Laminated body for thermoforming and method for forming the laminated body

Abstract

The present invention provides a thermoforming laminate having good thermoforming properties and excellent chemical resistance and wear resistance. As a technical solution to the above technical problems, a thermoforming laminate can be provided, which comprises: (a) a substrate layer comprising a thermoplastic resin; (b) a hard coating layer which is a post-cured hard coating layer comprising an active energy ray-curable resin having a (meth)acryloyl group, the hard coating layer containing a polymerization inhibitor; and (c) a protective film, wherein the (a) substrate layer, the (b) hard coating layer, and the (c) protective film are laminated in the order described, and the polymerization inhibitor contains at least one of a quinone compound, a sulfur-containing compound, and a nitrogen-containing compound.

Description

Technical Field

[0001] The present invention relates to a laminate for thermoforming and a method for molding the laminate for thermoforming. Background Art

[0002] For molded products for home appliances and vehicles, plastic molded products have been coated so far, but due to the heavy environmental burden, a method of insert molding a decorative film that can be thermoformed is also used. In recent years, as the requirements for chemical resistance and scratch resistance increase, there is a great demand for thermoforming films with hard coatings. Thermoforming films with hard coatings are usually manufactured by applying a hard coating liquid on a substrate and then curing it with UV light.

[0003] Formability, chemical resistance, and scratch resistance are mutually exclusive. In other words, generally, when formability is improved, chemical resistance and scratch resistance are reduced, and when chemical resistance and scratch resistance are improved, formability is deteriorated. Therefore, in order to solve these problems, a post-curing type has been proposed in which forming is performed without curing after hard coating is applied, and curing is performed by UV irradiation or the like after forming.

[0004] In the post-curing type of hard coating for thermoforming, there are also hard coatings with a protective film attached to prevent scratches and foreign matter. If foreign matter is included in the molding process, it will cause a significant decrease in the yield rate. Therefore, it is desirable to mold the hard coating in a clean environment with the protective film attached.

[0005] However, in order to perform thermoforming, the substrate of the hard coat needs to be heated to a temperature higher than the Tg to soften it. In conventional post-curing hard coats, if heated with a protective film attached, curing occurs, which greatly impairs thermoformability.

[0006] Furthermore, in the conventional post-curing hard coating film, if thermoforming is performed with a protective film attached, the texture of the protective film is transferred, resulting in a deterioration in appearance.

[0007] For these reasons, in conventional hard coating films, the protective film is usually peeled off before molding.

[0008] As described above, it is not easy to obtain a molded product having excellent chemical resistance, scratch resistance, etc. by performing thermoforming without deteriorating the appearance while ensuring the thermoformability of the hard coating for thermoforming with a protective film.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application No. 2017-508828 Summary of the invention

[0012] Technical problem to be solved by the invention

[0013] The main technical problems to be solved by the present invention include providing a laminate for thermoforming having good thermoformability and excellent chemical resistance and wear resistance.

[0014] Technical solutions for solving technical problems

[0015] The present invention includes the following.

[0016] (1) A laminate for thermoforming, comprising: (a) a substrate layer comprising a thermoplastic resin; (b) a hard coating layer which is a post-cured hard coating layer comprising an active energy ray-curable resin having a (meth)acryloyl group, the hard coating layer containing an inhibitor; and (c) a protective film, wherein the (a) substrate layer, the (b) hard coating layer and the (c) protective film are stacked in the order described, and the inhibitor contains at least any one of a quinone compound, a sulfur-containing compound and a nitrogen-containing compound.

[0017] (2) A laminate for thermoforming as described in (1) above, wherein the polymerization inhibitor comprises a quinone compound selected from the group consisting of 2-hydroxynaphthoquinone, N-isopropyl-N′-phenyl-p-phenylenediamine, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl, phenothiazine and 2-mercaptobenzimidazole.

[0018] (3) The thermoforming laminate according to (2) above, wherein the polymerization inhibitor comprises a quinone compound selected from the group consisting of N-isopropyl-N′-phenyl-p-phenylenediamine, phenothiazine and 2,2,6,6-tetramethyl-4-oxopiperidine-1-oxyl.

[0019] (4) The thermoforming laminate according to any one of (1) to (3) above, wherein the hard coat layer contains 0.0001 to 5% by weight of the polymerization inhibitor.

[0020] (5) The laminate for thermoforming according to any one of (1) to (4) above, wherein the active energy ray-curable resin having a (meth)acryloyl group has a (meth)acrylate skeleton.

[0021] (6) The laminate for thermoforming according to any one of (1) to (5) above, wherein the hard coat layer contains nanoparticles.

[0022] (7) The laminate for thermoforming according to any one of (1) to (6) above, wherein the hard coat layer contains a leveling agent.

[0023] (8) A laminate for thermoforming as described in any one of (1) to (7) above, wherein before laminating to the hard coating layer, the surface free energy of the adhesion surface of the protective film as the surface on the hard coating side has a value of 30.0 (mN / m) or more, and the surface free energy value is calculated based on the OWRK method from the average contact angle of water and the average contact angle of diiodomethane.

[0024] (9) The laminate for thermoforming according to any one of (1) to (8) above, wherein the surface roughness Sa of the adhesion surface of the protective film has a value of 0.1 μm or less.

[0025] (10) The laminate for thermoforming according to any one of (1) to (9) above, wherein the hard coat layer is ultraviolet-curable.

[0026] (11) The laminate for thermoforming according to any one of (1) to (10) above, wherein the thermoplastic resin contains an aromatic polycarbonate.

[0027] (12) The thermoforming laminate according to the above (11), wherein the aromatic polycarbonate comprises bisphenol A type polycarbonate.

[0028] (13) The laminate for thermoforming according to any one of (1) to (12) above, wherein the substrate layer comprises at least two layers of an acrylic resin layer and an aromatic polycarbonate layer.

[0029] (14) A method for forming a thermoforming laminate, comprising a thermoforming step of heating the thermoforming laminate according to any one of (1) to (13) above while the laminate is provided with the protective film.

[0030] (15) A molded product obtained by molding the laminate for thermoforming according to any one of (1) to (13).

[0031] (16) An article obtained by irradiating the molded product according to (15) above with active energy rays.

[0032] Effects of the Invention

[0033] In the thermoforming laminate of the present invention, as described above, the curable hard coating layer laminated between the substrate layer and the protective film contains a polymerization inhibitor. With such a thermoforming laminate, even when thermoforming is performed in a state where the protective film is laminated, the curing of the hard coating layer can be reliably suppressed, achieving good processability, and also preventing fine foreign matter from being mixed into the hard coating layer, thereby obtaining a good surface appearance. Therefore, such a thermoforming laminate is particularly suitable for thermoforming processing in a state where the protective film is attached.

[0034] Furthermore, if the thermoforming laminate is cured and the protective film is removed after thermoforming into a predetermined shape, a resin film laminate having a hard coating layer having excellent surface chemical resistance and abrasion resistance can be obtained.

[0035] The thermoforming laminate of the present invention having such excellent characteristics is particularly suitable as a material for a resin film laminate used in applications such as mobile devices and automobile interior parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a cross-sectional view showing a specific example of a laminate for thermoforming. DETAILED DESCRIPTION

[0037] Hereinafter, the present invention will be described in detail. In addition, the present invention is not limited to the following embodiments, and any changes can be made within the scope of the invention.

[0038] [Laminate for thermoforming]

[0039] The laminate for thermoforming of the present invention comprises (a) a substrate layer comprising a thermoplastic resin, (b) a curable hard coating layer, and (c) a protective film, wherein these layers are laminated in the order of (a) substrate layer, (b) hard coating layer, and (c) protective film. That is, the laminate of the present invention includes a laminate having layers other than the above (a) to (c), in addition to a laminate having (a) substrate layer directly laminated on one surface of (b) hard coating layer and (c) protective film directly laminated on the other surface.

[0040] The structure of the laminate for thermoforming is, for example, Figure 1 As shown. Figure 1 In the illustrated laminate 10, the outermost protective film 12 is laminated on the hard coating layer 16. Therefore, the surface of the hard coating layer 16 on the protective film 12 side is protected by the protective film 12. The hard coating layer 16 is laminated on the surface of the PMMA layer side of a substrate layer having a polymethyl methacrylate layer (PMMA resin layer) 20 and a polycarbonate layer (PC resin layer) 22, for example.

[0041] Hereinafter, each layer of the thermoforming laminate will be described.

[0042] [Base material layer]

[0043] The base layer is preferably laminated so as to be in contact with the surface of the hard coat layer on the side opposite to the protective film. However, another layer may be disposed between the base layer and the hard coat layer.

[0044] The substrate layer contains a thermoplastic resin. The type of thermoplastic resin is not particularly limited, and various resins such as polycarbonate (PC) resin, acrylic resin such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), triacetyl cellulose (TAC), polyethylene naphthalate (PEN), polyimide (PI), cycloolefin copolymer (COC), norbornene-containing resin, polyether sulfone, cellophane, and aromatic polyamide can be used. Among these options, the thermoplastic resin of the substrate layer preferably contains at least polycarbonate resin. In addition, from the viewpoint of toughness and heat resistance, it is desirable to use aromatic polycarbonate.

[0045] The type of polycarbonate resin contained in the substrate layer is not particularly limited as long as it is a resin containing a -[O-R-OCO]- unit having a carbonate bond in the main chain of the molecule (R is an aliphatic group, an aromatic group, or a group containing both an aliphatic group and an aromatic group, and further a group having a linear structure or a branched structure). Preferably, it is a polycarbonate having a bisphenol skeleton, and particularly preferably a bisphenol A type polycarbonate having a bisphenol A skeleton or a bisphenol C type polycarbonate having a bisphenol C skeleton. As the polycarbonate resin, a mixture or copolymer of bisphenol A and bisphenol C can be used. By using a bisphenol C-based polycarbonate resin, such as a polycarbonate resin of only bisphenol C, a mixture or copolymer of bisphenol C and bisphenol A, the hardness of the substrate layer can be increased.

[0046] The viscosity average molecular weight of a thermoplastic resin such as a polycarbonate resin is preferably 15,000 to 40,000, more preferably 20,000 to 35,000, and even more preferably 22,500 to 25,000.

[0047] In addition, the substrate layer preferably includes an acrylic resin. The acrylic resin contained in the substrate layer is not particularly limited, and for example, homopolymers of various (meth) acrylic esters represented by polymethyl methacrylate (PMMA) and methyl methacrylate (MMA), or copolymers of PMMA, MMA and other one or more monomers, and mixtures of multiple of these resins can be cited. Among these, (meth) acrylic esters containing cyclic alkyl structures with low birefringence, low hygroscopicity and excellent heat resistance are preferred. As examples of the (meth) acrylic resins described above, there are ACRYPET (manufactured by Mitsubishi Rayon Co., Ltd.), DELPET (manufactured by Asahi Kasei Chemicals Co., Ltd.), and PARAPET (manufactured by KURARAY Co., Ltd.), but are not limited to these.

[0048] As the substrate layer, a multilayer product including the above-mentioned polycarbonate resin layer and the above-mentioned acrylic resin layer can also be used. Thus, for example, in a multilayer product including at least two layers of an acrylic resin layer and an aromatic polycarbonate layer, a hard coating layer is preferably provided on the acrylic resin side. By using a multilayer product including a polycarbonate resin and an acrylic resin, the surface hardness can be increased while maintaining the thermoformability of the substrate.

[0049] In addition, the substrate layer may contain additives as components other than the thermoplastic resin. For example, at least one additive selected from a heat stabilizer, an antioxidant, a flame retardant, a flame retardant aid, an ultraviolet absorber, a release agent, and a colorant. In addition, an antistatic agent, a fluorescent brightener, an antifogging agent, a fluidity improver, a plasticizer, a dispersant, an antibacterial agent, etc. may also be added to the substrate layer.

[0050] The substrate layer preferably contains 80% by mass or more of a thermoplastic resin, more preferably 90% by mass or more, and particularly preferably 95% by mass or more of a thermoplastic resin. In addition, the substrate layer preferably contains 80% by mass or more of a polycarbonate resin, more preferably 90% by mass or more, and particularly preferably 95% by mass or more of a polycarbonate resin in the thermoplastic resin.

[0051] In the base material layer, in the layer containing the acrylic resin as the main component, the acrylic resin is preferably contained in an amount of 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0052] The thickness of the substrate layer is not particularly limited, but is preferably 0.10 mm to 1.0 mm. The thickness of the substrate layer is, for example, 0.15 mm to 0.80 mm, 0.18 mm to 0.60 mm, or 0.25 mm to 0.40 mm.

[0053] Furthermore, when the base material layer has a plurality of layers, the thickness of each layer may be within the above range, or the thickness of the entire base material layer may be within the above range.

[0054] [Hard coating]

[0055] The hard coat layer contains a polymerization inhibitor and an active energy ray-curable resin. Thus, the energy ray-curable hard coat layer can be cured even without a curing agent. However, the hard coat layer may also contain a photopolymerization initiator and various additives for improving the function of the hard coat layer.

[0056] <Polymerization inhibitor>

[0057] The hard coating composition for forming the hard coating layer contains a polymerization inhibitor, which suppresses polymerization of the active energy ray-curable resin caused by light or heat, thereby improving storage stability.

[0058] As the polymerization inhibitor used in the hard coat layer of the laminate of the present invention, hydroxy aromatic compounds, quinone compounds, nitrogen-containing compounds, sulfur compounds, etc. are used as described later.

[0059] Examples of the hydroxyaromatics include hydroquinone, phenols such as p-methoxyphenol (4-methoxyphenol), cresol, tert-butylcatechol, di(tert-butyl)hydroxytoluene such as 3,5-di-tert-butyl-4-hydroxytoluene, 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 2,2′-methylenebis(4-ethyl-6-butylphenol), and 4,4′-thiobis(3-methyl-6-tert-butylphenol).

[0060] Examples of the quinone-based compound include benzoquinone, naphthoquinone, 2-tert-butyl-1,4-benzoquinone, and 2-hydroxynaphthoquinone.

[0061] As the nitrogen-containing compound, amine compounds and nitroso compounds are known. Examples of the amine compound include p-phenylenediamine, 4-aminodiphenylamine, N,N′-diphenyl-p-phenylenediamine, N-isopropyl-N′-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine, N,N′-bis-2-naphthyl-p-phenylenediamine, diphenylamine, N-phenyl-β-naphthylamine, 4,4′-dicumyl-diphenylamine, 4,4′-dioctyl-diphenylamine, and 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline.

[0062] Examples of the nitroso compound include N-nitrosodiphenylamine, N-nitrosophenylnaphthylamine, N-nitrosodinaphthylamine, p-nitrosophenol, nitrosobenzene, p-nitrosodiphenylamine, and α-nitroso-β-naphthol.

[0063] Examples of the nitrogen-containing compounds other than those mentioned above include nitroxides such as piperidine-1-oxy, pyrrolidine-1-oxy, 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxy, and 2,2,6,6-tetramethylpiperidin-1-oxy. These nitrogen-containing compounds function as radical scavengers.

[0064] Examples of the sulfur-based compound include phenothiazine, distearylthiodipropionate, and 2-mercaptobenzimidazole.

[0065] As other polymerization inhibitors, transition metal salts such as copper salt compounds and manganese salt compounds can be cited. Such compounds include, for example, copper salts such as dialkyldithiocarbamate (the alkyl group is any of methyl, ethyl, propyl, and butyl, and may be the same or different), copper acetate, copper salicylate, copper thiocyanate, copper nitrate, copper chloride, copper carbonate, copper hydroxide, and copper acrylate; manganese dialkyldithiocarbamate (the alkyl group is any of methyl, ethyl, propyl, and butyl, and may be the same or different), manganese diphenyldithiocarbamate, manganese formate, manganese acetate, manganese octoate, manganese naphthenate, manganese permanganate, and manganese salts of ethylenediaminetetraacetic acid.

[0066] Among these polymerization inhibitors, quinone compounds, nitrogen-containing compounds, and sulfur-containing compounds are preferably used. These polymerization inhibitors can function even in an oxygen-free environment, and thus can effectively inhibit polymerization and curing caused by heating when thermoforming is performed with a protective film attached.

[0067] Furthermore, as the polymerization inhibitor, phenothiazine, 2-hydroxynaphthoquinone, N-isopropyl-N′-phenyl-p-phenylenediamine, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl, 2-mercaptobenzimidazole and the like are preferred, and phenothiazine, N-isopropyl-N′-phenyl-p-phenylenediamine, 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl and the like are particularly preferably used.

[0068] Based on the total weight of the hard coating composition forming the hard coating, the amount of the polymerization inhibitor added is preferably 0.0001 to 5% by weight, more preferably 0.0003 to 1% by weight, more preferably 0.0005 to 0.5% by weight, and particularly preferably 0.001 to 0.1% by weight (10 to 1000 ppm by weight). If the polymerization inhibitor is added excessively, there is a concern that it will adversely affect the physical properties of the hard coating and become a cause of coloration. On the other hand, if the amount of the polymerization inhibitor added is small, it will solidify when the hard coating is heated, and it may be impossible to suppress the deterioration of thermoformability.

[0069] <Active energy ray curing resin>

[0070] As active energy ray-curable resins, any compound that retains active energy ray curability can be used. As active energy ray-curable compounds, (meth)acrylate compounds ((meth)acrylate polymers·(meth)acrylate resins) having a (meth)acryloyl group are preferably used. The (meth)acrylate compound having a (meth)acryloyl group preferably has a (meth)acrylate skeleton. As (meth)acrylate compounds, for example, epoxy (meth)acrylate, polyurethane (meth)acrylate, polyester (meth)acrylate, etc. can be used. These active energy ray-curable resins can be easily purchased from various companies.

[0071] ·Epoxy (meth)acrylate

[0072] Among the above-mentioned active energy ray-curable compounds, epoxy (meth)acrylates derived from epoxy compounds are preferred. An example of the synthesis of epoxy (meth)acrylates is shown in formula (1). Epoxy (meth)acrylates can be obtained by adding acrylic acid or methacrylic acid having an unsaturated bond to an epoxy compound.

[0073]

[0074] (In formula (1), R is an alkyl group having a total carbon number of 1 to 12 which may contain at least one substituent selected from epoxy, hydroxyl, acryloyl and methacryloyl groups, or hydrogen, and R' is a methyl group or hydrogen.)

[0075] Epoxy (meth)acrylate having a (meth)acrylate skeleton can be obtained by, for example, copolymerizing (meth)acrylic acid and (meth)acrylate glycidyl ether to synthesize an epoxy compound having a (meth)acrylate skeleton, and then adding acrylic acid, methacrylic acid, etc. to the epoxy compound.

[0076]

[0077] Examples of the epoxy (meth)acrylate used in the hard coating composition include those having a repeating unit represented by the following formula (I).

[0078]

[0079] In formula (I), m is an alkylene group having 1 to 4 carbon atoms or a single bond, n is an alkyl group having 1 to 4 carbon atoms or hydrogen, p is a single bond or an alkylene group having 1 or 2 carbon atoms, and q is an alkyl group having a total carbon number of 1 to 12, which may contain at least one substituent selected from the group consisting of an epoxy group, a hydroxyl group, an acryloyl group, and a methacryloyl group, or hydrogen.

[0080] The epoxy (meth)acrylate polymer more preferably contains the following repeating units, i.e., in the above formula (I), m is an alkylene group having 1 or 2 carbon atoms, n is an alkyl group having 1 or 2 carbon atoms, p is a single bond or a methylene group, and q is an alkyl group having a total carbon number of 1 to 6 or a hydrogen repeating unit which may contain at least one substituent selected from the group consisting of a glycidyl group, a hydroxyl group and an acryloyl group.

[0081] For example, in the above formula (I), m is a methylene group, n is a methyl group, p is a single bond, q is a methyl group, an alkyl group having 5 or less carbon atoms containing a glycidyl group (epoxy group), an alkyl group having 8 or less carbon atoms containing a hydroxyl group and an acryloyl group, etc.

[0082] Specific examples of the repeating unit contained in the epoxy (meth)acrylate polymer include repeating units represented by the following formula (II-a), formula (II-b), and formula (II-c).

[0083]

[0084] In the epoxy (meth) acrylate polymer, based on the total molar number of the repeating unit of the above formula (II-a), the repeating unit of the above formula (II-b) and the repeating unit of the above formula (II-c), the repeating unit of the above formula (II-a) is preferably 30 to 85 mol%, more preferably 40 to 80 mol%. Based on the above total molar number, the repeating unit of the above formula (II-b) is preferably 5 to 30 mol%, more preferably 10 to 25 mol%. In addition, based on the above total molar number, the repeating unit of the above formula (II-c) is preferably 10 to 40 mol%, more preferably 10 to 35 mol%.

[0085] The molar ratio of the repeating unit of the formula (II-a), the repeating unit of the formula (II-b), and the repeating unit of the formula (II-c) is preferably 4.5 to 5.5:1.5 to 2.5:2.5 to 3.5, for example, 5:2:3.

[0086] Polyurethane (meth)acrylate

[0087] As described above, the following urethane (meth)acrylates can also be used as the active energy ray-curable resin having a (meth)acryloyl group.

[0088] (Polyurethane acrylate having a molecular structure containing a ring skeleton)

[0089] As the polyurethane acrylate resin, a polyurethane acrylate having a molecular structure containing a cyclic skeleton is preferred. More specifically, as a specific example of a preferred polyurethane acrylate, a polymer of an isocyanate compound and an acrylate compound having a cyclic skeleton can be cited. In addition, the polyurethane acrylate resin having a molecular structure having a cyclic skeleton is preferably an active energy ray-curable type.

[0090] Isocyanate compounds

[0091] As the isocyanate compound, for example, an aromatic isocyanate which may have an alkyl substituent such as a methyl group can be used. The aromatic isocyanate is preferably an aromatic isocyanate having a total carbon number of 6 to 16, more preferably an aromatic isocyanate having a carbon number of 7 to 14, and particularly preferably an aromatic isocyanate having a carbon number of 8 to 12.

[0092] As the above-mentioned isocyanate compound, aromatic isocyanates are preferred, but aliphatic isocyanates, alicyclic isocyanates, and the like may also be used.

[0093] For example, preferred structural units of the urethane (meth)acrylate include toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, phenylene diisocyanate, lysine diisocyanate, lysine triisocyanate, naphthalene diisocyanate and other polyisocyanates, or trimer or tetramer compounds of these polyisocyanates, biuret type polyisocyanates, water-dispersible polyisocyanates (e.g., "AQUANATE 100", "AQUANATE 110", "AQUANATE 1110" and "AQUANATE 1110" manufactured by Nippon Polyurethane Industry Co., Ltd.) 200", "AQUANATE 210", etc.) or reaction products of these polyisocyanates with polyols, etc.

[0094] Among these isocyanate compounds, preferred specific examples include diphenylmethane diisocyanate, toluene diisocyanate, naphthalene diisocyanate, trimethylolpropane (TMP) adduct of toluene diisocyanate, isocyanate of toluene diisocyanate, TMP adduct of xylene diisocyanate, and dicyclohexylmethane diisocyanate (H12MDI) shown in the following formula, isophorone diisocyanate (IPDI), xylylene diisocyanate (XDI), etc.

[0095]

[0096] Acrylate compounds

[0097] Examples of the above-mentioned acrylate compound, i.e., the acrylate compound for forming polyurethane acrylate having a molecular structure preferably containing a cyclic skeleton, include pentaerythritol triacrylate (PETA), dipentaerythritol pentaacrylate (DPPA), and hydroxypropyl (meth)acrylate (hydroxypropyl acrylate: HPA).

[0098] Moreover, as an acrylate compound, the compound which has a (meth)acryloyloxy group and a hydroxyl group, for example, the monofunctional (meth)acrylic-type compound which has a hydroxyl group can also be used.

[0099] Examples of the monofunctional (meth)acrylic compound having a hydroxyl group include hydroxyl-containing mono(meth)acrylates {e.g., hydroxyalkyl (meth)acrylates [e.g., hydroxy C2-20 alkyl-(meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate, preferably hydroxy C2-12 alkyl-(meth)acrylate, and more preferably hydroxy C2-6 alkyl-(meth)acrylate], polyalkylene glycol mono(meth)acrylates [e.g., poly C2-4 alkylene glycol mono(meth)acrylates such as diethylene glycol mono(meth)acrylate and polyethylene glycol mono(meth)acrylate], and hydroxyalkyl (meth)acrylates having three or more hydroxyl groups. Mono(meth)acrylates of polyols [e.g., mono(meth)acrylates of alkyl polyols such as glycerol mono(meth)acrylate and trimethylolpropane mono(meth)acrylate, mono(meth)acrylates of polymers of alkyl polyols such as diglycerol mono(meth)acrylate, etc.], N-hydroxyalkyl(meth)acrylamides (e.g., N-hydroxymethyl(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, etc.), adducts formed by adding lactones (e.g., C4-10 lactones such as ε-caprolactone) to the hydroxyl groups of these compounds (e.g., hydroxyalkyl(meth)acrylates) (e.g., adducts formed by adding about 1 to 5 mol of lactone), etc.

[0100] Moreover, these (meth)acrylic compounds can also be used individually or in combination of 2 or more types.

[0101] As a preferred specific example of the compound for forming a (meth)acryloyloxy group, 2-hydroxy-3-phenoxypropyl acrylate is mentioned.

[0102] Among the above-mentioned acrylate compounds, particularly preferred specific examples include pentaerythritol triacrylate (PETA), dipentaerythritol pentaacrylate (DPPA), and hydroxypropyl (meth)acrylate (hydroxypropyl acrylate: HPA).

[0103] Polymer of isocyanate compound and acrylate compound

[0104] Preferred specific examples of the polymer of the above-mentioned isocyanate compound and acrylate compound, i.e., urethane acrylate polymer, include polymers of xylylenediisocyanate (XDI) and pentaerythritol triacrylate (PETA), polymers of XDI and dipentaerythritol pentaacrylate (DPPA), polymers of dicyclohexylmethane diisocyanate (H12MDI) and PETA, polymers of isophorone diisocyanate (IPDI) and PETA, polymers of XDI and hydroxypropyl (meth)acrylate (HPA), and the like.

[0105] In addition, as polyurethane acrylates containing a cyclic skeleton, polymers containing a polyol compound as a structural unit in addition to the above-mentioned isocyanate compounds and acrylate compounds can also be cited. A polyol compound (polyol) is a compound having two or more hydroxyl groups in one molecule, and for example, the following compounds can be cited. That is, as examples of polyol compounds, ethylene glycol, propylene glycol, diethylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-butanediol, 3-methyl-1,2-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-methyl-4,5-pentanediol diols such as bisphenol A, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol, neopentyl glycol, hydroxypivalate, etc.; polylactone diols obtained by adding lactones such as ε-caprolactone to these diols; ester diols such as bis(hydroxyethyl) terephthalate; alkylene oxide adducts of bisphenol A, polyethylene glycol, polypropylene glycol, polybutylene glycol, etc. polyether diols; α-olefin epoxides such as propylene oxide and butylene oxide, CARDURA Monoepoxy compounds such as E10 [manufactured by Shell Chemical Company, trade name, glycidyl ester of synthetic highly branched saturated fatty acid]; trivalent or higher alcohols such as glycerol, trimethylolpropane, trimethylolethane, diglycerol, triglycerol, 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, sorbitol, and mannitol; polylactone polyols obtained by adding lactones such as ε-caprolactone to these trivalent or higher alcohols; alicyclic polyols such as 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, hydrogenated bisphenol A, and hydrogenated bisphenol F, etc.

[0106] For example, as the polyol compound, there can be mentioned urethane acrylate containing tricyclodidecane dimethanol (TCDDM) represented by the following formula as a structural unit.

[0107]

[0108] Preferred specific examples of the above-mentioned urethane acrylate polymer include tricyclodiecanedimethanol (TCDDM), a polymer of IPDI and PETA, a polymer of TCDDM, H12MDI and PETA, a polymer containing DPPA as a structural unit as a substitute for PETA in these polymers or together with PETA, a polymer of xylylenediisocyanate (XDI) and hydroxypropyl (meth)acrylate (HPA), and the like.

[0109] (Polyurethane acrylate containing specified structural units)

[0110] As preferred specific examples of the urethane acrylate resin, there can be mentioned those containing a structural unit derived from isocyanate and a structural unit derived from a compound having a (meth)acryloyloxy group and a hydroxyl group, as shown below.

[0111] Preferred structural units of the above-mentioned urethane (meth)acrylate include the following.

[0112] Isocyanate compounds

[0113] As the isocyanate compound forming the above-mentioned structural unit, for example, an aromatic isocyanate which may have an alkyl substituent such as a methyl group can be used. The aromatic isocyanate is preferably an aromatic isocyanate having a total carbon number of 6 to 16, more preferably an aromatic isocyanate having a carbon number of 7 to 14, and particularly preferably an aromatic isocyanate having a carbon number of 8 to 12.

[0114] As the above-mentioned isocyanate, isocyanate with a cyclic skeleton is preferred. Therefore, as preferred specific examples of the above-mentioned isocyanate, although aromatic isocyanate and alicyclic isocyanate (alicyclic isocyanate) can be listed, aliphatic isocyanate (non-cyclic aliphatic isocyanate) not having a cyclic skeleton can also be used.

[0115] For example, preferred compounds for forming the structural unit of the polyurethane (meth)acrylate include toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, phenylene diisocyanate, lysine diisocyanate, lysine triisocyanate, naphthalene diisocyanate and other polyisocyanates, or trimer or tetramer compounds of these polyisocyanates, biuret type polyisocyanates, water-dispersible polyisocyanates (e.g., "AQUANATE 100", "AQUANATE 110", "AQUANATE 1110" and "AQUANATE 1110" manufactured by Nippon Polyurethane Industry Co., Ltd.) 200", "AQUANATE 210", etc.) or reaction products of these polyisocyanates with polyols, etc.

[0116] Among these isocyanates, diphenylmethane diisocyanate, toluene diisocyanate, naphthalene diisocyanate, trimethylolpropane (TMP) adduct of toluene diisocyanate, isocyanate of toluene diisocyanate, TMP adduct of xylene diisocyanate, and the like are preferred. Compounds having a (meth)acryloyloxy group and a hydroxyl group

[0117] Preferred specific examples of the compound having a (meth)acryloyloxy group and a hydroxyl group for forming the above-mentioned structural unit include monofunctional (meth)acrylic compounds having a hydroxyl group.

[0118] Examples of the monofunctional (meth)acrylic compound having a hydroxyl group include hydroxyl-containing mono(meth)acrylates {e.g., hydroxyalkyl (meth)acrylates [e.g., hydroxy C2-20 alkyl-(meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate, preferably hydroxy C2-12 alkyl-(meth)acrylate, and more preferably hydroxy C2-6 alkyl-(meth)acrylate], polyalkylene glycol mono(meth)acrylates [e.g., poly C2-4 alkylene glycol mono(meth)acrylates such as diethylene glycol mono(meth)acrylate and polyethylene glycol mono(meth)acrylate], polyalkylene glycol mono(meth)acrylates having three or more hydroxyl groups; Mono(meth)acrylates of polyols containing alkyl groups [e.g., mono(meth)acrylates of alkyl polyols such as glycerol mono(meth)acrylate and trimethylolpropane mono(meth)acrylate, mono(meth)acrylates of polymers of alkyl polyols such as diglycerol mono(meth)acrylate, etc.], N-hydroxyalkyl(meth)acrylamides (e.g., N-hydroxymethyl(meth)acrylamides, N-(2-hydroxyethyl)(meth)acrylamide, etc.), adducts formed by adding lactones (e.g., C4-10 lactones such as ε-caprolactone) to the hydroxyl groups of these compounds (e.g., hydroxyalkyl(meth)acrylates) (e.g., adducts formed by adding about 1 to 5 mol of lactone), etc.

[0119] Moreover, these (meth)acrylic compounds can also be used individually or in combination of 2 or more types.

[0120] As a preferred specific example of the compound for forming an alkyl group (A3 described later) containing a (meth)acryloyloxy group, 2-hydroxy-3-phenoxypropyl acrylate can be mentioned.

[0121] Examples of the urethane (meth)acrylate containing the above-specified structural unit include polymers containing a polyol compound as a structural unit in addition to an isocyanate compound and a compound having a (meth)acryloyloxy group and a hydroxyl group.

[0122] A polyol compound (polyol) is a compound having two or more hydroxyl groups in one molecule, and examples thereof include the following compounds. That is, examples of polyol compounds include ethylene glycol, propylene glycol, diethylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-butanediol, 3-methyl-1,2-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-methyl-4,5-pentanediol. diols such as bisphenol A, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol, neopentyl glycol, hydroxypivalate, etc.; polylactone diols obtained by adding lactones such as ε-caprolactone to these diols; ester diols such as bis(hydroxyethyl) terephthalate; alkylene oxide adducts of bisphenol A, polyethylene glycol, polypropylene glycol, polybutylene glycol, etc. polyether diols; α-olefin epoxides such as propylene oxide and butylene oxide, CARDURA Monoepoxy compounds such as E10 [manufactured by Shell Chemical Company, trade name, glycidyl ester of synthetic highly branched saturated fatty acid]; trivalent or higher alcohols such as glycerol, trimethylolpropane, trimethylolethane, diglycerol, triglycerol, 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, sorbitol, and mannitol; polylactone polyols obtained by adding lactones such as ε-caprolactone to these trivalent or higher alcohols; alicyclic polyols such as 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, hydrogenated bisphenol A, and hydrogenated bisphenol F, etc.

[0123] The urethane (meth)acrylate containing a polyol compound as a structural unit in addition to an isocyanate compound and a compound having a (meth)acryloyloxy group and a hydroxyl group preferably contains at least a component represented by the following formula (i).

[0124] (A3)-O(OC)HN-A2-HN(OC)-O-A1-O-(CO)NH-A2-NH-(CO)O-(A3)···(i)

[0125] (In formula (i),

[0126] A1 is an alkylene group derived from the above-mentioned polyol compound,

[0127] A2 is independently an alkylene group derived from the above isocyanate compound,

[0128] A3 are each independently an alkyl group derived from the above-mentioned compound having a (meth)acryloyloxy group and a hydroxyl group.)

[0129] Preferred specific examples of the urethane (meth)acrylate contained in the resin material include the following compounds containing structural units derived from ethylene glycol, pentaerythritol triacrylate and isophorone diisocyanate. In the following formula, the value of n is 0-10, preferably 1-5, and more preferably 1-3.

[0130]

[0131] In the polyurethane acrylate resin, the ratio of the compound having a (meth)acryloyloxy group and a hydroxyl group or the structural unit derived from such a compound to the isocyanate or the structural unit derived from the isocyanate is preferably 99:1 to 30:70 (weight ratio), more preferably 97:3 to 60:40, and even more preferably 95:5 to 80:20.

[0132] (Urethane acrylate containing acrylate)

[0133] Preferred specific examples of the urethane acrylate resin include resins containing urethane acrylate and acrylate, and more preferred specific examples of such urethane acrylate resins include resins containing a mixture of hexafunctional urethane acrylate and bifunctional acrylate.

[0134] (6-functional) polyurethane acrylate

[0135] As described above, the urethane acrylate resin preferably contains urethane acrylate, particularly hexafunctional urethane acrylate.

[0136] Preferred compounds of the hexafunctional urethane acrylate include compounds represented by the following formula, i.e., polymers of dicyclohexylmethane diisocyanate (H12MDI) and pentaerythritol triacrylate (PETA), polymers of isophorone diisocyanate (IPDI) and PETA, etc. Specific examples of preferred products of these hexafunctional urethane acrylates include UN-3320HC (polymer of H12MDI and PETA: manufactured by Negami Industries Co., Ltd.), CN-968 (polymer of IPDI and PETA: manufactured by Sartomer Japan Co., Ltd.), and CN-975 (manufactured by Sartomer Japan Co., Ltd.).

[0137]

[0138] (Meth)acrylate (bifunctional (meth)acrylate, etc.)

[0139] As described above, the (meth)acrylate preferably included in the urethane acrylate resin is preferably a compound having 4 to 20 carbon atoms, which contains at least one (meth)acryloyloxy group and at least one vinyl ether group and may have a substituent. The number of carbon atoms of the (meth)acrylate is preferably 6 to 18, more preferably 8 to 16. Examples of the substituent of the (meth)acrylate include an alkyl group and the like.

[0140] Moreover, as a (meth)acrylate, a bifunctional one is preferable.

[0141] As the (meth)acrylate, for example, 2-(2-vinyloxyethoxy)ethyl (meth)acrylate [2-(2-vinyloxyethoxy)ethyl acrylate: VEEA] of the following formula can be preferably used.

[0142]

[0143] (In the above formula, R is hydrogen or methyl.)

[0144] In the urethane acrylate resin, the ratio of urethane acrylate to (meth)acrylate is preferably 99:1 to 30:70 (weight ratio), more preferably 97:3 to 60:40, and even more preferably 95:5 to 80:20.

[0145] (Fluorinated polyurethane acrylate)

[0146] As the (meth)acrylate polymer, fluorine-containing urethane acrylate may also be used. The fluorine-containing urethane acrylate preferably contains at least a component represented by the following formula (ii).

[0147] (A3)-O(OC)HN-A2-HN(OC)-O-A1-O-(CO)NH-A2-NH-(CO)O-(A3)···(ii)

[0148] In the above formula (ii), A1 is preferably an alkylene group which may have a substituent and is derived from a fluorinated diol having a total carbon number of 8 or less, and the total carbon number is preferably 6 or less, for example 4. Examples of the substituent contained in the alkylene group of A1 include an alkyl group and the like.

[0149] In the above formula (ii), A2 is independently an alkylene group derived from an aliphatic or alicyclic isocyanate which may have a substituent and has a total carbon number of 4 to 20. The carbon number of A2 is preferably 6 to 16, more preferably 8 to 12. Examples of the substituent of the alkylene group of A2 include an alkyl group and the like.

[0150] As the alicyclic isocyanate forming A2, for example, isophorone diisocyanate of the following formula can be used.

[0151]

[0152] In the above formula (ii), A3 is independently an alkyl group having a total carbon number of 4 to 30 which contains at least one (meth)acryloyloxy group and may have a substituent. The total carbon number of A3 is preferably 6 to 20, more preferably 8 to 16. As a substituent of the alkyl group of A3, a branched alkyl group can be cited. A3 preferably contains at least 2 (meth)acryloyloxy groups, for example, 3 (meth)acryloyloxy groups.

[0153] In addition, as the compound forming A3, for example, pentaerythritol triacrylate of the following formula can be used.

[0154]

[0155] As the fluorine-containing urethane acrylate, those composed of the above-mentioned compounds are preferred. The fluorine-containing urethane acrylate includes, for example, a compound represented by the following formula (IV).

[0156]

[0157] ·Polyester (meth)acrylate

[0158] As the (meth)acrylate compound having a (meth)acryloyl group, the above-mentioned polyester (meth)acrylate can also be used.

[0159] As polyester (meth) acrylate, there can be mentioned polymers (resins) obtained by dehydration condensation reaction of (meth) acrylic acid, polycarboxylic acid (anhydride) and polyol. As polycarboxylic acid (anhydride) used in such dehydration condensation reaction, there can be mentioned succinic acid (anhydride), adipic acid, maleic acid (anhydride), itaconic acid (anhydride), trimellitic acid (anhydride), pyromellitic acid (anhydride), hexahydrophthalic acid (anhydride), phthalic acid (anhydride), isophthalic acid (anhydride), terephthalic acid (anhydride), etc. In addition, as polyol used in dehydration condensation reaction, there can be mentioned 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, dimethylolheptane, dimethylolpropionic acid, dimethylolbutyric acid, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, etc.

[0160] Specific examples of the polyester (meth)acrylate include ARONIX M-6100, ARONIX M-7100, ARONIX M-8030, ARONIX M-8060, ARONIX M-8530, and ARONIX M-8050 (these are trade names of polyester (meth)acrylate oligomers manufactured by Toagosei Co., Ltd.), Laromer PE44F, Laromer LR8907, Laromer PE55F, Laromer PE46T, and Laromer LR8800 (these are trade names of polyester (meth)acrylate oligomers manufactured by BASF), Ebecryl 80, Ebecryl 657, Ebecryl 800, Ebecryl 450, Ebecryl 1830, and Ebecryl 584 (these are trade names of polyester (meth)acrylate oligomers manufactured by Daicel UCB Corporation), and PHOTOMER RCC13-429, PHOTOMER 5018 (these are trade names of polyester (meth)acrylate oligomers manufactured by SAN NOPCO CORPORATION), and the like.

[0161] The (meth)acrylate polymer as the active energy ray-curable resin preferably has a (meth)acrylic acid equivalent of 200 to 500 g / eq. The (meth)acrylic acid equivalent of the (meth)acryloyl polymer is preferably 220 to 450 g / eq, more preferably 250 to 400 g / eq.

[0162] The (meth)acrylate polymer as the active energy ray-curable resin preferably has a weight average molecular weight of 5,000 to 200,000. The weight average molecular weight of the (meth)acrylate polymer is preferably 10,000 to 150,000, more preferably 15,000 to 100,000, and even more preferably 20,000 to 50,000.

[0163] The value of the weight average molecular weight can be measured based on the description in paragraphs 0061 to 0064 of JP-A-2007-179018. The details of the measurement method are as follows.

[0164] [Table 1]

[0165] Determination conditions of weight average molecular weight

[0166] Device "Aliance" manufactured by Waters Corporation Chromatographic columns Showa Denko "Shodex K-805L" (2 pieces) Detector UV detector: 254nm Eluent Chloroform

[0167] That is, first, a calibration curve showing the relationship between the dissolution time and the molecular weight of polycarbonate is prepared using a universal calibration method using polystyrene as a standard polymer. Thereafter, the dissolution curve (chromatogram) of polycarbonate is measured under the same conditions as in the case of the calibration curve. Further, the weight average molecular weight (Mw) is calculated from the dissolution time (molecular weight) of polycarbonate and the peak area (number of molecules) of the dissolution time. The weight average molecular weight is represented by the following formula (A), where Ni represents the number of molecules having a molecular weight Mi.

[0168] Mw=Σ(NiMi 2 ) / Σ(NiMi)····(A)

[0169] In addition, in this specification, (meth)acrylic acid includes acrylic acid and methacrylic acid.

[0170] As described above, for a hard coating composition containing a (meth)acrylate polymer having a (meth)acrylic acid equivalent and a weight average molecular weight within a specified range, the non-stick (tack-free) property before curing and the scratch resistance after curing are good, and the curing and polymerization reaction can also be easily carried out. That is, in the hard coating composition, by using a (meth)acrylate compound (polymer) having a (meth)acryloyl group, the non-stick (anti-adhesion) property can be improved, and the appearance can be suppressed from deteriorating even when thermoforming is performed with a protective film attached. This is because the protective film can be easily peeled off from the laminate after thermoforming. In addition, such a polymer (meth)acrylate compound having a (meth)acryloyl group is sold commercially and can be easily obtained. For example, it can be obtained from Dainippon Ink, Kyoeisha Chemical, DSP Gokyo Food & Chemical, etc.

[0171] Other active energy ray-curable resins

[0172] As the active energy ray-curable resin, (meth)acrylate compounds ((meth)acrylate polymers·resins) other than those described above, for example, (meth)acrylate compounds containing no (meth)acryloyl group or no (meth)acrylate skeleton, etc. may be used.

[0173] Furthermore, as the active energy ray-curable resin, resins other than (meth)acrylate compounds, for example, epoxy compounds, oxetane compounds, etc. can also be used.

[0174] In addition, a single or multiple types of active energy ray-curable resins may be used in the hard coating composition. The content of the active energy ray-curable resin in the hard coating composition is preferably 40% by weight or more, more preferably 60% by weight or more, and even more preferably 80% by weight or more, based on the total weight of the hard coating composition.

[0175] (Multifunctional acrylate compound)

[0176] For example, a pentaerythritol-based multifunctional acrylate compound may be added to the (meth)acrylate compound. As a multifunctional acrylate compound having a plurality of acrylate groups, preferably 3 or more acrylate groups, for example, pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate, and pentaerythritol triacrylate, which are represented by the following formulas (3) and (4), respectively, can be used.

[0177]

[0178]

[0179] Based on the total weight of the multifunctional acrylate compound and the (meth)acrylate compound, the multifunctional acrylate compound is preferably contained in an amount of 70% by weight or less, more preferably 50% by weight or less, and even more preferably 30% by weight or less. In this way, the multifunctional acrylate compound is added to the hard coating composition to react with the acryloyl group, glycidyl group (epoxy group), hydroxyl group, etc. contained in the side chain of the (meth)acrylate polymer, thereby forming a hard coating layer with higher scratch resistance.

[0180] (Nanoparticles)

[0181] In order to give the hard coating composition scratch resistance and hardness, nanoparticles can be added. The nanoparticles can be inorganic nanoparticles or organic nanoparticles, preferably inorganic nanoparticles. For example, metal oxide nanoparticles such as nano silicon dioxide, nano aluminum oxide, nano titanium dioxide, and nano zirconium dioxide can be used. In addition, nano diamonds can also be used.

[0182] As the inorganic nanoparticles contained in the hard coating composition, preferably silicon dioxide particles are contained. In addition, the nanoparticles contained in the hard coating are preferably treated with a surface treatment agent. Through the surface treatment, the inorganic nanoparticles can be dispersed in a stable state in the hard coating composition, particularly in the (meth)acrylate resin ((meth)acrylate polymer).

[0183] As a surface treatment agent for nanoparticles such as inorganic nanoparticles, a compound having: a substituent capable of bonding to the surface of the nanoparticles; and a substituent having high compatibility with the components of the hard coating composition in which the nanoparticles are dispersed, particularly a (meth)acryl polymer, can be suitably used. For example, a silane compound, an alcohol, an amine, a carboxylic acid, a sulfonic acid, a phosphonic acid, etc. can be used as a surface treatment agent.

[0184] The inorganic nanoparticles preferably have copolymerizable groups on the surface. The copolymerizable groups can be introduced by surface treatment of the inorganic nanoparticles, and specific examples of the copolymerizable groups include vinyl groups, meth(acrylic acid) groups, and radical polymerizable groups.

[0185] The average particle size of the nanoparticles is preferably 5 to 500 nm, more preferably 10 to 300 nm, and even more preferably 20 to 100 nm. The average particle size of the nanoparticles can be measured by, for example, a particle size measurement method using a dynamic light scattering method using a Zetasizer NanoZS from Malvern Panalytical.

[0186] The hard coating composition preferably contains 20 to 80 wt % of nanoparticles, such as inorganic nanoparticles, based on the total weight of the hard coating composition, more preferably 30 to 70 wt % of inorganic nanoparticles, and even more preferably 40 to 60 wt % of inorganic nanoparticles.

[0187] (Leveling agent)

[0188] In order to give the hard coating composition leveling properties, antifouling properties, and abrasion resistance, a silicone compound can be added as a leveling agent. Silicone compounds can use compounds having polyalkylsiloxane bonds. Although these compounds can also be synthetic products, commercial products can also be easily obtained. For example, the KP series of Shin-Etsu Silicone Co., Ltd., the BYK series of BYK-CHEMIE JAPAN Co., Ltd., and the TEGO Glide series of EVONIK Co., Ltd. can be used.

[0189] In order to give the hard coating composition leveling, antifouling and wear resistance, a fluorine compound as a leveling agent can be added. Fluorine compounds can use compounds with perfluoropolyether bonds. Although these compounds can also use synthetic products, commercial products can also be easily obtained. For example, DIC's MEGAFACE RS series, Shin-Etsu Chemical Co., Ltd.'s KY series, Daikin Industries, Ltd.'s OPTOOL series, etc. can be used.

[0190] The hard coating composition preferably contains 0.1 wt % to 10 wt % of a leveling agent based on the total weight of the hard coating composition. The content of the leveling agent in the hard coating composition is more preferably 0.5 wt % to 7 wt %, and even more preferably 1 wt % to 5 wt %.

[0191] (Curing property of hard coating composition)

[0192] The hard coating composition preferably has energy ray curing or heat curing, more preferably has energy ray curing, and even more preferably has ultraviolet curing. Therefore, it is preferred that the hard coating composition further contains a photopolymerization initiator. As the photopolymerization initiator, IRGACURE 184 (1-hydroxy-cyclohexyl-phenyl-ketone), IRGACURE 1173 (2-hydroxy-2-methyl-1-phenyl-propane-1-ketone), IRGACURE TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), IRGACURE 819 (bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), EsacureONE (oligo(2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone), etc. can be used. Among these, IRGACURE TPO, etc. are preferred as photopolymerization initiators from the viewpoint of heat resistance.

[0193] The hard coating composition contains, for example, 1% to 6% by weight of a photopolymerization initiator based on the total weight of the hard coating composition. The content of the photopolymerization initiator in the hard coating composition is more preferably 2% to 5% by weight, and even more preferably 3% to 4% by weight.

[0194] (Other additives)

[0195] The hard coating composition may contain other additives, such as at least one additive selected from the group consisting of a heat stabilizer, an antioxidant, a flame retardant, a flame retardant aid, an ultraviolet absorber, a release agent, and a colorant. Antistatic agents, fluorescent brighteners, antifogging agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, etc. may also be added to the hard coating composition as long as the desired physical properties are not significantly impaired.

[0196] In the hard coating composition, the active energy ray-curable resin such as the (meth)acrylate polymer and the nanoparticles preferably contain 60% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more in total. Therefore, in the hard coating composition, the content of components other than the above two main components is preferably less than 40% by mass, more preferably less than 20% by mass, and particularly preferably less than 10% by mass.

[0197] The diluent solvent used in the preparation of the hard coating composition for forming a hard coating layer is used to adjust the viscosity and is not particularly limited as long as it is a non-polymerizable solvent. The diluent solvent can be used to easily apply the hard coating composition mainly on the transparent substrate.

[0198] Examples of the diluting solvent include toluene, xylene, ethyl acetate, propyl acetate, butyl acetate, methyl cellosolve, ethyl cellosolve, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, methanol, ethanol, isopropanol, butanol, diacetone alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, hexane, heptane, octane, decane, dodecane, propylene glycol monomethyl ether, and 3-methoxybutanol.

[0199] <Manufacturing of hard coating>

[0200] The hard coat layer is produced, for example, by coating a composition containing an active energy ray-curable resin such as the (meth)acrylate polymer, a polymerization inhibitor, etc. For example, the hard coat composition is produced by mixing components such as the (meth)acrylate polymer and stirring them with a disperser.

[0201] As a method for applying the hard coating composition on the surface of the substrate layer, a rod coater, a gravure coater, a die coater, dip coating, spray coating, etc. can be used. At this time, after applying the hard coating liquid (hard coating composition), it is dried at a specified temperature. The drying temperature is preferably 30 to 150°C, and more preferably 60 to 120°C. When it is below 30°C, there will be residual organic solvent, which is likely to affect the physical properties of the hard coating. In addition, when it is above 150°C, there is a possibility of deformation of the substrate.

[0202] The film thickness of the hard coat layer is preferably in the range of 1 μm to 10 μm, more preferably in the range of 2 μm to 7 μm. If it is less than 1 μm, the prescribed performance cannot be obtained, and if it exceeds 10 μm, there is a possibility that the adhesion and moldability may deteriorate.

[0203] <Properties of hard coating>

[0204] (i) Non-stickiness

[0205] The hard coating layer contained in the laminate of the present invention has excellent non-stickiness. Moreover, although it does not have adhesiveness like a common adhesive layer, a protective film can be easily attached to the hard coating layer with high non-stickiness. In a molding laminate in which such a hard coating layer is coated with a protective film, the hard coating layer in an uncured state can maintain a prescribed shape even if it contacts other substances such as the operator's hand, and can prevent a portion of the hard coating layer from adhering to the surface of the contacted substance. The molding laminate having such excellent characteristics can be easily processed to cure after being molded into a shape suitable for various uses. In addition, it is also easy to store or circulate the molding laminate in a state before curing in a state in which the prescribed shape is maintained.

[0206] On the other hand, a resin composition with poor non-adhesiveness needs to be cured before being molded into a shape suitable for various uses, and therefore it is considered that there is a tendency for moldability to be poor.

[0207] (ii) Glossiness (appearance) after protection peeling

[0208] The hard coating layer is processed into a film shape in an uncured state, and when the protective film is laminated and peeled off, the unevenness on the film surface can be suppressed, and a good gloss can be maintained. It was confirmed that the hard coating layer contained in the laminate of the present invention can keep the surface smooth after the protective film is peeled off and maintain a good gloss in such an evaluation test.

[0209] (iii) Formability (gas pressure formability)

[0210] The hard coating layer of the molding laminate of the present invention is also excellent in moldability in an uncured state. The moldability of the hard coating composition is evaluated, for example, in the following manner. That is, after applying the hard coating composition on the surface of the substrate layer and drying it, the obtained laminate is placed on a mold having a convex portion and heated to perform air pressure moldability. At this time, the evaluation is performed based on whether the sheet-like hard coating composition follows the convex portion and stretches appropriately, and whether cracks are generated.

[0211] Although details are omitted, in this evaluation test, it was confirmed that the hard coating layer follows the convex portions without generating cracks during gas pressure formability and can be stretched.

[0212] (iv) Scratch resistance

[0213] In order to evaluate the test, when the hard coating is cured under the state of removing the protective film, high scratch resistance can be achieved. As shown in the details described later, it is confirmed that when the molding laminate with the hard coating is cured, the scratch resistance of the hard coating surface is also excellent than that of the cured PMMA resin (polymethyl methacrylate resin) and lens resin.

[0214] (v) Hardness

[0215] For evaluation tests, the hard coating layer cured with the protective film removed has high hardness. Specifically, it can achieve a pencil hardness of B or higher in the evaluation method of JIS K 5600-5-4: 1999. The surface of the hard coating layer after curing preferably achieves a pencil hardness of F or higher, particularly preferably 2H or higher.

[0216] (vi) Adhesion

[0217] Furthermore, the hard coating composition after curing was also excellent in adhesion. Specifically, a hard coating composition having an evaluation result of 0 determined by the evaluation method of JIS K 5600-5-6 was obtained.

[0218] Furthermore, after attaching the protective film to the hard coating layer formed of the (meth)acrylate polymer, a pressure of 30 kg / m was applied from above the mask at a temperature of 23 ± 2°C and a relative humidity of 50 ± 5%.2 The pressure is such that after 24 hours, the Sa value of the hard coating surface after the mask is peeled off is preferably 0.0300 μm or less, more preferably 0.0200 μm or less, and even more preferably 0.0150 μm or less.

[0219] The conditions for peeling the protective film from the surface of the hard coat layer were as follows: the peeling angle, that is, the angle between the mask film and the hard coat surface during peeling, was 90 degrees, and the peeling speed was 600 mm / min.

[0220] [Protective film]

[0221] After the hard coating is dried, a protective film is attached to the hard coating surface to prevent the hard coating surface from being injured. In the protective film, the surface in contact with the hard coating surface is an adhesive surface with appropriate adhesion, which is attached to the surface of the hard coating surface. The protective film can be a single layer with only an adhesive layer, but preferably has a two-layer structure of a substrate and an adhesive layer. In the protective film of the two-layer structure, the adhesive surface of the adhesive layer is laminated on the hard coating layer in a manner that contacts the hard coating layer. The protective film can also be a multilayer structure that also contains layers other than the above-mentioned substrate and adhesive layer. In addition, the protective film can be a single-layer structure, and in the protective film of the single-layer structure, the adhesive surface as the side surface of the hard coating layer also has appropriate adhesion.

[0222] The base material of the protective film is preferably formed of a thermoplastic resin, and more preferably contains a polyolefin resin. As the polyolefin resin contained in the protective film, for example, polyethylene, polypropylene, etc. can be used, which can be a homopolymer or a copolymer. Polyethylene is preferred among the polyolefin resins.

[0223] As polyethylene, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), very low-density polyethylene (VLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE) and the like can be used, and low-density polyethylene is preferred.

[0224] As the polyolefin copolymer, a copolymer of ethylene or propylene and a monomer copolymerizable with these can be used. Examples of the monomer copolymerizable with ethylene or propylene include α-olefins, styrenes, dienes, cyclic compounds, and oxygen atom-containing compounds.

[0225] As the above-mentioned α-olefins, 1-butene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. can be listed. As the above-mentioned styrenes, styrene, 4-methylstyrene, 4-dimethylaminostyrene, etc. can be listed. As the above-mentioned dienes, 1,3-butadiene, 1,5-hexadiene, 1,4-hexadiene, 1,7-octadiene, etc. can be listed. As the above-mentioned cyclic compounds, norbornene, cyclopentene, etc. can be listed. As oxygen-containing compounds, hexenol, hexenoic acid, methyl octenoate, etc. can be listed. These copolymerizable monomers can be used alone, or two or more can be used simultaneously. In addition, it can also be a copolymer of ethylene and propylene.

[0226] The copolymer may be an alternating copolymer, a random copolymer or a block copolymer.

[0227] The polyolefin resin contained in the base material of the protective film may contain a small amount of modified polyolefin resin modified with a carboxyl group-containing monomer such as acrylic acid, maleic acid, methacrylic acid, maleic anhydride, fumaric acid, itaconic acid, etc. The modification can usually be performed by copolymerization or graft modification.

[0228] The substrate of the protective film preferably contains 80% by weight or more of a polyolefin resin, more preferably 90% by weight or more of a polyolefin resin, and even more preferably 95% by weight or more of a polyolefin resin, based on the total weight of the substrate.

[0229] The adhesive layer of the protective film is preferably formed of an elastomer or a thermoplastic resin. As the thermoplastic resin contained in the adhesive layer, polyolefin resins such as polypropylene and modified polyolefin can be cited. As the polyolefin resin contained in the protective film (mask), for example, polyethylene, polypropylene, etc. can be used, which can be a homopolymer or a copolymer. Polyethylene is preferred among the polyolefin resins.

[0230] The adhesive layer of the protective film preferably contains 80 wt % or more of an elastomer or thermoplastic resin, more preferably 90 wt % or more of an elastomer or thermoplastic resin, and even more preferably 95 wt % or more of an elastomer or thermoplastic resin, based on the total weight of the adhesive layer.

[0231] In the molding laminate, the thickness of the protective film is preferably 10 μm to 100 μm, more preferably 20 μm to 80 μm.

[0232] The adhesive surface of the protective film, that is, the adhesive surface in contact with the surface of the hard coating layer, preferably has a surface free energy of 30.0 (mN / m) or more in the state before being attached to the hard coating layer. The value of the surface free energy can be determined based on the θ / 2 method to measure the average contact angle of 1 μl of water and the average contact angle of 1 μl of diiodomethane (CH2I2) placed on the above-mentioned adhesive surface, and calculated from the values ​​of these average contact angles based on the OWRK method (Owens-Wendt-Rabel-Kaelble method). The value of the surface free energy of the above-mentioned adhesive surface is preferably 31.0 (mN / m) or more.

[0233] The average contact angle value of 1 μl of diiodomethane on the adhesive surface of the protective film in contact with the hard coat surface is preferably 64° or less, more preferably 60° or less, and even more preferably 58° or less.

[0234] The protective film having such an adhesive surface with high surface free energy or a small contact angle of a standing diiodomethane droplet can be said to have high wettability. When the surface of the hard coating layer is covered with a protective film with high wettability, fine irregularities are not generated on the surface of the hard coating layer, and the surface can be easily maintained smooth.

[0235] Furthermore, such a protective film can reliably protect the surface of the hard coating layer even when the hard coating layer is in an uncured and soft state, and thus the moldability of the hard coating layer can be easily improved.

[0236] In the protective film, the surface roughness Sa value (ISO 25178) of the adhesive surface for contacting the hard coating layer before being attached to the hard coating layer (unattached) is preferably 0.100 μm or less. The surface roughness Sa value of the adhesive surface of the protective film in the unattached state is more preferably 0.090 μm or less, more preferably 0.080 μm or less, and particularly preferably 0.070 μm or less.

[0237] The adhesive force of the adhesive surface of the protective film is preferably 5 (mN / 25 mm) or more and 5000 (mN / 25 mm) or less, and more preferably 9 (mN / 25 mm) or more and 3000 (mN / 25 mm) or less, to the surface of the PMMA (polymethyl methacrylate resin layer).

[0238] The laminated body used for thermoforming is manufactured as follows. First, materials such as resin composition are processed into layers (sheets) by existing methods to manufacture substrate layers. For example, there are methods utilizing extrusion molding and casting molding. As an example of extrusion molding, it is possible to cite a method in which pellets, flakes or powders of the resin composition are melted and mixed using an extruder, and then extruded from a T-die, etc., and the resulting semi-molten sheet is cooled while being clamped with a roller to solidify and form a sheet.

[0239] Next, the hard coating composition produced as described above is applied to the outer surface of the substrate layer having a single layer or multiple layers to form a hard coating layer.

[0240] The above-mentioned protective film was bonded to the surface of the hard coating layer side of the intermediate body of the base layer and the hard coating layer thus obtained to produce a laminate for thermoforming.

[0241] [Thermoforming of laminated body]

[0242] The laminate for thermoforming can be formed by any method as long as the film is heated and formed, for example, by heat forming into a desired shape by air pressure forming in which the substrate is heated and formed by air pressure, vacuum air pressure forming in which the substrate is formed under vacuum conditions, TOM forming, etc.

[0243] The molding temperature of the thermoforming laminate is mainly determined by the Tg (glass transition temperature) of the thermoplastic resin of the substrate layer. The molding temperature is a temperature higher than the Tg of the thermoplastic resin of the substrate layer by 0°C to 70°C, and more preferably 20 to 40°C. For example, in the case of a laminate containing a substrate layer obtained from ordinary bisphenol A polycarbonate, molding is most preferably performed in the range of 170 to 190°C.

[0244] The thermoforming laminate can suppress the polymerization reaction of the hard coating layer even when heated, so it can be molded in a state where the protective film is attached. That is, the molding method of the thermoforming laminate of the present invention includes a thermoforming step of heating the laminate in a state where the protective film is attached. By performing a series of operations in a state where the protective film is attached, not only the occurrence of scratches can be suppressed, but also the introduction of foreign matter can be suppressed.

[0245] [Manufacturing of molded products and articles]

[0246] As described above, if the protective film is removed from the laminated body thermoformed into a predetermined shape and cured, a molded product such as a cured film can be obtained. The surface of the hard coating side of the molded product such as the cured film thus manufactured has excellent properties. That is, on the surface of the hard coating side of the molded product, high pencil hardness, preferably pencil hardness of B or above based on JISK 5600-5-4:1999, high scratch resistance, and excellent adhesion, for example, adhesion of grade 0 in the evaluation result of JISK 5600-5-6 are all achieved.

[0247] Furthermore, the molded product thus obtained may be irradiated with active energy rays such as ultraviolet rays to produce a cured product.

[0248] Examples of articles of the above-mentioned molded product include resin film laminates used in mobile devices, automobile interior parts, and the like.

[0249] Example

[0250] The following examples are given to further illustrate the present invention. However, the present invention is not limited to the following examples, and can be implemented by any changes without departing from the scope of the present invention. Heat resistance test (heat resistance test):

[0251] The thermoforming laminate obtained in each of the examples described below was heated at 200°C for 2 minutes with a protective film attached. After peeling off the protective film, 1 ml of methyl ethyl ketone was dripped on the surface of the hard coating layer in contact with the protective film. After 1 minute, the appearance was confirmed. The molded body with improved chemical resistance was judged to be a molded body in which cross-linking occurred, that is, a polymerization reaction occurred in the hard coating composition. Thermoforming properties (including deep drawing properties and molding processability of right-angle shape forming properties):

[0252] The thermoforming laminate obtained in each example was cut into A4 size, and the sample obtained in the state of being affixed with a protective film was preheated at 190°C for about 40 seconds. Then, it was immediately subjected to air pressure forming with a mold having a right-angle protrusion with a deep drawing height by high-pressure air of 1.5 MPa. In addition, in the air pressure forming, a mold was used, that is, a right-angle shape with a longitudinal and lateral dimension of 30 mm, and a radius R of 1 mm and a height of 5 mm and 11 mm in the area connected to the right-angled part of the mold. By visual inspection, the laminate that did not whiten or crack at the end of the laminate after thermoforming, that is, the area along the mold bending, was evaluated as good, and the laminate that had either whitening or cracking was evaluated as poor.

[0253] Preparation Example 1

[0254] As a photopolymerizable compound, ART CURE RA-3602MI manufactured by Negami Industry Co., Ltd., which is a polymer acrylate type coating (acrylic polymer having a (meth)acryloyl group (reactive group) on the side chain of an acrylic skeleton), a photopolymerization initiator IRGACURE TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide; 3% by weight relative to the solid content) and a leveling agent BYK-UV3500 manufactured by BYK-CHEMIE (polyether-modified polydimethylsiloxane having an acrylic functional group; 1% by weight relative to the solid content) were added to obtain a mixed solution. The obtained mixture was diluted with propylene glycol monoethyl ether as a solvent so that the solid content concentration became 30%.

[0255] Example 1

[0256] To the photopolymerizable compound obtained in Preparation Example 1, 500 ppm by weight of phenothiazine was added in terms of solid content to prepare a hard coating composition. As the substrate layer, DF02U (Mitsubishi Gas Chemical Co., Ltd.: thickness 0.254 mm), a two-layer product of bisphenol A polycarbonate and PMMA, was used. The hard coating composition was applied to the surface of the PMMA side of the substrate layer using a rod coater in a film thickness of 3 μm, and after drying at 120°C for 5 minutes, a protective film (Sun A Chemical PAC-3-50THK) was attached to the surface of the obtained hard coating layer on the opposite side of the substrate. Then, the results of the thermoforming test performed by the above method were good in both the 5 mm height and the 11 mm height. In addition, the results of the heat reactivity and chemical resistance tests showed that no changes were observed on the surface of the hard coating layer, and the heat reactivity was good.

[0257] [Inhibitor 1] Phenothiazine

[0258]

[0259] Example 2

[0260] A laminate for thermoforming was obtained by the same method as in Example 1 except that phenothiazine was replaced with N-isopropyl-N′-phenyl-p-phenylenediamine. The results of the thermoforming test were good at both 5 mm height and 11 mm height. In addition, the results of the heat resistance test showed that no change was observed on the surface of the hard coating layer, indicating good heat resistance.

[0261] [Inhibitor 2] N-isopropyl-N'-phenyl-p-phenylenediamine

[0262]

[0263] Example 3

[0264] A laminate for thermoforming was obtained by the same method as in Example 1 except that phenothiazine was replaced with 2-hydroxynaphthoquinone. The result of the thermoforming test was good at a height of 5 mm. In addition, a heat resistance test was performed, but no change was observed, indicating good heat resistance.

[0265] [Inhibitor 3] 2-Hydroxynaphthoquinone

[0266]

[0267] Example 4

[0268] A laminate for thermoforming was obtained by the same method as in Example 1 except that phenothiazine was replaced with 2-mercaptobenzimidazole. The result of the thermoforming test was good at a height of 5 mm. In addition, a heat resistance test was performed, but no change was observed, indicating good heat resistance.

[0269] [Inhibitor 4] 2-Mercaptobenzimidazole

[0270]

[0271] Example 5

[0272] A laminate for thermoforming was obtained by the same method as in Example 1 except that phenothiazine was replaced with 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline. The result of the thermoforming test was good at a height of 5 mm. In addition, a heat resistance test was performed, but no change was observed, indicating good heat resistance.

[0273] [Polymerization Inhibitor 5] 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline

[0274]

[0275] Example 6

[0276] A laminate for thermoforming was obtained by the same method as in Example 1 except that phenothiazine was replaced with 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl. The result of the thermoforming test was good at a height of 5 mm. In addition, a heat resistance test was performed, but no change was observed, indicating good heat resistance.

[0277] [Polymerization Inhibitor 6] 2,2,6,6-Tetramethyl-4-oxopiperidin-1-oxy

[0278]

[0279] Example 7

[0280] Nanosilica particles (organic silica sol MEK-AC-2140Z manufactured by Nissan Chemical Industries) were mixed with the photopolymerizable compound obtained in Preparation Example 1 in a weight ratio of polymer: nanosilica particles = 80:20, and 500 ppm by weight of phenothiazine was added in terms of solid content to prepare a hard coating composition. The obtained composition was used to obtain a laminate for thermoforming by the same method as in Example 1. The results of the thermoforming test were good at both 5 mm height and 11 mm height. In addition, a heat resistance test was conducted, but no changes were observed, and the heat resistance was good.

[0281] Comparative Example 1

[0282] A laminate for thermoforming was obtained in the same manner as in Example 1 except that no phenothiazine was added. The thermoforming test showed that the laminate was defective at a height of 5 mm. The heat resistance test showed that the hard coating composition was crosslinked.

[0283] Comparative Example 2

[0284] A laminate for thermoforming was obtained in the same manner as in Example 1 except that phenothiazine was replaced with di(tert-butyl)hydroxytoluene. The thermoforming test showed that the laminate was poor at a height of 5 mm. The heat resistance test showed that the hard coating composition was crosslinked.

[0285] [Inhibitor 7] Di(tert-butyl)hydroxytoluene

[0286]

[0287] Comparative Example 3

[0288] A laminate for thermoforming was obtained in the same manner as in Example 1 except that phenothiazine was replaced with 4-methoxyphenol. The thermoforming test showed that the laminate was poor at a height of 5 mm. The heat resistance test showed that the hard coating composition was crosslinked.

[0289] [Inhibitor 8] 4-Methoxyphenol

[0290]

[0291] [Table 2]

[0292]

[0293] Embodiments 8 to 11

[0294] A hard coating composition was obtained in the same manner as in Example 1 except that the amount of phenothiazine added was changed under the conditions shown in Table 3 below. The results of the hot forming test carried out under the various conditions are shown in Table 3. Table 3 also includes the results of Example 1 described above.

[0295] [Table 3]

[0296]

[0297] Example 12

[0298] A laminate for thermoforming was obtained in the same manner as in Example 1 except that the substrate used was changed from DF-02U to bisphenol A polycarbonate monolayer film FE-2000 (manufactured by Mitsubishi Gas Chemical Co., Ltd.). The thermoforming test showed that both the 5 mm height and the 11 mm height were good.

[0299] Comparative Example 4

[0300] A laminate for thermoforming was obtained in the same manner as in Example 12 except that phenothiazine was not added. The thermoforming test showed that the laminate was defective at a height of 5 mm.

[0301] As described above, although some examples show poor results in the formability, the results of the heat resistance test are good in all examples. Thus, by using the above examples, even if the hard coating layer is thermoformed in a state where a protective film is laminated, the occurrence of polymerization reaction can be suppressed, and the desired shape can be formed without deteriorating the appearance. In addition, by curing the hard coating film of each example after thermoforming, a molded product with excellent chemical resistance, scratch resistance, etc. can be obtained.

[0302] Next, the hard coatings of the above-mentioned examples and comparative examples were cured using a Fusion H valve (Fusion UV Systems) at 90% output while blowing air at 1.8 m / min. The ultraviolet irradiation conditions were 1000 mJ / cm 2 .

[0303] [Evaluation of properties of laminated body]

[0304] The properties of the laminated body after being cured by ultraviolet (UV) irradiation and the laminated body in a state before the hard coat layer was cured (uncured laminated body) were evaluated as follows.

[0305] <Non-adhesiveness in the uncured state>

[0306] The non-stick properties of the uncured laminate were evaluated by finger touch evaluation.

[0307] <Glossiness after peeling off the uncured mask (appearance)>

[0308] A test piece having a base layer formed by laminating a polycarbonate resin and a PMMA resin was prepared, and a hard coating composition was applied to the PMMA resin side of the base layer of the test piece to form a hard coating layer with a thickness of 7 μm, and dried at 120° C. for 5 minutes.

[0309] Then, a polypropylene mask (protective film) with a thickness of 30 μm was attached to the surface of the uncured hard coat layer, and a pressure of 30 kg / m was applied from above the mask. 2 After 24 hours, the mask was peeled off and the surface roughness Sa (refer to ISO25178) of the hard coating surface was measured using a scanning white interference microscope VS1530 manufactured by Hitachi High-Technologies Corporation.

[0310] Examples and Comparative Examples having a surface roughness Sa value of less than 0.01 μm were evaluated as having good appearance.

[0311] <Abrasion resistance after curing>

[0312] On the surface of the hard coating after curing, at 100gf / cm 2 The scratch test was performed by moving #0000 steel wool back and forth 15 times under a pressure of . The absolute value (ΔH) of the haze change was calculated as the difference between the haze value measured in advance based on JIS K7136:2000 before the scratch test and the haze value measured based on JIS K 7136:2000 after the scratch test, and the evaluation was performed. The examples and comparative examples with a ΔH value of less than 3.0% were evaluated as having good scratch resistance.

[0313] <Chemical resistance after curing>

[0314] NEUTROGENA SPF100 was applied to the surface of the hard coat layer after curing, and after 1 hour at 80° C., the appearance was visually observed. Examples and Comparative Examples with no abnormality on the surface were evaluated as having good chemical resistance.

[0315] <Pencil hardness after curing>

[0316] The measurement was performed based on the conditions of JIS K 5600-5-4: 1999, and the evaluation was performed based on the number of the hardest pencil that did not cause scratches.

[0317] <Adhesion>

[0318] Evaluation was performed by the evaluation method of JIS K5600-5-6: 1999. Examples and Comparative Examples having an evaluation result of 0 were evaluated as having good adhesion.

[0319] Table 4 shows the measurement results of the properties of the films of the laminated bodies of the respective Examples and Comparative Examples.

[0320] [Table 4]

[0321]

[0322] As described above, it was confirmed that in the examples in which the active energy ray-curable hard coating composition containing a (meth)acrylate resin having a (meth)acryloyl group was cured, excellent properties were exhibited in terms of non-tackiness and appearance before curing, and scratch resistance, chemical resistance, pencil hardness and adhesion after curing.

[0323] Explanation of symbols

[0324] 10: laminate for molding; 12: protective film; 16: hard coating layer; 20: polymethyl methacrylate layer (substrate layer); 22: polycarbonate layer (substrate layer).

Claims

1. A laminate for thermoforming, characterized in that: have: (a) a substrate layer comprising a thermoplastic resin; (b) a hard coat layer which is a post-cured hard coat layer comprising an active energy ray-curable resin having a (meth)acryloyl group, the hard coat layer containing a polymerization inhibitor; and (c) a protective film, The (a) substrate layer, the (b) hard coating layer, and the (c) protective film are stacked in the order described, The polymerization inhibitor is selected from 2-hydroxynaphthoquinone, N-isopropyl-N'-phenyl-p-phenylenediamine, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl, phenothiazine and 2-mercaptobenzimidazole.

2. The laminate for thermoforming according to claim 1, characterized in that: The polymerization inhibitor is selected from N-isopropyl-N'-phenyl-p-phenylenediamine, phenothiazine and 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl.

3. The laminate for thermoforming according to claim 1 or 2, characterized in that: The hard coating layer includes 0.0001 to 5 wt % of the polymerization inhibitor.

4. The laminate for thermoforming according to claim 1 or 2, characterized in that: The active energy ray-curable resin having a (meth)acryloyl group has a (meth)acrylate skeleton.

5. The laminate for thermoforming according to claim 1 or 2, characterized in that: The hard coating layer comprises nanoparticles.

6. The laminate for thermoforming according to claim 1 or 2, characterized in that: The hard coating layer includes a leveling agent.

7. The laminate for thermoforming according to claim 1 or 2, characterized in that: Before lamination with the hard coat layer, the adhesion surface of the protective film as the surface on the hard coat layer side has a surface free energy value of 30.0 mN / m or more, the surface free energy value being calculated from the average contact angles of water and diiodomethane based on the OWRK method.

8. The laminate for thermoforming according to claim 1 or 2, characterized in that: The surface roughness Sa of the adhesion surface of the protective film has a value of 0.1 μm or less.

9. The laminate for thermoforming according to claim 1 or 2, characterized in that: The hard coating layer is ultraviolet curable.

10. The laminate for thermoforming according to claim 1 or 2, characterized in that: The thermoplastic resin contains aromatic polycarbonate.

11. The laminate for thermoforming according to claim 10, characterized in that: The aromatic polycarbonate includes bisphenol A type polycarbonate.

12. The laminate for thermoforming according to claim 1 or 2, characterized in that: The substrate layer includes at least two layers of an acrylic resin layer and an aromatic polycarbonate layer.

13. A method for forming a laminate for thermoforming, characterized in that: The method comprises a heat forming step of heating the laminate for heat forming according to any one of claims 1 to 12 in a state where the protective film is attached.

14. A molded article, characterized in that: This is a molded product obtained by molding the laminate for thermoforming according to any one of claims 1 to 12.

15. An article obtained by irradiating the molded product according to claim 14 with active energy rays.

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