24 As for the divalent organic group, R in formula (1) 11 Examples of divalent organic groups include those exemplified above, and from the viewpoint of weather resistance, aliphatic hydrocarbon groups are preferred, and alkylene groups are more preferred. From the viewpoint of weather resistance, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 1 or more, more preferably 2 or more, preferably 16 or less, more preferably 12 or less, even more preferably 8 or less, and particularly preferably 4 or less. The aliphatic hydrocarbon group may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred, and linear is more preferred.

[0065] R 25 As a monovalent organic group, R in formula (1) 15 Examples of monovalent organic groups include those exemplified above, and from the viewpoint of weather resistance, aliphatic hydrocarbon groups are preferred, and alkyl groups are more preferred. From the viewpoint of weather resistance, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 2 or more, more preferably 4 or more, preferably 16 or less, more preferably 12 or less, and even more preferably 10 or less. The aliphatic hydrocarbon group may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred.

[0066] n 21 n can be 2 or more, 22 and n 23 Each of these can also be 1. In this case, multiple R 21 One of them may be a hydrogen atom, R 22 and R 23 If it is a monovalent organic group, it can be the same organic group.

[0067] [ka]

[0068] In formula (3), R 31 , R 32 and R 33 Each of these is independently a hydrogen atom or a monovalent organic group, n 31 , n 32 and n 33 Each of these is an independent integer between 1 and 5. 31 If there are multiple R 31 They may be the same or different. 32 If there are multiple R 31 They may be the same or different. 33 If there are multiple R 31 They may be the same or different.

[0069] R 31 , R 32 and R 33 As a monovalent organic group, R in formula (1) 13 and R 14 The groups exemplified as monovalent organic groups include, and in addition, -R 34 -C(=O)OR 35 The group represented by R is an example. 34 R is a divalent organic group, 35 It is a monovalent organic group.

[0070] R 34 As for the divalent organic group, R in formula (1) 11 Examples of divalent organic groups include those exemplified above, and from the viewpoint of weather resistance, aliphatic hydrocarbon groups are preferred, and alkylene groups are more preferred. From the viewpoint of weather resistance, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 1 or more, more preferably 2 or more, preferably 16 or less, more preferably 12 or less, even more preferably 8 or less, and particularly preferably 4 or less. The aliphatic hydrocarbon group may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred, and linear is more preferred.

[0071] R 35 As a monovalent organic group, R in formula (1) 15Examples of monovalent organic groups include those exemplified above, and from the viewpoint of weather resistance, aliphatic hydrocarbon groups are preferred, and alkyl groups are more preferred. From the viewpoint of weather resistance, the number of carbon atoms in the aliphatic hydrocarbon group is preferably 2 or more, more preferably 4 or more, preferably 16 or less, more preferably 12 or less, and even more preferably 10 or less. The aliphatic hydrocarbon group may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched is preferred.

[0072] n 31 , n 32 and n 33 Each of these can be 2 or more. In this case, multiple R 31 One of them may be a hydrogen atom, and multiple R 32 One of them may be a hydrogen atom, and multiple R 33 One of them could be a hydrogen atom.

[0073] Specifically, hydroxyphenyltriazine-based UV absorbers include 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine, 2-[ Examples include 4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol, 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, and compounds represented by the following formula.

[0074] [ka]

[0075] In the surface protective layer, the total content of the first ultraviolet absorber, the second ultraviolet absorber, and the third ultraviolet absorber per 100 parts by mass of cured resin is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, even more preferably 2 parts by mass or more, preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 6 parts by mass or less. When the total content of ultraviolet absorbers is above the lower limit, the weather resistance of the transfer layer tends to be improved. When the total content of ultraviolet absorbers is below the upper limit, the decrease in adhesion between the surface protective layer and the primer layer due to the bleeding out of the ultraviolet absorber tends to be suppressed.

[0076] In the surface protective layer, the content of the first ultraviolet absorber per 100 parts by mass of cured resin is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, even more preferably 0.3 parts by mass or more, preferably 3 parts by mass or less, more preferably 2 parts by mass or less, and even more preferably 1.5 parts by mass or less. This tends to improve, for example, weather resistance.

[0077] In the surface protective layer, the content of the second ultraviolet absorber per 100 parts by mass of cured resin is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1 part by mass or more, preferably 8 parts by mass or less, more preferably 6 parts by mass or less, and even more preferably 5 parts by mass or less. This tends to improve, for example, weather resistance.

[0078] In the surface protective layer, the content of the third ultraviolet absorber per 100 parts by mass of cured resin is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, even more preferably 0.3 parts by mass or more, preferably 3 parts by mass or less, more preferably 2 parts by mass or less, and even more preferably 1.5 parts by mass or less. This tends to improve, for example, weather resistance.

[0079] In one embodiment, the content of the second ultraviolet absorber in the surface protective layer is greater than the content of the first ultraviolet absorber and greater than the content of the third ultraviolet absorber. This allows the surface protective layer to absorb a wide range of wavelengths, which tends to improve weather resistance, for example.

[0080] The surface protective layer may contain a light stabilizer from the viewpoint of weather resistance. Examples of light stabilizers include aromatic light stabilizers, amine light stabilizers, organic acid light stabilizers, catechin light stabilizers, and hindered amine light stabilizers, with hindered amine light stabilizers being preferred among these. Hindered amine light stabilizers are, for example, compounds having a structure that includes a 2,2,6,6-tetramethylpiperidine skeleton within the molecule.

[0081] Examples of light stabilizers include reactive light stabilizers having an ethylenically bond polymerizable with a curable compound that can form a curable resin of the surface protective layer, and non-reactive light stabilizers that do not have an ethylenically bond polymerizable with the curable compound. Ethylenelycols are found in functional groups such as (meth)acryloyl groups, vinyl groups, and allyl groups. The surface protective layer may contain at least one selected from the reactive light stabilizer and the non-reactive light stabilizer, or it may contain both the reactive and non-reactive light stabilizer.

[0082] Reactive light stabilizers are typically incorporated into the curing resin system during the formation of the surface protective layer and are immobilized, thus providing long-term effects. Non-reactive light stabilizers can move within the surface protective layer and therefore provide immediate effects.

[0083] The number of ethylenic double bonds in the reactive light stabilizer may be one or two or more.

[0084] Examples of reactive light stabilizers having one ethylenically 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 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 with CAS number 1010692-24-6, and the compound with CAS number 1010692-21-3. Examples of reactive light stabilizers having two or more ethylenically active 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 with CAS number 1954659-42-7, and the compound with CAS number 1010692-23-5.

[0085] Examples of non-reactive light stabilizers 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. Examples include 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, and bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate.

[0086] In the surface protective layer, the content of the light stabilizer per 100 parts by mass of the cured resin is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, even more preferably 1.5 parts by mass or more, preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 6 parts by mass or less.

[0087] The surface protective layer may contain only the reactive light stabilizer, only the non-reactive light stabilizer, or both the reactive and non-reactive light stabilizers as light stabilizers. The mass-based mixing ratio (reactive light stabilizer:non-reactive light stabilizer) of the reactive and non-reactive light stabilizers in the surface protective layer may be, for example, 10:0 to 2:8.

[0088] The surface protective layer may contain additives, such as antioxidants, wear resistance enhancers, infrared absorbers, antistatic agents, leveling agents, thixotropic agents, coupling agents, defoaming agents, flame retardants, plasticizers, particles, and antiblocking agents.

[0089] The surface protective layer preferably contains substantially no polyolefins. This tends to improve the weather resistance of the surface protective layer, for example. Concretely containing no polyolefins means that the polyolefin content relative to the total resin components in the surface protective layer is 1% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass.

[0090] In the transfer sheet of this disclosure, it is preferable that the surface protective layer has an absorbance A1 of 0.3 or more at a wavelength of 270 nm to 300 nm, an absorbance A2 of 0.6 or more at a wavelength of 310 nm to 330 nm, and an absorbance A3 of 0.2 or more at a wavelength of 340 nm to 370 nm.

[0091] As mentioned above, from the perspective of long-term weather resistance, by considering absorbance A2 at wavelengths of 310 nm to 330 nm and absorbance A3 at wavelengths of 340 nm to 370 nm, in addition to absorbance A1 at wavelengths of 270 nm to 300 nm, the surface protective layer can efficiently cut ultraviolet rays, further improving the weather resistance of the transfer layer in environments exposed to direct sunlight.

[0092] The absorbance A1 is preferably 0.3 or higher, more preferably 0.35 or higher, and may also be 0.5 or higher, or 0.7 or higher. The upper limit of the absorbance A1 is not particularly limited, but may be 1.5, for example.

[0093] The absorbance A2 is preferably 0.6 or higher, more preferably 0.7 or higher, and may be, for example, 1.0 or higher, or 1.2 or higher. The upper limit of the absorbance A2 is not particularly limited, but may be, for example, 3.0.

[0094] The absorbance A3 is preferably 0.2 or higher, more preferably 0.25 or higher, and may also be, for example, 0.5 or higher, or 0.7 or higher. The upper limit of the absorbance A3 is not particularly limited, but may be, for example, 1.5.

[0095] Absorbances A1, A2, and A3 can be adjusted, for example, by the content of the first to third UV absorbers in the surface protective layer and the thickness of the surface protective layer. For example, the absorbance can be easily adjusted by having the surface protective layer contain the first to third UV absorbers, respectively.

[0096] In one embodiment, the absorbance of the surface protective layer in the wavelength range of 270 nm to 370 nm includes a maximum value in the range of 300 nm to 340 nm. This tends to improve, for example, the long-term weather resistance of the transfer layer.

[0097] Each absorbance is measured as follows: Absorbance A1 shall be the average value of the absorbance of the surface protective layer at wavelengths between 270 nm and 300 nm, in accordance with JIS K0115:2004. This average value shall be the average of absorbance measurements taken at 1 nm intervals between 270 nm and 300 nm. In accordance with JIS K0115:2004, the average absorbance of the surface protective layer at wavelengths between 310 nm and 330 nm shall be defined as absorbance A2. This average value is the average of absorbance measurements taken at 1 nm intervals between 310 nm and 330 nm. In accordance with JIS K0115:2004, the average absorbance of the surface protective layer at wavelengths between 340 nm and 370 nm shall be defined as absorbance A3. This average value is the average of absorbance measurements taken at 1 nm intervals between 340 nm and 370 nm.

[0098] The absorbance of the surface protective layer of a transfer sheet can be measured as follows: Remove the layers outside the surface protective layer of the transfer sheet (e.g., the primer layer and adhesive layer) by cutting or using a solvent, and measure the absorbance of the remaining laminate. Then, measure the absorbance of the release substrate alone. The absorbance of the surface protective layer can be obtained by subtracting the absorbance of the release substrate alone from the absorbance of the remaining laminate.

[0099] In one embodiment, the surface protective layer can be formed by preparing a curable composition, applying the composition to a release-type substrate to form an uncured resin layer, and then crosslinking and curing the uncured resin layer. The manner of crosslinking and curing varies; for example, when using a thermosetting resin, it is cured by heat treatment, and when using an ionizing radiation-curable compound, it is cured by irradiation with ionizing radiation such as electron beams and ultraviolet rays.

[0100] When electron beams are used as ionizing radiation, the irradiation dose is, for example, 5 kGy to 300 kGy (0.5 Mrad to 30 Mrad), preferably 10 kGy to 100 kGy (1 Mrad to 10 Mrad). When ultraviolet light is used as ionizing radiation, light including ultraviolet light with a wavelength of 190 nm to 380 nm may be emitted.

[0101] The thickness of the surface protective layer is preferably 1 μm or more, more preferably 1.5 μm or more, even more preferably 2 μm or more, preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less, from the viewpoint of balancing processability, scratch resistance, and weather resistance.

[0102] In the transfer sheet of this disclosure, the transfer layer comprises a primer layer. The primer layer may be provided, for example, to improve the adhesion between the surface protective layer and the adhesive layer.

[0103] In one embodiment, the primer layer contains a resin component. Examples of resin components include vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-(meth)acrylic copolymer, chlorinated polyethylene, chlorinated polypropylene, urethane resin, (meth)acrylic resin, (meth)acrylic polyol resin, polystyrene, polyester, polyamide, butyral resin, nitrocellulose, and cellulose acetate. The resin component may also be a cross-linked cured product of these resins using a curing agent. The resin component may also be, for example, a cured product of the two-component curable urethane resin described above.

[0104] As for the urethane resin, a urethane resin having a (meth)acrylic skeleton in the polyurethane polymer chain is preferred from the viewpoint of weather resistance and durability. Examples of urethane resins having a (meth)acrylic skeleton in the polyurethane polymer chain include urethane-(meth)acrylic copolymers, which are copolymers of a urethane component and a (meth)acrylic component, and resins in which a (meth)acrylic resin having a hydroxyl group or isocyanate group as the polyol component or polyisocyanate component constituting the polyurethane is used. Among these, urethane-(meth)acrylic copolymers are preferred, and as urethane-(meth)acrylic copolymers, for example, urethane-(meth)acrylic block copolymers are preferred.

[0105] From the viewpoint of adhesion between the primer layer and the surface protective layer, the urethane-(meth)acrylic copolymer may further have a polycarbonate backbone or a polyester backbone in the polyurethane polymer chain. Examples of such urethane-(meth)acrylic copolymers include polycarbonate-based urethane-(meth)acrylic copolymers, which are copolymers of a polycarbonate-based urethane component and a (meth)acrylic component, and polyester-based urethane-(meth)acrylic copolymers, which are copolymers of a polyester-based urethane component and a (meth)acrylic component.

[0106] Urethane-(meth)acrylic copolymers can be obtained, for example, by reacting a polyol and a polyisocyanate with a (meth)acrylic resin having at least two hydroxyl groups in one molecule (see Japanese Patent Publication No. 6-100653, etc.) or by reacting a (meth)acrylic monomer with a urethane prepolymer having unsaturated double bonds at both ends (see Japanese Patent Publication No. 10-1524, etc.).

[0107] Examples of urethane prepolymers include polycarbonate-based urethane prepolymers obtained by reacting a polycarbonate diol with a diisocyanate, and polyester-based urethane prepolymers obtained by reacting a polyester diol with a diisocyanate. Examples of diisocyanates include aliphatic isocyanates such as hexamethylene diisocyanate, and alicyclic isocyanates such as isophorone diisocyanate and hydrogenated xylylene diisocyanate. Examples of (meth)acrylic monomers include (meth)acrylic acid and alkyl (meth)acrylate esters with an alkyl group having 1 to 6 carbon atoms.

[0108] Examples of urethane resins include polycarbonate-based urethane-(meth)acrylic copolymers, polyester-based urethane-(meth)acrylic copolymers, polyether-based urethane-(meth)acrylic copolymers, and caprolactone-based urethane-(meth)acrylic copolymers. These resin components are preferred from the viewpoint of improving weather resistance and the adhesion between the surface protective layer and the adhesive layer.

[0109] In urethane resins, the urethane component / (meth)acrylic component (mass ratio) is preferably 20 / 80 to 99 / 1, more preferably 50 / 50 to 95 / 5, and even more preferably 70 / 30 to 95 / 5. This can, for example, further improve weather resistance. The (meth)acrylic component content in a urethane resin is the ratio of monomer units constituting the (meth)acrylic skeleton to the total mass of the urethane resin. The (meth)acrylic component content in a urethane resin is calculated by measuring the NMR spectrum of the urethane resin and determining the ratio of the peak area attributed to the (meth)acrylic component to the total peak area.

[0110] The weight-average molecular weight of the urethane resin may be 10,000 or more, 30,000 or more, 100,000 or less, or 80,000 or less. This can, for example, further improve weather resistance. The weight-average molecular weight used herein is determined by gel permeation chromatography (GPC) as a standard polystyrene equivalent.

[0111] The resin component content in the primer layer is, for example, 50% by mass or more.

[0112] The primer layer may contain UV absorbers such as the first to third UV absorbers described above. The primer layer may contain the light stabilizers described above. The primer layer may contain the additives described above.

[0113] If the primer layer contains an ultraviolet absorber, the amount of ultraviolet absorber in the primer layer may be 1 part by mass or more, 5 parts by mass or more, 10 parts by mass or more, 50 parts by mass or less, 45 parts by mass or less, or 40 parts by mass or less, based on 100 parts by mass of the resin component contained in the primer layer.

[0114] If the primer layer contains a light stabilizer, the amount of light stabilizer in the primer layer may be 0.1 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, 10 parts by mass or less, 8 parts by mass or less, or 6 parts by mass or less, based on 100 parts by mass of the resin component contained in the primer layer.

[0115] The thickness of the primer layer is preferably 0.1 μm or more, more preferably 0.5 μm or more, even more preferably 1 μm or more, preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 6 μm or less.

[0116] To improve adhesion between the surface protective layer and the primer layer, the surface protective layer may be surface-treated before the primer layer is formed. Examples of surface treatment methods include corona discharge treatment, plasma treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment.

[0117] To improve the adhesion between the surface protection layer and the primer layer, the cross-linking and curing of the surface protection layer may be left in a semi-cured state. After that, the resin composition for the primer layer may be applied to the semi-cured surface protection layer, and then the surface protection layer may be fully cured by irradiation with ionizing radiation.

[0118] When a primer layer is formed by applying a resin composition for the primer layer onto the surface protective layer after the surface protective layer has been cured, it can be difficult to achieve sufficiently high adhesion between the primer layer and the surface protective layer. In such cases, for example, if the primer layer deteriorates due to ultraviolet irradiation in an environment exposed to direct sunlight, delamination between the primer layer and the surface protective layer is likely to occur. In this disclosure, since the deterioration of the primer layer can be suppressed over the long term as described above, such delamination can be suppressed.

[0119] In the transfer sheet of this disclosure, the transfer layer may include a design layer. The transfer layer may include a design layer between the primer layer and the adhesive layer. The design layer may be located on a portion of the surface of the primer layer opposite to the surface protection layer, or it may be located on the entire surface. The design layer may also be a layer that covers the entire surface of the primer layer opposite to the surface protection layer, or it may be a pattern that includes areas where the design is located and areas where it is not located on the surface of the primer layer opposite to the surface protection layer.

[0120] A design layer may be provided to display a design. The design layer may, for example, have a pattern. Examples of patterns include wood grain patterns that mimic the annual rings or vessel grooves on the surface of a wooden board, stone patterns that mimic the surface of rocks such as marble and granite, fabric patterns that mimic the texture or fabric-like pattern of cloth, leather grain patterns that mimic the surface of leather, pear-skin patterns, tile patterns, brick patterns, geometric patterns, and abstract patterns such as letters, figures, symbols, polka dots, and floral patterns. The pattern may be a solid color (a so-called solid image). The pattern may also be a composite pattern that includes two or more of these types. The design layer may have two or more layers. For example, the design layer may have a colored first layer and a second layer provided on the first layer to form a pattern.

[0121] The design layer can be formed, for example, by printing or coating methods. Printing methods include, for example, gravure printing, offset printing, screen printing, transfer printing from a transfer sheet, and inkjet printing. Coating methods include, for example, gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, and reverse roll coating. Other layers can also be formed, for example, by these methods.

[0122] In one embodiment, the design layer contains a resin component and a coloring agent. Examples of resin components include vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-(meth)acrylic copolymer, chlorinated polyethylene, chlorinated polypropylene, urethane-(meth)acrylic copolymer, (meth)acrylic resin, (meth)acrylic polyol resin, polystyrene, polyurethane, polyester, polyamide, butyral resin, nitrocellulose, and cellulose acetate.

[0123] Examples of colorants include pigments and dyes. Specifically, these include inorganic pigments such as carbon black, iron black, titanium white, antimony white, lead yellow, titanium yellow, iron oxide, cadmium red, ultramarine, and cobalt blue; organic pigments or dyes such as quinacridone red, isoindolinone yellow, phthalocyanine blue, azomethine azoblack, and nickel azo complexes; metallic pigments consisting of flaky foil pieces such as aluminum and brass; and pearlescent pigments consisting of flaky foil pieces such as titanium dioxide-coated mica and basic lead carbonate.

[0124] The amount of colorant in the design layer may be 5 parts by mass or more, 15 parts by mass or more, 30 parts by mass or more, 200 parts by mass or less, 150 parts by mass or less, or 100 parts by mass or less, based on 100 parts by mass of the resin component contained in the design layer.

[0125] The design layer may contain additives. Examples of additives include ultraviolet absorbers, light stabilizers, antioxidants, fillers, defoamers, flame retardants, plasticizers, and lubricants. From the viewpoint of improving weather resistance, the design layer may also contain weathering agents such as ultraviolet absorbers, light stabilizers, and antioxidants.

[0126] The thickness of the design layer is preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 2 μm or more, preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less. This can improve the aesthetic appeal, for example.

[0127] The design layer may have a thin metal film. Examples of metals that make up the thin metal film include tin, indium, chromium, aluminum, nickel, iron, cobalt, copper, silver, gold, platinum, and zinc, as well as alloys containing at least one of these metals. Examples of alloys include brass, bronze, and stainless steel. Examples of methods for forming the thin metal film include vacuum deposition, sputtering, and ion plating. The thickness of the thin metal film is, for example, 0.1 μm to 1 μm. The adhesive layer may also serve as the design layer.

[0128] In the transfer sheet of this disclosure, the transfer layer may include an adhesive layer. The adhesive layer has the function of adhering the transfer sheet to the surface of the object to be transferred. In one embodiment, the adhesive layer constitutes the surface layer of the transfer layer opposite to the release substrate side. The adhesive layer is the layer that comes into contact with the object to be transferred after transfer. This allows the transfer layer to be transferred and attached to the object to be transferred smoothly.

[0129] In this disclosure, a transfer sheet is attached to a transfer object so that the adhesive layer is in contact with the surface of the transfer object, and then the release substrate is peeled off, thereby allowing a transfer layer comprising a surface protective layer and a primer layer to be transferred from the transfer sheet onto the transfer object with good adhesion.

[0130] Suitable adhesive resins for the adhesive layer include, for example, heat-sealable resins such as (meth)acrylic resin, polyolefin, chlorinated polyolefin, vinyl chloride-vinyl acetate copolymer, polyamide, polyester, chlorinated rubber, urethane resin, epoxy resin, and styrene resin. Among these, (meth)acrylic resins such as polymethyl methacrylate resin are preferred from the viewpoint of improving weather resistance.

[0131] The content of the adhesive resin in the adhesive layer is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more.

[0132] The adhesive layer may contain additives. Examples of additives include weathering agents such as ultraviolet absorbers and light stabilizers, abrasion resistance enhancers, infrared absorbers, antistatic agents, adhesion enhancers, leveling agents, thixotropic agents, coupling agents, plasticizers, defoamers, fillers, and colorants.

[0133] The adhesive layer may contain a weather-resistant agent. Details of the weather-resistant agent are as described above. The amount of ultraviolet absorber in the adhesive layer may be 0.1 parts by mass or more, 1 part by mass or more, 3 parts by mass or more, 25 parts by mass or less, 20 parts by mass or less, or 15 parts by mass or less, per 100 parts by mass of adhesive resin. The amount of light stabilizer in the adhesive layer may be 0.05 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, 7 parts by mass or less, or 5 parts by mass or less, per 100 parts by mass of adhesive resin.

[0134] The thickness of the adhesive layer is preferably 1 μm or more, preferably 12 μm or less, and more preferably 6 μm or less. This allows, for example, the transfer layer to adhere well to the object to be transferred, and also ensures excellent transparency.

[0135] The thickness of the adhesive layer is preferably greater than the thickness of the primer layer.

[0136] The adhesive layer can be formed, for example, by applying a composition containing the components that make up the adhesive layer (adhesive layer composition) onto a primer layer and drying it as needed.

[0137] The transfer sheet of this disclosure may include a cover film (protective film) on the adhesive layer. Specifically, a cover film may be attached to the adhesive layer. This provides good protection for the surface of the adhesive layer, which is preferable for storing the transfer sheet. When using the transfer sheet, the cover film is peeled off from the adhesive layer to expose the adhesive layer, and the transfer sheet is attached to the object to be transferred via this adhesive layer.

[0138] The cover film is made of a resin component such as polyolefin.

[0139] The weather-resistant article of this disclosure comprises a transfer sheet and a surface protective film provided on at least a portion of the surface of the transfer sheet. The surface protective film is a transfer layer in the transfer sheet of this disclosure, and the surface protective layer included in the transfer layer constitutes the surface layer of at least a portion of the weather-resistant article.

[0140] In one embodiment, as shown in Figure 3, the weather-resistant article 2 comprises a transfer body 30 and a transfer layer 20 provided on the surface of the transfer body 30. In the embodiment shown in Figure 3, the transfer layer 20 comprises an adhesive layer 26, a primer layer 24, and a surface protection layer 22, in this order from the side of the transfer body 30. Therefore, the weather-resistant article 2 has the adhesive layer 26, primer layer 24, and surface protection layer 22 on the transfer body 30 in this order. The release substrate 10 only needs to be peeled off when the weather-resistant article 2 is used.

[0141] The object to be transferred is an article onto which the transfer layer of the transfer sheet of this disclosure is transferred. Examples of materials to be transferred include exterior materials. Exterior materials to which the transfer layer of the transfer sheet of this disclosure has been transferred can maintain good weather resistance even after being exposed to harsh outdoor conditions.

[0142] Exterior materials are molded articles used outdoors, such as those used in applications where weather resistance is required due to daily exposure to direct sunlight. The transfer layer in the transfer sheet of this disclosure is suitable for exterior material applications because it has excellent weather resistance. The shape of the exterior material is not particularly limited and examples include flat plates and curved plates, three-dimensional articles, sheets, or films. Examples of exterior materials include resin components, wood components, and inorganic components.

[0143] Examples of resin components include sheets, plates, or three-dimensional articles made from polyolefins, vinyl chloride resins, styrene resins, (meth)acrylic resins, polyesters, polycarbonates, polyamides, polyimides, cellulose resins, phenolic resins, rubber, and the like.

[0144] Examples of wood-based materials include boards or three-dimensional articles made from wood fiberboards such as wood veneer, wood plywood, particleboard, medium-density fiberboard (MDF), and laminated wood.

[0145] Examples of inorganic materials include metal materials and other inorganic materials. Examples of metal materials include sheets, plates, or three-dimensional articles made from iron, aluminum, copper, tin, titanium, or alloys containing at least one of these metals (e.g., carbon steel, stainless steel, duralumin, brass, and bronze). Examples of other inorganic materials include plates or three-dimensional articles made from glass, ceramics such as porcelain, non-cement ceramic materials such as gypsum, or autoclaved lightweight concrete (ALC) panels.

[0146] Examples of exterior materials include exterior materials for building structures, exterior materials for vehicles, ships and aircraft, exterior materials for industrial machinery, and various types of lenses. Examples of exterior materials for building structures (building materials) include exterior walls, roofs, eaves, floors, fences, various doors such as entrance doors and gates, window materials, railings, balcony partitions, roofing components for terraces or carports, agricultural greenhouses, soundproof walls or windbreaks on general roads and highways, etc. Examples of exterior materials for vehicles include window materials such as side windows, rear windows, roof windows, front windows and quarter windows; headlight covers, turn signal lamp lenses, reflectors; and pillars. Examples of vehicles include automobiles, railway cars, construction machinery, and light vehicles such as golf carts. Examples of exterior materials for industrial machinery include visibility window materials for machine tools. Examples of lenses include traffic light lenses.

[0147] The thickness of the exterior material can be appropriately selected depending on the application and material. In one embodiment, it may be 0.1 mm or more, 0.3 mm or more, 0.5 mm or more, 10 mm or less, 5 mm or less, or 3 mm or less.

[0148] The above-mentioned transfer targets are not limited to exterior materials, but can also include, for example, interior materials for vehicles, ships and aircraft, interior materials for building structures, front panels for various display devices, convex mirrors, traffic signs, and nameplates. The object to be transferred may be, for example, a decorative material such as a decorative panel.

[0149] The weather-resistant articles of the present disclosure can be obtained, for example, by using the transfer sheet of the present disclosure and transferring the transfer layer of the transfer sheet onto at least a portion of the surface of an object to be transferred. In one embodiment, a method for manufacturing the weather-resistant articles of the present disclosure includes the steps of preparing the transfer sheet and the object to be transferred, placing the transfer sheet on the object to be transferred such that the transfer layer of the transfer sheet faces the object to be transferred, and peeling off the release material from the transfer sheet.

[0150] In one embodiment, a transfer sheet of the present disclosure comprising a transfer layer including a surface protective layer, a primer layer, and an adhesive layer, and a transfer object are prepared, and the transfer sheet is placed on at least a portion of the surface of the transfer object such that the adhesive layer on the transfer sheet is in contact with the surface of the transfer object.

[0151] In one embodiment, a transfer sheet of the present disclosure comprising a transfer layer including a surface protective layer and a primer layer, and a transfer object having an adhesive layer on its surface are prepared, and the transfer sheet is placed on at least a portion of the surface of the transfer object so that the transfer layer on the transfer sheet and the adhesive layer provided on the transfer object are in contact. Examples of the adhesive layer provided on the transfer object include the adhesive layer that can be provided on the transfer layer of the transfer sheet.

[0152] The above arrangement may be carried out under heating and / or pressure. Next, the release material on the transfer sheet is peeled off from the transfer layer, specifically from the surface protective layer. In this way, a weather-resistant article is obtained. As for the transfer method, for example, a heat transfer method such as the roll transfer method and the press transfer method, or an in-mold molding method can be used.

[0153] The release agent may be used as a protective film for weather-resistant articles without immediately peeling it off the transfer layer. In such cases, the release agent should be peeled off the transfer layer before using the weather-resistant article.

[0154] After placing the transfer sheet on the surface of the object to be transferred, the resulting weather-resistant article may be subjected to further processing such as bending. The processing may be carried out either before or after peeling off the release substrate.

[0155] The weather-resistant articles of this disclosure may be manufactured, for example, by simultaneously forming the object to be transferred and arranging the transfer sheet. For example, resin is injected onto the adhesive layer of the transfer sheet to integrate the transfer sheet with the resin molded body (injection molded body) as the object to be transferred. Then, the release substrate is peeled off from the transfer layer. In this case, examples of methods for forming the resin molded body include various injection molding methods such as in-mold molding, insert molding, injection molding with simultaneous decoration, blow molding, and gas injection molding.

[0156] This disclosure relates, for example, to the following [1] to

[15] . [1] A transfer sheet comprising a release substrate and a transfer layer, wherein the transfer layer comprises a surface protection layer and a primer layer, the surface protection layer is located between the release substrate and the primer layer, and the surface protection layer contains a curing resin, a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength. [2] The transfer sheet as described in [1] above, wherein the difference between the second wavelength and the first wavelength is 10 nm or more, and the difference between the third wavelength and the second wavelength is 10 nm or more. [3] The transfer sheet described in [1] or [2] above, wherein the second wavelength is in the range of 310 nm to 330 nm. [4] A transfer sheet according to any of [1] to [3] above, wherein the first wavelength is in the range of 270 nm to 300 nm. [5] A transfer sheet according to any of [1] to [4] above, wherein the third wavelength is in the range of 340 nm to 370 nm. [6] A transfer sheet according to any of [1] to [5] above, wherein the content of the second ultraviolet absorber in the surface protective layer is greater than the content of the first ultraviolet absorber and greater than the content of the third ultraviolet absorber. [7] A transfer sheet according to any of [1] to [6] above, wherein the first ultraviolet absorber, the second ultraviolet absorber, and the third ultraviolet absorber are each independently triazine-based ultraviolet absorbers. [8] A transfer sheet according to any one of [1] to [7] above, wherein the surface protective layer contains a total of 0.5 parts by mass or more and 10 parts by mass or less of the first ultraviolet absorber, the second ultraviolet absorber, and the third ultraviolet absorber, per 100 parts by mass of the cured resin contained in the surface protective layer. [9] A transfer sheet according to any one of [1] to [8] above, wherein the surface protective layer contains, per 100 parts by mass of the cured resin contained in the surface protective layer, 0.1 parts by mass to 3 parts by mass of a first ultraviolet absorber, 0.1 parts by mass to 8 parts by mass of a second ultraviolet absorber, and 0.1 parts by mass to 3 parts by mass of a third ultraviolet absorber.

[10] A transfer sheet according to any one of [1] to [9] above, wherein the primer layer contains an ultraviolet absorber.

[11] A transfer sheet according to any of [1] to

[10] above, wherein the transfer layer further comprises a design layer.

[12] The transfer sheet according to any one of [1] to

[11] above, wherein the transfer layer further comprises an adhesive layer as a surface layer on the side opposite to the release substrate side.

[13] A transfer sheet according to any one of [1] to

[12] above for transferring a transfer layer onto at least a portion of the surface of an exterior material.

[14] A weather-resistant article comprising a transfer body and a surface protective film provided on at least a portion of the surface of the transfer body, wherein the surface protective film is the transfer layer in the transfer sheet described in any of [1] to

[13] above, and the surface protective layer in the transfer layer constitutes the surface layer of at least a portion of the weather-resistant article.

[15] The weather-resistant article according to

[14] above, wherein the transfer layer comprises an adhesive layer, or an adhesive layer is provided between the transfer layer and the object to be transferred. [Examples]

[0157] The transfer sheet of this disclosure will be described in more detail below based on examples, but the transfer sheet of this disclosure is not limited in any way by the examples.

[0158] [Example 1] An untreated matte PET film (PET raw material Diafoil E130-26, Mitsubishi Chemical) was prepared as a release substrate. Approximately 5 g of the following ionizing radiation-curable resin composition was applied to the release substrate to form an uncured resin layer. The uncured resin layer was cured by irradiation with an electron beam (acceleration voltage: 175 kV, irradiation dose: 5 Mrad (50 kGy)) to form a 5 μm thick surface protective layer. Corona discharge treatment was performed on the surface protective layer. Approximately 2.5 g of the following primer layer resin composition was applied to the surface protective layer after corona discharge treatment by gravure printing and dried to form a 3.5 μm thick primer layer. Approximately 5 g of heat-sealable resin (polymethyl methacrylate resin (PMMA), molecular weight approximately 96000) was applied to the primer layer to form a 4.5 μm thick adhesive layer (heat seal layer), and cured at room temperature for 24 hours.

[0159] A transfer sheet was obtained as described above. The transfer sheet comprises a PET film as a release substrate and a transfer layer provided on the PET film, the transfer layer comprising a surface protection layer, a primer layer and an adhesive layer.

[0160] <Ionizing radiation curable resin composition> • 100 parts by mass of a trifunctional urethane acrylate oligomer with a weight-average molecular weight of 4,000 • 0.5 parts by mass of the first ultraviolet absorber Hydroxyphenyltriazine-based UV absorbers, Product name: ADEKA stub LA-46, ADEKA Corporation Wavelength of absorption peak: 275nm • Second UV absorber: 3 parts by mass Hydroxyphenyltriazine-based UV absorbers, Product name: TINUVIN479, BASF Wavelength of absorption peak: 322nm • Third UV absorber: 0.5 parts by mass Hydroxyphenyltriazine-based UV absorbers, Product name: TINUVIN477, BASF Wavelength of absorption peak: 356nm • Hindered amine-based reactive light stabilizer: 3 parts by mass Product name: Sanol LS-3410, Nippon Emulsifier Co., Ltd. 1,2,2,6,6-Pentamethyl-4-piperidinyl-methacrylate

[0161] <Resin composition for primer layer> • Polycarbonate-based urethane-acrylic copolymer 100 parts by mass (Urethane component / Acrylic component = 70 / 30 (by mass)) • Hydroxyphenyltriazine-based UV absorber: 30 parts by mass (Product name: Tinuvin479 (2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, BASF) 15 parts by mass, Product Name: Tinuvin400 (2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, BASF) 15 parts by mass) • Hindered amine-based light stabilizer: 3.5 parts by mass (Product name: Tinuvin123 (BASF), Bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate)

[0162] [Comparative Example 1] A transfer sheet was obtained in the same manner as in Example 1, except that the first ultraviolet absorber in the ionizing radiation-curable resin composition was omitted, the amount of the second ultraviolet absorber (TINUVIN479) was changed to 1 part by mass, the amount of the third ultraviolet absorber (TINUVIN477) was changed to 3 parts by mass, and the hindered amine-based reactive light stabilizer was omitted.

[0163] [Absorbance] A surface protective layer was formed on a PET film under the same conditions as described above to prepare test specimens. Using a UV-Vis-Near-Infrared spectrophotometer (Hitachi, Ltd., product name: UH-4150), the absorbance of the test specimens in each wavelength range was measured in accordance with JIS K0115:2004. By subtracting the absorbance of the PET film from these absorbances, the above-mentioned "Absorbance A1," "Absorbance A2," and "Absorbance A3" were obtained.

[0164] The absorbances of the surface protective layers corresponding to the transfer sheet of Example 1 were as follows: Absorbance A1:1.2 Absorbance A2:1.6 Absorbance A3:1.4

[0165] The absorbances of the surface protective layers corresponding to the transfer sheet of Comparative Example 1 were as follows: Absorbance A1:0.25 Absorbance A2:0.6 Absorbance A3:1.2

[0166] [Transcription] Transfer sheets obtained in the examples and comparative examples, and a 2 mm thick polycarbonate sheet were prepared as the transfer target. No weather-resistant agent was added to the polycarbonate sheet. The transfer sheet was placed on one side of a polycarbonate sheet heated to 130°C, with the adhesive layer of the transfer sheet in contact with the polycarbonate sheet, and pressed using a roll at 160°C. This obtained a molded body with a release substrate, comprising a polycarbonate sheet, adhesive layer, primer layer, surface protection layer, and release substrate in that order. Next, the release substrate was peeled off the transfer layer of the transfer sheet to obtain a test specimen. The surface protection layer constitutes the surface layer on one side of the test specimen.

[0167] [Weather resistance] Using the accelerated weathering test apparatus described below, the above test specimens were subjected to an accelerated weathering test (a test in which one cycle consists of irradiating with ultraviolet light for 20 hours under the irradiation conditions described below, followed by condensation for 4 hours under the condensation conditions described below, and repeating this cycle) for 800 hours.

[0168] <Ultra-accelerated weathering test equipment> An accelerated weathering test apparatus (product name: "i Super UV Tester SUV-W261", manufactured by Iwasaki Electric Co., Ltd.) is equipped with 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 illuminance meter (product name: UVD-365PD, manufactured by Iwasaki Electric Co., Ltd.). <Irradiation conditions> • Black panel temperature: 63℃ ·Illuminance: 100mW / cm 2 ·Battle humidity: 50%RH • Time: 20 hours <Condensation conditions> ·Illuminance: 0mW / cm 2 ·Battle humidity: 98%RH • Duration: 4 hours

[0169] [Adhesion evaluation] After conducting the above weather resistance test for 800 hours, a cellophane tape resistance test was performed on the test specimens, and the presence or absence of peeling of the surface protective layer was visually observed and evaluated as follows. The cellophane tape resistance test was performed by applying a cellophane adhesive tape manufactured by Nichiban Co., Ltd., with a test area of ​​1.5 cm x 1.5 cm to the surface of the surface protective layer side of the test specimen, and pulling it forcefully towards the user at a 45-degree angle. ○: No peeling of the surface protective layer. △: Peeling of the surface protective layer occurred in less than 50% of the test area. ×: Peeling of the surface protective layer occurred in more than 50% of the test area. The results were as follows: • Example 1: ○ • Comparative Example 1: △ [Explanation of symbols]

[0170] 1…Transfer sheet 2...Weather resistant articles 10…Releasable base material 20…Transfer layer 22…Surface protective layer 24…Primer layer 26...adhesive layer 30…Transfer target (e.g., exterior material)

Claims

1. A transfer sheet comprising a releasable substrate and a transfer layer, the transfer layer includes a surface protective layer and a primer layer; the surface protective layer is located between the releasable substrate and the primer layer, the surface protection layer contains a cured resin, a first ultraviolet absorber having an absorption peak at a first wavelength, a second ultraviolet absorber having an absorption peak at a second wavelength longer than the first wavelength, and a third ultraviolet absorber having an absorption peak at a third wavelength longer than the second wavelength; a difference between the second wavelength and the first wavelength is 10 nm or more; a difference between the third wavelength and the second wavelength is 10 nm or more; the third wavelength is in the range of 345 nm to 370 nm, a transfer sheet, wherein the content of the second ultraviolet absorber in the surface protective layer is greater than the content of the first ultraviolet absorber and greater than the content of the third ultraviolet absorber;

2. The transfer sheet according to claim 1 , wherein the difference between the third wavelength and the first wavelength is 40 nm or more and 100 nm or less.

3. the first ultraviolet absorber has a maximum absorption peak in the wavelength range of 270 nm or more and 380 nm or less at the first wavelength, the second ultraviolet absorber has a maximum absorption peak in the wavelength range of 270 nm or more and 380 nm or less at the second wavelength, The transfer sheet according to claim 1 or 2, wherein the third ultraviolet absorber has a maximum absorption peak in the third wavelength range of 270 nm or more and 380 nm or less.

4. The transfer sheet according to any one of claims 1 to 3, wherein the primer layer contains at least one resin component selected from vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-(meth)acrylic copolymer, chlorinated polyethylene, chlorinated polypropylene, urethane resin, (meth)acrylic resin, (meth)acrylic polyol resin, polystyrene, polyester, polyamide, butyral resin, nitrocellulose, and cellulose acetate.

5. The transfer sheet according to any one of claims 1 to 4, wherein the first ultraviolet absorber, the second ultraviolet absorber, and the third ultraviolet absorber are each independently a triazine-based ultraviolet absorber.

6. The transfer sheet according to any one of claims 1 to 5, wherein the surface protective layer contains the first ultraviolet absorber, the second ultraviolet absorber, and the third ultraviolet absorber in a total amount of 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the cured resin contained in the surface protective layer.

7. The transfer sheet according to any one of claims 1 to 6, wherein the surface protective layer contains, relative to 100 parts by mass of the cured resin contained in the surface protective layer, 0.1 parts by mass or more and 3 parts by mass or less of the first ultraviolet absorber, 0.1 parts by mass or more and 8 parts by mass or less of the second ultraviolet absorber, and 0.1 parts by mass or more and 3 parts by mass or less of the third ultraviolet absorber.

8. The transfer sheet according to any one of claims 1 to 7, wherein the primer layer contains an ultraviolet absorber.

9. The transfer sheet according to any one of claims 1 to 8, wherein the transfer layer further comprises a design layer.

10. The transfer sheet according to any one of claims 1 to 9, wherein the transfer layer further comprises an adhesive layer as a surface layer on the side opposite to the releasable substrate side.

11. The transfer sheet according to any one of claims 1 to 10, for transferring the transfer layer onto at least a part of the surface of an exterior material.

12. A transfer object; A weather-resistant article comprising: a surface protective film provided on at least a portion of the surface of the transfer object; A weather-resistant article, wherein the surface protective film is the transfer layer in the transfer sheet described in any one of claims 1 to 11, and the surface protective layer in the transfer layer constitutes at least a part of the surface layer of the weather-resistant article.

13. the transfer layer comprises an adhesive layer, or The weather-resistant article according to claim 12 , further comprising an adhesive layer provided between the transfer layer and the transfer-receiving body.

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