Transparent film and decorative plate

Abstract

The present invention provides a transparent film in which a surface protective layer has excellent adhesion to a lower layer, and which is excellent in surface hardness, scratch resistance, and processability, and the present invention provides a transparent film in which a pattern layer under the transparent film can be clearly visually recognized due to excellent transparency of the transparent film.　Provided is a transparent film comprising at least a transparent base material layer and a surface protective layer, said transparent film being characterized in that: the surface protective layer contains a crosslinkable and curable resin; in an infrared spectroscopic measurement of the surface protective layer, the peak height ratio ((A / B) × 100(%)) between A and B is 105-400%, where A is the height of a peak appearing at 855-1325 cm-1 and B is the height of a peak appearing at 1650-1800 cm-1; and, in the infrared spectroscopic measurement of the surface protective layer, the peak height ratio ((B / C) × 100(%)) between B and C is 1000-6000%, where C is the height of a peak appearing at 3200-3500 cm-1.

Description

Transparent films and decorative panels

[0001] This invention relates to transparent films and decorative panels.

[0002] In recent years, decorative laminates have been used for purposes such as protecting and decorating the surfaces of articles. Such decorative laminates are manufactured by forming a patterned layer on the surface of wood panels, plastic panels, etc., using printing methods such as inkjet printing.

[0003] The decorative laminates mentioned above are used for a variety of purposes, including decorative items, building materials, and furniture. Therefore, in actual use, a transparent film is laminated onto the surface of the decorative laminate to protect the patterned layer on its surface.

[0004] The transparent films used in the applications described above are applied to surfaces such as wooden boards and plastic boards, and are therefore subject to impact. For this reason, the surface of the transparent film requires surface hardness and scratch resistance. For this reason, a surface protective layer is required on the transparent film, and this protective layer must adhere to the underlying layer. In particular, films with a small number of polar groups may be used on the surface of the underlying layer, and the surface protective layer of the transparent film must also adhere to such films.

[0005] As a transparent film having a surface protective layer that adheres to the film, a hard-coat film has been proposed in which a hard-coat layer is provided on at least one side of the base film (see Patent Document 1).

[0006] However, the hard coat film provided in Patent Document 1 does not exhibit sufficient adhesion between the base film and the hard coat film when used in various applications, and there is room for improvement.

[0007] Furthermore, since transparent films are used by being attached to the surface of articles for decorative purposes, they need to conform to the shape of the article. For this reason, transparent films require processability that allows them to be processed to conform to the shape of the article. The hard coat film described in Patent Document 1 has the problem of poor processability because processability has not been considered.

[0008] Further, since the transparency film is laminated on the surface of the decorative board on which the pattern layer is formed, sufficient transparency is required so that the pattern layer can be clearly visually recognized. As a film for laminating on the surface of an article, an overlaminate film is proposed in which a protective layer is laminated on one surface and an adhesive layer is laminated on the other surface of a transparent polypropylene resin film containing a triazine-based ultraviolet absorber and a hindered amine-based light stabilizer (see Patent Document 2).

[0009] However, the overlaminate film of Patent Document 2 has not been sufficiently studied for transparency, and there is a problem that the pattern layer cannot be clearly visually recognized when the film is laminated on the pattern layer.

[0010] Therefore, there is a demand for the development of a transparency film in which the surface protective layer has excellent adhesion to the lower layer, excellent surface hardness, scratch resistance, and processability, and excellent transparency, so that the pattern layer under the transparency film can be clearly visually recognized.

[0011] Japanese Patent Application Laid-Open No. 2017-177667

[0012] An object of the present invention is to provide a transparency film in which the surface protective layer has excellent adhesion to the lower layer, excellent surface hardness, scratch resistance, and processability, and the present invention aims to provide a transparency film in which the pattern layer under the transparency film can be clearly visually recognized because of excellent transparency.

[0013] As a result of intensive studies, the present inventor has found that it is a transparency film having at least a transparency base material layer and a surface protective layer, the surface protective layer contains a crosslinking and curing type resin, and in the infrared spectroscopic measurement of the surface protective layer, 855 to 1325 cm －１ Let the height of the peak appearing at be A, and 1650 to 1800 cm －１ When the height of the peak appearing at is B, the peak height ratio ((A / B)×100 (%)) of A and B is 105% or more and 400% or less, and in the infrared spectroscopic measurement of the surface protective layer, 3200 to 3500 cm －１We have found that the above objective can be achieved by using a transparent film in which the peak height ratio of B to C ((B / C) × 100 (%)) is between 1000% and 6000%, where C is the peak height appearing in the signal. This led to the completion of the present invention.

[0014] In other words, the present invention relates to the following transparent film and decorative panel: 1. A transparent film having at least a transparent substrate layer and a surface protective layer, wherein the surface protective layer contains a cross-linked curable resin, and the infrared spectral measurement of the surface protective layer shows a wavelength of 855 to 1325 cm⁻¹. －１ Let A be the height of the peak that appears, between 1650 and 1800 cm. －１ When the peak height appearing is B, the peak height ratio of A to B ((A / B) × 100 (%)) is between 105% and 400%, and in the infrared spectroscopic spectral measurement of the surface protective layer, at 3200 to 3500 cm⁻¹ －１1. A transparent film characterized in that the peak height ratio of B to C ((B / C) × 100 (%)) is 1000% or more and 6000% or less, where C is the peak height appearing at 2. The transparent film according to item 1, wherein the peak height ratio of A to B is 110% or more and 300% or less, and the peak height ratio of B to C is 1300% or more and 5500% or less. 3. The transparent film according to item 1 or 2, wherein the crosslinked curable resin includes an ionizing radiation curable resin. 4. The transparent film according to item 3, wherein the ionizing radiation curable resin includes an acrylic resin having a (meth)acryloyl group. 5. The transparent film according to any one of items 1 to 4, wherein the surface protective layer includes at least one selected from the group consisting of antibacterial agents, antiviral agents, and allergen reducing agents. 6. The transparent film according to any one of claims 1 to 5, wherein the transparent substrate layer includes a thermoplastic resin layer, and the thermoplastic resin layer contains at least one thermoplastic resin selected from the group consisting of olefin resin, vinyl chloride resin, polyester resin, polycarbonate resin, and polyacrylic resin. 7. The transparent film according to any one of claims 1 to 6, wherein the transparent substrate layer has at least a transparent substrate sheet and a transparent resin layer in order from the side opposite to the surface protective layer. 8. The transparent film according to any one of claims 1 to 7, wherein the transparent substrate layer has an adhesive layer on the side opposite to the surface protective layer. 9. A decorative panel having the transparent film according to any one of claims 1 to 8 on a substrate.

[0015] The transparent film of the present invention exhibits excellent adhesion of the surface protective layer to the underlying layer, as well as superior surface hardness, scratch resistance, and processability. Furthermore, because the transparent film of the present invention has excellent transparency, the pattern layer beneath the transparent film can be clearly seen. Therefore, decorative panels laminated with the transparent film of the present invention can be used in various building materials, furniture, and the like.

[0016] It is a figure showing an example of the result of infrared spectroscopic measurement of the surface protective layer of the transparency film of the present invention. It is a figure explaining a method of determining the height of a peak in the infrared spectroscopic measurement of the surface protective layer of the transparency film of the present invention. It is a figure explaining a method of determining the height of a peak in the infrared spectroscopic measurement of the surface protective layer of the transparency film of the present invention. It is a figure showing an example of the layer structure of the transparency film of the present invention. It is a figure showing an example of the layer structure of the decorative board of the present invention. It is a figure showing an example of hydrogen bonding between molecules of a crosslinking and curing type resin. It is a schematic diagram showing a test method for the difficulty of fire spread. It is a schematic diagram showing a test method for the difficulty of fire spread.

[0017] 1. Transparency Film The transparency film of the present invention is a transparency film having at least a transparent base material layer and a surface protective layer, wherein the surface protective layer contains a crosslinking and curing type resin, and in the infrared spectroscopic measurement of the surface protective layer, the height of the peak appearing at 855 to 1325 cm －１ is designated as A, and when the height of the peak appearing at 1650 to 1800 cm －１ is designated as B, the peak height ratio ( (A / B)×100(%)) of A and B is 105% or more and 400% or less, and in the infrared spectroscopic measurement of the surface protective layer, when the height of the peak appearing at 3200 to 3500 cm －１ is designated as C, the peak height ratio ( (B / C)×100(%)) of B and C is 1000% or more and 6000% or less. The transparency film of the present invention has the above characteristics, so that the surface protective layer of the transparency film has excellent adhesion to the lower layer, and is excellent in surface hardness, scratch resistance, and processability. Further, the transparency film of the present invention has the above characteristics, so that it has excellent transparency, and the pattern layer under the transparency film can be clearly visually recognized. Therefore, the decorative board laminated with the transparency film of the present invention can be used for various applications such as various building materials and furniture.

[0018] As described above, in the infrared spectroscopic measurement of the surface protective layer of the transparency film of the present invention, the height of the peak appearing at 855 to 1325 cm －１ is designated as A, and the height of the peak appearing at 1650 to 1800 cm －１When the peak height appearing is B, the peak height ratio of A to B ((A / B) × 100 (%)) is between 105% and 400%, and in the infrared spectroscopic spectral measurement of the surface protective layer, at 3200 to 3500 cm⁻¹, －１ When the peak height appearing in the graph is denoted as C, the peak height ratio of B to C ((B / C) × 100 (%)) is between 1000% and 6000%. This will be explained using a diagram below.

[0019] Figure 1 shows an example of the results of infrared spectral (IR) measurement of the surface protective layer of the transparent film of the present invention. In Figure 1, A represents the peak due to ether bonding, B represents the peak due to ester bonding, and C represents the peak due to urethane bonding.

[0020] In this specification, the height of each peak is measured as follows: As shown in Figure 2, two base points b1 and b2 are taken for each peak, and a baseline bL is drawn by connecting the base points with a straight line. Next, a vertical line is drawn downward from the position p of the peak top, and the intersection point bp with the baseline bL is designated. The length h between p and bp is taken as the height of the peak.

[0021] Furthermore, as shown in Figure 3, if peak A has multiple peaks, the peak heights are measured as follows. That is, as shown in Figure 3, if there are two adjacent peaks, and the heights h1-1 and h2-1 from the valley between the two peaks to the peak apex are 0.010 Abs or greater, the two peak heights h1 and h2 are added together to determine the peak height. Note that in Figure 3, the peak with peak top p2 has adjacent peaks p1 and p3 on both sides, and there are two heights, h2-1 and h2-2, from the valley between the two peaks to the peak apex. In this case, the shorter height, h2-1, is used to determine whether it is 0.010 Abs or greater.

[0022] In this specification, the infrared spectroscopic spectrum of the surface protective layer can be measured using commercially available infrared spectroscopic spectroscopy equipment.

[0023] The transparent film of the present invention exhibits an infrared spectral measurement of the surface protective layer between 855 and 1325 cm⁻¹. －１ Let A be the height of the peak that appears, between 1650 and 1800 cm. －１ The peak height ratio of A to B ((A / B) × 100 (%)), where B is the peak height appearing in the sample, is 105% or more and 400% or less. If the peak height ratio of A to B is less than 105%, there are too many ester bonds in the surface protective layer, the surface protective layer becomes too hard, and the processability of the transparent film decreases. If the peak height ratio of A to B exceeds 400%, there are too many ether bonds, the surface protective layer becomes too soft, and the surface hardness and scratch resistance of the transparent film decrease. The peak height ratio of A to B is preferably 110% or more and 300% or less, and more preferably 150% or more and 250% or less.

[0024] The transparent film of the present invention exhibits a spectral range of 3200 to 3500 cm in infrared spectroscopic measurements of the surface protective layer. －１ When the peak height C is the peak height that appears, the peak height ratio of B to C ((B / C) × 100 (%)) is between 1000% and 6000%. If the peak height ratio of B to C is less than 1000%, there are too many urethane bonds in the surface protective layer, and the hydrogen bonds between the -N-H groups and -C=O groups in the urethane bonds increase excessively, as shown in Figure 6, making the surface protective layer too hard and reducing the processability of the transparent film. If the peak height ratio of B to C exceeds 6000%, there are too few urethane bonds in the surface protective layer, making the surface protective layer too soft and reducing the surface hardness and scratch resistance of the transparent film. The peak height ratio of B to C is preferably between 1300% and 5500%, and more preferably between 1500% and 5200%.

[0025] One adjustment method for adjusting the peak height ratio between A and B, and the peak height ratio between B and C, to within the above range is to change the formulation of the cross-linked curable resin used to form the surface protective layer. When the cross-linked curable resin formulation contains many ether bonds and few ester bonds, the peak height ratio between A and B increases. Conversely, when the cross-linked curable resin formulation contains few ether bonds and many ester bonds, the peak height ratio between A and B decreases. Also, when the cross-linked curable resin formulation contains many ester bonds and few urethane bonds, the peak height ratio between B and C increases. Conversely, when the cross-linked curable resin formulation contains few ester bonds and many urethane bonds, the peak height ratio between B and C decreases.

[0026] The layers of the transparent film of the present invention will be described in detail below. In the transparent film of the present invention, the surface is the so-called "front surface," which is the surface opposite to the surface that comes into contact with the substrate when the transparent film of the present invention is laminated onto a substrate and used, and is the surface that is visible after lamination. In this specification, the direction of the surface of the transparent film of the present invention may be referred to as "front" or "top," and the opposite side may be referred to as "back" or "bottom." In the following description, the lower and upper limits of a numerical range expressed by "~" mean "greater than or equal to or less than or equal to" (for example, α~β means α or greater and β or less).

[0027] Furthermore, the layer thickness in this specification is the value measured in areas of the transparent film that do not have any uneven shapes such as embossing or protruding fine particles.

[0028] (Layer structure of the transparent film of the present invention) The transparent film of the present invention only needs to have at least a transparent substrate layer and a surface protection layer, and it is preferable that the surface protection layer is located on the outermost surface of the transparent film. The specific configuration can be set as appropriate depending on the application of the transparent film. For example, as shown in Figure 4, a configuration having a transparent substrate layer 14 and a surface protection layer 13 can be cited. Also in Figure 4, the transparent substrate layer 14 has a layer structure in which, from the bottom (from the opposite side of the surface protection layer 13), a transparent substrate sheet 11, an adhesive layer (not shown), a transparent resin layer 12, and a surface protection layer 13 are in that order. Figure 5 shows a decorative panel of the present invention using the transparent film 1 of the present invention with the above layer structure. In Figure 5, a pattern layer 21 is formed on the surface of the substrate 2, and the transparent film 1 is laminated thereon. Hereinafter, a transparent film with such a layer structure will be specifically described as a representative example.

[0029] (Surface protective layer) The transparent film of the present invention comprises at least a transparent substrate layer and a surface protective layer. In this specification, the surface protective layer contains a cross-linked curable resin.

[0030] Examples of cross-linked curing resins include thermosetting resins and ionizing radiation curing resins (e.g., electron beam curing resins). In particular, from the viewpoint of scratch resistance due to high surface hardness, convex shape retention, and productivity, it is preferable that the surface protective layer contains an ionizing radiation curing resin, and it is even more preferable that the resin constituting the surface protective layer is an ionizing radiation curing resin.

[0031] Examples of thermosetting resins include unsaturated polyester resins, polyurethane resins (including two-component curing polyurethanes), epoxy resins, aminoalkyd resins, phenolic resins, urea resins, diallyl phthalate resins, melamine resins, guanamine resins, melamine-urea cocondensation resins, silicon resins, and polysiloxane resins.

[0032] The above resins may be given curing agents such as crosslinking agents and polymerization initiators, polymerization accelerators, etc. For example, isocyanates and organic sulfonates can be added to unsaturated polyester resins and polyurethane resins as curing agents, organic amines can be added to epoxy resins, and peroxides such as methyl ethyl ketone peroxide and radical initiators such as azoisobutylnitrile can be added to unsaturated polyester resins.

[0033] Methods for forming a surface protective layer with a thermosetting resin include, for example, applying a solution of the thermosetting resin using a coating method such as roll coating or gravure coating, and then drying and curing it.

[0034] Ionizing radiation-curable resins are not limited to resins that undergo a crosslinking polymerization reaction upon irradiation with ionizing radiation and transform into a three-dimensional polymer structure. For example, one or more prepolymers, oligomers, and monomers having polymerizable unsaturated bonds or epoxy groups in their molecules that can be crosslinked by irradiation with ionizing radiation can be used. Examples include acrylate resins such as urethane acrylate, polyester acrylate, and epoxy acrylate; silicon resins such as siloxane; polyester resins; and epoxy resins.

[0035] The ionizing radiation-curable resin preferably contains an acrylic resin having (meth)acryloyl groups. By including an acrylic resin having (meth)acryloyl groups as the ionizing radiation-curable resin, hydrogen bonds are formed between the molecules of the ionizing radiation-curable resin, further improving the surface hardness and scratch resistance of the surface protective layer.

[0036] Ionizing radiation includes visible light, ultraviolet light (near-ultraviolet, vacuum ultraviolet, etc.), X-rays, electron beams, and ion beams, but among these, ultraviolet light and / or electron beams are preferred.

[0037] Suitable ultraviolet light sources include ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arc lamps, blacklight fluorescent lamps, and metal halide lamps. The wavelength of the ultraviolet light is approximately 190 to 380 nm.

[0038] Various electron beam accelerators can be used as electron sources, such as Cockcroftwald type, Van de Graft type, resonant transformer type, insulated core transformer type, linear type, Dynamitron type, and high-frequency type. The electron beam energy is preferably around 100 to 1000 keV, and more preferably around 100 to 300 keV. The electron beam irradiation dose is preferably around 2 to 15 Mrad.

[0039] Ionizing radiation-curable resins can be sufficiently cured by irradiation with electron beams, but when curing by irradiation with ultraviolet light, it is preferable to add a photopolymerization initiator (sensitizer).

[0040] For resin systems having radically polymerizable unsaturated groups, at least one of the following photopolymerization initiators can be used: acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, Michler benzoyl benzoate, Michler ketone, diphenyl sulfide, dibenzyl disulfide, diethyl oxide, triphenylbiimidazole, isopropyl-N,N-dimethylaminobenzoate, etc. For resin systems having cationic polymerizable functional groups, at least one of the following can be used: aromatic diazonium salts, aromatic sulfonium salts, metallocene compounds, benzoin sulfonic acid esters, fryloxysulfoxonium diallylodosyl salts, etc.

[0041] The amount of photopolymerization initiator added is not particularly limited, but is generally about 0.1 to 10 parts by mass per 100 parts by mass of ionizing radiation-curable resin.

[0042] Furthermore, in recent years, the use of biomass-derived resins, which have a low environmental impact, has been explored in various fields. The resin forming the surface protective layer of the transparent film of the present invention can also contain biomass-derived components, and specifically, biomass polyolefins and the like can be used.

[0043] The surface protection layer may be a single layer or a multi-layer structure of two or more layers. In this invention, if the surface protection layer consists of multiple layers, each layer contains a cross-linked curable resin. Furthermore, when the surface protection layer consists of multiple layers, the infrared spectral measurement of the surface protection layer is performed by measuring the infrared spectral spectrum of the stacked surface protection layers starting from the outermost surface protection layer.

[0044] The thickness of the surface protective layer is not particularly limited as long as it does not hinder the effects of the present invention, but is preferably 1 to 200 μm, more preferably 1 to 100 μm, even more preferably 3 to 50 μm, and particularly preferably 4 to 40 μm.

[0045] The surface protective layer may contain fine particles. Examples of fine particles include inorganic fillers such as silica, aluminum oxide, silicon carbide, silicon dioxide, calcium titanate, barium titanate, magnesium pyroborate, zinc oxide, silicon nitride, zirconium oxide, chromium oxide, iron oxide, boron nitride, diamond, corundum, and glass fibers; and organic material powders or beads such as acrylic, cross-linked alkyl, cross-linked styrene, benzoguanamine resin, urea-formaldehyde resin, phenolic resin, polyethylene, and nylon. One or more types of the fine particles can be used.

[0046] The average particle size of the fine particles is preferably greater than or equal to the thickness of the surface protective layer, and in order to exhibit scratch resistance, it is preferably less than "thickness of the surface protective layer + 40 μm", and more preferably "thickness of the surface protective layer + 30 μm" or less.

[0047] The average particle diameter of fine particles can be measured by known methods such as laser diffraction, Coulter counter, and sedimentation. Note that the average particle diameter refers to the mode diameter.

[0048] The content of fine particles in the surface protective layer is preferably 3 to 50 parts by mass, and more preferably 5 to 30 parts by mass, per 100 parts by mass of the resin component forming the surface protective layer.

[0049] Silica has siloxane bonds (-Si-O-Si-), which are similar to ether bonds (-C-O-C-). Therefore, if the surface protective layer contains silica, it may affect the peak height A mentioned above. However, even if the surface protective layer contains silica, if the peak height ratio of peak height A to B ((A / B) × 100 (%)) is between 105% and 400%, the surface protective layer of the transparent film of the present invention can exhibit the desired performance.

[0050] Silicone may be added to the surface protective layer. When silicone is added to the surface protective layer, the amount of silicone added is preferably 0.1 to 1 part by mass, and more preferably 0.1 to 0.5 parts by mass, per 100 parts by mass of the resin (resin component) constituting the surface protective layer, from the viewpoint of achieving both ease of wiping and slipperiness.

[0051] The surface protective layer may contain various additives as needed, such as solvents, dyes, pigments and other colorants, fillers such as inorganic fillers, defoamers, leveling agents, thixotropy-imparting agents, flame retardants, antibacterial agents, antiviral agents, and allergen-reducing agents.

[0052] As an inorganic filler, it can be used as a means of imparting a predetermined surface property to the surface protective layer by incorporating an inorganic filler larger than the thickness of the surface protective layer into the surface protective layer. Furthermore, the inorganic filler can also be used as a matting agent, and by including the inorganic filler in the surface protective layer, it is expected that the hardening shrinkage of the surface protective layer will be suppressed. Therefore, in this invention, it is preferable that the inorganic filler is surface-treated (hydrophobic treatment). In addition, among these additives, it is preferable to include at least one selected from the group consisting of antibacterial agents, antiviral agents, and allergen reducing agents in the surface protective layer, which is the outermost layer, in order to easily obtain the effect.

[0053] Examples of inorganic fillers include silica, aluminum oxide, silicon carbide, silicon dioxide, calcium titanate, barium titanate, magnesium pyroborate, zinc oxide, silicon nitride, zirconium oxide, chromium oxide, iron oxide, boron nitride, diamond, corundum, and glass fibers.

[0054] The method for surface treatment (hydrophobic treatment) of inorganic fillers is not particularly limited and can be carried out by known methods. Examples include: hydrophobic treatment of inorganic fillers with a silicone oil-based treatment agent; treatment of inorganic fillers with an alkylsilazane-based treatment agent, a trimethylsilylating agent, and / or an alkoxysilane, followed by hydrophobic treatment of the inorganic fillers with the aforementioned silicone oil-based treatment agent; hydrophobic treatment of inorganic fillers with a silicone oil-based treatment agent, followed by further treatment with a trimethylsilylating agent or an alkylsilazane-based treatment agent; hydrophobic treatment of inorganic fillers with an alkoxysilane; treatment of inorganic fillers with an alkoxysilane, followed by further treatment with a silicone oil-based treatment agent, or a silicone oil-based treatment agent and an alkoxysilane; and treatment of inorganic fillers with dimergol siloxane, and / or trimethylsilanol or a cyclic siloxane. In addition to the hydrophobic treatment methods described above, other methods of hydrophobic treatment include treatment with various coupling agents such as silane coupling agents, titanate coupling agents, and aluminate coupling agents; surfactants such as phosphoric acid-based and fatty acid-based surfactants; and treatment with oils, stearic acid, etc. Hereinafter, all of the above-mentioned products for hydrophobic treatment of untreated inorganic fillers (for example, all of the treatment agents such as silicone oil-based treatment agents, silane coupling agents, surfactants, etc.) will be collectively referred to as hydrophobic treatment agents.

[0055] The method for hydrophobizing inorganic fillers with a hydrophobic treatment agent is not particularly limited and can be carried out by known methods. For example, a method of adding (e.g., spraying) a stock solution of the hydrophobic treatment agent or a hydrophobic treatment agent diluted in water or an organic solvent to untreated inorganic fillers (dry treatment method); a method of treating (e.g., immersing) untreated inorganic fillers in a stock solution of the hydrophobic treatment agent, an aqueous solution containing the hydrophobic treatment agent, or an organic solvent containing the hydrophobic treatment agent, and then drying them (wet treatment method); and so on. As a result of such treatment, part or all of the surface of the inorganic filler is (a) coated with the hydrophobic treatment agent, (b) adsorbs the hydrophobic treatment agent, or (c) is coated with and adsorbs the hydrophobic treatment agent (a combination of (a) and (b)). As a result, hydrophobized inorganic fillers are obtained. Note that one type of hydrophobic treatment agent may be used alone or in combination of two or more types.

[0056] The above-mentioned antibacterial agents include inorganic antibacterial agents and organic antibacterial agents. In particular, inorganic antibacterial agents are generally safer than organic antibacterial agents and are preferable because they also have superior durability and heat resistance. Inorganic antibacterial agents are antibacterial metals such as silver, copper, and zinc supported on various inorganic carriers. When included in a surface protective layer, the amount of antibacterial agent added is preferably 0.1 to 10 parts by mass per 100 parts by mass of the resin component of the surface protective layer, but the details can be adjusted as appropriate depending on the type of antibacterial agent.

[0057] The above-mentioned antiviral agents can generally be broadly classified into organic and inorganic types. Organic antiviral agents include quaternary ammonium salts, quaternary phosphonium salts, pyridines, pyrithiones, benzimidazoles, organic iodines, isothiazolins, anions, and ethers. Inorganic antiviral agents include metal ions such as silver, copper, and zinc supported on carriers such as zeolites, apatite, zirconia, glass, and molybdenum oxide. When included in a surface protective layer, the amount of antiviral agent added is preferably 0.1 to 10 parts by mass per 100 parts by mass of the resin component of the surface protective layer, but the details can be appropriately adjusted depending on the type of antiviral agent.

[0058] Among the above organic antiviral agents, benzimidazole-based antiviral agents, anionic-based antiviral agents, or ether-based antiviral agents that maintain their particle shape are particularly preferred. Here, maintaining the particle shape means that they exist in a granular state without dissolving in the composition that becomes the curable resin of the surface protective layer (ink before curing). Therefore, in the process of forming the surface protective layer, the particles of imidazole-based compounds, anionic-based compounds, or ether-based compounds tend to float to the surface, making it easier to unevenly distribute the particles of imidazole-based compounds, anionic-based compounds, or ether-based compounds to the outermost surface of the surface protective layer. By unevenly distributing the particles of imidazole-based compounds, anionic-based compounds, or ether-based compounds to the outermost surface of the surface protective layer, the amount of antiviral agent required to obtain the desired antiviral effect can be suppressed, thus making it easier to suppress the decrease in the scratch resistance of the surface protective layer.

[0059] The above-mentioned anionic antiviral agents preferably include, for example, styrene resin, styrene polymer derivative compounds, and unsaturated carboxylic acid derivative compounds. Furthermore, the above-mentioned styrene polymer derivative compounds and unsaturated carboxylic acid derivative compounds preferably contain at least one structure from among styrene, sodium sulfonate, acrylic acid, maleic acid, and fumaric acid, and more preferably contain all of these structures. This is because viruses can be broadly classified into two types based on whether or not they have an envelope, and it is thought that the structure of the antiviral agent that can effectively inhibit the activity of each type is different. Therefore, for example, if the expectation is to be effective only against influenza viruses, which are non-enveloped viruses, it is sufficient to include only styrene polymer derivative compounds, and in some cases, sufficient effect can be obtained by including only styrene resin.

[0060] Among the inorganic antiviral agents mentioned above, silver-based antiviral agents are preferred from the viewpoint of having no biotoxicity and excellent safety, and among them, phosphate-based glass silver-supported compounds or silver zeolite compounds, and molybdenum silver oxide double salt compounds are even more preferred because they exhibit antiviral performance even in small amounts, thus allowing for a reduction in the amount added.

[0061] When the above-mentioned silver-based antiviral agent is included in the surface protective layer, discoloration may occur depending on the surface protective layer (discoloration may occur due to heat and light in the state of the paint in which it is added, or due to heat and light after the surface protective layer has been formed). In this case, it is possible to improve the situation by adding UV inhibitors, light stabilizers, etc., in a timely manner. For example, with respect to the above-mentioned silver molybdenum oxide double salt compound, a discoloration improvement effect can be expected by using a benzotriazole compound.

[0062] The above-mentioned allergen reducing agent contains either an inorganic compound or an organic compound, and each may be used individually or mixed with two or more different types. The inorganic compound is preferably a material supporting a metal. When included in a surface protective layer, the amount of allergen reducing agent added is preferably 0.1 to 10 parts by mass per 100 parts by mass of the resin component of the surface protective layer, but the details can be appropriately adjusted depending on the type of allergen reducing agent.

[0063] A method for forming a surface protective layer containing an ionizing radiation-curable resin includes, for example, a method in which a solution (resin composition for forming a surface protective layer) containing (1) a resin such as an ionizing radiation-curable resin, and (2) other resins, fine particles, ultraviolet absorbers, antibacterial agents, and the above-mentioned various additives is applied by a coating method such as gravure coating or roll coating, and then the ionizing radiation-curable resin is cured to form the surface protective layer.

[0064] (Transparent Substrate Layer) The transparent film of the present invention comprises at least a transparent substrate layer and a surface protective layer. The transparent substrate layer is not particularly limited as long as it is transparent, can be laminated with the surface protective layer, and can form a transparent film.

[0065] The transparent substrate layer preferably includes a thermoplastic resin layer, such as a transparent substrate sheet or a transparent resin layer, as described later. Examples of thermoplastic resins included in the transparent thermoplastic resin layer include olefin resin, vinyl chloride resin, polyester resin, polycarbonate resin, and polyacrylic resin. These thermoplastic resins may be used individually or in mixtures of two or more.

[0066] The layer configuration of the transparent substrate layer is preferably such that, starting from the side opposite the surface protection layer, it has at least a transparent substrate sheet and a transparent resin layer. A specific example of the layer configuration of the transparent substrate layer is shown in Figure 4, in which the transparent substrate layer 14 has, from bottom to top, a transparent substrate sheet 11, an adhesive layer (not shown), and a transparent resin layer 12 in that order. In Figure 4, the surface protection layer 13 is laminated on top of the substrate layer 14. The following describes each layer of the substrate layer with such a layer configuration in an illustrative manner.

[0067] (Transparent base sheet) A transparent base sheet is a layer on which transparent resin layers, etc., are sequentially laminated on its surface (front side).

[0068] As the transparent base sheet, for example, a sheet (film) formed from a thermoplastic resin is preferred. Suitable thermoplastic resins include olefin resins, vinyl chloride resins, polyester resins, polycarbonate resins, polyacrylic resins, and the like.

[0069] More specifically, the thermoplastic resins mentioned above include polyethylene, ethylene-α-olefin copolymers, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymers, propylene-butene copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl acetate copolymer saponifies, ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester copolymers, and other olefin resins; polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, polycarbonate, polyethylene naphthalate, ionomers, acrylic acid ester polymers, methacrylic acid ester polymers, and the like. In recent years, the use of biomass-derived resins, which have a low environmental impact, has been explored in many fields, and the resin used to form the transparent base sheet of the transparent film of the present invention can also contain biomass-derived components. Specifically, biomass polyolefins can be used. The transparent base sheet is formed by using these resins individually or in combination of two or more types.

[0070] In this specification, "(meth)acrylic acid" means acrylic acid and / or methacrylic acid, and the same applies to other parts that are indicated with "(meth)".

[0071] The transparent substrate sheet may be colored as long as it is transparent. In this case, the thermoplastic resin described above can be colored by adding a coloring agent (pigment or dye). As coloring agents, inorganic pigments such as titanium dioxide, carbon black, and iron oxide, organic pigments such as phthalocyanine blue, and various dyes can be used. One or more of these can be selected from publicly known or commercially available products. The amount of coloring agent added should also be set appropriately according to the desired color so as not to impair transparency.

[0072] The transparent substrate sheet may contain various additives as needed, such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, UV absorbers, and light stabilizers.

[0073] In the transparent substrate sheet, the UV absorber, light stabilizer, and flame retardant can be the same as those used in the transparent resin layer described later, and in the same amounts.

[0074] The thickness of the transparent substrate sheet can be set appropriately depending on the application and method of use of the final product, but generally 20 to 300 μm is preferred.

[0075] The transparent substrate sheet may, if necessary, be subjected to corona discharge treatment on its surface (front side) to improve adhesion with laminated layers such as a transparent resin layer. The method and conditions for corona discharge treatment should be carried out according to known methods. In addition, if necessary, corona discharge treatment may be applied to the back surface of the transparent substrate sheet, or a primer layer may be formed on the back surface.

[0076] (Adhesive layer) To improve the adhesion between the transparent resin layer and the pattern layer, which will be described later, an adhesive layer may be formed on the pattern layer. The adhesive layer is preferably a transparent adhesive layer, and this transparent adhesive layer may include colorless transparent, colored transparent, or translucent.

[0077] The adhesive is not particularly limited, and any adhesive known in the field of transparent films can be used.

[0078] Adhesives known in the field of transparent films include, for example, thermoplastic resins such as polyamide resins, acrylic resins, and vinyl acetate resins, and thermosetting resins such as urethane resins. These adhesives can be used individually or in combination of two or more. Two-component curing polyurethane resins or polyester resins using isocyanate as a curing agent can also be used.

[0079] The above-mentioned known printing methods can be used to form the transparent adhesive layer.

[0080] The thickness of the transparent adhesive layer is not particularly limited, but the thickness after drying is about 0.1 to 30 μm, preferably about 1 to 20 μm.

[0081] (Transparent resin layer) The transparent film of the present invention comprises at least a transparent substrate layer and a surface protective layer.

[0082] The transparent resin layer is not particularly limited as long as it is transparent, and includes colorless transparent, colored transparent, translucent, etc. A thermoplastic resin is preferred as the resin constituting the transparent resin layer. Suitable thermoplastic resins include olefin resins, vinyl chloride resins, polyester resins, polycarbonate resins, polyacrylic resins, etc.

[0083] More specifically, the thermoplastic resins mentioned above include polypropylenes such as polyethylene, ethylene-α-olefin copolymers, homopolypropylene, and random polypropylene; olefin resins such as polymethylpentene, polybutene, ethylene-propylene copolymers, propylene-butene copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl acetate copolymer saponifies, ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester copolymers, and olefin-based elastomers; polyethylene terephthalate, polybutylene terephthalate, polyamide, ionomer, acrylic acid ester polymers, methacrylic acid ester polymers, polycarbonate, and cellulose triacetate. In recent years, the use of biomass-derived resins, which have a low environmental impact, has been explored in many fields, and the resin forming the transparent resin layer of the transparent film of the present invention can also contain biomass-derived components; specifically, biomass polyolefins can be used. The transparent resin layer can be formed using these resins individually or in combination of two or more types.

[0084] The transparent resin layer is preferably a transparent thermoplastic resin layer, more preferably an olefin-based resin such as polypropylene resin or polyethylene resin, and even more preferably the resin constituting the transparent resin layer is the above-mentioned olefin-based resin or ionomer-based resin.

[0085] The transparent resin layer may be colored as long as it remains transparent, but it is preferable not to include any coloring agents.

[0086] The transparent resin layer may further contain various additives as needed. Examples include lubricants such as silicone resin, wax, and fluororesin; colorants such as dyes and pigments; antioxidants; ultraviolet absorbers; light stabilizers; and flame retardants. The content of the above additives is not particularly limited, and for example, it may be 0.1% by mass or more and 10% by mass or less, with the transparent resin layer being 100% by mass.

[0087] The transparent resin layer preferably contains an ultraviolet absorber from the viewpoint of providing weather resistance.

[0088] Examples of UV absorbers include benzotriazole-based UV absorbers, benzophenone-based UV absorbers, and triazine-based UV absorbers. Among these, triazine-based UV absorbers are preferred. One or more types of UV absorbers can be used.

[0089] Among triazine-based UV absorbers, hydroxyphenyltriazine-based UV absorbers in which at least one organic group selected from hydroxyphenyl groups, alkoxyphenyl groups, and organic groups containing these groups is linked to a triazine ring are more preferred, and hydroxyphenyltriazine-based UV absorbers represented by the following general formula (A) are even more preferred. Because hydroxyphenyltriazine-based UV absorbers have a branched structure, they are expected to be less prone to bleeding out from the transparent resin layer, and thus provide superior weather resistance over a longer period.

[0090]

[0091] In general formula (A), R １１ R is a divalent organic group, １２ ha -C (=O) OR １５ The ester group shown is R １３ , R １４ and R １５ Each of these is an independently monovalent organic group, n １１ and n １２ Each of these is an independent integer between 1 and 5.

[0092] R １１ Examples of divalent organic groups include aliphatic hydrocarbon groups such as alkylene groups and alkenylene groups. From the viewpoint of weather resistance, alkylene groups are preferred, and the number of carbon atoms is preferably 1 to 20, more preferably 1 to 12, even more preferably 1 to 8, and particularly preferably 1 to 4. The alkylene group and alkenylene group may be linear, branched, or cyclic, but linear and branched are preferred.

[0093] Examples of alkylene groups having 1 to 20 carbon atoms include methylene groups, 1,1-ethylene groups, 1,2-ethylene groups, 1,3-propylene, 1,2-propylene, 2,2-propylene, and various other propylene groups (hereinafter, "various" refers to linear, branched, and their isomers), various butylene groups, various pentylene groups, various hexylene groups, various heptylene groups, various octylene groups, various nonylene groups, various decylene groups, various undecylene groups, various dodecylene groups, various tridecylene groups, various tetradecylene groups, various pentadecylene groups, various hexadecylene groups, various heptadecylene groups, various octadecylene groups, various nonadecylene groups, and various eicosilene groups.

[0094] R １３ and R １４ Examples of monovalent organic groups include alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, and arylalkyl groups, with aromatic hydrocarbon groups such as aryl groups and arylalkyl groups being preferred, and aryl groups being particularly preferred. Among these, R １３ and R １４ A phenyl group is preferred as the monovalent organic group.

[0095] The aryl group is preferably an aryl group having 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 10 carbon atoms, such as phenyl group, various methylphenyl groups, various ethylphenyl groups, various dimethylphenyl groups, various propylphenyl groups, various trimethylphenyl groups, various butylphenyl groups, and various naphthyl groups. The arylalkyl group is preferably an arylalkyl group having 7 to 20 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 7 to 10 carbon atoms, such as benzyl group, phenethyl group, various phenylpropyl groups, various phenylbutyl groups, various methylbenzyl groups, various ethylbenzyl groups, various propylbenzyl groups, various butylbenzyl groups, and various hexylbenzyl groups.

[0096] R １５Examples of monovalent organic groups include alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, and arylalkyl groups, with aliphatic hydrocarbon groups such as alkyl groups and alkenyl groups being preferred, and alkyl groups being more preferred. That is, R １２ Preferably, alkyl ester groups and alkenyl ester groups are used, with alkyl ester groups being more preferred.

[0097] Examples of alkyl groups include alkyl groups having 1 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and even more preferably 6 to 12 carbon atoms, such as methyl groups, ethyl groups, various propyl groups, various butyl groups, various pentyl groups, various hexyl groups, various octyl groups, various nonyl groups, various decyl groups, various undecyl groups, various dodecyl groups, various tridecyl groups, various tetradecyl groups, various pentadecyl groups, various hexadecyl groups, various heptadecyl groups, various octadecyl groups, various nonadecyl groups, and various eicosyl groups.

[0098] Examples of alkenyl groups include, preferably, alkenyl groups having 2 to 20 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 6 to 12 carbon atoms, such as vinyl groups, various propenyl groups, various butenyl groups, various pentenyl groups, various hexenyl groups, various octenyl groups, various nonenyl groups, various decenyl groups, various undecenyl groups, various dodecenyl groups, various tridecenyl groups, various tetradecenyl groups, various pentadecenyl groups, various hexadecenyl groups, various heptadecenyl groups, various octadecenyl groups, various nonadecenyl groups, and various icocenyl groups.

[0099] More specifically, hydroxyphenyltriazine compounds used as hydroxyphenyltriazine ultraviolet absorbers represented by general formula (A) include R １１ is an alkylene group having 1 to 20 carbon atoms, R １２ However, R １５ R is an alkyl ester group having 1 to 20 C12, １３ and R １４ is an aryl group having 6 to 20 carbon atoms, n １１ and n １２ A hydroxyphenyltriazine compound with a ratio of 1 is preferred, R１１ is an alkylene group having 1 to 12 carbon atoms, R １２ However, R １５ R is an alkyl ester group having 2 to 16 C12 １３ and R １４ is an aryl group having 6 to 12 carbon atoms, n １１ and n １２ A hydroxyphenyltriazine compound with 1 is more preferred, R １１ is an alkylene group having 1 to 8 carbon atoms, R １２ However, R １５ R is an alkyl ester group having 6 to 12 C12 C12, １３ and R １４ is an aryl group having 6 to 10 carbon atoms, n １１ and n １２ A hydroxyphenyltriazine compound with 1 is more preferred, R １１ is an alkylene group having 1 to 4 carbon atoms, R １２ However, R １５ R is an ester group which is an alkyl group having 8 carbon atoms, １３ and R １４ is a phenyl group, n １１ and n １２ A hydroxyphenyltriazine compound with a ratio of 1 is particularly preferred.

[0100] Examples of the above hydroxyphenyltriazine compounds include 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]phenol, 2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, and 2-ethyl-hexanoic acid-2-[4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-3-hydroxy- Examples include phenoxy-ethyl ester, octanoic acid-2-[4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-3-hydroxyphenoxy]-ethyl ester, 2,4,6-tris{2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)}-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-iso-octyloxyphenyl)-s-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-1-3-5-triazine, and mixtures thereof, modified products, polymers, derivatives, etc.

[0101] The amount of ultraviolet absorber is preferably 0.2 to 10.0 parts by mass, more preferably 0.5 to 5.0 parts by mass, and even more preferably 1.0 to 4.0 parts by mass, per 100 parts by mass of the resin component constituting the transparent resin layer.

[0102] Examples of light stabilizers include aromatic compounds, amine compounds, organic acid compounds, catechin compounds, and hindered amine compounds, with hindered amine compounds being preferred. Hindered amine compounds are those having a structure that includes a 2,2,6,6-tetramethylpiperidine skeleton within the molecule.

[0103] The amount of light stabilizer is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 8.0 parts by mass, and even more preferably 1.0 to 5.0 parts by mass, per 100 parts by mass of the resin component constituting the transparent resin layer. It is preferable that the light stabilizer contains a hindered amine compound within the above range.

[0104] Examples of the above-mentioned flame retardants include halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, aluminum-based flame retardants, antimony-based flame retardants, magnesium-based flame retardants, boron-based flame retardants, and zirconium-based flame retardants. From an environmental standpoint, non-halogen-based flame retardants are more preferably used. The above-mentioned flame retardants can be used individually or in combination of two or more types.

[0105] Examples of phosphorus-based flame retardants include phosphinate metal salt-based flame retardants and phosphazene-based flame retardants. Furthermore, regardless of the type, the content of the flame retardant is preferably 3 parts by mass or more, and preferably 30 parts by mass or less, per 100 parts by mass of the resin component constituting the transparent resin layer. By staying within this range, the flame retardancy of the transparent film is improved while suppressing the impairment of the required performance inherent in the transparent film.

[0106] The thickness of the transparent resin layer is usually around 20 to 200 μm, but it may exceed this range depending on the application of the transparent film.

[0107] (Primer layer) A primer layer may be provided on the transparent resin layer. The primer layer can be formed by applying a known primer to the surface of the transparent resin layer. Examples of primers include urethane resin primers made of acrylic-modified urethane resin (acrylic urethane resin), primers made of urethane-cellulose resin (for example, a resin made by adding hexamethylene diisocyanate to a mixture of urethane and nitrate), and resin primers made of a block copolymer of acrylic and urethane. Additives may be added to the primer as needed. Examples of additives include fillers such as calcium carbonate and clay, flame retardants such as magnesium hydroxide, antioxidants, lubricants, foaming agents, ultraviolet absorbers, and light stabilizers. The amount of additives can be appropriately set according to the product characteristics.

[0108] The amount of primer to be applied is not particularly limited, but is usually 0.1 to 100 g / m². ２ Preferably 0.1 to 50 g / m ２ It is to that extent.

[0109] The thickness of the primer layer is not particularly limited, but is usually 0.01 to 10 μm, preferably about 0.1 to 1 μm.

[0110] (Adhesive layer (backside primer layer)) The transparent substrate layer may have an adhesive layer (backside primer layer) on the side opposite to the surface protective layer. Having an adhesive layer on the transparent substrate layer is effective when laminating a transparent film with a substrate (adherent) to produce a decorative panel.

[0111] The adhesive layer can be formed by applying a known primer to a transparent substrate sheet. Examples of primers include urethane resin primers made of acrylic-modified urethane resin (acrylic urethane resin), primers made of urethane-cellulose resin (for example, a resin made by adding hexamethylene diisocyanate to a mixture of urethane and nitrate), and resin primers made of acrylic and urethane block copolymers. Additives may be added to the primer as needed. Examples of additives include fillers such as calcium carbonate and clay, flame retardants such as magnesium hydroxide, antioxidants, lubricants, foaming agents, UV absorbers, and light stabilizers. The amount of additives can be appropriately set according to the product characteristics.

[0112] The amount of primer to be applied is not particularly limited, but is usually 0.1 to 100 g / m². ２ Preferably 0.1 to 50 g / m ２ It is to that extent.

[0113] The thickness of the adhesive layer is not particularly limited, but is usually 10 to 200 μm, preferably 15 to 150 μm, and more preferably 20 to 80 μm.

[0114] (Transparent synthetic resin backer layer) A transparent synthetic resin backer layer (hereinafter also simply referred to as the "backer layer"; this is a synthetic resin layer for improving scratch resistance and mitigating the influence of the substrate (adhered material)) may be provided on the back surface of the transparent substrate sheet. The above scratch resistance refers particularly to resistance to dents caused by localized loads. The transparent film of the present invention has sufficient scratch resistance even without a backer layer, but various performances such as scratch resistance can be further enhanced by providing a backer layer.

[0115] The backer layer may be colored as long as it is transparent, but it is preferable not to include any coloring agents.

[0116] A suitable method for forming the backer layer is extrusion molding of molten resin, and for example, extrusion molding using a T-die is preferred.

[0117] Methods for bonding the back surface of a transparent substrate sheet to a backer layer include bonding the transparent substrate sheet and the backer layer obtained by extruding a molten resin by heat fusion, and bonding by providing an adhesive layer (and a primer layer if necessary) between the transparent substrate sheet and the backer layer.

[0118] The resin constituting the backer layer is not particularly limited as long as it exhibits transparency, but examples include thermoplastic resins such as polyethylene, polypropylene (PP), polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, polyethylene terephthalate, amorphous polyethylene terephthalate (A-PET), highly heat-resistant polyalkylene terephthalate (for example, polyethylene terephthalate in which part of the ethylene glycol is replaced with 1,4-cyclohexanedimethanol or diethylene glycol, the so-called trade name PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate (PBT), polycarbonate, polyarylate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, polyimide, polystyrene, polyamide, and ABS (acrylonitrile-butadiene-styrene copolymer). In recent years, the use of biomass-derived resins with low environmental impact has been explored in many fields, and the resin forming the backer layer of the transparent film of the present invention can also contain biomass-derived components, specifically, biomass polyolefins can be used. These resins can be used individually or in combination of two or more types.

[0119] The thickness of the backer layer can be set appropriately depending on the intended use and method of use of the final product, and is generally preferred to be between 100 and 800 μm. Among these, 100 to 600 μm is more preferred.

[0120] The backer layer may be subjected to known easy-adhesion treatments on the bonding surface, such as corona discharge treatment, plasma treatment, degreasing treatment, or surface roughening treatment, as needed. Furthermore, a primer layer may be provided on the back surface to improve adhesion to the adherend.

[0121] (Vesculling of various additives contained in each layer of the transparent film) The various additives added to each of the layers of the transparent film of the present invention (such as inorganic fillers added to the primer layer and surface protective layer) are preferably vesicled. The method for vesicling the various additives is not particularly limited and can be done by known methods, among which supercritical reverse-phase evaporation is preferred.

[0122] Vesicle formation methods include the supercritical reverse-phase evaporation method, as well as the Bangham method, extrusion method, hydration method, reverse-phase evaporation method, and freeze-thaw method. Briefly explaining these vesicle formation methods, the Bangham method involves placing chloroform or a chloroform / methanol mixed solvent in a container such as a flask, then adding phospholipids and dissolving them. After that, the solvent is removed using an evaporator to form a thin film of lipids, and after adding a dispersion of additives, vesicles are obtained by hydrating and dispersing with a vortex mixer. The extrusion method involves preparing a phospholipid solution of the thin film and obtaining vesicles by passing it through a filter instead of using a mixer as an external perturbation in the Bangham method. The hydration method is almost the same preparation method as the Bangham method, but instead of using a mixer, vesicles are obtained by gently stirring and dispersing. The reverse-phase evaporation method involves dissolving phospholipids in diethyl ether or chloroform, adding a solution containing additives to create a W / O emulsion, removing the organic solvent from the emulsion under reduced pressure, and then adding water to obtain vesicles. The freeze-thaw method uses cooling and heating as external perturbations, and vesicles are obtained by repeating this cooling and heating process.

[0123] The supercritical reverse-phase evaporation method is described in detail below. The supercritical reverse-phase evaporation method is a method for forming capsule-shaped vesicles in which the various additives acting as encapsulating materials are contained in a single layer of film by adding an aqueous phase containing various water-soluble or hydrophilic encapsulating materials to a mixture obtained by uniformly dissolving a substance that forms the outer film of vesicles in carbon dioxide in a supercritical state or under temperature or pressure conditions above the supercritical point. Supercritical carbon dioxide refers to carbon dioxide in a supercritical state above the critical temperature (30.98°C) and critical pressure (7.3773 ± 0.0030 MPa), while carbon dioxide under temperature or pressure conditions above the critical point refers to carbon dioxide under conditions where only the critical temperature or only the critical pressure exceeds the critical conditions. By this method, single-layer lamellar vesicles with a diameter of 50 to 800 nm can be obtained. Generally, a vesicle is a general term for a small vesicle with a closed, spherical membrane structure containing a liquid phase inside. In particular, those whose outer membrane is composed of biolipids such as phospholipids are called liposomes.

[0124] Examples of the phospholipids mentioned above include glycerophospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, egg yolk lecithin, hydrogenated egg yolk lecithin, soy lecithin, and hydrogenated soy lecithin, as well as sphingophospholipids such as sphingomyelin, ceramide phosphorylethanolamine, and ceramide phosphorylglycerol.

[0125] The outer film can also be composed of nonionic surfactants or dispersants such as mixtures of nonionic surfactants with cholesterol or triacylglycerols.

[0126] As the nonionic surfactants mentioned above, one or more of the following can be used: polyglycerin ether, dialkylglycerin, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, polyoxyethylene polyoxypropylene copolymer, polybutadiene-polyoxyethylene copolymer, polybutadiene-poly2-vinylpyridine, polystyrene-polyacrylic acid copolymer, polyethylene oxide-polyethylethylene copolymer, polyoxyethylene-polycaprolactam copolymer, etc.

[0127] The above-mentioned cholesterols may include one or more of the following: cholesterol, α-cholestanol, β-cholestanol, cholestan, desmosterol (5,24-cholestadien-3β-ol), sodium cholate, cholecalciferol, etc.

[0128] The outer membrane of the liposome described above may be formed from a mixture of phospholipid and a dispersant. In the transparent film of the present invention, by using liposomes formed from phospholipid for the outer membrane, the compatibility between the resin composition, which is the main component of each layer, and various additives can be improved.

[0129] (Method for manufacturing a transparent film) The transparent film of the present invention is obtained by forming at least a transparent substrate layer and a surface protective layer. For example, it can be obtained by laminating a transparent adhesive layer, a transparent resin layer and a primer layer on a transparent substrate sheet, and then forming a surface protective layer on the outermost surface.

[0130] Furthermore, when embossing a transparent film, it may be done either before or after forming the surface protective layer. For example, in a specific embodiment, 1) a transparent resin layer and a primer layer may be formed sequentially on a transparent substrate sheet, a surface protective layer may be formed, and finally embossing may be performed. In another specific embodiment, 2) a transparent resin layer and a primer layer may be formed sequentially on a transparent substrate sheet, embossing may be performed, and finally a surface protective layer may be formed. In yet another specific embodiment, 3) a transparent resin layer may be formed sequentially on a transparent substrate sheet, then embossing may be performed, followed by a primer layer, and finally a surface protective layer may be formed.

[0131] Embossing is performed, for example, at a film temperature of 120°C to 160°C and a density of 10 to 40 kg / cm². ２ The raised and recessed pattern can be transferred to the printed side of the transparent film using pressure.

[0132] 2. Decorative Panel The decorative panel of the present invention is a decorative panel having the above-mentioned transparent film on a substrate. It is sufficient that the transparent film is laminated on the substrate such that the surface protective layer of the transparent film becomes the outermost layer.

[0133] The lamination method is not limited; for example, a method of attaching a transparent film to a substrate using an adhesive can be employed. The adhesive can be appropriately selected from known adhesives depending on the type of substrate. Examples include polyvinyl acetate, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ionomer, as well as butadiene / acrylonitrile rubber, neoprene rubber, and natural rubber. These adhesives can be used individually or in combination of two or more.

[0134] (Substrate) The substrate (adhered material) is not limited, and the same materials as known decorative panels can be used. Examples include wood, metal, ceramics, plastics, glass, etc. In particular, the transparent film of the present invention can be suitably used on wood. Specific examples of wood include veneers, wood single-ply, wood plywood, wood fiberboard, particleboard, and medium-density fiberboard (MDF) made from various materials such as cedar, cypress, zelkova, pine, lauan, teak, and meranti.

[0135] (Patterned layer) The decorative panel of the present invention may have a patterned layer on the base material.

[0136] The pattern layer is used to apply a desired pattern (design) to the decorative panel, and the types of patterns are not limited. Examples include wood grain patterns, leather patterns, stone patterns, sand patterns, tile patterns, brick patterns, fabric patterns, geometric figures, letters, symbols, abstract patterns, etc.

[0137] The method for forming the pattern layer is not particularly limited. For example, it may be formed on the substrate surface by a printing method using an ink obtained by dissolving (or dispersing) a known coloring agent (dye or pigment) together with a binder resin in a solvent (or dispersion medium). From the viewpoint of reducing the VOCs of the decorative panel, an aqueous composition may also be used as the ink.

[0138] Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc oxide, red iron oxide, Prussian blue, and cadmium red; organic pigments such as azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments; metallic powder pigments such as aluminum powder and bronze powder; pearlescent pigments such as titanium dioxide-coated mica and bismuth oxide; fluorescent pigments; and luminescent pigments. These colorants can be used individually or in combination of two or more. These colorants may also be used with fillers such as silica, extender pigments such as organic beads, neutralizing agents, surfactants, etc.

[0139] As the binder resin, in addition to hydrophilic treated polyester-based urethane resins, polyester, polyacrylate, polyvinyl acetate, polybutadiene, polyvinyl chloride, chlorinated polypropylene, polyethylene, polystyrene, polystyrene-acrylate copolymer, rosin derivatives, alcohol adducts of styrene-maleic anhydride copolymer, and cellulose-based resins can also be used in combination. More specifically, for example, polyacrylamide resins, poly(meth)acrylic acid resins, polyethylene oxide resins, poly-N-vinylpyrrolidone resins, water-soluble polyester resins, water-soluble polyamide resins, water-soluble amino resins, water-soluble phenolic resins, and other water-soluble synthetic resins; water-soluble natural polymers such as polynucleotides, polypeptides, and polysaccharides can also be used. Furthermore, for example, modified natural rubber, synthetic rubber, polyvinyl acetate resins, (meth)acrylic resins, polyvinyl chloride resins, polyurethane-polyacrylic resins, etc., or mixtures of the above natural rubber, etc., and other resins can also be used. The above binder resins can be used individually or in combination of two or more types.

[0140] Examples of solvents (or dispersion media) include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ester-based organic solvents such as ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and 2-ethoxyethyl acetate; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, and propylene glycol; ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ether-based organic solvents such as diethyl ether, dioxane, and tetrahydrofuran; chlorine-based organic solvents such as dichloromethane, carbon tetrachloride, trichloroethylene, and tetrachloroethylene; and inorganic solvents such as water. These solvents (or dispersion media) can be used individually or in combination of two or more.

[0141] Furthermore, in recent years, the use of biomass-derived resins, which have a low environmental impact, has been explored in many fields, and the binder resin that forms the pattern layer of the decorative panel of the present invention can also contain biomass-derived components. For example, biomass-derived urethane (meth)acrylate can be used, and specifically, a binder resin can be made that contains urethane (meth)acrylate containing at least a polyol, an isocyanate compound, and hydroxy(meth)acrylate, and at least one component selected from the group consisting of the above polyol, isocyanate compound, and hydroxy(meth)acrylate is a biomass-derived component.

[0142] Printing methods used to form the pattern layer include, for example, gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, and inkjet printing. Furthermore, when forming a solid-color pattern layer covering the entire surface, various coating methods such as roll coating, knife coating, air knife coating, die coating, lip coating, comma coating, kiss coating, flow coating, and dip coating can be used. Other methods such as hand-painting, suminagashi (marbling), photography, transfer, laser beam lithography, electron beam lithography, partial metal deposition, and etching may also be used, or combined with other formation methods.

[0143] The thickness of the pattern layer is not particularly limited and can be set as appropriate according to the product characteristics, but the layer thickness is approximately 0.1 to 10 μm.

[0144] (Colored opaque layer) In the decorative panel of the present invention, a colored opaque layer may be further formed between the base material and the pattern layer.

[0145] The colored opacifying layer only needs to be able to conceal the base color of the substrate (adherent material) when the transparent film is joined to the substrate, and is usually formed to cover the substrate.

[0146] The above-mentioned known printing method can be used to form the colored opacity layer. Furthermore, the ink used to form the pattern layer can be used as is.

[0147] The application amount is 2-30 g / m². ２A range of this is desirable. The thickness of the colored opacity layer is usually about 0.1 to 20 μm, preferably about 1 to 10 μm.

[0148] The decorative panel of the present invention can be used, for example, as interior materials for buildings such as walls, ceilings, and floors; as surface decorative panels for building components such as window frames, doors, and handrails; and as surface decorative panels for furniture or cabinets for electrical equipment, office automation equipment, etc. In particular, the decorative panel of the present invention can be suitably used as a decorative material for building materials.

[0149] The present invention will be described in more detail below with reference to examples and comparative examples. However, the present invention is not limited to these examples.

[0150] Example 1 <Preparation of transparent film> A primer layer (backside primer layer) was provided on the back surface of a transparent substrate sheet made of a 60 μm thick transparent polypropylene film. Next, an adhesive layer was formed on the surface of the transparent substrate sheet. An 80 μm thick sheet of transparent polypropylene resin (transparent random polypropylene resin) was laminated on the adhesive layer by an extrusion lamination method to form a transparent resin layer. Next, a corona discharge treatment was applied to the surface of the transparent random polypropylene resin sheet, and then a primer layer was formed by coating it with a two-component curing urethane resin.

[0151] A surface protection layer-forming composition containing an ionizing radiation-curable resin including a urethane acrylate oligomer was applied to the entire surface of the primer layer using a gravure coating method to a coating thickness of 15 μm. Then, under conditions of an oxygen concentration of 200 ppm or less, the surface protection layer was formed by irradiating it with an electron beam using an electron irradiation device at an acceleration voltage of 165 keV and 5 mrad. Furthermore, the surface protection layer side was heated with an infrared non-contact heater to soften the transparent substrate sheet and the transparent resin layer, and then embossed by hot pressure to produce a transparent film.

[0152] Furthermore, as the urethane acrylate oligomer contained in the ionizing radiation-curable resin that forms the surface protective layer, a mixed resin was used, which was a mixture of the following urethane acrylate oligomers in the following proportions. A composition for forming the surface protective layer was prepared by adding the following ultraviolet absorber, light stabilizer, and additives in the following amounts to 100 parts by mass of the mixed resin. - Bifunctional urethane acrylate oligomer A (polyol component is polyester diol, Tg: 25°C, molecular weight 1500) - Hexafunctional aliphatic urethane acrylate oligomer B (Tg: 200°C or higher, molecular weight 1500, manufactured by Kyoeisha Chemical Co., Ltd., UA306H) Blending ratio (mass ratio) A:B = 80:20 - Hydroxyphenyl triazine-based UV absorber: Tinuvin 479 (manufactured by BASF Co., Ltd.) 3 parts by mass - Hindered amine-based light stabilizer: Sanol LS-3410 (manufactured by BASF Co., Ltd.) 3 parts by mass (additives) - Diluting solvent: Ethyl acetate 50 parts by mass - Gloss modifier: Inorganic filler L-121 (manufactured by AGC SI-TEC Inc.) 8 parts by mass

[0153] <Preparation of decorative panel> A medium-density fiberboard (MDF) with a thickness of 3 mm was prepared, and a pattern layer with a thickness of 2 μm was formed on one side of the MDF using an inkjet printer to prepare the base material. A two-component curing polyester resin with isocyanate as the curing agent was applied to the side having the adhesive primer layer (backside primer layer) for the transparent resin film to form an adhesive layer with a thickness of 30 μm, and the transparent film's adhesive primer layer and the pattern layer on the base material were laminated facing each other. Then, 10 kg / m ２ The decorative panels were manufactured by applying pressure and curing them at room temperature for three days.

[0154] Example 2 <Preparation of Transparent Film> (Nano-scale treatment of nucleating agent using supercritical reverse-phase evaporation) The nano-scale treatment of the nucleating agent using supercritical reverse-phase evaporation was carried out by the following method. First, 100 parts by mass of methanol, 82 parts by mass of a phosphate ester metal salt-based nucleating agent (ADEKA STAB NA-11, manufactured by ADEKA Corporation), and 5 parts by mass of phosphatidylcholine were placed in a high-pressure stainless steel container maintained at 60°C and sealed. Carbon dioxide was injected to bring the pressure to 20 MPa to a supercritical state. Next, 100 parts by mass of ion-exchanged water was injected while vigorously stirring. After stirring for 15 minutes while maintaining the temperature and pressure inside the container, carbon dioxide was released and the pressure was returned to atmospheric pressure to obtain a nucleating agent vesicle having an outer membrane made of phospholipid containing the nucleating agent.

[0155] (Formation of transparent resin layer) The polypropylene resin containing the nucleating agent vesicles obtained as described above (transparent random polypropylene resin) was extruded to a thickness of 80 μm to form a transparent resin layer.

[0156] (Formation of transparent substrate sheet and primer layer) Apply a two-component curing urethane ink (PET-E, Regiuser: manufactured by Dainichi Seika Co., Ltd.) as a primer to the surface of the 60 μm transparent substrate sheet that will be laminated with the substrate layer, at a rate of 1 g / m². ２ The surface was coated to form a primer layer on the back.

[0157] On the side of the transparent substrate sheet opposite to the primer layer on the back surface, the transparent resin layer obtained as described above is coated with a dry laminating adhesive (Takelac A540; manufactured by Mitsui Chemicals, Inc.; application amount 2 g / m²). ２ It was bonded using the dry lamination method via ().

[0158] (Formation of embossed pattern) Next, an embossed pattern was formed on the side of the transparent resin layer opposite to the transparent base sheet by pressing it with an embossing die roll.

[0159] (Formation of surface protective layer) Surface protective layer forming composition 1 (amount applied after drying (described as film thickness after drying; the same applies hereinafter) 5 μm) and surface protective layer forming composition 2 (amount applied after drying 10 μm) were sequentially laminated on the embossed surface described above, and by irradiating with ultraviolet light of a wavelength of 300 nm using an ultraviolet irradiation device, a surface protective layer consisting of surface protective layer 1 (lower layer) and surface protective layer 2 (upper layer) was formed, and a transparent film was produced.

[0160] [Composition 1 for Forming a Surface Protective Layer] Composition 1 for forming a surface protective layer was prepared by adding the following ultraviolet absorber, light stabilizer, and additives in the following amounts to 100 parts by mass of the main component. • Main component: Acrylic polyol (acrylic polyol containing urethane bonds, curing agent (forming urethane bonds through bonding with isocyanate containing N-H groups)) (glass transition temperature approximately 100°C, weight-average molecular weight Mw approximately 40,000, hydroxyl value 12) • Ultraviolet absorber: Tinuvin 399 (manufactured by BASF Co., Ltd.) 5 parts by mass • Light stabilizer: Tinuvin 123 (manufactured by BASF Co., Ltd.) 3 parts by mass (Additives) • Diluting solvent: Ethyl acetate 50 parts by mass • Gloss modifier: Inorganic filler L-121 (manufactured by AGC SI-TEC Inc.) 15 parts by mass • Curing agent: Duranate TAP-100 (manufactured by Asahi Kasei Corporation) 5 parts by mass

[0161] [Composition 2 for forming a surface protective layer] A mixed resin was prepared by blending the following resins in a mass ratio of A:B:C = 60:30:10. To 100 parts by mass of the mixed resin, the following light stabilizer, photopolymerization initiator, and additives were added in the amounts specified below to prepare composition 2 for forming a surface protective layer. - Resin A: Polyfunctional urethane acrylate oligomer having 3 to 15 functional groups - Resin B: Polyfunctional urethane acrylate oligomer having 2 to 9 functional groups - Resin C: 5 parts by mass of curing agent Duranate TAP-100 (manufactured by Asahi Kasei Corporation) per 100 parts by mass of acrylic polyol having a glass transition temperature of approximately 100°C, a weight-average molecular weight Mw of approximately 50,000, and a hydroxyl value of 15 - Light stabilizer: 3 parts by mass of Sanol LS765 (manufactured by BASF Co., Ltd.) - Photopolymerization initiator: Irgacure 907 (manufactured by BASF Co., Ltd.) 2.5 parts by mass - Photopolymerization initiator: Irgacure 184 (manufactured by BASF Co., Ltd.) 2.5 parts by mass (Additives) - Diluting solvent: Ethyl acetate 50 parts by mass - Gloss modifier: Inorganic filler L-121 (manufactured by AGC SI-TEC Inc.) 10 parts by mass

[0162] <Preparation of decorative panel> The decorative panel of Example 2 was prepared in the same manner as in Example 1, except that the transparent film prepared as described above was used.

[0163] Example 3 As the urethane acrylate oligomer contained in the ionizing radiation-curable resin that forms the surface protective layer, a mixed resin was used in which the following urethane acrylate oligomers were mixed in the following proportions. To 100 parts by mass of the mixed resin, an ultraviolet absorber, a light stabilizer, and additives in the same proportions as in Example 1 were added to prepare a composition for forming the surface protective layer. Otherwise, a transparent film and a decorative panel were prepared in the same manner as in Example 1. ・Bifunctional urethane acrylate oligomer A (polyol component is polyester diol, Tg: 25°C, molecular weight 1500) ・Bifunctional urethane acrylate oligomer B (polyol component is polyester diol, Tg: -55°C, molecular weight 5000) ・Hexafunctional urethane acrylate oligomer C (Tg: 200°C or higher, molecular weight 1500, UA306H manufactured by Kyoeisha Chemical Co., Ltd.) Mixing ratio (mass ratio) A:B:C = 60:10:30

[0164] Example 4 As the urethane acrylate oligomer contained in the ionizing radiation-curable resin that forms the surface protective layer, a mixed resin was used in which the following urethane acrylate oligomers were mixed in the following proportions. To 100 parts by mass of the mixed resin, an ultraviolet absorber, a light stabilizer, and additives in the same proportions as in Example 1 were added to prepare a composition for forming the surface protective layer. Otherwise, a transparent film and a decorative panel were prepared in the same manner as in Example 1. ・Bifunctional urethane acrylate oligomer A (polyol component is polyester diol, Tg: 25℃, molecular weight 1500) ・Hexafunctional urethane acrylate oligomer C (Tg: 200℃ or higher, molecular weight 1500, UA306H manufactured by Kyoeisha Chemical Co., Ltd.) Mixing ratio (mass ratio) A:B = 65:35

[0165] Example 5 A transparent polypropylene film with a thickness of 60 μm was used as the transparent base sheet. In addition, a transparent resin layer was formed by laminating a sheet of transparent polypropylene resin (transparent random polypropylene resin) with a thickness of 600 μm on top of the adhesive layer using an extrusion lamination method. The transparent film and decorative panel were manufactured in the same manner as in Example 1.

[0166] Example 6 A transparent acrylic film with a thickness of 50 μm was used as the transparent substrate sheet. After corona discharge treatment was applied to the surface of the transparent acrylic film, a primer layer was formed by coating it with a two-component curing urethane resin.

[0167] A surface protective layer-forming composition containing an ionizing radiation-curable resin containing a urethane acrylate oligomer was applied to the entire surface of the primer layer using a gravure coating method to a coating thickness of 5 μm. Then, under conditions of an oxygen concentration of 200 ppm or less, the surface protective layer was formed by irradiating with an electron beam using an electron irradiation device at an acceleration voltage of 165 keV and 5 mrad. As the urethane acrylate oligomer contained in the ionizing radiation-curable resin forming the surface protective layer, a mixed resin was used, which was a mixture of the following urethane acrylate oligomers in the following proportions. A surface protective layer-forming composition was prepared by adding an ultraviolet absorber, a light stabilizer, and additives in the same proportions as in Example 1 to 100 parts by mass of the mixed resin. Otherwise, a transparent film and a decorative panel were prepared in the same manner as in Example 1. - Bifunctional urethane acrylate oligomer A (polyol component is polyester diol, Tg: 25°C, molecular weight 1500) - Hexafunctional aliphatic urethane acrylate oligomer B (Tg: 200°C or higher, molecular weight 1500, manufactured by Kyoeisha Chemical Co., Ltd., UA306H) Blending ratio (mass ratio) A:B = 60:40

[0168] Example 7 As the urethane acrylate oligomer contained in the ionizing radiation-curable resin that forms the surface protective layer, a mixed resin was used in which the following urethane acrylate oligomers were mixed in the following proportions. To 100 parts by mass of the mixed resin, an ultraviolet absorber, a light stabilizer, and additives in the same proportions as in Example 1 were added to prepare a composition for forming the surface protective layer. Otherwise, a transparent film and decorative panel were prepared in the same manner as in Example 1. ・Bifunctional urethane acrylate oligomer A (polyol component is polyester diol, Tg: 25°C, molecular weight 1500) ・Bifunctional urethane acrylate oligomer B (polyol component is polyester diol, Tg: -55°C, molecular weight 5000) ・Hexafunctional urethane acrylate oligomer C (Tg: 200°C or higher, molecular weight 1500, UA306H manufactured by Kyoeisha Chemical Co., Ltd.) Mixing ratio (mass ratio) A:B:C = 65:32:3

[0169] Comparative Example 1 As a resin for forming a surface protective layer, the urethane acrylate-based UV-curable resin composition "TOMAX FA-3246" (solids content 40%, manufactured by Nippon Chemical Paint Co., Ltd.) and the urethane acrylate-based UV-curable resin "Art Resin UN-904" (solids content 100%, number of (meth)acryloyloxy groups: 10, manufactured by Negami Kogyo Co., Ltd.) were used as the main components, and the solids content ratio (mass ratio) of TOMAX FA-3246 and UN-904 was blended to 80 / 20. Irgacure 184 (photopolymerization initiator, manufactured by BASF) was added in an amount equivalent to 3 parts by mass relative to the solids content of the resin composition, and then diluted with butyl acetate until the solids content concentration in the coating for forming the surface protective layer was 30%, and the mixture was stirred thoroughly to prepare the coating for forming the surface protective layer. The prepared surface protective coating was applied to the surface of the primer layer using a bar coater, and then dried with hot air in an 80°C drying oven for 1 minute to form a coating layer with a thickness of 5.0 μm. Next, a UV irradiation device set at a height of 60 mm above the coated surface of the coating layer was used to irradiate it with a UV dose of 250 mJ / cm². ２ UV irradiation was performed under these conditions to cure and form a surface protective layer. Otherwise, the transparent film and decorative panel of Comparative Example 1 were prepared in the same manner as in Example 1.

[0170] The following measurements were performed using the transparent films and decorative panels prepared in the examples and comparative examples.

[0171] [IR Peak Height Ratio] The infrared spectral spectrum of the surface protective layer of the transparent film was measured using an infrared spectrophotometer (IRAffinity-1A, Shimadzu Corporation). On a spectral chart with absorbance on the vertical axis, the range was 855–1325 cm⁻¹. －１ The height of the peak that appears is A, 1650-1800 cm. －１ The peak that appears is B, 3200-3500 cm. －１ The peak height appearing was denoted as C, and the ratio of (A / B) × 100 and (B / C) × 100 were defined as the peak height ratio.

[0172] For measuring peak height, baselines were drawn for each wavelength range, and the length of the line connecting the peak apex to the baseline so that it was horizontal to the vertical axis was measured. If there were multiple peaks within a wavelength range, two adjacent peaks were considered "two peaks" if the difference between the peak and trough was 0.010 Abs or more, and the sum of the heights of these peaks was defined as the "peak height."

[0173] [Adhesion] A grid peel test was performed on the surface protective layer of the transparent film under JIS-K5600-5-6 conditions, specifically at 25°C and 50% RH. Specifically, a cutter knife was used to make 11 vertical and 11 horizontal cuts at 1mm intervals in a grid pattern on the surface protective layer of the transparent film, creating a total of 100 squares. Adhesive tape No. 252 manufactured by Sekisui Chemical Co., Ltd. was then applied to the grid, pressed evenly with a spatula, and peeled off at a 60-degree angle. After repeating the pressing and peeling process five times at the same location, the number of remaining layers of the surface protective layer was measured and evaluated according to the evaluation criteria below. For adhesion evaluation after environmental testing, the transparent film was left in a humid heat environment of 60°C and 90% RH for three weeks, and then the adhesion evaluation was performed at 25°C. Note that the vertical direction of the transparent film refers to the winding direction of the film roll (MD direction in the manufacturing equipment), and the horizontal direction of the transparent film refers to the width direction of the film roll (TD direction in the manufacturing equipment). (Evaluation criteria) ++: 100 units +: 95 units or more and 99 units or less -: 80 units or more and 94 units or less --: 79 units or less

[0174] [Scratch Resistance] 300g / m² of steel wool (Bonstar Co., Ltd. #0000) is applied to the surface protective layer of the transparent film. ２ A rubbing test was conducted under the condition of applying a load and performing 300 back-and-forth strokes. In accordance with the test method conforming to JIS-K5600-5-10, the surface of the transparent film with the protective layer side was rubbed 100 times back and forth with steel wool #0000 under a load of 1 kg, and the degree of scratching was evaluated according to the evaluation criteria below. (Evaluation Criteria) ++: No scratches +: Some scratches occur -: Many scratches occur

[0175] [Pencil Hardness] Pencil hardness was measured according to the test method conforming to JIS K5600-5-4. The hardness at which no scratches appeared on the surface was defined as pencil hardness.

[0176] [Bending Whitening] A test specimen was prepared by cutting a transparent film to 10 cm x 10 cm. The test specimen was sharply folded 180 degrees in both the vertical and horizontal directions (both vertical and horizontal) so that the surface protective layer side became the peak, and evaluated according to the evaluation criteria below. Note that the vertical direction of the transparent film is the winding direction of the transparent film roll (MD direction in the manufacturing equipment), and the horizontal direction of the transparent film is the width direction of the transparent film roll (TD direction in the manufacturing equipment). (Evaluation Criteria) ++: No whitening at all +: Some whitening, but not noticeable -: Whitening is present and noticeable

[0177] [Design Quality] The decorative laminate was visually inspected from the top side (surface protective layer side) and judged based on human perception whether the pattern of the patterned layer was clearly visible, according to the following evaluation criteria. Note that a rating of + or higher indicates that it is usable in actual use. (Evaluation Criteria) +++: Pattern is clearly visible ++: Pattern appears slightly cloudy, but the pattern is clearly visible +: Pattern appears slightly cloudy, and the pattern is not very clear, but it is visible -: Pattern is cloudy and not clearly visible

[0178] The results are shown in Table 1.

[0179]

[0180] From the results in Table 1, in Examples 1 and 2, the peak height ratio of A to B was 221 or 116, indicating that they have an appropriate amount of ester bonds. This resulted in an appropriate hardness for the surface protective layer, excellent scratch resistance, pencil hardness, and bending whitening, demonstrating that they possess a combination of these properties. Furthermore, in Examples 1 and 2, the peak height ratio of B to C was 1723 or 5057, indicating an appropriate amount of urethane bonds. As shown in Figure 6, it is thought that hydrogen bonds are formed between the ester bonds in the surface protective layer, resulting in a ++ rating for adhesion. Additionally, hydrolysis is suppressed, leading to a ++ rating for adhesion after environmental testing.

[0181] Furthermore, the results in Table 1 show that in Example 3, the surface protective layer was relatively softer compared to the surface protective layers of Examples 1 and 2. Specifically, the peak height ratio of A to B was larger compared to Examples 1 and 2, indicating fewer ester bonds, resulting in a softer surface protective layer. Although scratch resistance and pencil hardness were slightly inferior compared to Examples 1 and 2, bending whitening was more suppressed. Additionally, in Example 3, the peak height ratio of B to C was larger compared to Examples 1 and 2, indicating fewer urethane bonds, resulting in slightly inferior adhesion compared to Examples 1 and 2. Moreover, it was more susceptible to hydrolysis, resulting in slightly inferior adhesion after environmental testing.

[0182] Furthermore, as shown in Table 1, it was found that in Example 4, the surface protective layer was relatively harder and more brittle compared to the surface protective layers of Examples 1 and 2. Specifically, the peak height ratio of A to B was smaller compared to Examples 1 and 2, indicating a greater number of ester bonds, resulting in a harder surface protective layer. Although the pencil hardness was rated H, the bending whitening was rated +. In addition, in Example 4, the peak height ratio of B to C was smaller compared to Examples 1 and 2, indicating a greater number of urethane bonds. As shown in Figure 6, it is thought that hydrogen bonds are formed between the ester bonds in the surface protective layer, resulting in a ++ adhesion rating. Furthermore, hydrolysis is more suppressed, leading to a ++ adhesion rating after environmental testing.

[0183] Furthermore, as shown in Table 1, in Examples 1 to 7, when the decorative panel was observed visually from the top side (surface protective layer side), the pattern of the patterned layer on the surface of the substrate was visible. In particular, in Examples 1 to 4 and 7, the thickness of the transparent resin layer and the transparent substrate sheet was thinner compared to Example 5, and the pattern was more clearly visible. In Example 6, there was no transparent resin layer, and the thickness of the transparent substrate sheet was thinner compared to Example 5, and the surface protective layer was also thinner (5 μm), and the pattern was more clearly visible. In Example 6, although the surface protective layer was thin, the formulation of the surface protective layer-forming composition made the surface protective layer hard, and it was found to exhibit high scratch resistance.

[0184] Example 8 A transparent film and decorative panel were prepared in the same manner as in Example 1, except that 3 parts by mass of a phosphate-based glass silver-supported compound (PG-711, manufactured by Koa Glass Co., Ltd.) was added as an antiviral agent to 100 parts by mass of an ionizing radiation-curable resin that forms the surface protective layer. The peak height ratio between surface protective layer A and B, and the peak height ratio between B and C were the same as in Example 1.

[0185] The transparent films prepared in Example 1 and Example 8 were used for the following evaluations.

[0186] [Antiviral Properties] <Evaluation Method> The transparent films prepared in Example 1 and Example 8 were subjected to antiviral performance tests in accordance with the antiviral test method (ISO 21702), and the antiviral activity value against influenza virus was calculated and evaluated based on the following evaluation criteria. The results are shown in Table 2. A + rating indicates that there are no problems in actual use. In Table 2, the antiviral agent (parts by mass) refers to the amount of antiviral agent used (parts by mass) per 100 parts by mass of ionizing radiation-curable resin. <Evaluation Criteria> +: Antiviral activity value was 2.0 or higher -: Antiviral activity value was less than 2.0

[0187] The results are shown in Table 2.

[0188]

[0189] Example 9 A transparent film and decorative panel were prepared in the same manner as in Example 1, except that the following resin composition was heat-melt extruded and laminated to form an 80 μm transparent resin layer as a transparent polypropylene resin (transparent random polypropylene resin). The peak height ratio of surface protective layers A to B and B to C were the same as in Example 1. (Resin composition) ・Transparent polypropylene resin: 100 parts by mass ・Ammonium polyphosphate (product name; EXOLIT AP423 (manufactured by Clariant Chemicals Co., Ltd.): 10 parts by mass

[0190] The transparent films prepared in Examples 1 and 9 were used for the following evaluations.

[0191] [Flame Retardancy Evaluation] The decorative panels produced in Example 1 and Example 9 were cut to a size of 9 cm x 30 cm to serve as test pieces. As shown in Figures 7 and 8, a rectangular metal stand 103 was placed on the base 102 of a commercially available household heater 101 (Zaigle Handsome SJ-100 (product name)), and the test piece 105 was placed inside a metal frame 104 installed on the stand. A test was then conducted to evaluate the resistance to flame spread under the conditions of a heater angle of 45° and heater output dial 4. Specifically, the test piece was preheated for 2 minutes using the above-mentioned household heater. Next, as shown in Figure 7, the heater-side end 106 in the longitudinal direction of the test piece was heated with a lighter 107 for 1 minute to ignite it, and the flame spread along the longitudinal direction of the test piece 105 as shown in Figure 8. The burning state was then visually observed, and the burning distance (L1) and burning duration were evaluated as follows. This evaluated the horizontal flammability (resistance to flame spread).

[0192] (Burning distance (L1)) The burning distance (L1) was measured by igniting the test piece and removing the lighter flame, then measuring the distance the flame spread from the initial ignition. This was evaluated according to the following evaluation criteria. A rating of + or higher indicates that there are no problems in actual use. ++: L1 is less than 5 cm +: L1 is 5 cm or more but less than 10 cm -: L1 is 10 cm or more

[0193] (Burning time) The burning time from initial ignition to self-extinguishing was measured after igniting the test piece and removing the lighter flame, and evaluated according to the following evaluation criteria. Note that a rating of + or higher is considered to be acceptable for actual use. +++: Burning time is less than 100 seconds, or no ignition occurs ++: Burning time is 100 seconds or more but less than 300 seconds +: Burning time is 300 seconds or more but less than 600 seconds -: Burning time is 600 seconds or more (does not self-extinguish after 600 seconds)

[0194] The results are shown in Table 3.

[0195]

[0196] 1: Transparent film 11: Transparent base sheet 12: Transparent resin layer 13: Surface protection layer 14: Base layer 2: Base material 21: Pattern layer 101. Household heater 102. Stand for household heater 103. Rectangular metal stand 104. Metal frame 105. Test piece 106. End of the test piece on the heater side in the longitudinal direction 107. Lighter L1. Burning distance

Claims

1. A transparent film having at least a transparent substrate layer and a surface protective layer, wherein the surface protective layer contains a cross-linked curable resin, and the infrared spectroscopic spectrum of the surface protective layer is 855 to 1325 cm⁻¹. －１ Let A be the height of the peak that appears, between 1650 and 1800 cm. －１ When the peak height appearing is B, the peak height ratio of A to B ((A / B) × 100 (%)) is between 105% and 400%, and in the infrared spectroscopic spectral measurement of the surface protective layer, at 3200 to 3500 cm⁻¹ －１ A transparent film characterized in that the peak height ratio ((B / C) × 100 (%)) of B and C, where C is the peak height appearing in the image, is between 1000% and 6000%.

2. The transparent film according to claim 1, wherein the peak height ratio of A to B is 110% or more and 300% or less, and the peak height ratio of B to C is 1300% or more and 5500% or less.

3. The transparent film according to claim 1, wherein the cross-linked curable resin includes an ionizing radiation curable resin.

4. The transparent film according to claim 3, wherein the ionizing radiation-curable resin includes an acrylic resin having (meth)acryloyl groups.

5. The transparent film according to claim 1, wherein the surface protective layer comprises at least one selected from the group consisting of antibacterial agents, antiviral agents, and allergen reducing agents.

6. The transparent film according to claim 1, wherein the transparent substrate layer includes a thermoplastic resin layer, and the thermoplastic resin layer contains at least one thermoplastic resin selected from the group consisting of olefin resin, vinyl chloride resin, polyester resin, polycarbonate resin, and polyacrylic resin.

7. The transparent film according to claim 1, wherein the transparent substrate layer comprises, in order from the side opposite to the surface protective layer, at least a transparent substrate sheet and a transparent resin layer.

8. The transparent film according to claim 1, wherein the transparent substrate layer has an adhesive layer on the side opposite to the surface protective layer.

9. A decorative panel having a transparent film according to any one of claims 1 to 8 on a substrate.

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