Transfer sheet and method for manufacturing a member using the transfer sheet

Abstract

To provide a transfer sheet having a surface protective layer which improves weather resistance of an article in long-term use outdoors etc.MEANS FOR SOLVING THE PROBLEM: The transfer sheet has a transfer layer on a release film. The transfer layer has a surface protective layer, a primer layer, and an adhesive layer in this order from the release film side. The surface protective layer contains ultraviolet absorbers. The content of the ultraviolet absorbers is 1 pt.mass or more and 10 pts.mass or less based on 100 pts.mass of a resin forming the surface protective layer. The content of an ultraviolet absorber having a melting point of 90°C or higher is 45 mass% or more based on the total amount of the ultraviolet absorbers.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a transfer sheet and a method for manufacturing a member using the transfer sheet. [Background technology]

[0002] BACKGROUND ART In the fields of household electrical appliances, automobile interior parts, miscellaneous goods, and the like, there are cases where the surface of an article is decorated or a surface protective layer is formed by a transfer method. The transfer method involves adhering a transfer sheet, which has a transfer layer formed on a substrate and which consists of a release layer, a surface protection layer, a design layer, an adhesive layer, etc., to an article to be transferred onto, and then peeling off the substrate to transfer only the transfer layer onto the surface of the article to be transferred onto, thereby achieving decoration.

[0003] As a transfer sheet for decorating the surface of an article, Patent Document 1 proposes a design transfer sheet including a design transfer layer releasably attached to a release layer. Furthermore, Patent Document 2 proposes a protective layer transfer sheet in which a transfer layer having a protective layer is formed on a substrate that is easily thermally deformed, as a transfer sheet for forming a protective layer on the surface of an article for the purpose of preventing scratches on the molded product, etc. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-120643 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-297460 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the transfer sheets of Patent Documents 1 and 2 are used outdoors, the patterns and other designs applied to the items tend to fade due to the effects of ultraviolet rays from sunlight, making it difficult to maintain the applied designs for a long period of time. Furthermore, in the transfer sheets of Patent Documents 1 and 2, the protective layer, etc., is easily deteriorated due to the influence of ultraviolet rays from sunlight, etc., and it is difficult to maintain the function of the protective layer, etc. for a long period of time, especially when used outdoors.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a transfer sheet having a surface protective layer that improves the weather resistance of an article when used outdoors for a long period of time, and a method for manufacturing a component that has excellent weather resistance when used outdoors for a long period of time. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides the following [1] to [4]. [1] A transfer sheet having a transfer layer on a release film, the transfer layer having a surface protection layer, a primer layer, and an adhesive layer in this order from the release film side, the surface protection layer containing an ultraviolet absorber, the content of the ultraviolet absorber relative to 100 parts by mass of resin forming the surface protection layer being 1 part by mass or more and 10 parts by mass or less, and the content of ultraviolet absorbers having a melting point of 90°C or more relative to the total amount of the ultraviolet absorbers being 45% by mass or more. [2] The transfer sheet according to [1], wherein the adhesive layer contains a colorant. [3] The transfer sheet according to [1] or [2], further comprising a decorative layer between the adhesive layer and the primer layer. [4] A method for manufacturing a component, comprising the following steps (1) and (2) in order: (1) A step of bringing the surface of the transfer layer side of the transfer sheet according to any one of [1] to [3] into close contact with an adherend. (2) A step of peeling off the release film of the transfer sheet from the tightly attached transfer sheet and adherend. [Effects of the Invention]

[0008] The present invention aims to provide a transfer sheet having a surface protective layer that improves the weather resistance of an article when used outdoors for a long period of time, and a method for manufacturing a component that has excellent weather resistance when used outdoors for a long period of time. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing one embodiment of a transfer sheet of the present invention. [Figure 2] FIG. 10 is a cross-sectional view showing another embodiment of the transfer sheet of the present invention. [Figure 3] 1 is a photographic image showing the appearance of the melting point measurement of the ultraviolet absorbent used in Examples and Comparative Examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Transfer sheet] The transfer sheet of the present invention has a transfer layer on a release film, and the transfer layer has, from the release film side, a surface protection layer, a primer layer, and an adhesive layer in this order, the surface protection layer contains an ultraviolet absorber, the content of the ultraviolet absorber relative to 100 parts by mass of resin forming the surface protection layer is 1 part by mass or more and 10 parts by mass or less, and the content of ultraviolet absorbers with a melting point of 90°C or more relative to the total amount of the ultraviolet absorbers is 45% by mass or more. By having the surface protective layer of the transfer layer of the transfer sheet of the present invention contain an ultraviolet absorber with a melting point of 90°C or higher in the above-mentioned content, bleeding out of the ultraviolet absorber is suppressed, and excellent weather resistance is obtained even when a component using the transfer sheet of the present invention is used in a harsh environment, particularly under harsh temperature conditions.

[0011] Although the mechanism by which UV absorbers are prone to bleed-out under harsh temperature conditions is unclear, it is speculated that this bleed-out occurs when the UV absorbers liquefy due to a temperature rise in the transfer layer of the transfer sheet and leak out of the surface protective layer. When the UV absorbers liquefy, they are more likely to bleed out of the surface protective layer. As the bleed-out progresses, the amount of UV absorber held by the transfer layer of the transfer sheet decreases, presumably resulting in a deterioration in weather resistance. Furthermore, even if the liquefied UV absorbers remain in the surface protective layer, once the temperature conditions under which the transfer layer of the transfer sheet is used fall below the melting point of the UV absorbers, the UV absorbers will liquefy and solidify in a state where adjacent UV absorbers aggregate together, resulting in clumps in the surface protective layer. This results in the UV absorbers losing their good dispersion in the surface protective layer and a deterioration in weather resistance.

[0012] The temperature conditions to which outdoor components are exposed during use repeatedly rise and fall throughout the day. This results in a cycle of (1) liquefaction of the UV absorber, (2) bleed-out of the liquefied UV absorber, (3) aggregation of a portion of the bled-out UV absorber, and (4) solidification of the aggregated UV absorber, resulting in the formation of lumps. Furthermore, as a result of the bleed-out UV absorber, the UV absorber that has come out from inside the surface protective layer of the transfer layer of the transfer sheet to the outermost surface of the surface protective layer is washed away by rain and gradually disappears from the transfer layer of the transfer sheet. This loss of UV absorber reduces the weather resistance of the transfer layer of the transfer sheet, further accelerating the deterioration of the transfer layer. The transfer sheet of the present invention can further suppress bleed-out of the UV absorber and provide the component with excellent weather resistance, even in components used in such environments.

[0013] Fig. 1 is a cross-sectional view showing one embodiment of the transfer sheet of the present invention. The transfer sheet 10 in Fig. 1 has a transfer layer 11 on a release film 1. The transfer layer 11 has, in order from the side in contact with the release film 1, a surface protection layer 2, a primer layer 3, and an adhesive layer 4.

[0014] Figure 2 is a cross-sectional view showing another embodiment of the transfer sheet of the present invention. The transfer sheet 10 in Figure 2 has a transfer layer 11 on a release film 1. The transfer layer 11 has, in order from the side in contact with the release film 1, a surface protection layer 2, a primer layer 3, a decorative layer 5, and an adhesive layer 4.

[0015] Although not shown in FIGS. 1 and 2, the transfer sheet 10 may further have a second release film on the surface of the adhesive layer 4 opposite to the release film 1, if necessary. Although not shown in FIGS. 1 and 2, the transfer layer 11 may further have other functional layers as needed.

[0016] [Release film] The release film is a layer that is releasably laminated on the transfer layer among the layers that make up the transfer sheet. The release film is peeled off from the transfer layer after the transfer layer has been transferred to an adherend such as a resin sheet.

[0017] The release film is preferably a heat-resistant plastic film that can be peelably laminated to the transfer layer in order to improve the processability of the transfer sheet in the transfer step. Examples of plastic films used as release films include polyester resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate, polyamide resins such as nylon 6 and nylon 66, and polyimide resins. Of these, polyester resins are preferred, and among polyester resins, polyethylene terephthalate is particularly preferred.

[0018] The thickness of the release film is not particularly limited, but in order to improve the handleability of the transfer sheet, it is preferably 10 μm or more and 200 μm or less, more preferably 15 μm or more and 150 μm or less, and even more preferably 20 μm or more and 100 μm or less.

[0019] [Transfer layer] The transfer layer of the present invention is a layer that is transferred to an adherend, and has the role of imparting a predetermined function to the surface of the adherend. The transfer layer of the transfer sheet of the present invention has at least a surface protective layer, a primer layer, and an adhesive layer in this order from the release film side. In addition, the transfer layer of the transfer sheet preferably further has a decorative layer to impart design properties to the member.

[0020] The transfer layer may further include other functional layers, such as an antiglare layer, an antifouling layer, a stress relaxation layer, an antistatic layer, a gas barrier layer, an antifogging layer, and a transparent conductive layer.

[0021] (Surface protective layer) The transfer sheet of the present invention has a surface protective layer on the transfer layer. The surface protective layer in the present invention is a layer formed to impart durability, such as weather resistance, to the transfer layer of the transfer sheet of the present invention. Other durability requirements for the surface protective layer include resistance to contamination by various substances such as mud, scratch resistance, etc.

[0022] The surface protective layer of the present invention must contain an ultraviolet absorber in an amount of 1 to 10 parts by weight per 100 parts by weight of the resin forming the surface protective layer. If the ultraviolet absorber content is less than 1 part by weight, the ultraviolet absorber will not perform satisfactorily, and weather resistance will not be imparted to the transfer layer of the transfer sheet. If the ultraviolet absorber content exceeds 10 parts by weight, bleed-out will be more likely to occur and the strength of the surface protective layer may decrease, making it impossible to impart long-term weather resistance to the transfer layer of the transfer sheet. The lower limit of the content of the ultraviolet absorber in the surface protective layer is preferably 2 parts by weight or more, and more preferably 3 parts by weight or more, per 100 parts by weight of the resin forming the surface protective layer. The upper limit is preferably 6 parts by weight or less, more preferably 5 parts by weight or less, and even more preferably 4 parts by weight or less, per 100 parts by weight of the resin forming the surface protective layer.

[0023] The ultraviolet absorber contained in the surface protective layer of the present invention must have a content of ultraviolet absorbers having a melting point of 90°C or higher, as shown below, of 45% by mass or more relative to the total amount of ultraviolet absorbers contained in the surface protective layer. If the content of ultraviolet absorbers having a melting point of 90°C or higher is less than 45% by mass, the ultraviolet absorber will easily bleed out of the surface protective layer when used in an environment with large temperature changes, such as outdoors, and long-term weather resistance will not be imparted to the transfer layer of the transfer sheet. The proportion of the ultraviolet absorber at 90°C or higher relative to the total amount of ultraviolet absorbers contained in the surface protective layer is more preferably 55% by mass or higher, more preferably 65% ​​by mass or higher, even more preferably 75% by mass or higher, even more preferably 80% by mass, and particularly preferably 100% by mass.

[0024] The ultraviolet absorber used in the surface protective layer is not particularly limited as long as it has a melting point of 90° C. or higher, and either an organic or inorganic ultraviolet absorber can be used. The ultraviolet absorber is preferably an organic ultraviolet absorber in order to improve the transparency of the surface protective layer, dispersibility in the surface protective layer, and processability of the transfer sheet.

[0025] Preferred examples of organic ultraviolet absorbers include benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, triazine-based ultraviolet absorbers, and hydroxyphenyltriazine-based ultraviolet absorbers, and among these, hydroxyphenyltriazine-based ultraviolet absorbers are preferred.

[0026] Examples of inorganic ultraviolet absorbers include titanium dioxide, ferric oxide, zinc oxide, cerium oxide, and zirconium oxide, each having an average particle size of 380 nm or less, preferably 100 nm or less, and more preferably 50 nm or less.

[0027] The ultraviolet absorbents used in the surface protective layer may be any of the ultraviolet absorbents exemplified in this specification, which may be used alone or in combination.

[0028] Hydroxyphenyltriazine-based UV absorbers are UV absorbers with a hydroxyphenyltriazine structure. The hydroxyphenyltriazine structure has a molecular structure that makes it difficult for it to bleed out of the surface protective layer due to its steric hindrance. Furthermore, its melting point of 90°C or higher makes it difficult for bleed-out due to liquefaction to occur, and it remains well dispersed in the surface protective layer, resulting in excellent weather resistance. In the present invention, by using a hydroxyphenyltriazine-based ultraviolet absorber with a melting point of 90°C or higher, the occurrence of bleed-out due to liquefaction that may occur during use of a component using the transfer sheet of the present invention can be suppressed, and excellent weather resistance can be maintained.

[0029] The melting point of the ultraviolet absorber used in the surface protective layer is preferably 95° C. or higher, more preferably 100° C. or higher, and even more preferably 105° C. or higher, in order to further suppress bleed-out due to liquefaction and improve weather resistance. There is no particular upper limit, but in order to improve the processability of the surface protective layer, it is preferably 200° C. or lower, more preferably 160° C. or lower, and even more preferably 130° C. or lower. In this specification, the melting point of an ultraviolet absorber is the "temperature at which liquefaction begins." Specifically, the ultraviolet absorber is placed in a glass container, allowed to stand in an oven, and the oven is heated to a predetermined temperature for 1 hour. The melting point is defined as the temperature at which liquefaction begins.

[0030] More specifically, preferred examples of the hydroxyphenyltriazine-based ultraviolet absorber include those represented by the following general formula (1).

[0031] [ka]

[0032] In general formula (1), R 11 is a divalent organic group or a single bond, and R 12 is a monovalent organic group, -C(=O)OR 15 an ester group represented by -OC(=O)R 16or an acyloxy group represented by -OR 17 is an organyloxy group represented by the formula: 13 , R 14 , R 15 , R 16 and R 17 are each independently a hydrogen atom or a monovalent organic group, X is an oxygen atom or a single bond, and n 11 and n 12 are each independently an integer of 1 to 5. 13 and R 14 When there are multiple, they may be the same or different.

[0033] R 11 Preferred examples of the divalent organic group include aliphatic hydrocarbon groups such as alkylene groups and alkenylene groups, with alkylene groups being more preferred in order to improve the weather resistance of the transfer layer of the transfer sheet. The number of carbon atoms in these aliphatic hydrocarbon groups is preferably 1 or more, with the upper limit being preferably 20 or less, more preferably 12 or less, even more preferably 8 or less, and particularly preferably 4 or less. The alkylene group and alkenylene group may be linear, branched, or cyclic, with linear or branched being preferred.

[0034] R 12 Preferred examples of the monovalent organic group include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group, with an alkyl group being more preferred. The number of carbon atoms in the alkyl group is preferably 1 or more, more preferably 3 or more, and even more preferably 6 or more, with the upper limit being preferably 20 or less, more preferably 16 or less, and even more preferably 12 or less. The alkyl group and alkenyl group may be linear, branched, or cyclic, with linear or branched being preferred, and branched being more preferred.

[0035] R 13 and R 14 Examples of the monovalent organic group include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group, and aromatic hydrocarbon groups such as an aryl group and an arylalkyl group are preferred, with an aryl group being preferred.

[0036] R 13 and R 14 The number of carbon atoms in the alkyl group of the monovalent organic group is preferably 20 or less, more preferably 12 or less, even more preferably 4 or less, and particularly preferably 2 or less. 13 and R 14 As the monovalent alkyl group, a methyl group or an ethyl group is particularly preferred, and in consideration of availability, a methyl group is more preferred.

[0037] R 13 and R 14 The number of carbon atoms in the aryl group is preferably 6 or more, with the upper limit being preferably 20 or less, more preferably 12 or less, and even more preferably 10 or less. The number of carbon atoms in the arylalkyl group is preferably 7 or more, with the upper limit being preferably 20 or less, more preferably 12 or less, and even more preferably 10 or less.

[0038] R 15 , R 16 and R 17 Examples of the monovalent organic group include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. Aliphatic hydrocarbon groups such as an alkyl group and an alkenyl group are preferred, and an alkyl group is more preferred. 15 , R 16 and R 17 When is an alkyl group or an alkenyl group, the number of carbon atoms is preferably 2 or more, more preferably 4 or more, and the upper limit is preferably 20 or less, more preferably 16 or less, and even more preferably 12 or less.

[0039] The above R 11 , R 12 , R 13 , R 14 , R 15 , R 16 and R 17 The group may have a substituent such as a halogen atom, a hydroxyl group, an amino group, or an alkyl group having 1 to 4 carbon atoms.

[0040] Also, n 11 and n12 are each independently an integer of 1 or more and 5 or less, preferably an integer of 1 or more and 3 or less, and more preferably an integer of 1 or more and 2 or less. 11 and n 12 is an integer equal to or greater than 2, multiple R 13 and R 14 may be the same or different, and are preferably the same for reasons of availability.

[0041] Representative examples of hydroxyphenyltriazine-based ultraviolet absorbers having a melting point of 90° C. or higher include those represented by the following chemical formula (2), that is, those represented by the general formula (1) above, where R 11 is an ethylene group, R 12 -OC(=O)R 16 An acyloxy group (R 16 is a 3-heptyl group), R 13 and R 14 is a hydrogen atom. This hydroxyphenyltriazine-based ultraviolet absorber is available as a commercial product (manufactured by ADEKA Corporation, trade name "ADEKA STAB LA-46", melting point: 106°C).

[0042] [ka]

[0043] Representative examples of hydroxyphenyltriazine-based ultraviolet absorbers having a melting point of 90° C. or higher include those represented by the following chemical formula (3), that is, those represented by the general formula (1) above, where R 11 is a single bond, R 12 is an isooctyl group, R 13 and R 14 is a phenyl group, and n 11 and n 12 A preferred example is one in which the value is 1. This hydroxyphenyltriazine-based ultraviolet absorber is available as a commercial product (manufactured by BASF, trade name "Tinuvin 1600", melting point: 120°C).

[0044] [ka]

[0045] The reason why the use of the hydroxyphenyltriazine compound represented by the above chemical formula (3) can easily impart long-term weather resistance to the transfer layer of the transfer sheet is thought to be because the molecule does not contain structures such as ester bonds that are likely to become the starting point for decomposition or molecular structural mutation when used outdoors. The absence of structures such as ester bonds in the molecule makes decomposition and molecular structural mutation less likely to occur, making it easier to suppress bleed-out and facilitates imparting long-term weather resistance. Furthermore, due to the above characteristics, even if the content of the hydroxyphenyltriazine compound represented by the above chemical formula (3) in the surface protective layer is small, the transfer layer of the transfer sheet can be imparted with good weather resistance.

[0046] Representative examples of hydroxyphenyltriazine-based ultraviolet absorbers having a melting point of 90° C. or higher include those represented by the following chemical formula (4), that is, those represented by the general formula (1) above, where R 11 is a single bond, R 12 is a hexyl group, R 13 and R 14 is a hydrogen atom. This hydroxyphenyltriazine-based ultraviolet absorber is available as a commercial product (manufactured by BASF, trade name "Tinuvin 1577", melting point: 148°C).

[0047] [ka]

[0048] In the present invention, the UV absorber that can be used in the surface protective layer can be not only the UV absorber having a melting point of 90°C or higher, but also other UV absorbers, i.e., UV absorbers having a melting point of less than 90°C. In this case, conventionally commonly used UV absorbers can be used without particular limitation, and can be appropriately selected from UV absorbers such as benzotriazole-based UV absorbers, benzophenone-based UV absorbers, triazine-based UV absorbers, and hydroxyphenyltriazine-based UV absorbers. In this case, the other UV absorber is preferably a hydroxyphenyltriazine-based UV absorber. In other words, when a UV absorber other than a UV absorber having a melting point of 90°C or higher is used in combination, it is preferable to use a hydroxyphenyltriazine-based UV absorber having a melting point of less than 90°C as the other UV absorber. In particular, it is preferable to use a hydroxyphenyltriazine-based UV absorber having a melting point of 90°C or higher in combination with a hydroxyphenyltriazine-based UV absorber having a melting point of less than 90°C. When a hydroxyphenyltriazine-based ultraviolet absorber having a melting point of less than 90°C is used, the melting point of the ultraviolet absorber is preferably 55°C or higher, and more preferably 65°C or higher.

[0049] Generally, hydroxyphenyltriazine-based UV absorbers with melting points of 90°C or higher that are currently in practical use are often unable to fully absorb the entire wavelength range of UV rays that deteriorate the constituent materials of the transfer layers of various transfer sheets (surface protection layers, primer layers, adhesive layers, etc.). Therefore, it is preferable to use a UV absorber with a complementary UV absorption wavelength range in combination with a hydroxyphenyltriazine-based UV absorber with a melting point of 90°C or higher. Taking into account various performance factors such as UV absorption ability, low bleed-out properties, price, and colorless transparency, hydroxyphenyltriazine-based UV absorbers with a melting point of less than 90°C are suitable candidates for such UV absorbers with a complementary UV absorption wavelength range. Examples of such hydroxyphenyltriazine-based UV absorbers with melting points of less than 90°C include the hydroxyphenyltriazine compound represented by the following chemical formula (5). This UV absorber can effectively absorb UV wavelengths that contribute to the deterioration of polypropylene and propylene-based copolymers, particularly those containing propylene as the main monomer component, and can impart good weather resistance to components, for example, those containing polypropylene or propylene-based copolymers as adherends. This hydroxyphenyltriazine-based ultraviolet absorber is available as a commercial product (manufactured by BASF, trade name "Tinuvin 479", melting point: 70°C).

[0050] [ka]

[0051] With respect to the total amount of ultraviolet absorbers contained in the surface protective layer, the content of the hydroxyphenyltriazine ultraviolet absorber having a melting point of less than 90°C as described above is preferably less than 55% by mass, more preferably 45% by mass or less, and even more preferably 35% by mass or less. When the content of the hydroxyphenyltriazine ultraviolet absorber having a melting point of less than 90°C is less than 55% by mass, bleeding out of the ultraviolet absorber from the surface protective layer can be more easily prevented when used in environments with large temperature changes, such as outdoors, and long-term weather resistance can be more easily imparted to the transfer layer of the transfer sheet. On the other hand, in order to impart various properties of the hydroxyphenyltriazine-based ultraviolet absorber having a melting point of 90°C or higher, for example, the effect of complementing the ultraviolet absorption wavelength range, the lower limit of the content of the hydroxyphenyltriazine-based ultraviolet absorber having a melting point of less than 90°C is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, relative to the total amount of ultraviolet absorber contained in the surface protective layer.

[0052] In order to improve scratch resistance, the surface protective layer of the present invention preferably contains a cured product of a curable resin composition as a resin component. The proportion of the cured product of the curable resin composition relative to all resin components constituting the surface protective layer is preferably 70% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably 100% by mass.

[0053] Examples of the cured product of the curable resin composition include a cured product of a thermosetting resin composition or a cured product of an ionizing radiation curable resin composition. Among these, it is preferable to use a cured product of an ionizing radiation curable resin composition in order to improve the scratch resistance of the surface resin layer and the processability of the transfer sheet.

[0054] A thermosetting resin composition is a composition containing at least a thermosetting resin and is a resin composition that cures when heated. Examples of thermosetting resins include acrylic resins, urethane resins, urethane acrylic resins, phenolic resins, urea melamine resins, epoxy resins, unsaturated polyester resins, and silicone resins. These can be used alone or in combination. The thermosetting resin composition may also be one in which a curing agent such as an isocyanate-based curing agent or an epoxy-based curing agent has been added to these resins. Among these, acrylic resins are preferred, and acrylic resins to which an isocyanate curing agent has been added are more preferred.

[0055] Representative examples of ionizing radiation-curable resin compositions include electron beam-curable resin compositions and ultraviolet light-curable resin compositions, and among these, electron beam-curable resin compositions are preferred because they do not require a polymerization initiator and therefore have less odor, are less susceptible to coloring, etc. Furthermore, electron beam-curable resin compositions are also preferred in that, because the surface protective layer contains an ultraviolet light absorber, the crosslink density of the cured product layer can be easily increased and scratch resistance and contamination resistance can be easily improved.

[0056] 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 undergoes crosslinking and curing upon irradiation with ionizing radiation, and preferred examples include functional groups having an ethylenic double bond, such as a (meth)acryloyl group, a vinyl group, or an allyl group. In this specification, the term "(meth)acryloyl group" refers to an acryloyl group or a methcroyl group. In addition, in this specification, the term "(meth)acrylate" refers to an acrylate or a methacrylate. Furthermore, ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Typically, ultraviolet (UV) rays or electron beams (EB) are used, but it also includes other electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as alpha rays and ion beams. Specifically, the ionizing radiation curable compound can be appropriately selected from polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation curable resins.

[0057] As the polymerizable monomer, a (meth)acrylate monomer having a radically polymerizable unsaturated group in the molecule is preferred, and among them, a polyfunctional (meth)acrylate monomer is preferred. Here, "(meth)acrylate" means "acrylate or methacrylate." Examples of polyfunctional (meth)acrylate monomers include (meth)acrylate monomers having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group. In order to improve the processability of the transfer sheet and the scratch resistance and weather resistance of the surface protective layer, the number of functional groups in the polyfunctional (meth)acrylate monomer is preferably from 2 to 8, more preferably from 2 to 6, even more preferably from 2 to 4, and even more preferably from 2 to 3. These polyfunctional (meth)acrylates may be used alone or in combination of two or more.

[0058] Examples of polymerizable oligomers include (meth)acrylate oligomers having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group, such as urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers. Other polymerizable oligomers include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acrylate groups in the side chains of polybutadiene oligomers, silicone (meth)acrylate oligomers having polysiloxane bonds in the main chain, aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in their small molecules, and oligomers having cationically polymerizable functional groups in the molecules of novolac epoxy resins, bisphenol epoxy resins, aliphatic vinyl ethers, aromatic vinyl ethers, etc.

[0059] These polymerizable oligomers may be used alone or in combination of two or more. In order to improve the processability of the transfer sheet and the scratch resistance and weather resistance of the surface protective layer, one or more selected from urethane (meth)acrylate oligomer, epoxy (meth)acrylate oligomer, polyester (meth)acrylate oligomer, polyether (meth)acrylate oligomer, polycarbonate (meth)acrylate oligomer, and acrylic (meth)acrylate oligomer are preferred, one or more selected from urethane (meth)acrylate oligomer and polycarbonate (meth)acrylate oligomer are more preferred, and urethane (meth)acrylate oligomer is even more preferred.

[0060] The number of functional groups of these polymerizable oligomers is preferably 2 or more and 8 or less in order to improve the processing characteristics of the transfer sheet and the scratch resistance and weather resistance of the surface protective layer, with the upper limit being more preferably 6 or less, even more preferably 4 or less, and even more preferably 3 or less. Furthermore, the weight average molecular weight of these polymerizable oligomers is preferably 2,500 or more and 7,500 or less, more preferably 3,000 or more and 7,000 or less, and even more preferably 3,500 or more and 6,000 or less, in order to improve the processing characteristics of the transfer sheet and the scratch resistance and weather resistance of the surface protective layer. In this specification, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0061] In the ionizing radiation-curable resin composition, a monofunctional (meth)acrylate can be used in combination for the purpose of reducing the viscosity of the ionizing radiation-curable resin composition, etc. These monofunctional (meth)acrylates may be used alone or in combination of two or more kinds.

[0062] When the ionizing radiation curable compound is an ultraviolet curable compound, it is preferable to contain additives such as a photopolymerization initiator and a photopolymerization accelerator. The photopolymerization initiator may be one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzil dimethyl ketal, benzoyl benzoate, α-acyloxime ester, acylphosphine oxide, thioxanthones, and the like. The photopolymerization accelerator can reduce polymerization inhibition caused by air during curing and increase the curing rate, and examples thereof include one or more selected from p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, etc.

[0063] The surface protective layer may contain other additives as needed, as long as the effects of the present invention are not impaired. Examples of other additives that are preferably used include antioxidants, light stabilizers, organic particles, and inorganic particles.

[0064] The thickness of the surface protective layer is preferably 1.5 μm or more and 30 μm or less, more preferably 2 μm or more and 20 μm or less, and even more preferably 3 μm or more and 15 μm or less, in order to improve the processing characteristics of the transfer sheet and the scratch resistance and weather resistance of the surface protective layer.

[0065] (primer layer) The transfer sheet of the present invention has a primer layer in the transfer layer. The primer layer is formed between the surface protective layer described above and the adhesive layer described below. By forming the primer layer between the surface protective layer and the adhesive layer, it is possible to improve the adhesion between the layers contained in the transfer layer, and to improve the weather resistance and durability of the transfer layer.

[0066] The primer layer preferably contains a cured product of a curable resin composition in order to improve the processability of the transfer sheet and the adhesion between the layers contained in the transfer layer.

[0067] As the cured product of the curable resin composition contained in the primer layer, the cured product of the curable resin composition exemplified for the surface protective layer can be used. Among them, in order to improve the adhesion between the layers contained in the transfer layer, it is preferable to contain a cured product of a thermosetting resin composition, and among these, a cured product of a thermosetting resin composition containing an acrylic resin, a urethane resin, or a urethane acrylic resin is more preferable, and a cured product of a thermosetting resin composition obtained by crosslinking and curing an acrylic resin, a urethane resin, or a urethane acrylic resin with an isocyanate curing agent is even more preferable.

[0068] The primer layer may contain other additives as needed, as long as they do not impair the effects of the present invention. As other additives, for example, ultraviolet absorbers, antioxidants, light stabilizers, organic particles, inorganic particles, etc. are preferably used. In addition, as the ultraviolet absorbers, the ultraviolet absorbers exemplified in the surface protective layer can be suitably used.

[0069] The thickness of the primer layer is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 6 μm or less, in order to improve the processability of the transfer sheet and the adhesion between the layers contained in the transfer layer.

[0070] (adhesive layer) The adhesive layer is a layer that comes into contact with the adherend and is formed, for example, to improve adhesion to the adherend, among the layers that constitute the transfer layer of the transfer sheet.

[0071] The adhesive layer may be any of a pressure-sensitive adhesive layer, a curing adhesive layer, and a heat-sensitive adhesive layer, and among these, a heat-sensitive adhesive layer is preferred in order to improve the processability of the transfer sheet and the adhesion between the transfer layer of the transfer sheet and the adherend.

[0072] When the adhesive layer is a pressure-sensitive adhesive layer, it preferably contains a pressure-sensitive adhesive. The adhesive may be selected appropriately from acrylic, urethane, silicone, rubber, and other adhesives.

[0073] When the adhesive layer is a curable adhesive layer, it is preferable that the adhesive layer contains a thermosetting adhesive. The thermosetting adhesive is preferably one that contains a composition that has the property of crosslinking due to a chemical reaction caused by heat, and examples thereof include two-component curing urethane adhesives, polyester urethane adhesives, polyester urethane adhesives, acrylic adhesives, polyester adhesives, polyamide adhesives, polyvinyl acetate adhesives, epoxy adhesives, rubber adhesives, etc. The urethane resin that constitutes the two-component curing urethane adhesive is a polyurethane that uses polyol (polyhydric alcohol) as the main component and isocyanate as the crosslinking agent (curing agent).

[0074] When the adhesive layer is a heat-sensitive adhesive layer, the adhesive layer preferably contains a thermoplastic resin. Examples of thermoplastic resins include acrylic resins, urethane resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymers, styrene-acrylic copolymers, polyester resins, amide resins, cyanoacrylate resins, and epoxy resins, which can be used alone or in combination. Among these, acrylic resins are preferred in order to improve the processability when forming a member using the transfer sheet and the adhesion between the transfer layer of the transfer sheet and the adherend.

[0075] The weight-average molecular weight of the thermoplastic resin is preferably 10,000 to 200,000, more preferably 50,000 to 150,000, and more preferably 80,000 to 120,000. When the weight-average molecular weight of the thermoplastic resin composition is within the above range, the coating suitability is improved, and the adhesive layer can be easily formed in a good condition. Furthermore, when a member is manufactured using the transfer sheet of the present invention, the adhesion between the adhesive layer and the adherend can be easily improved, and the durability of the member can be easily improved.

[0076] The thickness of the adhesive layer is preferably from 1 μm to 10 μm, more preferably from 2 μm to 8 μm, and even more preferably from 3 μm to 7 μm. When the thickness of the adhesive layer is within the above range, good adhesion between the adhesive layer and the adherend can be easily achieved when forming a member.

[0077] The transfer sheet of the present invention preferably contains a colorant in the adhesive layer. By including a colorant in the adhesive layer, the adhesive layer alone or in combination with a decorative layer (described later) can impart design features to the transfer layer of the transfer sheet.

[0078] The colorant is not particularly limited, and examples thereof include inorganic pigments such as carbon black (ink), iron black, titanium white, antimony white, yellow lead, titanium yellow, red iron oxide, cadmium red, ultramarine blue, and cobalt blue; organic pigments or dyes such as quinacridone red, isoindolinone yellow, nickel azo complex, phthalocyanine blue, and azomethine azo black; metal pigments such as flaky flakes of aluminum, brass, and the like; and pearlescent pigments such as flaky flakes of titanium dioxide-coated mica and basic lead carbonate, and the like.

[0079] The content of the colorant is preferably 5 to 90 parts by mass, more preferably 15 to 80 parts by mass, and even more preferably 20 to 70 parts by mass, per 100 parts by mass of the resin constituting the decorative layer. By having the colorant content of 5 parts by mass or more, it is possible to easily impart design to the transfer layer of the transfer sheet, and by having the colorant content of 90 parts by mass or less, it is possible to easily suppress a decrease in adhesion between the adhesive layer and the adherend due to the addition of the colorant, and it is possible to easily form a transfer layer that is more durable when a part is formed.

[0080] (decorative layer) The transfer sheet of the present invention preferably has a decorative layer at any position on the transfer layer of the transfer sheet in order to improve the design. The location where the decorative layer is formed is preferably between the adhesive layer and the primer layer, or between the primer layer and the surface protection layer, in order to improve the weather resistance of the decorative layer, and more preferably between the adhesive layer and the primer layer in order to further improve the durability of the transfer layer.

[0081] The decorative layer may be formed on the entire surface of the transfer sheet, or may be formed on only a part of the surface.

[0082] Examples of the decorative layer include a colored layer formed by applying ink in a solid manner, a patterned layer formed by printing ink as a pattern, and a thin metal film. Examples of patterns (designs) that can be expressed by the decorative layer include wood grain patterns such as tree rings and vessel grooves on the surface of wooden boards; stone grain patterns on the surface of stone slabs such as marble and granite; fabric grain patterns on the surface of fabric; leather grain patterns on the surface of leather; tile patterns including grooves; brickwork patterns including grooves; sand grain patterns; pear-skin patterns; patterns consisting of an arrangement of multiple concave and convex stripes extending in parallel directions (so-called ``line-like concave and convex patterns'' or ``ray-carved patterns''); and abstract patterns such as geometric patterns, letters, figures, polka dots, and floral designs.

[0083] The ink used for the colored layer and the design layer is a mixture of a binder resin with an appropriate amount of a colorant such as a pigment or dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, an ultraviolet absorber, a light stabilizer, etc. The binder resin for the colored layer and the design layer is not particularly limited, and examples thereof include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin, cellulose acetate resin, etc. Also, various types of resins can be used, such as one-component curing resins and two-component curing resins containing a curing agent such as an isocyanate compound.

[0084] The colorant is not particularly limited, and the colorants exemplified for the adhesive layer can be suitably used. The content of the colorant is preferably 5 to 90 parts by mass, more preferably 15 to 80 parts by mass, and even more preferably 30 to 70 parts by mass, per 100 parts by mass of the resin constituting the decorative layer.

[0085] The color layer and the design layer may contain additives such as ultraviolet absorbers, light stabilizers, and colorants. The thickness of the colored layer and the patterned layer may be selected appropriately depending on the desired pattern, but in order to conceal the base color of the adherend and improve the design, it is preferably 0.5 μm or more and 20 μm or less, more preferably 1 μm or more and 10 μm or less, and even more preferably 2 μm or more and 5 μm or less.

[0086] Examples of metal thin films include thin films of simple metal elements such as gold, silver, copper, tin, iron, nickel, chromium, and cobalt; thin films of alloys containing two or more of the above metal elements; etc. Examples of alloys include brass, bronze, and stainless steel. The thickness of the metal thin film can be set to about 0.1 μm or more and 1 μm or less.

[0087] The above-mentioned surface protection layer, primer layer, adhesive layer and decorative layer can be formed, for example, by applying a coating liquid containing a composition for forming each layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating or comma coating, and then drying and curing the coating as necessary.

[0088] [Second release film] The transfer sheet of the present invention may further have a second release film on the surface of the adhesive layer opposite to the release film. In particular, when the adhesive layer is a pressure-sensitive adhesive layer, the transfer sheet of the present invention has a second release film, which makes it easier to prevent blocking when the transfer sheet is wound into a roll during production, and makes it easier to prevent the transfer sheet from accidentally sticking to other objects.

[0089] When defining the peeling strength between the peeling film and the transfer layer as P1 and the peeling strength between the second peeling film and the adhesive layer as P2, it is preferable that P2 < P1. By having P2 < P1, it becomes easier to peel the second peeling film before the peeling film. In addition, in this specification, the peeling strength can be measured in accordance with the 180-degree peeling test of JIS Z 0237:2009.

[0090] The second peeling film is not particularly limited as long as it can be peeled from the adhesive layer, and a plastic film is preferably used. As the plastic film used as the second peeling film, the same ones as those exemplified for the above-mentioned peeling film can be used. Among the exemplified plastic films, in order to improve the handling property of the transfer sheet, it is preferable to use a polyester resin, and among the polyester resins, it is particularly preferable to use polyethylene terephthalate.

[0091] It is preferable that the surface of the second peeling film in contact with the adhesive layer is subjected to a peeling treatment with a peeling agent or the like. As the peeling agent, known peeling agents such as fluorine-based release agents and silicone-based release agents can be used. By subjecting the second peeling film to a peeling treatment with a peeling agent or the like, it becomes easier to make the relationship between the peeling strength P1 and the peeling strength P2 be P2 < P1.

[0092] The thickness of the second peeling film is not particularly limited, but in order to improve the handling property of the transfer sheet, it is preferably 10 μm or more and 200 μm or less, more preferably 15 μm or more and 150 μm or less, and even more preferably 20 μm or more and 100 μm or less.

[0093] [Manufacturing method of transfer sheet] The manufacturing method of the transfer sheet of the present invention has at least a surface protection layer forming step, a primer layer forming step, and an adhesive layer forming step.

[0094] (Surface protection layer forming step) The surface protective layer forming step is a step of forming a surface protective layer on a release film. The surface protective layer can be formed by applying a composition for forming the surface protective layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating, or comma coating, drying the applied composition as needed, and curing the applied composition by irradiating it with ionizing radiation such as an electron beam.

[0095] (Primer layer formation process) The primer layer forming step is a step of forming a primer layer on the surface protective layer formed in the surface protective layer forming step. The primer layer can be formed by applying a composition for forming the primer layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating, or comma coating, and then drying and curing the composition as necessary.

[0096] (Adhesive layer formation process) The adhesive layer forming step is a step of forming an adhesive layer on the primer layer formed in the primer layer forming step. The adhesive layer can be formed by applying a composition for forming the adhesive layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating, or comma coating, and then drying and curing the applied composition as necessary.

[0097] (Decorative layer forming process) The method for producing a transfer sheet of the present invention preferably further includes a decorative layer forming step, if necessary. The decorative layer forming step is a step of forming a decorative layer on the layer that forms the transfer layer of the transfer sheet.

[0098] The decorative layer forming process is preferably carried out between the primer layer forming process and the adhesive layer forming process, or between the surface protection layer and the primer layer forming process, and more preferably between the primer layer forming process and the adhesive layer forming process. By carrying out the decorative layer forming step between the above steps, a decorative layer can be formed between the layers that make up the transfer layer of the transfer sheet, making it easier to improve the weather resistance of the decorative layer.

[0099] The decorative layer can be formed by applying the composition for forming the decorative layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating, or comma coating, and then drying and curing the composition as necessary.

[0100] [Mechanism of manufacturing components] A member using the transfer sheet of the present invention can be produced by transferring the transfer layer of the transfer sheet to an adherend using the transfer sheet of the present invention.

[0101] The adherend is not particularly limited, and resin, paper, nonwoven or woven fabric, wood, metal, nonmetallic inorganic material, etc. can be appropriately selected depending on the application. When a resin is used as the adherend, one or both sides of the transfer sheet may be subjected to a physical or chemical surface treatment such as oxidation or roughening, if desired, in order to improve the adhesion between the transfer layer of the transfer sheet and the adherend. Metals used for the steel sheet include metal materials such as iron, aluminum, and copper, which may be subjected to a surface treatment such as hot-dip galvanizing or electrogalvanizing. The shape of the adherend is not particularly limited, and may be a flat plate such as a sheet, or may have a three-dimensional shape such as a curved plate or a polygonal pillar.

[0102] The method for producing a member of the present invention includes at least the following steps (1) and (2) in this order. (1) A step of bringing the transfer layer side of the transfer sheet of the present invention into close contact with an adherend. (2) A step of peeling off the release film of the transfer sheet from the tightly attached transfer sheet and adherend.

[0103] An example of the above step (1) is a lamination method having the following steps (a1) and (a2) in order. (a1) A step of contacting and superimposing the transfer layer side of the transfer sheet onto an adherend on a flat plate. (a2) A step of applying heat and pressure from the release film side of the transfer sheet to bring the adherend on the flat plate and the transfer layer of the transfer sheet into close contact.

[0104] The steps (a1) and (a2) can be carried out by a lamination method using heat and pressure in combination with a roll transfer device or the like.

[0105] In step (a2), the lamination roll temperature of the roll transfer device is preferably 180°C or lower, more preferably 160°C or lower. By setting the lamination roll temperature to 180°C or lower, it becomes easier to prevent the transfer layer of the transfer sheet from softening more than necessary, and the transfer layer can be transferred to the adherend in good condition. Furthermore, the lower limit of the lamination roll temperature of the roll transfer device in step (a2) is not particularly limited as long as the transfer layer of the transfer sheet and the adherend are closely attached, but is usually 100°C or higher, preferably 110°C or higher, and more preferably 120°C or higher.

[0106] Another example of the above (1) is an in-mold molding method that requires the following steps (z1) to (z4) in order. (z1) A step of placing the transfer layer side of the transfer sheet described above facing the inside of the in-mold forming die. (z2) A step of injecting a resin into the in-mold molding die. (z3) A step of integrating the transfer sheet and the resin to bring the transfer layer of the transfer sheet and the resin into close contact with each other, thereby forming a resin molded body. (z4) A step of removing the resin molded body from the in-mold molding die.

[0107] Furthermore, when the adhesive layer of the transfer sheet described above is a curable adhesive layer, it is preferable to have the following step (3) after the above step (2) in order to promote curing of the adhesive layer. (3) Aging step for a predetermined time at a certain temperature.

[0108] The temperature condition for aging is preferably 70°C or lower, and more preferably 65°C or lower. By setting the temperature at 70°C or lower, the curing reaction of the adhesive layer etc. proceeds slowly, and sudden shrinkage associated with the curing reaction can be prevented. The lower limit of the temperature condition for aging varies depending on the configuration of the adhesive layer etc., but is usually 40°C or higher in order to promote the curing reaction of the thermosetting resin composition etc. contained in the adhesive layer. The aging time varies depending on the structure of the adhesive layer, etc., or the temperature conditions for aging, but is usually 12 hours or more, preferably 24 hours or more, more preferably 48 hours or more, and even more preferably 72 hours or more.

[0109] Furthermore, when the transfer sheet described above has a second release film on the surface of the adhesive layer opposite to the release film side, it is preferable to have the following step (0) before the above step (1). (0) A step of peeling off the second release film from the transfer sheet to expose the adhesive layer.

[0110] [Component] A member using the transfer sheet of the present invention can be obtained by the above-described method for producing a member. A component using the transfer sheet of the present invention has at least an adhesive layer, a primer layer, and a surface protective layer, in that order, on an adherend, the surface protective layer containing an ultraviolet absorber, the content of the ultraviolet absorber relative to 100 parts by mass of the resin forming the surface protective layer being 1 part by mass or more and 10 parts by mass or less, and the content of ultraviolet absorbers with a melting point of 90°C or higher relative to the total amount of the ultraviolet absorbers being 45% by mass or more. When a member is formed using the transfer sheet of the present invention, if the transfer sheet has a decorative layer, the member can further have a decorative layer.

[0111] A component using the transfer sheet of the present invention contains an ultraviolet absorber in the surface protective layer, and the content of the ultraviolet absorber relative to 100 parts by mass of the resin forming the surface protective layer is 1 part by mass or more and 10 parts by mass or less, and the content of ultraviolet absorbers with a melting point of 90°C or higher relative to the total amount of ultraviolet absorbers is 45% by mass or more, thereby enabling the component to have long-term weather resistance. [Example]

[0112] EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the embodiments described in the examples.

[0113] 1. Measurement and Evaluation 1-1.Measuring the melting point of UV absorbers The melting points of the UV absorbers used in the Examples and Comparative Examples were determined by placing the UV absorbers in a glass container, placing them in an oven, and heating the oven to a predetermined temperature for one hour. When liquefaction began, the predetermined temperature was recorded as the melting point of the UV absorber. Figure 3 shows photographs of the appearance of the UV absorbers LA-46 (UV absorber 1), Tinuvin 1600 (UV absorber 2), and Tinuvin 479 (UV absorber 3) used in the Examples and Comparative Examples when placed in a 70°C oven. Tinuvin 479 was clearly liquefied, and the temperature at which this state began to occur was recorded as the melting point. The melting point measurement results are summarized in Table 1.

[0114] 1-2. Evaluation of exterior weather resistance The members obtained in the examples and comparative examples were subjected to an accelerated weathering test using a metal halide lamp (MWOM) for 1,500 hours (a test in which one cycle consisted of 20 hours of ultraviolet irradiation under the irradiation conditions below, followed by 4 hours of condensation under the condensation conditions below, and the cycle was repeated). After the accelerated weathering test, the appearance of the members was visually inspected and evaluated according to the following criteria. The evaluation results are summarized in Table 1. The test equipment, irradiation conditions, and condensation conditions for the accelerated weathering test were as follows: <Appearance evaluation criteria> A: No changes in appearance were observed. B: A slight change in appearance such as a slight change in color was observed. C: Significant changes in appearance such as color change were observed.

[0115] <Test equipment> Manufactured by Daipla Wintes, product name "Daipla Metal Weather" <Irradiation conditions> Illuminance: 65mW / cm 2 Black panel temperature: 63°C, chamber humidity: 50%RH, time: 20 hours <Condensation conditions> Illuminance: 0mW / cm 2 , Humidity inside the tank: 98%RH, Time: 4 hours

[0116] 1-3. Weather resistance evaluation of interlayer adhesion The members obtained in the examples and comparative examples were subjected to an accelerated weathering test using a metal halide lamp (MWOM) for 500 hours under the same conditions as in 1-1 above. After the accelerated weathering test, adhesive tape (manufactured by Nichiban Co., Ltd., product name "Cellotape (registered trademark)") was applied to the surface of the surface protection layer side of the member, with an area of ​​2.5 cm x 2.5 cm, so that it protruded approximately 5 cm from the edge of the member. A peel test was then conducted by pinching the protruding portion of the applied adhesive tape and peeling it off at a 45° angle to the surface of the member. Based on the results of the peel test, interlayer adhesion was evaluated according to the following criteria. The evaluation results are summarized in Table 1. <Evaluation criteria for interlayer adhesion> A: No peeling was observed between the layers of the transfer sheet. B: Slight peeling was observed in part of the interlayer of the transfer sheet. C: Significant peeling was observed between the layers of the transfer sheet.

[0117] 1-4. Evaluation of bleed-out resistance The members obtained in the examples and comparative examples were left in an environment of 40°C and 90% RH for one week. After leaving the members, the appearances of the members were visually observed from the surface protective layer side, and the bleed-out resistance was evaluated according to the following criteria. The evaluation results are summarized in Table 1. <Evaluation criteria for bleed-out resistance> A: No change in appearance was observed. B: Slight changes in appearance such as whitening, gloss change, and precipitation of sheet components were observed. C: Significant changes in appearance were observed, such as significant whitening, change in gloss, and precipitation of sheet components.

[0118] 2. Preparation of transfer sheet and components Example 1 Ionizing radiation curable resin composition 1 having the following formulation was applied to one side of a release film made of untreated polyethylene terephthalate film (manufactured by Mitsubishi Chemical Corporation, trade name "Diafoil E130") having a thickness of 26 μm in an amount of 5 g / m. 2 The uncured resin layer was then cured by irradiation with an electron beam (applied voltage: 175 keV, 5 Mrad (50 kGy)), forming a surface protection layer with a thickness of 5 μm. <Ionizing radiation curable resin composition 1> Trifunctional urethane acrylate oligomer 100 parts by mass (Arakawa Chemical Industries, Ltd., product name "Beamset 550B", weight average molecular weight: 5000) UV absorber 1 (hydrophenyltriazine UV absorber): 2 parts by mass (Manufactured by ADEKA Corporation, trade name "ADEKA STAB LA-46", melting point: 106°C, compound represented by the above chemical formula (2)) UV absorber 2 (hydrophenyltriazine-based UV absorber): 2 parts by mass (BASF, product name: Tinuvin 1600, melting point: 120°C, compound represented by the above chemical formula (3))

[0119] Next, a polycarbonate-based urethane acrylic copolymer (weight average molecular weight: 50,000) was applied on the surface protective layer in a coating amount of 2.5 g / m2 after drying. 2 After application, the mixture was dried to form a primer layer having a thickness of 2.5 μm.

[0120] Next, an acrylic resin (PMMA, weight average molecular weight: 96,000) was applied on the primer in an amount of 5 g / m2 after drying. 2 After coating, the adhesive layer was dried to form a 5 μm thick heat-sealable adhesive layer. After forming the adhesive layer, the adhesive layer was aged at room temperature for 24 hours to obtain a transfer sheet of Example 1.

[0121] The adhesive layer of the transfer sheet of Example 1 obtained above was placed opposite one side of the adherend, a polycarbonate plate (thickness: 2 mm, manufactured by AGC Corporation, product name "Carbo Polish"), and laminated. Then, using a laminator (manufactured by ACO Brands Japan, product name "Desktop Roll Laminator B316A3"), heat and pressure were applied from the transfer sheet side at a lamination roll temperature of 160°C and a conveyance speed of 0.5 m / min, to bring the transfer layer of the transfer sheet into close contact with the adherend. Next, the release film was peeled off from the tightly attached transfer sheet and adherend, to obtain the member of Example 1.

[0122] Examples 2 to 4 Transfer sheets and members of Examples 2 to 4 were obtained in the same manner as in Example 1, except that the type and amount of the ultraviolet absorber in the surface protective layer were changed to those shown in Table 1.

[0123] (Comparative Examples 1 to 3) Transfer sheets and members of Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the type and amount of the ultraviolet absorber in the surface protective layer were changed to those shown in Table 1.

[0124] [Table 1]

[0125] The ultraviolet absorbents 1 to 3 in Table 1 are as follows. UV absorber 1 (hydrophenyltriazine UV absorber): ADEKA Corporation, product name "ADEKA STAB LA-46", melting point: 106℃ (Compound represented by the above chemical formula (2)) UV absorber 2 (hydrophenyltriazine UV absorber): BASF, product surface "Tinuvin 1600", melting point: 120℃ (Compound represented by the above chemical formula (3)) UV absorber 3 (hydrophenyltriazine UV absorber): BASF, product name "Tinuvin 479", melting point: 70°C (Compound represented by the above chemical formula (5))

[0126] From the results in Table 1, it was confirmed that Examples 1 to 4, which have the characteristics of the present invention, have excellent weather resistance even under extremely harsh conditions, such as 500 to 1500 hours of accelerated testing using a metal halide lamp (MWOM), and therefore have excellent weather resistance even when used outdoors for long periods of time. On the other hand, Comparative Examples 1 and 2, in which the content of ultraviolet absorbers with a melting point of 90°C or higher relative to the total amount of ultraviolet absorbers used in the surface protective layer was low, could not be said to have excellent weather resistance even though a hydroxyphenyltriazine ultraviolet absorber (UVA3: Tinuvin 479) was used. Also, Comparative Example 3, in which the content of ultraviolet absorbers in the surface protective layer was too high, could not obtain sufficient crosslink density of the protective layer and ensure sufficient durability even though an ultraviolet absorber with a melting point of 90°C or higher was used, because the amount of ultraviolet absorber that could be retained in the surface protective layer was too large, and further bleed-out occurred, causing deterioration in appearance and potentially becoming the starting point for deterioration, so could not be said to have excellent weather resistance. [Industrial Applicability]

[0127] The transfer sheet of the present invention has excellent weather resistance and is therefore suitable for use as interior building components such as walls, ceilings, and floors, exterior building components such as exterior walls, roofs, eaves soffits, fences, and gates, various doors such as window frames and entrance doors, building fixtures or fittings such as handrails, baseboards, moldings, window frames, door frames, and moldings, as well as general furniture such as chests of drawers, shelves, and desks, kitchen furniture such as dining tables and sinks, decorative surface panels for cabinets of low-electrical appliances and office equipment, and interior or exterior vehicle components. Furthermore, members using the transfer sheet of the present invention are suitable for use in the above-mentioned various members, especially members used in environments exposed to direct sunlight. [Explanation of symbols]

[0128] 1 Release film 2 Surface protective layer 3 Primer layer 4 Adhesive layer 5 Decorative layer 10 Transfer sheet 11 Transfer layer

Claims

1. A transfer layer is provided on a release film, the transfer layer has a surface protection layer, a primer layer, and an adhesive layer in this order from the release film side; the surface protective layer contains an ultraviolet absorber, the content of the ultraviolet absorber relative to 100 parts by mass of the resin forming the surface protective layer is 1 part by mass or more and 10 parts by mass or less, The transfer sheet has a content of the ultraviolet absorber having a melting point of 90°C or higher of 45% by mass or more relative to the total amount of the ultraviolet absorbers.

2. The transfer sheet of claim 1 , wherein the adhesive layer comprises a colorant.

3. The transfer sheet according to claim 1 or 2, further comprising a decorative layer between the adhesive layer and the primer layer.

4. A transfer sheet described in any one of claims 1 to 3, wherein the content of the ultraviolet absorber having a melting point of 90°C or higher relative to the total amount of the ultraviolet absorber is 55 mass% or more.

5. A transfer sheet described in any one of claims 1 to 4, wherein the melting point of the ultraviolet absorber having a melting point of 90°C or higher is 90°C or higher and 200°C or lower.

6. A transfer sheet described in any one of claims 1 to 5, wherein the ultraviolet absorber is a hydroxyphenyltriazine-based ultraviolet absorber.

7. A transfer sheet described in any one of claims 1 to 6, wherein the surface protection layer contains a cured product of a curable resin composition as a resin component.

8. A transfer sheet described in any one of claims 1 to 7, wherein the thickness of the surface protection layer is 1.5 μm or more and 30 μm or less.

9. A method for manufacturing a member, comprising the following steps (1) and (2) in order: (1) A step of bringing the transfer layer side of the transfer sheet according to any one of claims 1 to 8 into close contact with an adherend. (2) A step of peeling off the release film of the transfer sheet from the tightly attached transfer sheet and adherend.

Images