Photocurable resin composition, fuel cell, and sealing method

Abstract

An object of the present invention is to provide a photocurable resin composition that maintains high tensile strength and high strength properties of a cured product and exhibits a high degree of cure after light irradiation. A photocurable resin composition characterized by comprising the following components (A) to (C): component (A): a polyisobutylene resin containing one or more (meth)acryloyl groups and -[CH2C(CH3)2]- units; component (B): an acrylate monomer having an alicyclic hydrocarbon group having 5 to 25 carbon atoms as component (b1); and component (b2): an acrylate monomer having a linear or branched alkyl group having 11 to 30 carbon atoms; and component (C): a photoradical polymerization initiator.

Description

Technical Field

[0001] The present invention relates to a photocurable resin composition, a fuel cell and a sealing method. Background Art

[0002] In recent years, fuel cells have attracted attention as new energy systems for automobiles and homes. A fuel cell is a power generation device that extracts electricity by chemically reacting hydrogen and oxygen. In addition, fuel cells are clean, next-generation power generation devices because they have high energy efficiency during power generation and produce water through the reaction of hydrogen and oxygen. Fuel cells include four types: solid polymer fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells. Among them, solid polymer fuel cells are expected to be used in applications such as automotive power sources, household power generation devices, small power supplies for electronic devices such as mobile phones, and emergency power supplies due to their relatively low operating temperature (around 80°C) and high power generation efficiency.

[0003] like Figure 1 As shown, the battery cell 1 of the solid polymer fuel cell has a structure including an electrolyte membrane electrode assembly 5 (MEA), a frame 6 supporting the aforementioned MEA and a diaphragm 2 forming a gas flow path, and the electrolyte membrane electrode assembly 5 has a structure in which a polymer electrolyte membrane 4 is clamped between an air electrode 3a and a fuel electrode 3b.

[0004] In order to start the solid polymer fuel cell, it is necessary to supply a fuel gas containing hydrogen to the fuel electrode (anode) 3b and an oxidizing gas containing oxygen to the air electrode (cathode) 3a in a separately isolated manner. This is because there is a risk that if the isolation is insufficient, the gas on one side will mix with the gas on the other side, resulting in a decrease in power generation efficiency. Based on this background, sealants are mostly used to prevent leakage of fuel gas, oxygen, etc. Specifically, a sealing portion 7 formed using a sealant is arranged between adjacent diaphragms 2, between the diaphragm 2 and the frame 6, between the frame 6 and the polymer electrolyte membrane 4 or MEA 5, etc.

[0005] As sealants for polymer electrolyte fuel cells, from the perspective of providing rubber elastic bodies with excellent gas permeability resistance, low moisture permeability, heat resistance, acid resistance, and flexibility, heat-curable resin compositions using polyisobutylene polymers through a hydrosilylation reaction (see JP-A-2004-111146), heat-curable resin compositions using fluoropolyether compounds through a hydrosilylation reaction (see JP-A-2004-075824 (corresponding to U.S. Patent Application Publication No. 2005 / 043480)), heat-curable resin compositions using fluoropolymers through a hydrosilylation reaction (see JP-A-2007-100099), and heat-curable resin compositions using ethylene-propylene-diene rubber (see JP-A-2013-229323) have been studied. Yet, the heat-curable resin compositions of Japanese Patent Laid-Open No. 2004-111146, Japanese Patent Laid-Open No. 2004-075824, Japanese Patent Laid-Open No. 2007-100099 and Japanese Patent Laid-Open No. 2013-229323 are owing to needing heating process in order to solidify, therefore there is the problem of consuming process time.For this reason, the light-curable resin compositions that can realize the production takt time of shortening curing process are noticed. In Japanese Patent Laid-Open No. 2-88614 (corresponding to European Patent No. 0353471 specification), a kind of polymer composition is disclosed, it contains the telechelic polyisobutylene polymer with 2 or 3 terminal acrylate groups, reactive diluent. Summary of the Invention

[0006] It has been reported that the aforementioned photocurable resin compositions are used in the bonding of polymer electrolyte membranes, etc. However, if the degree of cure after light irradiation is low and the reaction is insufficient, there is a possibility that volatile components will be generated from the cured product and adhere to the catalyst layer, thereby causing a decrease in power generation performance (see International Publication No. 2009 / 047908 and Japanese Patent Application Laid-Open No. 2009-096413). In addition, the cured product of the polymer composition disclosed in Japanese Patent Application Laid-Open No. 2-88614 has high tensile strength and high tensile strength properties, but has problems in that the degree of cure after light irradiation is low and volatile components are easily generated from the cured product.

[0007] The present invention has been made in view of the above-mentioned circumstances, and provides a photocurable resin composition which can maintain high tensile strength and high strength properties of a cured product and has a high degree of cure after light irradiation.

[0008] Hereinafter, the gist of the present invention will be described.

[0009] [1] A photocurable resin composition characterized in that it contains the following components (A) to (C), namely

[0010] Component (A): a polyisobutylene resin containing one or more (meth)acryloyl groups and -[CH2C(CH3)2]- units,

[0011] (B) component: an acrylate monomer having an alicyclic hydrocarbon group having 5 to 25 carbon atoms as component (b1) and an acrylate monomer having a linear or branched alkyl group having 11 to 30 carbon atoms as component (b2),

[0012] Component (C): a photoradical polymerization initiator.

[0013] [2] The photocurable resin composition according to [1], wherein the component (A) is a polyisobutylene resin represented by the following general formula (1):

[0014]

[0015] (In general formula (1), R 1 represents a monovalent or polyvalent aromatic hydrocarbon group, or a monovalent or polyvalent aliphatic hydrocarbon group, PIB represents a polyisobutylene skeleton containing the aforementioned -[CH2C(CH3)2]- unit, R 4 represents a divalent hydrocarbon group having 2 to 6 carbon atoms, R 2 and R 3 Each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R 5 represents a hydrogen atom or a methyl group, and n is an integer from 1 to 6.

[0016] [3] The photocurable resin composition according to [1] or [2], comprising 20 to 95 parts by mass of the component (b1) and 3 to 70 parts by mass of the component (b2) per 100 parts by mass of the component (A).

[0017] [4] The photocurable resin composition according to any one of [1] to [3], wherein the component (b1) is one or more selected from the group consisting of cyclohexyl acrylate, trimethylcyclohexyl acrylate, 4-tert-butylcyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyacrylate, isobornyl acrylate, and adamantyl acrylate,

[0018] The component (b2) is at least one selected from the group consisting of isostearyl acrylate, stearyl acrylate, tridecyl acrylate, lauryl acrylate, tetradecyl acrylate, pentadecyl acrylate, hexadecyl acrylate, heptadecyl acrylate, and octadecyl acrylate.

[0019] [5] A curable sealant for a fuel cell, comprising the photocurable resin composition according to any one of [1] to [4].

[0020] [6] The curable sealant for fuel cells according to [5] is a curable sealant for fuel cells used around one or more components selected from the group consisting of a diaphragm, a frame, a polymer electrolyte membrane, a fuel electrode, an air electrode and an electrolyte membrane electrode assembly as components of the fuel cell.

[0021] [7] The curable sealant for a fuel cell according to [6], wherein the curable sealant for a fuel cell is a sealant between adjacent diaphragms in a fuel cell, or a sealant between a frame of a fuel cell and a polymer electrolyte membrane or an electrolyte membrane electrode assembly.

[0022] [8] The curable sealant for a fuel cell according to any one of [5] to [7], wherein the curable sealant for a fuel cell is a curable sealant for a polymer electrolyte fuel cell.

[0023] [9] A cured product obtained by irradiating the photocurable resin composition according to any one of [1] to [4] or the curable sealant for a fuel cell according to any one of [5] to [8] with light.

[0024]

[10] A fuel cell, wherein a sealing portion between adjacent separators in the fuel cell, or a sealing portion between a frame of the fuel cell and a polymer electrolyte membrane or an electrolyte membrane electrode assembly comprises the cured product described in [9].

[0025]

[11] The fuel cell according to

[10] , wherein the fuel cell is a solid polymer fuel cell.

[0026]

[12] A sealing method for sealing at least a portion between two flanges.

[0027] At least one of the aforementioned flanges is a flange that can transmit active energy rays,

[0028] The method comprises:

[0029] A step of applying the photocurable resin composition described in any one of [1] to [4] on a surface of a flange;

[0030] a step of laminating the flange coated with the photocurable resin composition to another flange via the photocurable resin composition; and

[0031] A step of irradiating the photocurable resin composition with active energy rays through the flanges that are permeable to the active energy rays to cure the photocurable resin composition and seal at least a portion between the two flanges.

[0032]

[13] A sealing method for sealing at least a portion between two flanges.

[0033] The method comprises:

[0034] A step of applying the photocurable resin composition described in any one of [1] to [4] on a surface of a flange;

[0035] irradiating the photocurable resin composition with active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition on the one flange; and

[0036] The step of placing the other flange on the gasket, and press-bonding the one flange and the other flange with the gasket interposed therebetween to seal at least a portion between the two flanges.

[0037]

[14] A sealing method for sealing at least a portion between two flanges.

[0038] The method comprises:

[0039] a step of arranging a gasket forming mold on one flange;

[0040] A step of injecting the photocurable resin composition described in any one of [1] to [4] into at least a portion of the gap between the gasket forming mold and the one flange;

[0041] irradiating the photocurable resin composition with active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition on the one flange;

[0042] the step of removing the mold from the one flange; and

[0043] The step of placing the other flange on the gasket, and press-bonding the one flange and the other flange with the gasket interposed therebetween to seal at least a portion between the two flanges. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a schematic cross-sectional view of a single cell of a fuel cell.

[0045] Figure 2 This is a schematic diagram showing the entire fuel cell.

[0046] In the figure: 1 - battery cell of solid polymer fuel cell, 2 - diaphragm, 3a - air electrode (cathode), 3b - fuel electrode (anode), 4 - polymer electrolyte membrane, 5 - electrolyte membrane electrode assembly (MEA), 6 - frame, 7 - sealing part, 8a - oxidation gas flow path, 8b - fuel gas flow path, 9 - cooling water flow path, 10 - battery pack, 11 - solid polymer fuel cell. DETAILED DESCRIPTION

[0047] One embodiment of the present invention is a photocurable resin composition, characterized in that it contains the following (A) to (C) components, namely

[0048] Component (A): a polyisobutylene resin containing one or more (meth)acryloyl groups and -[CH2C(CH3)2]- units,

[0049] (B) component: (b1) component: an acrylate monomer having an alicyclic hydrocarbon group having 5 to 25 carbon atoms and (b2) component: an acrylate monomer having a linear or branched alkyl group having 11 to 30 carbon atoms,

[0050] Component (C): a photoradical polymerization initiator.

[0051] According to the present invention, a photocurable resin composition can be provided which can maintain high tensile strength and high strength properties of a cured product and has a high degree of cure after light irradiation.

[0052] Hereinafter, the details of the invention will be described.

[0053] <(A)Component>

[0054] The component (A) used in the present invention is not particularly limited as long as it is a polyisobutylene resin (polymer having a polyisobutylene skeleton) having one or more (meth)acryloyl groups and containing -[CH2C(CH3)2]- units. Component (A) may contain, for example, -[CH2C(CH3)2]- units (polyisobutylene skeleton), or may be a polymer containing "constituent units other than -[CH2C(CH3)2]- units." Component (A) preferably contains -[CH2C(CH3)2]- units in an amount of, for example, 70% by mass or more, preferably 75% by mass or more, and more preferably 80% by mass or more, relative to the total amount of the constituent units. Component (A) preferably contains -[CH2C(CH3)2]- units in an amount of, for example, less than 100% by mass, in another embodiment, 95% by mass or less, and in yet another embodiment, 90% by mass or less, relative to the total amount of the constituent units. It is appropriate that component (A) has preferably 1 to 12, more preferably 2 to 8, further preferably 2 to 4, and particularly preferably 2 (meth)acryloyl groups. In the present invention, the so-called polymer is not limited by theory but can be defined as, for example, a compound having a structure with a monomer repeating unit in the main chain of the polymer and containing 100 or more repeating units. In addition, the (meth)acryloyl group may be present in either the side chain and / or the terminal of the molecule, but from the viewpoint of excellent high tensile strength and high strength cured product properties, it is preferably present at the terminal of the molecule.

[0055] As the aforementioned component (A), from the viewpoint of obtaining a photocurable resin composition having excellent high tensile strength and high strength cured product properties, a polyisobutylene resin represented by the following general formula (1) is preferred. As a specific example of the component (A), a polyisobutylene resin having a (meth)acryloyloxyalkoxyphenyl group can be cited. It should be noted that the main skeleton of the component (A) in the present invention is a polyisobutylene skeleton, but in addition to mainly using isobutylene as a monomer constituting the polyisobutylene skeleton, other monomers can also be used for copolymerization as long as they do not impair the effects of the present invention. It should be noted that from the perspective of obtaining a photocurable resin composition that can cope with coating based on screen printing, the component (A) is further preferably in a liquid state at room temperature (25°C).

[0056]

[0057] In the general formula (1), R 1represents a monovalent or polyvalent aromatic hydrocarbon group, or a monovalent or polyvalent aliphatic hydrocarbon group, preferably a polyvalent aromatic hydrocarbon group, and particularly preferably a divalent phenylene group. In this case, the polyvalent aromatic hydrocarbon group and the polyvalent aliphatic hydrocarbon group refer to aromatic hydrocarbon groups and aliphatic hydrocarbon groups having 2 to 6 valencies, respectively. PIB represents a polyisobutylene skeleton containing (or consisting of) the aforementioned -[CH2C(CH3)2]- units. R 4 represents a divalent hydrocarbon group having 2 to 6 carbon atoms, preferably a divalent hydrocarbon group having 2 or 3 carbon atoms. Preferred examples of the divalent hydrocarbon group include alkylene, alkenylene, and alkynylene. The divalent hydrocarbon group may have any substituent such as a halogen atom, an amino group, a cyano group, a nitro group, or a hydroxyl group. 2 and R 3 Each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrogen atom. Examples of the monovalent hydrocarbon group include alkyl, alkenyl, and alkynyl groups, and these monovalent hydrocarbon groups may have any substituents such as halogen atoms, amino groups, cyano groups, nitro groups, and hydroxyl groups. 5 represents a hydrogen atom or a methyl group. n is an integer of 1 to 6, and is particularly preferably an integer of 2 to 4. When n is 2 or more, PIB, R 2 、R 3 、R 4 、R 5 They can be the same or different.

[0058] The molecular weight of the (A) component in the present invention is not particularly limited. From the perspective of being able to cope with coating based on screen printing and excellent properties of high-tensile and high-strength cured products, the number average molecular weight obtained based on chromatographic measurement is, for example, preferably 200 to 500,000, more preferably 1,000 to 100,000, and particularly preferably 3,000 to 50,000. It should be noted that the above number average molecular weight is calculated using a standard polystyrene conversion method using size exclusion chromatography (SEC). When two or more (A) components are used in combination, it is preferred that the number average molecular weight of at least one of them is within the above range.

[0059] The viscosity of the component (A) in the present invention at 25°C is not particularly limited, but from the perspective of operability, it is, for example, 5 Pa·s or more, preferably 50 Pa·s or more, more preferably 100 Pa·s or more, for example 3000 Pa·s or less, preferably 2500 Pa·s or less, more preferably 2000 Pa·s or less. A particularly preferred viscosity is 1750 Pa·s or less. Unless otherwise specified, the viscosity is measured using a cone-plate viscometer at 25°C. When two or more components (A) are used in combination, it is preferred that the viscosity of at least one of them be within the above range.

[0060] The method for producing the component (A) is not particularly limited, and a known method can be used. Examples include methods disclosed in Polymer Bulletin, Vol. 6, pp. 135-141 (1981), TPLiao and JPMorgan and Polymer Bulletin, Vol. 20, pp. 253-260 (1988), and Puskas et al., which are methods for reacting terminal hydroxy polyisobutylene with chlorinated acryloyl or chlorinated methacryloyl to obtain the component (A). Other methods for producing the component (A) include methods for reacting terminal hydroxy polyisobutylene with a compound having a (meth) acryloyl group and an isocyanate group, methods for reacting terminal hydroxy polyisobutylene with a compound having an isocyanate group and a compound having a (meth) acryloyl group and a hydroxyl group, and methods for reacting terminal hydroxy polyisobutylene with (meth) acrylic acid or a lower ester of (meth) acrylic acid using a dehydration esterification method or an ester exchange method.

[0061] The method for producing the polyisobutylene resin represented by the general formula (1) is not particularly limited, but a preferred method is the method disclosed in Japanese Patent Application Laid-Open No. 2013-216782, wherein a halogen-terminated polyisobutylene is reacted with a compound having a (meth)acryloyl group and a phenoxy group as represented by the following general formula (2). The halogen-terminated polyisobutylene can be obtained by a known method, for example, by cationic polymerization, more preferably by living cationic polymerization.

[0062]

[0063] In the general formula (2), R 2 、R 3 、R 4 and R 5 It can be as defined in the above general formula (1). Specifically, R 4 represents a divalent hydrocarbon group having 2 to 6 carbon atoms. 2 and R 3 R each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. 5 represents a hydrogen atom or a methyl group. Examples of the compound represented by the above formula (2) include phenoxymethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypropyl (meth)acrylate, phenoxybutyl (meth)acrylate, and phenoxypentyl (meth)acrylate. Preferred examples include phenoxyethyl (meth)acrylate, phenoxypropyl (meth)acrylate, phenoxybutyl (meth)acrylate, and phenoxypentyl (meth)acrylate.

[0064] <(B) Ingredient>

[0065] The (B) component of the present invention is the (b1) component: an acrylate monomer having an alicyclic hydrocarbon group with 5 to 25 carbon atoms and the (b2) component: an acrylate monomer having a linear or branched alkyl group with 11 to 30 carbon atoms. By combining the aforementioned (b1) component and the aforementioned (b2) component, a photocurable resin composition can be obtained that can maintain high tensile strength and high strength cured product properties and has a high degree of curing after light irradiation. In addition, by combining the aforementioned (b1) component and the aforementioned (b2) component, the effects of low viscosity and excellent adhesion to PEN used in the frame can also be exerted. From the viewpoint of low viscosity and excellent adhesion to polyethylene naphthalate (PEN) and high tensile strength and high strength cured product properties, the acrylate monomer of the aforementioned (B) component is preferably a monofunctional acrylate monomer. The aforementioned (B) component is, for example, H2C=CH-C(=O)-OR 6 The compound shown. 6 The compound which is an alicyclic hydrocarbon group having 5 to 25 carbon atoms corresponds to the component (b1), and R 6 The compound having a linear or branched alkyl group having 11 to 30 carbon atoms corresponds to the component (b2).

[0066] Examples of the alicyclic hydrocarbon group having 5 to 25 carbon atoms in the component (b1) include cyclohexyl, trimethylcyclohexyl, 4-tert-butylcyclohexyl, dicyclopentanyl, dicyclopentenyl, isobornyl, and adamantyl. The component (b1) is not particularly limited, and examples thereof include cyclohexyl acrylate, trimethylcyclohexyl acrylate, 4-tert-butylcyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, isobornyl acrylate, and adamantyl acrylate. Among these, 4-tert-butylcyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, and isobornyl acrylate are preferred. The component (b1) may be used alone or as a mixture of two or more. In addition, commercially available products of the aforementioned component (b1) are not particularly limited, and examples thereof include SR-506 (isobornyl acrylate, manufactured by Sartomer Co., Ltd.), FA-513AS (dicyclopentyl acrylate, manufactured by Showa Denko Materials Co., Ltd.), TBCHA (4-tert-butylcyclohexyl acrylate, manufactured by KJ Chemicals Co., Ltd.), and IB-XA (isobornyl acrylate, manufactured by Kyoeisha Chemical Co., Ltd.).

[0067] The carbon number of the aforementioned (b2) component is 25 or less, preferably 23 or less, and more preferably 21 or less. In addition, as the aforementioned (b2) component, if an acrylate monomer with a straight-chain alkyl group is selected, the degree of curing can be made more excellent, and if an acrylate monomer with a branched-chain alkyl group is selected, a cured product with higher strength can be obtained. In addition, as the aforementioned (b2) component, for example, isostearyl acrylate, stearyl acrylate, tridecyl acrylate, lauryl acrylate, tetradecyl acrylate, pentadecyl acrylate, hexadecyl acrylate, heptadecyl acrylate, octyl nonyl acrylate, etc. can be listed, among which isostearyl acrylate, tridecyl acrylate, lauryl acrylate, tetradecyl acrylate are preferred. The (b2) component can be used alone or in the form of a mixture of two or more. There are no particular restrictions on commercially available products of the aforementioned component (b2), and examples include ISTA (isostearyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), STA (stearyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), SR489D (tridecyl acrylate, manufactured by Sartomer), LA (lauryl acrylate, manufactured by BASF), and LA (lauryl acrylate, manufactured by Kyoeisha Chemical Co., Ltd.).

[0068] As the amount of the aforementioned (B) component, it is preferred that the (b1) component be included in the range of 20 to 95 parts by mass and the (b2) component be included in the range of 3 to 70 parts by mass relative to 100 parts by mass of the (A) component, more preferably the (b1) component be included in the range of 30 to 90 parts by mass and the (b2) component be included in the range of 5 to 60 parts by mass, further preferably the (b1) component be included in the range of 40 to 85 parts by mass and the (b2) component be included in the range of 7 to 50 parts by mass, further preferably the (b1) component be included in the range of 44 to 78 parts by mass and the (b2) component be included in the range of 9 to 44 parts by mass. By making it within the above range, a photocurable resin composition having a lower viscosity, high tensile strength and high curing property can be provided, and a high degree of curing after light irradiation can be provided. It should be noted that when using multiple (A) components, the total amount thereof preferably satisfies the above relationship. Similarly, when using multiple (b1) components or multiple (b2) components, the total amount thereof preferably satisfies the above relationship respectively.

[0069] <(C) Ingredient>

[0070] The photoradical polymerization initiator of the component (C) used in the present invention is not limited as long as it is a compound that generates free radicals by irradiating active energy rays. Here, the so-called active energy rays include radiation such as α rays or β rays, electromagnetic waves such as γ rays or X rays, electron beams, ultraviolet rays with a wavelength of about 100 to 400 nm, visible light with a wavelength of about 400 to 800 nm, and all broad lights, preferably ultraviolet rays. As component (C), for example, acetophenone-based photoradical polymerization initiators, benzoin-based photoradical polymerization initiators, benzophenone-based photoradical polymerization initiators, thioxanthone-based photoradical polymerization initiators, acylphosphine oxide-based photoradical polymerization initiators, titanocene-based photoradical polymerization initiators, etc. can be listed. Among them, from the viewpoint of obtaining a photocurable resin composition that can be photocured in a shorter time by irradiating active energy rays, acetophenone-based photoradical polymerization initiators and acylphosphine oxide-based photoradical polymerization initiators are preferred. In addition, these polymerization initiators can be used alone or in combination of two or more.

[0071] Examples of the acetophenone-based photoradical polymerization initiator include, but are not limited to, diethoxyacetophenone, 1-phenyl-2-hydroxy-2-methylpropane-1-one, benzyl dimethyl ketal, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-2-morpholino(4-thiomethylphenyl)propane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone oligomers. Commercially available products of the acetophenone-based photoradical polymerization initiator include Omnirad (registered trademark, hereinafter the same) 184, Omnirad 1173, Omnirad 2959, Omnirad 127 (manufactured by IGM Resins BV), and ESACURE (registered trademark) KIP-150 (manufactured by IGM Resins BV).

[0072] Examples of the acylphosphine oxide-based photoradical polymerization initiator include, but are not limited to, bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. Commercially available acylphosphine oxide-based photoradical polymerization initiators include Omnirad TPO, Omnirad 819, and Omnirad 819DW (manufactured by IGM Resins BV).

[0073] The amount of the aforementioned (C) component is not particularly limited, and is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass, and particularly preferably 1.1 to 10 parts by mass relative to 100 parts by mass of the aforementioned (A) component. By making it within the above range, a photocurable resin composition that can better cope with coating based on screen printing and can be photocured in a shorter time can be provided. It should be noted that when using multiple (A) components, the total amount thereof preferably satisfies the above relationship. Similarly, when using multiple (C) components, the total amount thereof preferably satisfies the above relationship.

[0074] <Optional ingredients>

[0075] The composition of the present invention may contain additives such as an oligomer or polymer having a (meth)acryloyl group (excluding component (A) of the present invention), a (meth)acrylate monomer other than component (B), an inorganic filler, an organic peroxide, a curing accelerator, a storage stabilizer, an antioxidant, a light stabilizer, a plasticizer, a pigment, a flame retardant, and a surfactant, within a range that does not impair the purpose of the present invention.

[0076] The oligomer or polymer having a (meth)acryloyl group (excluding the component (A) of the present invention) is not particularly limited, and examples thereof include urethane (meth)acrylates having a polybutadiene skeleton, urethane (meth)acrylates having a hydrogenated polybutadiene skeleton, urethane (meth)acrylates having a polycarbonate skeleton, urethane (meth)acrylates having a polyether skeleton, urethane (meth)acrylates having a polyester skeleton, urethane (meth)acrylates having a castor oil skeleton, isoprene (meth)acrylates, hydrogenated isoprene (meth)acrylates, epoxy (meth)acrylates, and (meth)acryloyl group-containing acrylic polymers. Among them, from the perspective of excellent compatibility with the (A) component and the (B) component of the present invention, polybutadiene skeleton urethane (meth) acrylate, hydrogenated polybutadiene skeleton urethane (meth) acrylate, castor oil skeleton urethane (meth) acrylate, isoprene (meth) acrylate, and hydrogenated isoprene (meth) acrylate are preferred. It should be noted that in the present invention, oligomers refer to compounds having a structure with a repeating unit of a monomer on the main chain and containing 2 to 100 repeating units. In addition, they can be used alone or in combination of two or more. In addition, with respect to (meth) acrylate monomers other than component (B), the (meth) acrylate monomer can be contained within the range that does not impair the purpose of the present invention. However, if the purpose is impaired, it is preferably not contained.

[0077] The photocurable resin composition of the present invention may contain an inorganic filler to the extent that it does not hinder the storage stability for the purpose of improving the elastic modulus and fluidity of the cured product. Specifically, inorganic powders, metallic powders, etc. can be mentioned. As fillers for inorganic powders, glass, fumed silica, alumina, mica, ceramics, silicone rubber powder, calcium carbonate, aluminum nitride, carbon powder, kaolin clay, dry clay minerals, dry diatomaceous earth, etc. can be mentioned. The amount of inorganic powder added is preferably about 0.1 to 100 parts by mass relative to 100 parts by mass of the aforementioned (A) component.

[0078] For the purpose of adjusting the viscosity of photocurable resin composition or improving the mechanical strength of cured product, fumed silica can be coordinated.Preferably, fumed silica etc. after hydrophobizing treatment with organochlorosilanes, polyorganosiloxane, hexamethyldisilazane etc. can be used.As the specific example of fumed silica, the commercially available products such as trade name Aerosil (registered trademark) R974, R972, R972V, R972CF, R805, R812, R812S, R816, R8200, RY200, RX200, RY200S, R202 of such as Japan Aerosil Co., Ltd. can be enumerated.

[0079] The photocurable resin composition of the present invention may contain an organic peroxide for the purpose of imparting curability based on heating or redox reaction. If a redox reaction is used, free radical species can be generated at room temperature, so it is preferred. As the aforementioned organic peroxide, there is no particular limitation, and examples thereof include: methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, acetylacetone peroxide and other peroxide ketones; 1,1-bis (tert-butyl peroxy) -3,3,5-trimethylcyclohexane, 1,1-bis (tert-butyl peroxy) cyclohexane, 2,2-bis (tert-butyl peroxy) octane, n-butyl -4,4-bis (tert-butyl peroxy) valerate, 2,2-bis (tert-butyl peroxy) butane and other peroxy ketals; tert-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, Hydroperoxides such as p-menthane hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide; dialkyl peroxides such as di-tert-butyl peroxide, tert-butylcumyl peroxide, dicumyl peroxide, α,α'-bis(tert-butylperoxym-isopropyl)benzene, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, and 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3; acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, and succinic acid peroxide , benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, m-toluoyl peroxide and other diacyl peroxides; diisopropyl peroxydicarbonate, di(2-ethylhexyl) peroxydicarbonate, di-n-propyl peroxydicarbonate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, dimyristyl peroxydicarbonate, di(2-ethoxyethyl) peroxydicarbonate, dimethoxyisopropyl peroxydicarbonate, di(3-methyl-3-methoxybutyl) peroxydicarbonate, diallyl peroxydicarbonate and other peroxydicarbonates; tert-butyl peroxyacetate, tert-butyl peroxyisobutyrate, tert-butyl peroxypivalate, Peroxyesters such as tert-butyl peroxyneodecanoate, cumyl peroxyneodecanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxylaurate, tert-butyl peroxybenzoate, di-tert-butyl peroxyisophthalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, tert-butyl peroxymaleate, tert-butyl peroxyisopropylcarbonate, cumyl peroxyoctanoate, tert-hexyl peroxyneodecanoate, tert-hexyl peroxypivalate, tert-butyl peroxyneohexanoate, tert-hexyl peroxyneohexanoate, and cumyl peroxyneohexanoate; and acetylcyclohexylsulfonyl peroxide, tert-butyl peroxyallylcarbonate, etc. These organic peroxides may be used alone or in combination of two or more.Among them, cumene hydroperoxide is preferably used from the viewpoint of curability.

[0080] When an organic peroxide is used in the present invention, a curing accelerator may be added for the purpose of promoting the redox reaction. Such a curing accelerator is not particularly limited, but preferably saccharin (o-sulfonylbenzylimide), a hydrazine compound, an amine compound, a thiol compound, a transition metal-containing compound, etc. are used.

[0081] Examples of the hydrazine compound include 1-acetyl-2-phenylhydrazine, 1-acetyl-2 (p-tolyl) hydrazine, 1-benzoyl-2-phenylhydrazine, 1-(1',1',1'-trifluoro)acetyl-2-phenylhydrazine, 1,5-diphenylcarbohydrazide, 1-formyl-2-phenylhydrazine, 1-acetyl-2-(p-bromophenyl) hydrazine, 1-acetyl-2-(p-nitrophenyl) hydrazine, 1-acetyl-2-(2'-phenylethylhydrazine), ethyl carbazate, p-nitrophenylhydrazine, and p-trisulfonylhydrazide.

[0082] Examples of the aforementioned amine compounds include 2-ethylhexylamine; heterocyclic secondary amines such as 1,2,3,4-tetrahydroquinaldine; heterocyclic tertiary amines such as quinoline, methylquinoline, quinaldine, quinoxaline, and phenazine; aromatic tertiary amines such as N,N-dimethyl-p-toluidine, N,N-dimethylanisidine, and N,N-dimethylaniline; and azole compounds such as 1,2,4-triazole, oxazole, oxadiazole, thiadiazole, benzotriazole, hydroxybenzotriazole, benzoxazole, 1,2,3-benzothiadiazole, and 3-mercaptobenzotriazole.

[0083] Examples of the thiol compound include n-dodecyl mercaptan, ethyl mercaptan, butyl mercaptan, tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, pentaerythritol tetrakis(3-mercaptopropionate), dipentaerythritol hexa(3-mercaptopropionate), trimethylolpropane tris(3-mercaptopropionate), trimethylolpropane tris(thioglycolate), and pentaerythritol tetrakis(thioglycolate).

[0084] As the transition metal-containing compound, a metal chelate complex salt is preferably used. Examples thereof include iron pentanedione, cobalt pentanedione, copper pentanedione, copper propylenediamine, copper ethylenediamine, iron naphthenate, nickel naphthenate, cobalt naphthenate, copper naphthenate, copper octoate, iron hexanoate, iron propionate, and vanadium acetylacetonate.

[0085] The aforementioned curing accelerators may be used alone or in combination of two or more. Among them, saccharin, hydrazine compounds, amine compounds, and mixtures of transition metal-containing compounds are more preferred because they exhibit good curing accelerating effects.

[0086] The photocurable resin composition of the present invention may contain a storage stabilizer. Examples of the storage stabilizer include free radical absorbers such as benzoquinone, hydroquinone, and hydroquinone monomethyl ether, and metal chelating agents such as ethylenediaminetetraacetic acid or its 2-sodium salt, oxalic acid, acetylacetone, and o-aminophenol.

[0087] The photocurable resin composition of the present invention may contain an antioxidant. Examples of the antioxidant include quinone compounds such as β-naphthoquinone, 2-methoxy-1,4-naphthoquinone, methyl hydroquinone, hydroquinone, hydroquinone monomethyl ether, mono-tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, p-benzoquinone, 2,5-diphenyl-p-benzoquinone, and 2,5-di-tert-butyl-p-benzoquinone; 2,2-methylene-bis(4-methyl-6-tert-butylphenol), catechol, tert-butylcatechol, 2-butyl-4-hydroxyanisole, 2,6-di-tert-butyl-p-cresol, 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6 -di-tert-amylphenyl acrylate, 4,4'-butylenebis(6-tert-butyl-3-methylphenol), 4,4'-thiobis(6-tert-butyl-3-methylphenol), 3,9-bis[2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexane-1,6-diylbis[3- (3,5-di-tert-butyl-4-hydroxyphenyl)propionamide], phenylpropionic acid-3,5-bis(1,1-dimethylethyl)-4-hydroxy-C7-C9 side chain alkyl ester, 2,4-dimethyl-6-(1-methylpentadecyl)phenol, diethyl [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate, 3,3',3",5,5',5"-hexa-tert-butyl-a,a',a"-(mesitylene-2,4,6-tolyl)tri-p-cresol, diethylbis[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate calcium, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3 Phenols such as 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)trione, 1,3,5-tris[(4-tert-butyl-3-hydroxy-2,6-xylyl)methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)trione, reaction products of N-phenylaniline and 2,4,6-trimethylpentene, 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol, and picric acid;Tris(2,4-di-tert-butylphenyl)phosphite, tris[2-[[2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphefin-6-yl]oxy]ethyl]amine, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, tetrakis(2,4-di-tert-butylphenyl)[1,1-diphenyl]-4,4'-diylbisphosphonite, 6-[3-(3- Phosphorus compounds such as [tert-butyl-4-hydroxy-5-methylphenyl]propoxy]-2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphefin; sulfur compounds such as dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, distearyl 3,3'-thiodipropionate, pentaerythritol tetrakis(3-laurylthiopropionate), and 2-mercaptobenzimidazole; amine compounds such as phenothiazine; lactone compounds; vitamin E compounds, etc. Among them, phenolic compounds are preferred.

[0088] The photocurable resin composition of the present invention may contain a light stabilizer. Examples of the light stabilizer include bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1-[2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-2,2,6,6-tetramethylpiperidine, 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methacrylate butylmalonate, bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) sebacate, reaction products of 1,1-dimethylethyl hydroperoxide and octane, N,N',N",N"'-tetrakis-(4,6-bis-(butyl-(N-methyl-2,2,6,6-tetramethylpiperidin-4-yl)amino)-triazin-2-yl)-4,7-diazadecane-1,10-diamine, polycondensation of dibutylamine, 1,3,5-triazine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl-1,6-hexamethylenediamine and N-(2,2,6,6-tetramethyl-4-piperidinyl)butylamine, poly[[6-(1,1,3,3-tetramethylbutyl] ... succinic acid, polymer with dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol, 2,2,4,4-tetramethyl-20-(β-lauryloxycarbonyl)ethyl-7-oxa-3,20-diazabispiperidin-21-one, β-alanine-N-(2,2,6,6-tetramethyl-4-piperidinyl)-dodecyl / tetradecyl ester, N-acetyl-3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidinyl)imino hindered amine compounds such as (4-methoxyphenyl)-methylene)-bis(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione, 2,2,4,4-tetramethyl-7-oxa-3,20-diazabispiro[5,1,11,2]heneicosane-21-one, 2,2,4,4-tetramethyl-21-oxa-3,20-diazabicyclo-[5,1,11,2]-heneicosane-20-propionate dodecyl / tetradecyl ester, malonic acid-[(4-methoxyphenyl)-methylene]-bis(1,2,2,6,6-pentamethyl-4-piperidyl) ester, higher fatty acid esters of 2,2,6,6-tetramethyl-4-piperidinol, and N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,3-benzenedicarboxamide;Benzophenone compounds such as octabenzone; 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-〔2-hydroxy-3-(3,4,5,6-tetrahydrophthalimide-methyl)-5-methylphenyl〕benzotriazole, 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-tert-pentylphenyl)benzotriazole Benzotriazole compounds such as benzotriazole, the reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate and polyethylene glycol, and 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol; benzoate compounds such as 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate; and triazine compounds such as 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]phenol. Hindered amine compounds are particularly preferred.

[0089] The photocurable resin composition of the present invention may contain an adhesion-imparting agent. Examples of the adhesion-imparting agent include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, methacryloxyoctyltrimethoxysilane, vinyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyl-tri(β-methoxyethoxy)silane, γ-chloropropyltrimethoxysilane, β-(3,4-epoxy)silane, cyclohexyl)ethyl trimethoxysilane, γ-glycidoxypropyl trimethoxysilane, γ-mercaptopropyl trimethoxysilane, γ-aminopropyl triethoxysilane, N-β-(aminoethyl)-γ-aminopropyl trimethoxysilane, N-β-(aminoethyl)-γ-aminopropyl methyldimethoxysilane, γ-ureidopropyl triethoxysilane, hydroxyethyl methacrylate phosphate, methacryloyloxyoxyethyl acid phosphate, methacryloyloxyoxyethyl acid phosphate monoethylamine half salt, 2-hydroxyethyl methacrylate phosphate, etc. Among them, hydroxyethyl methacrylate phosphate, methacryloyloxyoxyethyl acid phosphate, methacryloyloxyoxyethyl acid phosphate monoethylamine half salt, 2-hydroxyethyl methacrylate phosphate, etc. are preferred. The content of the adhesion-imparting agent is preferably 0.05 to 30 parts by mass, more preferably 0.2 to 10 parts by mass, relative to 100 parts by mass of component (A).

[0090] The photocurable resin composition of the present invention can be produced by conventionally known methods. For example, it can be produced by blending predetermined amounts of components (A) to (C), and optionally, any other components, using a mixing device such as a mixer, and mixing at a temperature of preferably 10 to 70°C for preferably 0.1 to 5 hours. Furthermore, it is preferably produced under a light-shielding environment.

[0091] <Coating method>

[0092] Methods for applying the photocurable resin composition of the present invention to an adherend include dispensing using an automatic coater, spraying, inkjet coating, screen printing, gravure printing, dipping, and spin coating. Screen printing is particularly preferred because it allows the photocurable resin composition of the present invention to maintain high tensile strength and high strength properties while maintaining a high degree of cure and low viscosity after light irradiation. From the perspective of coating properties, the photocurable resin composition of the present invention is preferably in a liquid state at 25°C.

[0093] <Curing method>

[0094] The active energy ray source when curing the photocurable resin composition of the present invention by irradiating it with active energy rays such as ultraviolet rays and visible rays is not particularly limited, and examples thereof include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, sodium lamps, halogen lamps, xenon lamps, LEDs, fluorescent lamps, sunlight, and electron beam irradiation devices. From the viewpoint of the properties of the cured product, the irradiation dose of the active energy ray is preferably 3 kJ / m 2 More than 5 kJ / m 2 From the perspective of the production cycle time of the curing process, 70 kJ / m 2 Below, more preferably 60kJ / m 2 Below, particularly preferably 50 kJ / m 2 the following.

[0095] The photocurable resin composition of the present invention is not particularly limited, but preferably has a degree of cure of 75% or more, more preferably 77% or more, and even more preferably 80% or more. The degree of cure is measured by the method described in the Examples below.

[0096] <Cured product>

[0097] The cured product of the present invention can be obtained by curing the photocurable resin composition of the present invention by irradiating it with active energy rays such as ultraviolet rays using the above-mentioned curing method. The cured product of the present invention can be obtained by any curing method as long as it is a cured product obtained by curing the photocurable resin composition of the present invention.

[0098] The cured product of the present invention or the cured product obtained by curing the photocurable resin composition of the present invention is not particularly limited, but preferably has a hardness of 3 to 95, more preferably 5 to 90. The hardness of the cured product is the value measured by the method described in the Examples below.

[0099] The cured product of the present invention or the cured product obtained by curing the photocurable resin composition of the present invention is not particularly limited, but the tensile strength is preferably 1.2 MPa or greater, more preferably 1.7 MPa or greater. The tensile strength of the cured product is the value measured by the method described in the Examples below.

[0100] The cured product of the present invention or the cured product obtained by curing the photocurable resin composition of the present invention is not particularly limited, but the elongation is preferably 310% or greater, more preferably 350% or greater. The elongation of the cured product is the value measured by the method described in the Examples below.

[0101] <Application and sealant>

[0102] A preferred application for the photocurable resin composition of the present invention or its cured product is as a curable sealant. In the present invention, the term "sealant" also includes applications such as adhesives, coatings, casting agents, and potting agents. When used in such applications, the photocurable resin composition of the present invention is preferably liquid at 25°C.

[0103] Specific applications of sealants include fuel cells, solar cells, dye-sensitized solar cells, lithium-ion batteries, electrolytic capacitors, liquid crystal displays, organic EL displays, electronic paper, LEDs, hard disk devices, photodiodes, optical communication circuits, wires, cables, optical fibers, optical isolators, IC cards, and other laminates, sensors, substrates, and pharmaceutical and medical instruments and equipment, because the photocurable resin composition of the present invention or its cured product is a rubber elastic body with low gas and moisture permeability, excellent heat resistance, acid resistance, and flexibility. Among these applications, the photocurable resin composition of the present invention is particularly preferred for fuel cell applications because it cures rapidly upon exposure to active energy rays such as ultraviolet light, and the cured product exhibits excellent gas barrier properties.

[0104] Fuel Cells

[0105] Fuel cells are power generation devices that generate electricity through a chemical reaction between hydrogen and oxygen. There are four types of fuel cells: polymer electrolyte fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells. Polymer electrolyte fuel cells, due to their relatively low operating temperature (around 80°C) and high power generation efficiency, are used in applications such as automotive power sources, household power generation devices, small power supplies for electronic devices such as mobile phones, and emergency power supplies.

[0106] like Figure 1 As shown, a representative solid polymer fuel cell unit 1 has a structure including an electrolyte membrane electrode assembly 5 (MEA), a frame 6 supporting the above-mentioned MEA 5, and a diaphragm 2 forming a gas flow path, wherein the electrolyte membrane electrode assembly 5 is a structure in which the polymer electrolyte membrane 4 is clamped between the air electrode 3a and the fuel electrode 3b. In addition, when the solid polymer fuel cell is started, the fuel gas (hydrogen) and the oxidizing gas (oxygen) are supplied through the oxidizing gas flow path 8a and the fuel gas flow path 8b. In addition, in order to alleviate the heat generated during power generation, cooling water flows through the flow path 9. It should be noted that a device formed by overlapping and packaging hundreds of these battery cells, such as Figure 2 A cell stack 10 called a polymer electrolyte fuel cell 11 is shown.

[0107] When fuel gas (hydrogen) is supplied to the fuel electrode and oxidizing gas (oxygen) is supplied to the oxygen electrode (air electrode), the following reactions occur at each electrode, and as a whole, a reaction to produce water occurs (H2 + 1 / 2O2 → H2O). In detail, the protons (H2) generated in the fuel electrode are + ) diffuses in the solid polymer membrane and moves toward the oxygen electrode side, and water (H2O) generated by reacting with oxygen is discharged from the oxygen electrode side.

[0108] Fuel electrode (anode): H2→2H + +2e -

[0109] Oxygen electrode (cathode): 1 / 2O2+2H + +2e - →H2O

[0110] To start a solid polymer fuel cell, a fuel gas containing hydrogen must be supplied to the anode and an oxidizing gas containing oxygen must be supplied to the cathode, each in a separate, isolated manner. This is because insufficient isolation can cause the gas from one side to mix with the gas from the other, potentially reducing power generation efficiency. Sealant is often used to prevent leakage of fuel gas, oxygen, and other gases. Specifically, sealants are used between adjacent separators, between separators and frames, and between frames and polymer electrolyte membranes or MEAs.

[0111] The sealant of the present invention is suitable for use as a curable fuel cell sealant around one or more fuel cell components selected from the group consisting of a separator, a frame, a polymer electrolyte membrane, a fuel electrode, an air electrode, and a membrane electrode assembly. In particular, the sealant of the present invention is suitable for use as a sealant between adjacent separators in a fuel cell, or as a sealant between a fuel cell frame and a polymer electrolyte membrane or a membrane electrode assembly.

[0112] As the polymer electrolyte membrane 4, a cation exchange membrane with ion conductivity can be cited. From the perspective of making the chemical properties stable and the workability at high temperatures strong, preferably a fluorine-based polymer with a sulfonic acid group shown in the following formula (3) is cited. As commercially available products, Nafion (registered trademark) manufactured by DuPont, Flemion (registered trademark) manufactured by AGC Corporation, Aciplex (registered trademark) manufactured by Asahi Kasei Corporation, etc. can be cited. Generally, the polymer electrolyte membrane is a material that is difficult to bond, but it can be bonded by using the photocurable resin composition of the present invention.

[0113]

[0114] The aforementioned fuel electrode 3b is referred to as a hydrogen electrode or anode, and a known electrode can be used. For example, an electrode in which a catalyst such as platinum, nickel, or ruthenium is supported on carbon can be used. In addition, the aforementioned air electrode 3a is referred to as an oxygen electrode or cathode, and a known electrode can be used. For example, an electrode in which a catalyst such as platinum or an alloy is supported on carbon can be used. The surface of each electrode can be provided with a gas diffusion layer that has the function of diffusing gas or moisturizing the polymer electrolyte membrane. The gas diffusion layer can use a known gas diffusion layer, and examples thereof include carbon paper, carbon cloth, and carbon fiber.

[0115] like Figure 1 As shown, the separator 2 has fine concave and convex flow paths through which the fuel gas and the oxidizing gas are supplied to the electrodes. The separator 2 is made of aluminum, stainless steel, titanium, graphite, carbon, or the like.

[0116] The frame 6 supports and reinforces the thin polymer electrolyte membrane 4 or MEA 5 so that it does not break. Examples of materials for the frame 6 include thermoplastic resins such as polyvinyl chloride, polyethylene naphthalate (PEN), polyethylene terephthalate, polypropylene, and polycarbonate. Furthermore, in order to bond components using the photocurable resin composition of the present invention or its cured product, the components are preferably light-transmissive.

[0117] The fuel cell of the present invention is characterized by being sealed by the photocurable resin composition of the present invention or its cured product. Components requiring sealing in the fuel cell include a diaphragm, a frame, a polymer electrolyte membrane, a fuel electrode, an air electrode, and an MEA, and a seal can be formed between these components. More specific sealing locations (where the seal is formed) include between adjacent diaphragms, between a diaphragm and a frame, and between a frame and a polymer electrolyte membrane or MEA.

[0118] The photocurable resin composition or sealant of the present invention can be cured by irradiating it with energy rays such as light to obtain a cured product. The photocurable resin composition or sealant of the present invention, or its cured product, can be used as a sealing portion around components such as fuel cell separators, frames, polymer electrolyte membranes, fuel electrodes, air electrodes, and electrolyte membrane electrode assemblies.

[0119] The photocurable resin composition or sealant of the present invention or a cured product thereof can be suitably used for sealing portions between adjacent separators in a fuel cell, or for sealing portions between a fuel cell frame and a polymer electrolyte membrane or a membrane electrode assembly.

[0120] The primary purpose of sealing between the diaphragm and the frame, or between the polymer electrolyte membrane or MEA and the frame, is to prevent gas mixing and leakage. The purpose of sealing between adjacent diaphragms is to prevent gas leakage and cooling water leakage from the cooling water flow path to the outside. Acid generated from the polymer electrolyte membrane creates a strongly acidic atmosphere, so the sealant is required to be acid-resistant.

[0121] Sealing method

[0122] The sealing method using the photocurable resin composition of the present invention is not particularly limited, and representative examples include form-in-place gasket (FIPG), cured-in-place gasket (CIPG), molded-in-place gasket (MIPG), and liquid injection molding.

[0123] FIPG is a method in which a photocurable resin composition is applied to one flange of a component to be sealed using an automatic coating device, for example. While the flange is in contact with the other flange, the composition is irradiated with active energy rays such as ultraviolet light from the light-transmissive flange side to cure the photocurable resin composition, thereby achieving adhesive sealing. This method can be used to seal at least a portion between the at least two flanges of a component to be sealed. In this case, at least one of the flanges is transmissive to the active energy rays. The method comprises: applying the photocurable resin composition of the present invention to the surface of at least one of the flanges; laminating the flange coated with the photocurable resin composition to the other flange via the photocurable resin composition; and irradiating the photocurable resin composition through the light-transmissive flange to cure the composition, thereby sealing at least a portion between the at least two flanges.

[0124] That is, according to one embodiment of the present invention, a method can be provided, which is a method for sealing at least a portion between two flanges, wherein at least one of the flanges is a flange that can transmit active energy rays, and the method includes: a process of coating the photocurable resin composition of the present invention on the surface of one flange; a process of bonding the flange coated with the photocurable resin composition and another flange via the photocurable resin composition; and a process of irradiating the photocurable resin composition with active energy rays through the flange that can transmit the active energy rays, curing the photocurable resin composition, and sealing at least a portion between the two flanges.

[0125] CIPG is a method that includes the following steps: applying a photocurable resin composition in a beaded form to the flange of a sealed component using a screen printing coating device, an automatic coating device, or the like, irradiating the flange with active energy rays such as ultraviolet light to cure the composition and thereby forming a gasket; and laminating the flange with another flange to perform compression sealing. This method can be used to seal at least a portion between the at least two flanges of a sealed component having at least two flanges. The method includes: applying the photocurable resin composition to at least one of the flanges; irradiating the applied photocurable resin composition with active energy rays to cure the composition and thereby forming a gasket composed of the cured product of the photocurable resin composition; and placing another flange on the gasket and press-bonding the flange coated with the photocurable resin composition and the other flange with the gasket interposed therebetween to seal at least a portion between the at least two flanges.

[0126] That is, according to one embodiment of the present invention, a method can be provided, which is a method for sealing at least a portion between two flanges, the method comprising: a process of coating the photocurable resin composition of the present invention on the surface of a flange; a process of irradiating the aforementioned photocurable resin composition with active energy rays to cure the aforementioned photocurable resin composition, and forming a gasket composed of a cured product of the aforementioned photocurable resin composition on the aforementioned flange; and a process of arranging another flange on the aforementioned gasket, crimping the aforementioned flange and the aforementioned other flange with the aforementioned gasket clamped therebetween, and sealing at least a portion between the aforementioned two flanges.

[0127] MIPG is a method in which a mold of a material that can transmit active energy rays is pre-pressed against a flange of a sealed component, a photocurable resin composition is injected into the cavity generated between the mold and the flange, and active energy rays such as ultraviolet rays are irradiated to photocure the mold to form a gasket, which is then fitted to another flange for compression sealing. It should be noted that the mold is preferably a light-transmitting material, specifically glass, polymethyl methacrylate (PMMA), polycarbonate, cycloolefin polymer, olefin, etc. can be cited. In addition, in order to easily remove the gasket from the mold after formation, the mold is preferably pre-coated with a release agent such as a fluorine-based or silicone-based release agent. This method can be used when sealing at least a portion between the at least two flanges of a sealed component having at least two flanges. The method includes: a process of arranging a gasket-forming mold on at least one of the flanges; a process of injecting the photocurable resin composition into at least a portion of a gap between the gasket-forming mold and the flange on which the mold is arranged; a process of irradiating the photocurable resin composition with the active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition; a process of removing the mold from the one flange; and a process of arranging another flange on the gasket, crimping the one flange and the other flange with the gasket clamped therebetween, thereby sealing at least a portion between the at least two flanges.

[0128] Specifically, according to one embodiment of the present invention, there is provided a method for sealing at least a portion between two flanges, the method comprising: placing a gasket-forming mold on one flange; injecting the photocurable resin composition of the present invention into at least a portion of a gap between the gasket-forming mold and the one flange; irradiating the photocurable resin composition with active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition on the one flange; removing the mold from the one flange; and placing another flange on the gasket, and pressure-bonding the one and other flanges with the gasket sandwiched therebetween to seal at least a portion between the two flanges. In this case, the gasket-forming mold is preferably transmissive to active energy rays.

[0129] Liquid injection molding is a method comprising the following steps: a photocurable resin composition is flowed into a mold of a light-transmitting material by a specific pressure, and then irradiated with active energy rays such as ultraviolet rays to photocure the composition to form a gasket. Furthermore, the gasket is sandwiched between one flange and another flange to perform compression sealing. It should be noted that the mold is preferably made of a light-transmitting material, specifically glass, PMMA, polycarbonate, cycloolefin polymer, olefin, etc. In addition, in order to facilitate removal from the mold after the gasket is formed, the mold is preferably pre-coated with a release agent such as a fluorine-based or silicone-based release agent.

[0130] Example

[0131] The present invention will be further described in detail with reference to the following examples, but the present invention is not limited to these examples.

[0132] <Production of polyisobutylene (a1) having acryloyloxyethoxyphenyl group>

[0133] After nitrogen purge, a 5 L separable flask was added with 200 mL of n-hexane and 2000 mL of chlorobutane. The mixture was then cooled to -70°C while stirring under a nitrogen atmosphere. Subsequently, 840 mL (9 mol) of isobutylene, 12 g (0.05 mol) of p-dicumyl chloride, and 1.1 g (0.012 mol) of 2-methylpyridine were added. After the reaction mixture was cooled to -70°C, 5.0 mL (0.05 mol) of titanium tetrachloride was added to initiate polymerization. Three hours after the start of polymerization, 40 g of phenoxyethyl acrylate (LIGHTACRYLATE PO-A, manufactured by Kyoeisha Chemical Co., Ltd.) and 110 mL of titanium tetrachloride were added. Stirring was continued at -70°C for 4 hours, and then 1000 mL of methanol was added to terminate the reaction.

[0134] The supernatant was separated from the reaction solution, and the solvent was distilled off. The product was then dissolved in 3000 ml of n-hexane and washed three times with 3000 ml of pure water. After reprecipitation from methanol, the solvent was distilled off under reduced pressure. The resulting polymer was vacuum-dried at 80°C for 24 hours to obtain polyisobutylene (a1) having an acryloyloxyethoxyphenyl group.

[0135] The aforementioned (a1) comprises a -[CH2C(CH3)2]- unit and contains two acryloyl groups. More specifically, (a1) is a compound wherein R 1 represents phenylene, PIB represents polyisobutylene skeleton, R 4 represents a hydrocarbon group having 2 carbon atoms, R 2 and R 3 Each independently represents a hydrogen atom, R 5 The number average molecular weight (chromatographic method, polystyrene conversion) of the component (a1) was 11100, and the viscosity (25° C.) of the component (a1) was 1550 Pa·s.

[0136] <Preparation of Photocurable Resin Composition>

[0137] Example 1

[0138] 100 parts by mass of the polyisobutylene (a1) having an acryloyloxyethoxyphenyl group as the component (A) of the present invention, 78 parts by mass of isobornyl acrylate (IB-XA, manufactured by Kyoeisha Chemical Co., Ltd.) as the component (B) (b1-1), 9 parts by mass of n-lauryl acrylate (LA, manufactured by Kyoeisha Chemical Co., Ltd.) as the component (b2-1), and 8 parts by mass of 1-phenyl-2-hydroxy-2-methylpropane-1-one (Omnirad 1173, manufactured by IGM Resins BV) as the component (C) were added and mixed at room temperature (25° C.) for 60 minutes using a planetary mixer under light shielding to obtain the photocurable resin composition of Example 1.

[0139] Example 2

[0140] Example 2 was obtained in the same manner as in Example 1 except that (b1-1) was changed to 72 parts by mass and (b2-1) was changed to 16 parts by mass.

[0141] Example 3

[0142] Example 3 was obtained in the same manner as in Example 1 except that (b1-1) was changed to 66 parts by mass and (b2-1) was changed to 22 parts by mass.

[0143] Example 4

[0144] Example 4 was obtained in the same manner as in Example 1 except that (b1-1) was changed to 44 parts by mass and (b2-1) was changed to 44 parts by mass.

[0145] Example 5

[0146] Example 5 was obtained in the same manner as in Example 3 except that dicyclopentanyl acrylate (FA-513AS, manufactured by Showa Denko Materials Co., Ltd.) was used as (b1-2) in place of (b1-1).

[0147] Example 6

[0148] Example 6 was obtained in the same manner as in Example 3 except that 4-tert-butylcyclohexyl acrylate (TBCHA, manufactured by KJ Chemicals Co., Ltd.) was used as (b1-3) instead of (b1-1).

[0149] Example 7

[0150] Example 7 was obtained in the same manner as in Example 3 except that isostearyl acrylate (ISTA, manufactured by Osaka Organic Chemical Industry Co., Ltd.) was used as (b2-2) in place of (b2-1).

[0151] Comparative Example 1

[0152] Comparative Example 1 was obtained by carrying out the same procedure as in Example 1 except that (b1-1) was changed to 88 parts by mass and (b2-1) was removed.

[0153] Comparative Example 2

[0154] Comparative Example 2 was obtained in the same manner as in Example 1 except that (b1-1) was removed and (b2-1) was changed to 88 parts by mass.

[0155] Comparative Example 3

[0156] Comparative Example 3 was obtained in the same manner as in Example 3 except that isobornyl methacrylate was used instead of (b1-1).

[0157] Comparative Example 4

[0158] Comparative Example 4 was obtained in the same manner as in Comparative Example 3 except that n-lauryl methacrylate was used instead of (b2-1).

[0159] Comparative Example 5

[0160] Comparative Example 5 was obtained in the same manner as in Example 3 except that phenoxyethyl acrylate was used instead of (b1-1).

[0161] The photocurable resin compositions prepared in each of the Examples and Comparative Examples were subjected to the following tests (1) to (4). The results are shown in Table 1 below. The test methods used in the Examples and Comparative Examples in Table 1 are as follows. Note that a composition was considered suitable if it passed all of the following tests (1) to (4).

[0162] (1) Curing degree confirmation test

[0163] Regarding the degree of curing, the reduction rate of acryloyl or methacryloyl groups in the photocurable resin composition before and after light irradiation was measured using FT-IR (Perkin Elmer, Spectrum 100). The reduction rate was determined by measuring the 1635 cm-1 wavelength from the baseline in the FT-IR spectrum of the photocurable resin composition layer before light irradiation. -1 The absorption peak height (P1) of the CH2=CH2- group and the FT-IR spectrum of the cured product of the photocurable resin composition after light irradiation at 1635 cm from the baseline are compared. -1 The absorption peak height (P2) of the photocurable resin composition is substituted into the following formula (1) to obtain the absorption peak height (P2). At this time, the light irradiation is carried out by applying the photocurable resin composition to a thickness of 50 μm with a cumulative light intensity of 20 kJ / m 2 The results are shown in Table 1. A degree of cure of 75% or more was considered acceptable, with a degree of cure of 77% or more being more preferred, and 80% or more being particularly preferred.

[0164] Curing degree (%) = ((P1-P2) / P1) × 100 (1)

[0165] (2) Determination of hardness

[0166] The thickness of the photocurable resin composition was set to 1 mm, and the cumulative light intensity was 45 kJ / m 2 The ultraviolet rays are applied to cure the sample to produce a sheet-like solidified product. The pressure surface of the A-type hardness tester (hardness tester) is kept parallel to the test piece (a test piece in which 6 sheets of solidified products are overlapped and set to a thickness of 6 mm), and is pressed with a force of 10 N to make the pressure surface fit tightly to the sample. The maximum value is read during the measurement and is set as the "hardness". The results are shown in Table 1. The details are in accordance with JIS K6253 (2012). It should be noted that a hardness of 3 to 95 is considered qualified, and 5 to 90 is more preferred.

[0167] (3) Tensile strength measurement

[0168] The thickness of the photocurable resin composition was set to 1 mm, and the cumulative light intensity was 45 kJ / m 2 The ultraviolet rays are used to cure the sheet-like cured product. A test piece is punched out using a No. 3 dumbbell. Both ends of the test piece are fixed to the chuck in such a way that the long axis of the test piece and the center of the chuck are aligned. The test piece is stretched at a tensile speed of 500 mm / min to measure the maximum load. The strength at this maximum load is defined as "tensile strength (MPa)". The results are shown in Table 1. The details are in accordance with JISK 6251 (2010). It should be noted that from the perspective of high strength in the present invention, a tensile strength of 1.2 MPa or more is qualified, and more preferably 1.7 MPa or more.

[0169] (4) Determination of elongation of cured product

[0170] The thickness of the photocurable resin composition was set to 1 mm, and the cumulative light intensity was 45 kJ / m 2 The cured product was cured by ultraviolet light to produce a sheet. A test piece was punched out using a No. 3 dumbbell and lines were marked on the test piece at 20 mm intervals.

[0171] Fix it to the chuck in the same manner as for the determination of tensile strength, and stretch it at a tensile speed of 500 mm / min until the test piece is cut. During the measurement, the test piece stretches and the spacing between the markings becomes wider, so the spacing between the markings is measured with a vernier caliper before the test piece is cut. The ratio of elongation based on the initial spacing between the markings is set as "elongation (%)". Evaluation is performed based on the following benchmarks, and the results are shown in Table 1. It should be noted that from the viewpoint of high tensile properties, an elongation of 310% or more is considered qualified, and more preferably 350% or more.

[0172]

Table 1

[0173]

[0174] From Examples 1 to 7 in Table 1, it is understood that the present invention can provide a photocurable resin composition having a high degree of curing after light irradiation while maintaining high tensile strength and high strength properties of the cured product.

[0175] In addition, Comparative Example 1 in Table 1 is a photocurable resin composition (b2-1) that does not contain the (B) component of the present invention, and the result is poor in that it is not a high-strength cured product. In addition, Comparative Example 2 is a photocurable resin composition (b1-1) that does not contain the (B) component of the present invention, and the result is poor in that it is not a high-strength, high-strength cured product. In addition, Comparative Example 3 is a photocurable resin composition using a methacrylate monomer having an alicyclic hydrocarbon group as the (b1) component that is not the (B) component of the present invention, and the result is poor in curing degree. Comparative Example 4 is a photocurable resin composition using a methacrylate monomer having an alicyclic hydrocarbon group as the (b1) component that is not the (B) component of the present invention and using a methacrylate monomer having a linear or branched alkyl group that is not the (b2) component, and the result is poor in curing degree. Comparative Example 5 is a photocurable resin composition using component (b1) other than component (B) of the present invention, an acrylate monomer having an aromatic ring. This composition was incompatible with component (A) of the present invention and separated, and could not be tested.

[0176] Furthermore, (5) an adhesive strength test to PEN and (6) a viscosity measurement were performed. The results are shown in Table 2.

[0177] (5) Adhesion test on PEN

[0178] The photocurable resin compositions of Examples 1 to 7 and Comparative Examples 1 to 5 were applied to a PEN test piece having a width of 25 mm × a length of 100 mm × a thickness of 1.6 mm. After that, the same PEN test piece having a width of 25 mm × a length of 10 mm was bonded and fixed, and irradiated with a cumulative light dose of 45 kJ / m 2 The photocurable resin composition was cured by ultraviolet light to prepare a test piece. The two ends of the test piece were fixed and stretched at a tensile speed of 10 mm / min, and the strength at the maximum load measured was set as the adhesion to PEN (MPa). The results are shown in Table 2. It should be noted that in the present invention, from the viewpoint of excellent adhesion to the PEN used in the frame, the adhesion is considered to be qualified when it is 0.8 MPa or more, and more preferably 1.0 MPa or more. It should be noted that the results of Comparative Examples 3 and 4 in Table 2 are that uncured occurred, which means that the test could not be carried out because curing was not carried out. Comparative Example 5 could not be tested due to incompatibility. It should be noted that the aforementioned PEN uses PEN that makes the component translucent.

[0179] (6) Viscosity measurement

[0180] The viscosity (Pa·s) of each photocurable resin composition was measured using a HAAKE MARS3 rheometer manufactured by Thermo Fisher Scientific Co., Ltd. under the following measurement conditions. In the present invention, a viscosity of 50 Pa·s or less is considered acceptable from the perspective of excellent screen printability and adhesion to polymer electrolyte membranes, more preferably 20 Pa·s or less, and particularly preferably 10 Pa·s or less. Comparative Example 5 could not be tested due to incompatibility.

[0181] Measurement conditions

[0182] Shear rate 10(1 / s)

[0183] Temperature 25℃.

[0184]

Table 2

[0185]

[0186] According to Examples 1 to 7 in Table 2, it can be seen that the present invention has excellent adhesion to PEN used in the frame and has low viscosity. In addition, in the photocurable resin composition (b2-1) of Comparative Example 1, which does not contain the (B) component of the present invention, there is no problem with adhesion to PEN, but in the photocurable resin composition of Comparative Example 2, which does not contain (b1-1), the adhesion to PEN is poor. In addition, Comparative Example 3 is a photocurable resin composition using a methacrylate monomer having an alicyclic hydrocarbon group as the component (b1) which is not the (B) component of the present invention, and it is uncured. Comparative Example 4 is a photocurable resin composition using a methacrylate monomer having an alicyclic hydrocarbon group as the component (b1) which is not the (B) component of the present invention and a methacrylate monomer having a linear or branched alkyl group which is not the (b2) component, and the result is that it is uncured. Comparative Example 5 is a photocurable resin composition using an acrylate monomer having an aromatic ring as component (b1) other than component (B) of the present invention. This composition was incompatible with component (A) of the present invention and separated, so it could not be tested.

[0187] Furthermore, tests were conducted on (7) moisture permeability (water vapor barrier properties) and (8) hydrogen gas barrier properties.

[0188] (7) Moisture permeability (water vapor barrier)

[0189] The photocurable resin composition of Example 2 was poured into a frame of 200 mm × 200 mm × 1.0 mm. Then, the photocurable resin composition was poured into a frame of 200 mm × 200 mm × 1.0 mm. The composition was then irradiated with an ultraviolet ray machine at a cumulative light intensity of 45 kJ / m 2The ultraviolet rays were irradiated for 20 seconds to produce a sheet-like solidified product with a thickness of 1.0 mm. 5 g of calcium chloride (anhydrous) was placed in an aluminum cup with an opening of 30 mm in diameter and placed in the cup in such a manner as to cover the solidified product. After measuring the "initial total weight" (g), the sample was placed in a constant temperature and humidity chamber maintained at an ambient temperature of 40°C and a relative humidity of 95% for 24 hours, and the "total weight after placement" (g) was measured. The moisture permeability (g / m 2 · 24h), and evaluated based on the following evaluation criteria. The results are shown in Table 3. The detailed test method is in accordance with JIS Z 0208. It should be noted that when used as a curable sealant for fuel cells, the moisture permeability is preferably less than 10g / m 2 ·24h.

[0190] [Evaluation Criteria]

[0191] Qualified: moisture permeability less than 10g / m 2 24 hours,

[0192] Unqualified: moisture permeability is 10g / m 2 ·More than 24h.

[0193] (8) Hydrogen barrier test

[0194] The photocurable resin composition of Example 2 was used and a UV irradiation machine was used to give a cumulative light dose of 45 kJ / m 2 The sheet-like cured product with a thickness of 1.0 mm was prepared by irradiating the sheet-like cured product with ultraviolet rays for 20 seconds. Next, the hydrogen barrier properties were measured using the obtained sheet-like cured product in accordance with JIS K7126-1:2006 (Plastics-Films and sheets-Gas permeability test methods-Part 1: Pressure difference method). It should be noted that the test type is a pressure sensor method, and the measurement is carried out under the conditions of 23°C and 100 kPa of the test gas (hydrogen) on the high pressure side, and the evaluation is based on the following evaluation criteria. The results are shown in Table 3. It should be noted that when used as a photocurable sealant for fuel cells, the hydrogen barrier properties are preferably less than 1×10 -15 mol·m / m 2 ·s·Pa.

[0195] [Evaluation Criteria]

[0196] Qualified: less than 1×10 -15 mol·m / m 2 ·s·Pa,

[0197] Unqualified: 1×10 -15 mol·m / m 2 ·s·Pa or above.

[0198]

Table 3

[0199] (7) Water vapor barrier test (8) Hydrogen barrier test Example 2 qualified qualified

[0200] According to Example 2 in Table 3, it can be seen that the present invention has low moisture permeability, excellent hydrogen barrier properties, and good sealing properties.

[0201] Industrial Applicability

[0202] The present invention was developed in light of the above-mentioned circumstances. Because it provides a photocurable resin composition that maintains high tensile strength and high strength properties in a cured product and exhibits a high degree of cure after light irradiation, it can be used in various sealing applications. It is particularly effective as a curable sealant for fuel cells, thus having industrial value.

[0203] This application is based on Japanese Patent Application No. 2020-104162 filed on June 17, 2020, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A photocurable resin composition, characterized in that It contains the following components (A) to (C), Component (A): a polyisobutylene resin containing one or more (meth)acryloyl groups and -[CH2C(CH3)2]- units; Component (B): any one of the following acrylate monomers (1) to (4), (1) isobornyl acrylate as component (b1) and n-lauryl acrylate as component (b2), (2) dicyclopentanyl acrylate as component (b1) and n-lauryl acrylate as component (b2), (3) 4-tert-butylcyclohexyl acrylate as component (b1) and n-lauryl acrylate as component (b2), (4) isobornyl acrylate as component (b1) and isostearyl acrylate as component (b2); Component (C): photoradical polymerization initiator, However, the component (b1) is contained in an amount of 66 to 95 parts by mass and the component (b2) is contained in an amount of 3 to 22 parts by mass based on 100 parts by mass of the component (A).

2. The photocurable resin composition according to claim 1, wherein The component (A) is a polyisobutylene resin represented by the following general formula (1): 【Chemical Formula 1】 In the general formula (1), R 1 represents a monovalent or divalent to hexavalent aromatic hydrocarbon group, or a monovalent or divalent to hexavalent aliphatic hydrocarbon group, PIB represents a polyisobutylene skeleton containing the -[CH2C(CH3)2]- unit, R 4 represents a divalent hydrocarbon group having 2 to 6 carbon atoms, R 2 and R 3 Each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R 5 represents a hydrogen atom or a methyl group, and n is an integer of 1 to 6. 3 . A curable sealant for a fuel cell, comprising the photocurable resin composition according to claim 1 .

4. The curable sealant for fuel cell according to claim 3, wherein The fuel cell curable sealant is a fuel cell curable sealant used around one or more components selected from the group consisting of a separator, a frame, a polymer electrolyte membrane, a fuel electrode, an air electrode, and an electrolyte membrane electrode assembly, which are components of the fuel cell.

5. The curable sealant for fuel cell according to claim 4, wherein The curable sealant for a fuel cell is a sealant between adjacent separators in a fuel cell, or a sealant between a frame of a fuel cell and a polymer electrolyte membrane or an electrolyte membrane electrode assembly.

6. The curable sealant for fuel cell according to claim 3, wherein The curable sealant for fuel cells is a curable sealant for solid polymer fuel cells. 7 . A cured product obtained by irradiating the photocurable resin composition according to claim 1 or the curable sealant for a fuel cell according to claim 3 with light.

8. A fuel cell, wherein: A seal between adjacent separators in a fuel cell, or a seal between a frame of a fuel cell and a polymer electrolyte membrane or a membrane electrode assembly comprises the cured product according to claim 7 .

9. The fuel cell according to claim 8, wherein The fuel cell is a solid polymer fuel cell.

10. A sealing method, comprising: sealing at least a portion between two flanges. At least one of the flanges is a flange that can transmit active energy rays, The method comprises: a step of applying the photocurable resin composition according to claim 1 or 2 to a surface of a flange; a step of bonding the flange coated with the photocurable resin composition to another flange via the photocurable resin composition; and The step of irradiating the photocurable resin composition with active energy rays through the flange that is permeable to the active energy rays, curing the photocurable resin composition, and sealing at least a portion between the two flanges.

11. A sealing method for sealing at least a portion between two flanges. The method comprises: a step of applying the photocurable resin composition according to claim 1 or 2 to a surface of a flange; irradiating the photocurable resin composition with active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition on the one flange; and The step of placing the other flange on the gasket, and press-bonding the one flange and the other flange with the gasket interposed therebetween to seal at least a portion between the two flanges.

12. A sealing method for sealing at least a portion between two flanges. The method comprises: a step of arranging a gasket forming mold on one flange; a step of injecting the photocurable resin composition according to claim 1 or 2 into at least a portion of the gap between the gasket forming mold and the one flange; irradiating the photocurable resin composition with active energy rays to cure the photocurable resin composition, thereby forming a gasket composed of a cured product of the photocurable resin composition on the one flange; a step of removing the mold from the one flange; and The step of placing the other flange on the gasket, and press-bonding the one flange and the other flange with the gasket interposed therebetween to seal at least a portion between the two flanges.

Images