Gasket member for polymer electrolyte fuel cell, electrode-electrolyte membrane laminate with gasket member, and polymer electrolyte fuel cell

Abstract

Provided is a gasket member for a polymer electrolyte fuel cell that has high adhesion between a heat-resistant substrate layer and an adhesive layer, and has excellent hydrolysis resistance in a high-temperature environment. [Solution] The laminate is made up of at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 160°C or higher, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin.

Description

[Technical Field]

[0001] The present disclosure relates to a gasket member for a polymer electrolyte fuel cell, an electrode-electrolyte membrane laminate with a gasket member, and a polymer electrolyte fuel cell. [Background technology]

[0002] Fuel cells are cells that have electrodes on both sides of an electrolyte and generate electricity through an electrochemical reaction between hydrogen and oxygen, producing only water during the process. Unlike conventional internal combustion engines, fuel cells do not emit environmentally harmful gases such as carbon dioxide, and are therefore expected to become widespread as next-generation clean energy systems. Among these, polymer electrolyte fuel cells in particular have a relatively low operating temperature, low electrolyte resistance, and the use of highly active catalysts allows them to produce high output even in a small size, leading to expectations for early practical application in household cogeneration systems and other applications.

[0003] This polymer electrolyte fuel cell is manufactured by first preparing a proton-conductive polymer electrolyte membrane, then forming an anode catalyst layer on one side of this electrolyte membrane and a cathode catalyst layer on the other side to produce a catalyst layer-electrolyte membrane laminate, then forming a gas diffusion layer on each catalyst layer to produce an electrode-electrolyte membrane laminate, and finally installing a gasket and a separator on this electrode-electrolyte membrane laminate to complete the polymer electrolyte fuel cell (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-218876 Summary of the Invention [Problem to be solved by the invention]

[0005] Fuel cells operate in a humidified atmosphere to improve the proton conductivity of the electrolyte membrane, and because water is generated during the power generation reaction, the components that make up the fuel cell must also have high hydrolysis resistance. Furthermore, since the power density can be improved by increasing the operating temperature of the fuel cell, use in high-temperature environments (e.g., above 100°C) is required from the perspective of miniaturizing fuel cells.

[0006] However, among the components constituting a fuel cell, the gasket member does not necessarily have sufficient hydrolysis resistance in a high-temperature environment. When a fuel cell is used in a high-temperature environment, if the gasket member does not have sufficient hydrolysis resistance in the high-temperature environment, the gasket member may be hydrolyzed, causing problems such as fuel leakage.

[0007] Under these circumstances, a main object of the present disclosure is to provide a gasket member for a polymer electrolyte fuel cell that has excellent resistance to hydrolysis in a high-temperature environment. [Means for solving the problem]

[0008] The inventors of the present disclosure have conducted extensive research to solve the above-mentioned problems, and as a result, have found that a gasket member composed of a laminate including at least a base material layer and adhesive layers disposed on both sides of the base material layer, wherein the base material layer contains a resin having a glass transition temperature of 160°C or higher and the adhesive layers contain at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, has high adhesion between the heat-resistant base material layer and the adhesive layers, and has excellent hydrolysis resistance in high-temperature environments, and therefore can be suitably used as a gasket member for a polymer electrolyte fuel cell.

[0009] The present disclosure has been completed based on such novel findings and through further investigations. That is, the present disclosure provides the inventions of the following aspects. The laminate is made up of at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 160°C or higher, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a gasket member for a polymer electrolyte fuel cell that has high adhesion between a substrate layer and an adhesive layer and has excellent hydrolysis resistance in a high-temperature environment. Furthermore, according to the present disclosure, it is also possible to provide an electrode-electrolyte membrane laminate with a gasket member and a polymer electrolyte fuel cell that use the gasket member. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing an example of a cross-sectional structure of a gasket member for a polymer electrolyte fuel cell according to the present disclosure. [Figure 2] 1 is a schematic diagram showing an example of a cross-sectional structure of a gasket member for a polymer electrolyte fuel cell according to the present disclosure. [Figure 3] 1 is a schematic plan view of a gasket member for a polymer electrolyte fuel cell according to the present disclosure; [Figure 4] 1 is a schematic diagram showing an example of a cross-sectional structure of an electrode-electrolyte membrane laminate with a gasket member according to the present disclosure. [Figure 5] 1 is an example of a schematic plan view of an electrode-electrolyte membrane stack with a gasket member according to the present disclosure. [Figure 6] 1 is a schematic diagram showing an example of a cross-sectional structure of a polymer electrolyte fuel cell according to the present disclosure. [Figure 7] 1 is a schematic diagram showing an example of a cross-sectional structure of a polymer electrolyte fuel cell according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] The gasket member for a polymer electrolyte fuel cell of the present disclosure is composed of a laminate including at least a substrate layer and adhesive layers disposed on both sides of the substrate layer, wherein the substrate layer contains a resin having a glass transition temperature of 160°C or higher, and the adhesive layers contain at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin. The gasket member for a polymer electrolyte fuel cell of the present disclosure has high adhesion between the substrate layer, which has excellent heat resistance, and the adhesive layers, and has excellent hydrolysis resistance in high-temperature environments.

[0013] As described below, the gasket member for a polymer electrolyte fuel cell according to the present disclosure is a gasket member that is disposed between the electrolyte membrane and separator of a polymer electrolyte fuel cell, and can be applied to a wide range of polymer electrolyte fuel cells.

[0014] The gasket member for a polymer electrolyte fuel cell according to the present disclosure will be described in detail below. In this specification, numerical ranges indicated by "to" mean "greater than or equal to" or "less than or equal to." For example, the expression "2 to 15 mm" means 2 mm or greater and 15 mm or less.

[0015] 1.Layer structure and physical properties of gasket components for polymer electrolyte fuel cells A gasket member 10 for a polymer electrolyte fuel cell according to the present disclosure (hereinafter sometimes referred to as gasket member 10) is composed of a laminate including at least a substrate layer 1 and adhesive layers 2 disposed on both sides of the substrate layer 1, as shown in FIG. 1, for example. That is, the gasket member 10 is composed of a laminate in which at least the adhesive layer 2, the substrate layer 1, and the adhesive layer 2 are laminated in this order. The adhesive layers 2 on both sides of the gasket member 10 each constitute the outermost layers of the gasket member 10, with the adhesive layer 2 on one side being disposed on the electrolyte membrane 21 side and the adhesive layer 2 on the other side being disposed on the separator 25 side (see FIG. 6).

[0016] As will be described later, the gasket member 10 is disposed, for example, so as to surround the periphery of the electrode-electrolyte membrane laminate (see the schematic diagrams of the electrode-electrolyte membrane laminate with the gasket member in FIGS. 4 and 5). Therefore, such a gasket member 10 has openings 11 for inserting the catalyst layers 22, 23 and the gas diffusion layer 24 (see FIG. 3).

[0017] As shown in FIG. 2 , the gasket member 10 may include an anchor coat layer 3 on at least one surface of the base material layer 1. For example, when the base material layer 1 is formed of a film, providing the anchor coat layer 3 between the base material layer 1 and the adhesive layer 2 can enhance the adhesion between the base material layer 1 and the adhesive layer 2. That is, the gasket member 10 may be composed of a laminate in which at least the adhesive layer 2, the anchor coat layer 3, the base material layer 1, the anchor coat layer 3, and the adhesive layer 2 are laminated in this order. However, since the gasket member 10 of the present disclosure includes the adhesive layer 2 containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, which have excellent adhesion to the base material layer 1, as described below, the base material layer 1 and the adhesive layer 2 may be in direct contact with each other without providing the anchor coat layer 3.

[0018] As described below, the adhesive layer may have a laminated structure of two or more layers including a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin, or a laminated structure of three or more layers including a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin.

[0019] The thickness (total thickness) of the laminate constituting the gasket member 10 is adjusted depending on the size of the polymer electrolyte fuel cell and is not particularly limited, and may be, for example, about 300 μm or less, about 200 μm or less, about 100 μm or less, or about 50 μm or less, or about 30 μm or more, about 100 μm or more, about 200 μm or more, or about 250 μm or more. Preferred ranges for the thickness (total thickness) of the laminate constituting the gasket member 10 include about 30 to 300 μm, about 30 to 200 μm, about 30 to 100 μm, about 30 to 50 μm, about 100 to 300 μm, about 100 to 200 μm, about 200 to 300 μm, and about 250 to 300 μm.

[0020] For example, as shown in FIG. 7, when one gasket member 10 is used to surround the periphery of an electrode-electrolyte membrane stack, the thickness (total thickness) of the stack constituting the gasket member 10 is preferably not more than about 400 μm, more preferably not more than about 300 μm, and also preferably not less than about 30 μm, more preferably not less than about 50 μm, even more preferably more than 50 μm, and even more preferably not less than about 100 μm. Preferred ranges include about 30 to 400 μm, about 30 to 30 μm, about 50 to 400 μm, about 50 to 300 μm, more than 50 μm but not more than about 400 μm, more than 50 μm but not more than about 300 μm, about 100 to 400 μm, and about 100 to 300 μm. In this case, the thickness of base layer 1 is preferably about 300 μm or less, more preferably about 200 μm or less, and preferably about 20 μm or more, more preferably about 30 μm or more, and even more preferably 50 μm or more, with preferred ranges being about 20 to 300 μm, about 20 to 200 μm, about 30 to 300 μm, about 30 to 200 μm, about 50 to 300 μm, and about 50 to 200 μm. The thickness of adhesive layer 2 is preferably about 200 μm or less, more preferably about 100 μm or less, and preferably about 10 μm or more, more preferably about 30 μm or more, with preferred ranges being about 10 to 200 μm, about 10 to 100 μm, about 30 to 200 μm, and about 30 to 100 μm.

[0021] 6, when two gasket members 10 are arranged to surround the periphery of an electrode-electrolyte membrane stack, the thickness (total thickness) of the stack constituting each gasket member 10 is preferably about 200 μm or less, more preferably about 150 μm or less, and preferably about 25 μm or more, more preferably about 50 μm or more, with preferred ranges of about 25 to 200 μm, about 25 to 150 μm, about 50 to 200 μm, and about 50 to 150 μm. In this case, the thickness of the base layer 1 is preferably about 200 μm or less, more preferably about 150 μm or less, and preferably about 10 μm or more, more preferably about 15 μm or more, with preferred ranges of about 10 to 200 μm, about 10 to 150 μm, about 15 to 200 μm, and about 15 to 150 μm. The thickness of the adhesive layer 2 is preferably about 100 μm or less, more preferably about 50 μm or less, and is preferably about 3 μm or more, more preferably about 15 μm or more, with preferred ranges including about 3 to 100 μm, about 3 to 50 μm, about 15 to 100 μm, and about 15 to 50 μm.

[0022] In the present disclosure, whether to use one gasket member 10 or two gasket members 10 may be selected as appropriate depending on the specifications of the polymer electrolyte fuel cell 30. The total thickness of the gasket member 10 and the thickness of each layer may also be selected as appropriate depending on the thickness of the polymer electrolyte fuel cell 30.

[0023] In the gasket member 10, the ratio of the total thickness of the base material layer 1, adhesive layer 2, and optional anchor coat layer 3 to the thickness (total thickness) of the laminate constituting the gasket member 10 is preferably 90% or more, more preferably 95% or more, even more preferably 98% or more, or even 100%. Specifically, when the gasket member 10 of the present disclosure includes the base material layer 1 and adhesive layer 2, the ratio of the total thickness of these layers to the thickness (total thickness) of the laminate constituting the gasket member 10 is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. Furthermore, when the gasket member 10 of the present disclosure is a laminate including the base material layer 1, adhesive layer 2, and anchor coat layer 3, the ratio of the total thickness of these layers to the thickness (total thickness) of the laminate constituting the gasket member 10 is, for example, 80% or more, preferably 90% or more, more preferably 95% or more, even more preferably 98% or more, or even 100%.

[0024] The laminate constituting the gasket member 10 of the present disclosure preferably has a breaking elongation retention of 60% or more after being left to stand in water at 120°C (in a heat-resistant and pressure-resistant container) for 300 hours. This allows the laminate to exhibit excellent hydrolysis resistance in high-temperature environments. The breaking elongation retention of the gasket member 10 is measured as follows.

[0025] <Method for measuring breaking elongation retention> The breaking elongation retention is measured as follows. Specifically, after immersing the sample in water at 120°C and leaving it to stand for 300 hours, the breaking elongation of the sample is measured, and the measured value is divided by the breaking elongation before the durability test (initial breaking elongation) to determine the breaking elongation retention. The breaking elongation is measured by cutting the film into strips with a width (TD) of 15 mm and a length (MD) of 50 mm, and pulling it using a tensile tester at a pulling speed of 200 mm / min and a gauge length of 20 mm until it breaks. The test environment is 23°C, and the average value of three measurements is used. Breaking elongation retention rate (%) = Breaking elongation after durability test ÷ Breaking elongation before durability test (initial breaking elongation) × 100

[0026] One method for confirming the MD of a gasket member is to observe a cross section of the gasket member (e.g., a cross section of the first adhesive layer, base material, or second adhesive layer) using an electron microscope to confirm the sea-island structure. In this method, the direction parallel to the cross section in which the average diameter of the island shapes in the direction perpendicular to the thickness direction of the gasket member is largest can be determined as the MD. Specifically, the sea-island structure is confirmed by observing, using an electron microscope, a cross section of the gasket member in the longitudinal direction and each cross section at an angle of 10 degrees from the direction parallel to the longitudinal cross section up to the direction perpendicular to the longitudinal cross section (a total of 10 cross sections). Next, the shape of each individual island in each cross section is observed. For each island shape, the linear distance connecting the leftmost end in the direction perpendicular to the thickness direction of the gasket member to the rightmost end in the vertical direction is defined as the diameter y. For each cross section, the average of the diameters y of the top 20 island shapes in descending order of diameter y is calculated. The direction parallel to the cross section in which the average diameter y of the island shapes is largest is determined as the MD.

[0027] In order to exhibit excellent properties due to hydrolysis resistance in high-temperature environments, the breaking elongation retention rate of the laminate constituting the gasket member 10 is 60% or more, preferably 65% ​​or more, more preferably 70% or more, even more preferably 75% or more, even more preferably 80% or more, and particularly preferably 85% or more.

[0028] An effective method for increasing the breaking elongation retention rate of the laminate constituting the gasket member 10 to 60% or more is, for example, to use a resin with a particularly high glass transition temperature (Tg) as the material for forming the base layer 1.

[0029] From the viewpoint of exhibiting excellent properties due to hydrolysis resistance in high-temperature environments, the hot shrinkage rate of the laminate constituting the gasket member 10 when left standing in an environment at a temperature of 150°C for 30 minutes is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less. From the same viewpoint, the hot shrinkage rate of the laminate constituting the gasket member 10 when left standing in an environment at a temperature of 180°C for 30 minutes is preferably 30% or less, more preferably 20% or less, even more preferably 10% or less, even more preferably 3% or less, even more preferably 1% or less, and even more preferably 0.5% or less. The hot shrinkage rate of the gasket member 10 is measured as follows.

[0030] <Method for measuring hot shrinkage at 150℃ or 180℃> The hot shrinkage rate was determined by cutting a gasket member into a test piece measuring 10 cm in length (MD) x 10 cm in width (TD), heating it in an oven at 150°C or 180°C for 30 minutes, determining the dimensional change rate of the test piece in the length and width directions (two perpendicular directions) before and after heating based on the following formula (I), and calculating the average of the absolute values ​​of the dimensional change rate in the two directions. Hot shrinkage rate (%) = {(XY) / X} × 100 (I) [X: Dimensions before heating in the oven, Y: Dimensions after heating in the oven]

[0031] 2. Layers forming a gasket member for a polymer electrolyte fuel cell [Base material layer 1] In the present disclosure, the base material layer 1 is a layer provided for the purpose of, for example, functioning as a base material of the gasket member 10. The base material layer 1 is located between two adhesive layers 2.

[0032] In the present disclosure, the glass transition temperature (Tg) of the resin forming the base layer 1 is 160° C. or higher, preferably about 165° C. or higher, more preferably about 170° C. or higher, and even more preferably about 175° C. or higher. The upper limit of the glass transition temperature (Tg) is, for example, about 450° C. or lower. The glass transition temperature (Tg) refers to the baseline displacement point of a differential scanning calorimeter (DSC) curve measured by DSC.

[0033] The substrate layer 1 is preferably formed from a material that satisfies the above-mentioned glass transition temperature and has excellent hydrolysis resistance, and preferably contains, for example, polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethyltene, polyphenylene oxide, polyphenylene sulfide, fluororesin, metal, etc. When these materials are used to form the substrate layer 1, the substrate layer 1 may contain one type of these materials or two or more types of these materials.

[0034] Specific examples of polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene-α-olefin copolymers; polypropylenes such as homopolypropylene, polypropylene block copolymers (e.g., propylene and ethylene block copolymers), and polypropylene random copolymers (e.g., propylene and ethylene random copolymers); propylene-α-olefin copolymers; and ethylene-butene-propylene terpolymers. Among these, polypropylene is preferred. When the polyolefin resin is a copolymer, it may be a block copolymer or a random copolymer. Furthermore, the polyolefin resin may be an acid-modified polyolefin. When the base layer 1 contains a polyolefin, the polyolefin contained in the base layer 1 may be one type or two or more types.

[0035] Acid-modified polyolefins are polymers modified by block polymerization or graft polymerization of polyolefins with an acid component. Examples of acid-modified polyolefins include the aforementioned polyolefins, copolymers of the aforementioned polyolefins with polar molecules such as acrylic acid or methacrylic acid, and crosslinked polyolefins. Examples of acid components used for acid modification include carboxylic acids or their anhydrides, such as maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride. Preferred acid-modified polyolefins include polyolefins modified with carboxylic acids or their anhydrides, polypropylenes modified with carboxylic acids or their anhydrides, maleic anhydride-modified polyolefins, and maleic anhydride-modified polypropylenes. When the base layer 1 contains an acid-modified polyolefin, the base layer 1 may contain only one type of acid-modified polyolefin, or two or more types of acid-modified polyolefins.

[0036] Specific examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and copolymers of nylon 6 and nylon 66; hexamethylenediamine-isophthalic acid-terephthalic acid copolymer polyamides such as nylon 6I, nylon 6T, nylon 6IT, and nylon 6I6T (where I represents isophthalic acid and T represents terephthalic acid), which contain structural units derived from terephthalic acid and / or isophthalic acid; and aromatic polyamides such as polyamide MXD6 (polymetaxylylene adipamide); alicyclic polyamides such as polyamide PACM6 (polybis(4-aminocyclohexyl)methane adipamide); polyamides copolymerized with a lactam component or an isocyanate component such as 4,4'-diphenylmethane diisocyanate; polyesteramide copolymers and polyetheresteramide copolymers, which are copolymers of copolymerized polyamides with polyesters or polyalkylene ether glycols; and copolymers of these polyamides. When the base layer 1 contains polyamide, the base layer 1 may contain only one type of polyamide, or two or more types of polyamide.

[0037] As the polyamide, those having α crystals are particularly preferred, and specific examples include aliphatic polyamides such as nylon 6, nylon 66, nylon 46, and copolymers of nylon 6 and nylon 66.

[0038] Examples of metals include aluminum alloys, copper, zinc, titanium, and stainless steel.

[0039] In the present disclosure, from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, the base layer 1 preferably contains polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, or polyolefin, more preferably polysulfone, polyethersulfone, or polyphenylsulfone, and even more preferably polyphenylsulfone. The base layer 1 is preferably formed from at least one of these resins, and particularly preferably from polyphenylsulfone. As described below, polysulfone-based resins such as polysulfone, polyethersulfone, and polyphenylsulfone have excellent adhesion to the adhesive layer 2 containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin.

[0040] The substrate layer 1 may be in the form of a film or a nonwoven fabric. For example, when the substrate layer 1 is in the form of a film, the substrate layer 1 can be suitably formed from a film of the resin described above. Furthermore, when the substrate layer 1 is in the form of a nonwoven fabric, the substrate layer 1 can be suitably formed from a nonwoven fabric of the resin described above. When the substrate layer 1 is in the form of a nonwoven fabric, the adhesive layer 2 can be impregnated into the gaps in the substrate layer 1, which is a nonwoven fabric, thereby increasing the physical adhesion between the substrate layer 1 and the adhesive layer 2.

[0041] The base layer 1 may be a single layer or may be composed of two or more layers. When the base layer 1 is composed of two or more layers, the materials and thicknesses of the layers may be the same or different.

[0042] In addition, additives such as fillers, flame retardants, antiblocking agents, antioxidants, light stabilizers, tackifiers, and antistatic agents may be present on at least one of the surface and interior of the base material layer 1. Specific examples of additives include metal oxide particles such as alumina, silica, and titania. Only one type of additive may be used, or two or more types may be mixed and used.

[0043] In the present disclosure, the thickness of the substrate layer 1 is adjusted appropriately depending on the size of the polymer electrolyte fuel cell, etc., but from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, it is preferably about 20 μm or more, more preferably about 40 μm or more, even more preferably about 50 μm or more, and even more preferably about 100 μm or more, and is preferably about 200 μm or less, more preferably about 150 μm or less, and even more preferably about 100 μm or less. Preferred ranges for the thickness of the substrate layer 1 include about 20 to 200 μm, about 20 to 150 μm, about 20 to 100 μm, about 40 to 200 μm, about 40 to 150 μm, about 40 to 100 μm, about 100 to 200 μm, and about 100 to 150 μm.

[0044] When the substrate layer 1 is in the form of a nonwoven fabric, the basis weight of the substrate layer 1 is adjusted appropriately depending on the size of the polymer electrolyte fuel cell, etc., but from the viewpoint of suitably increasing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, it is preferably about 5 g / m 2 More preferably, about 10 g / m 2 More preferably, about 15 g / m 2 or more, and preferably about 50 g / m 2 or less, more preferably about 40 g / m 2 or less, more preferably about 30 g / m 2 When the base material layer 1 is in the form of a nonwoven fabric, the preferred range of the basis weight of the base material layer 1 is 5 to 50 g / m 2 degree, 5~40g / m 2 degree, 5~30g / m 2 degree, 10~50g / m 2 degree, 10~40g / m 2 degree, 10~30g / m 2degree, 15~50g / m 2 degree, 15~40g / m 2 degree, 15~30g / m 2 The degree of

[0045] [Adhesive layer 2] In the gasket member 10, adhesive layers 2 are disposed on both sides of the base layer 1. The adhesive layers 2 on both sides of the gasket member 10 constitute the outermost layers of the gasket member 10, with the adhesive layer 2 on one side disposed on the electrolyte membrane 21 side and the adhesive layer 2 on the other side disposed on the separator 25 side (see FIG. 6). The adhesive layer 2 on the electrolyte membrane 21 side and the adhesive layer 2 on the separator 25 side may be made of the same material, have different thicknesses, or may be different. Additives such as fillers, flame retardants, antiblocking agents, antioxidants, light stabilizers, tackifiers, and antistatic agents may be present on at least one of the surface and interior of the adhesive layer 2. Specific examples of additives include metal oxide particles such as alumina, silica, and titania. One type of additive may be used alone, or two or more types may be mixed together.

[0046] The adhesive layer 2 contains at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin. The imine-modified polyolefin and the carbodiimide-modified polyolefin each have excellent adhesion to the resin having a high glass transition temperature (160°C or higher) used in the base layer 1, and therefore excellent adhesion between the base layer 1 and the adhesive layer 2. Therefore, the gasket member 10 of the present disclosure exhibits excellent hydrolysis resistance in high-temperature environments. Since the imine-modified polyolefin and the carbodiimide-modified polyolefin have excellent adhesion, particularly to polysulfone-based resins such as polysulfone, polyethersulfone, and polyphenylsulfone, it is particularly effective to use a polysulfone-based resin such as polysulfone, polyethersulfone, or polyphenylsulfone for the base layer 1. Furthermore, the imine-modified polyolefin and the carbodiimide-modified polyolefin also have good adhesion to the separator 25 and the electrolyte membrane 21.

[0047] The adhesive layer 2 may have a laminated structure of two or more layers, including, in order from the base layer 1 side, a layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin. Alternatively, the adhesive layer 2 may have a laminated structure of three or more layers, including, in order from the base layer 1 side, a layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin. As described above, imine-modified polyolefin and carbodiimide-modified polyolefin have excellent adhesion to the resin having a high glass transition temperature used in the base layer 1, and acid-modified polyolefin has excellent adhesion to the separator 25 made of metal, so these laminated structures are preferable. Furthermore, by providing a layer containing a polyolefin between the layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin and the layer containing an acid-modified polyolefin, it is possible to suppress acid-base reactions caused by direct contact between the layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin and the layer containing an acid-modified polyolefin. When the adhesive layer 2 comprises a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin, it is preferable that the layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin constitutes the surface on the substrate layer 1 side, and the layer containing an acid-modified polyolefin constitutes the surface on the separator 25 side. Furthermore, in these laminate structures of the adhesive layer 2, it is particularly preferable that the layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, the layer containing a polyolefin, and the layer containing an acid-modified polyolefin are, respectively, a layer formed from at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer formed from a polyolefin, and a layer formed from an acid-modified polyolefin.

[0048] The imine-modified polyolefin is preferably obtained by grafting a polyimine compound having a plurality of imino groups onto a polyolefin in the presence of a radical generator. The imine-modified polyolefin is preferably imine-modified polypropylene from the viewpoint of suitably enhancing hydrolysis resistance in a high-temperature environment.

[0049] The carbodiimide-modified polyolefin is obtained by reacting a polyolefin having a group reactive with a carbodiimide group with a carbodiimide group-containing compound, preferably at 230° C. or higher. Specifically, the carbodiimide-modified polyolefin can be obtained by melt-kneading, such as melt modification, but is not limited to this method. The carbodiimide-modified polyolefin is preferably a carbodiimide-modified polypropylene, from the viewpoint of suitably enhancing hydrolysis resistance in a high-temperature environment.

[0050] Examples of the acid-modified polyolefin and polyolefin are the same as those exemplified for the base layer 1. Among the acid-modified polyolefins, acid-modified polypropylene is preferred. Among the polyolefins, polypropylene is preferred. In the present disclosure, by using an acid-modified polyolefin for the adhesive layer 2, adhesion to the separator 25 is improved, and the hydrolysis resistance of the gasket member 10 in a high-temperature environment can be suitably improved.

[0051] The thickness of the adhesive layer 2 is adjusted appropriately depending on the size of the polymer electrolyte fuel cell, etc., but from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, it is preferably about 10 μm or more, more preferably about 15 μm or more, and even more preferably about 20 μm or more, and is preferably about 100 μm or less, more preferably about 80 μm or less, and even more preferably about 60 μm or less. Preferred ranges for the thickness of the adhesive layer 2 include about 10 to 100 μm, about 10 to 80 μm, about 10 to 60 μm, about 15 to 100 μm, about 15 to 80 μm, about 15 to 60 μm, about 20 to 100 μm, about 20 to 80 μm, and about 20 to 60 μm.

[0052] When the adhesive layer 2 has a laminated structure of two or more layers, the preferred thickness range of the layer containing at least one of the imine-modified polyolefin and the carbodiimide-modified polyolefin is about 5 to 50 μm. The preferred thickness range of the layer containing the acid-modified polyolefin is about 5 to 50 μm. The preferred thickness range of the layer containing the polyolefin is about 5 to 50 μm. The adhesive layers 2 on both sides may have the same composition and thickness or may be different.

[0053] A laminate of a base material layer 1 and adhesive layers 2 on both sides thereof can be produced, for example, by extruding a resin that will form adhesive layer 2 onto both sides of a pre-prepared base material layer 1, or by extruding a resin that will form base material layer 1 and a resin that will form adhesive layer 2. The method for extruding and laminating the resin is not particularly limited, and known methods such as extrusion lamination, T-die lamination, inflation lamination, and thermal lamination can be applied. When providing an anchor coat layer 3 (described below), a resin that will form anchor coat layer 3 or the like can be applied to at least one side of the surface of base material layer 1, and then an adhesive layer can be laminated on top of that.

[0054] [Anchor coat layer 3] The anchor coat layer 3 is a layer that is provided on at least one side of the surface of the base layer 1 as needed, for the purpose of further increasing the adhesiveness between the base layer 1 and the adhesive layer 2.

[0055] As described above, the gasket member 10 of the present disclosure has an adhesive layer 2 containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, which have excellent adhesion to the base layer 1, and therefore the base layer 1 and the adhesive layer 2 may be in direct contact with each other without providing an anchor coat layer 3.

[0056] The material for forming the anchor coat layer 3 is not particularly limited as long as it enhances the adhesion between the base material layer 1 and the adhesive layer 2, but preferred examples include isocyanate-based, polyethyleneimine-based, polyester-based, polyurethane-based, polyvinyl butyral-based, acrylic-based, aminoethylated acrylic polymer-based, styrene / maleic acid copolymer-based, rubber-based, and epoxy-based resins. These resins can be used alone or in combination of two or more.

[0057] The compound having an isocyanate group is not particularly limited, but from the viewpoint of effectively increasing the adhesion between the base layer 1 and the adhesive layer 2, a polyfunctional isocyanate compound is preferably used. The polyfunctional isocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups. Specific examples of polyfunctional isocyanate curing agents include pentane diisocyanate (PDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), m-xylylene diisocyanate (XDI), polymers or nurates thereof, mixtures of these, and copolymers with other polymers. Other examples include adducts, biuret compounds, and isocyanurates. Other examples include triisocyanates such as triphenylmethane-4,4',4"-triisocyanate and tris(p-isocyanatephenyl)thiophosphate. The compound having an isocyanate group used to form the anchor coat layer 3 may be one type or two or more types.

[0058] Examples of polyurethane-based materials include a two-component mixture of a polyester resin and a polyfunctional isocyanate compound, a two-component mixture of a polycarbonate diol and a polyfunctional isocyanate compound, etc. Specific examples of polyurethane-based materials include a two-component mixture of a polyester resin and hexamethylene diisocyanate, a two-component mixture of a polycarbonate diol and polymethylene polyphenyl polyisocyanate, etc.

[0059] The thickness of the anchor coat layer 3 is adjusted appropriately depending on the size of the polymer electrolyte fuel cell, etc., but from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, it is preferably about 0.02 g / m 2 More preferably, 0.05 g / m 2 More preferably, about 0.1 g / m 2 More preferably, about 0.3 g / m 2 More preferably, about 0.5 g / m 2 or more, and preferably about 5 g / m 2 or less, more preferably about 4 g / m 2 or less, more preferably about 3 g / m 2 The preferred range of the thickness of the anchor coat layer 3 is 0.02 to 5 g / m 2 degree, 0.02~4g / m 2 degree, 0.02~3g / m 2 degree, 0.05~5g / m 2 degree, 0.05~4g / m 2 degree, 0.05~3g / m 2 degree, 0.1~5g / m 2 degree, 0.1~4g / m 2 degree, 0.1~3g / m 2 degree, 0.3~5g / m 2 degree, 0.3~4g / m 2 degree, 0.3~3g / m 2 degree, 0.5~5g / m 2 degree, 0.5~4g / m 2 degree, 0.5~3g / m 2 The degree of

[0060] 3. Electrode-electrolyte membrane laminate with gasket member The electrode-electrolyte membrane laminate 20 with a gasket member of the present disclosure is an electrode-electrolyte membrane laminate to which a gasket member 10 of the present disclosure is attached (see FIG. 4). Specifically, the electrode-electrolyte membrane laminate 20 with a gasket member of the present disclosure comprises an electrode-electrolyte membrane laminate in which catalyst layers 22, 23 and a gas diffusion layer 24 are arranged on both sides of an electrolyte membrane 21, and a frame-shaped gasket member 10 arranged to cover the outer periphery of the electrode-electrolyte membrane laminate, the gasket member 10 being composed of a laminate including at least a substrate layer 1 and adhesive layers 2 arranged on both sides of the substrate layer 1, the substrate layer 1 containing a resin with a glass transition temperature of 160°C or higher, and the adhesive layers 2 containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin.

[0061] The gasket member 10 of the present disclosure may be a pair of members bonded together and arranged to cover the outer peripheral edge of the electrode-electrolyte membrane stack from one side and the other side, as shown in FIG. 4, or a single gasket member 10 may cover the outer peripheral edge of the electrode-electrolyte membrane stack, as shown in FIG. 7.

[0062] The electrolyte membrane 21 is not particularly limited and may be, for example, one used in known solid polymer fuel cells. The electrolyte membrane 21 is formed, for example, by applying a solution containing a proton-conductive polymer electrolyte to a substrate and drying the applied solution. Examples of proton-conductive polymer electrolytes include perfluorosulfonic acid-based fluorine ion exchange resins, more specifically, perfluorocarbon sulfonic acid-based polymers (PFS-based polymers) in which the C—H bonds of hydrocarbon-based ion exchange membranes are substituted with fluorine. The introduction of highly electronegative fluorine atoms results in high chemical stability, a high degree of dissociation of sulfonic acid groups, and high ionic conductivity. Specific examples of such proton-conductive polymer electrolytes include "Nafion" (registered trademark) manufactured by DuPont, "Flemion" (registered trademark) manufactured by Asahi Glass Co., Ltd., "Aciplex" (registered trademark) manufactured by Asahi Kasei Corporation, and "GoreSelect" (registered trademark) manufactured by Gore. The concentration of the proton-conductive polymer electrolyte contained in the proton-conductive polymer electrolyte-containing solution is typically about 5 to 60 wt %, and preferably about 20 to 40 wt %. The thickness of the electrolyte membrane 21 is typically about 3 to 50 μm, and preferably about 5 to 20 μm. Although not shown, the end faces of the electrolyte membrane 21 do not need to be flush with the end faces of the catalyst layers 22 and 23. For example, the end faces of the electrolyte membrane 21 may protrude beyond the end faces of the catalyst layers 22 and 23, and the adhesive layer 2 of the gasket member 10 may cover the protruding portions of the electrolyte membrane 21.

[0063] Specifically, one of the catalyst layers 22, 23 is an anode catalyst layer and the other is a cathode catalyst layer. The catalyst layers 22, 23 are not particularly limited and may be, for example, those used in known solid polymer fuel cells. The catalyst layers 22, 23 are, for example, platinum-containing catalyst layers. The catalyst layers 22, 23 contain, for example, carbon particles carrying catalyst particles and a proton-conductive polymer electrolyte. Examples of catalyst particles include platinum and platinum compounds. Examples of platinum compounds include alloys of platinum with at least one metal selected from the group consisting of ruthenium, palladium, nickel, molybdenum, iridium, iron, etc. Typically, the catalyst particles contained in the cathode catalyst layer are platinum, and the catalyst particles contained in the anode catalyst layer are alloys of the metal and platinum. The proton-conductive polymer electrolyte may be the same material as that used in the electrolyte membrane 21.

[0064] The size and shape of the electrolyte membrane 21 and catalyst layers 22, 23 are adjusted according to the size of the polymer electrolyte fuel cell, and the size and shape of the gasket member 10 of the present disclosure are also adjusted appropriately according to these sizes so that it functions as a gasket member (i.e., has mechanical strength that can withstand heat pressing and exhibits gas barrier properties that prevent fuel and oxidant from leaking to the outside).

[0065] 4. Polymer electrolyte fuel cell The polymer electrolyte fuel cell 30 of the present disclosure is a polymer electrolyte fuel cell that utilizes the gasket member 10 of the present disclosure. That is, the polymer electrolyte fuel cell 30 of the present disclosure includes the electrode-electrolyte membrane stack 20 with the gasket member of the present disclosure.

[0066] The polymer electrolyte fuel cell 30 includes a catalyst layer-electrolyte membrane laminate, and a gas diffusion layer 24 is formed on each of the catalyst layers 22, 23 of the catalyst layer-electrolyte membrane laminate to form an electrode-electrolyte membrane laminate. The catalyst layers 22, 23 and the gas diffusion layer 24 form electrodes (anode and cathode), respectively. A gasket member 10 of the present disclosure is placed on the outer periphery of the electrolyte membrane 21 so as to surround these electrodes. Furthermore, separators 25, each having a gas flow path 26 formed therein, are placed so as to sandwich the electrode-electrolyte membrane laminate with the gasket member 10 placed thereon from above and below.

[0067] The gas diffusion layer 24 is not particularly limited and may be, for example, a layer used in a known polymer electrolyte fuel cell. That is, various gas diffusion layers constituting the anode and cathode can be used for the gas diffusion layer 24, and the gas diffusion layer 24 is made of a porous conductive substrate to efficiently supply the fuel gas and oxidant gas to the catalyst layers 22, 23. Examples of the porous conductive substrate include carbon paper and carbon cloth.

[0068] The separator 25 is not particularly limited and may be, for example, a separator used in known polymer electrolyte fuel cells. The separator 25 may be any conductive plate that is stable in the environment inside the fuel cell, and is generally a metal plate made of titanium, aluminum, copper, stainless steel, or the like, with a gas flow path 26 formed thereon. Separators 25 made of any of the above metals, with a coating of a conductive material such as carbon, silver, chromium nitride, platinum group metals or their oxides, or conductive polymers formed on the surface of the metal, may also be used.

[0069] The operating temperature of the polymer electrolyte fuel cell 30 of the present disclosure is not particularly limited, but since the gasket member 10 has excellent hydrolysis resistance in high-temperature environments, it may be used at an operating temperature of, for example, 60°C or higher, or even 100°C or higher. Increasing the operating temperature of the fuel cell increases the power density. The upper limit of the operating temperature of the polymer electrolyte fuel cell 30 of the present disclosure is, for example, 150°C or lower. [Example]

[0070] The present disclosure will be described in detail below with reference to examples and comparative examples, but the present disclosure is not limited to the examples.

[0071] <Manufacturing of gasket members for polymer electrolyte fuel cells> Example 1 A polysulfone (PSU) film (thickness 100 μm, Tg 180° C.) was prepared as the substrate layer. Next, imine-modified polypropylene was melt-extruded onto both sides of the substrate layer to form an adhesive layer with a thickness of 50 μm, thereby obtaining a gasket member for a polymer electrolyte fuel cell (thickness 200 μm) in which the adhesive layer (thickness 50 μm) / substrate layer (thickness 100 μm) / adhesive layer (thickness 50 μm) were laminated in this order.

[0072] Example 2 A polyethersulfone (PESU) film (thickness 100 μm, Tg 220° C.) was prepared as the substrate layer. Next, imine-modified polypropylene was melt-extruded onto both sides of the substrate layer to form an adhesive layer with a thickness of 50 μm, thereby obtaining a gasket member for a polymer electrolyte fuel cell (thickness 200 μm) in which the adhesive layer (thickness 50 μm) / substrate layer (thickness 100 μm) / adhesive layer (thickness 50 μm) were laminated in this order.

[0073] Example 3 A gasket member (thickness 200 μm) for a polymer electrolyte fuel cell was obtained in the same manner as in Example 1, except that a polyphenylsulfone (PPSU) film (thickness 100 μm, Tg 220°C) was used as the substrate layer instead of a polyethersulfone (PESU) film, and the adhesive layer (thickness 50 μm) was laminated in that order.

[0074] Example 4 A gasket component (thickness 200 μm) for a polymer electrolyte fuel cell was obtained in the same manner as in Example 3, except that instead of imine-modified polypropylene, imine-modified polypropylene (thickness 20 μm) and maleic anhydride-modified polypropylene (PPa, thickness 30 μm) were melt-extruded onto both sides of a polyphenylsulfone (PPSU) film (the imine-modified polypropylene was on the base layer side) as the adhesive layer, and the adhesive layer (thickness 50 μm) was laminated in that order.

[0075] Example 5 A gasket component (200 μm thick) for a polymer electrolyte fuel cell was obtained in the same manner as in Example 3, except that instead of imine-modified polypropylene, imine-modified polypropylene, polypropylene, and maleic anhydride-modified polypropylene (PPa) were melt-extruded onto both sides of a polyphenylsulfone (PPSU) film as an adhesive layer (so that the imine-modified polypropylene (20 μm thick) was on the base layer side, the maleic anhydride-modified polypropylene (20 μm thick) was on the opposite side from the base layer side, and the polypropylene (10 μm thick) was between the imine-modified polypropylene and the acid-modified polypropylene). The adhesive layer was layered in the same manner as in Example 3, with the adhesive layer (50 μm thick) / base layer (100 μm thick) / adhesive layer (50 μm thick) laminated in that order.

[0076] Example 6 A gasket component (thickness 200 μm) for a polymer electrolyte fuel cell was obtained in the same manner as in Example 3, except that instead of imine-modified polypropylene, carbodiimide-modified polypropylene (thickness 20 μm) and maleic anhydride-modified polypropylene (PPa, thickness 30 μm) were melt-extruded onto both sides of a polyphenylsulfone (PPSU) film (the carbodiimide-modified polypropylene was on the base layer side) as the adhesive layer, and the adhesive layer (thickness 50 μm) / base layer (thickness 100 μm) / adhesive layer (thickness 50 μm) were laminated in that order.

[0077] Example 7 A gasket component (200 μm thick) for a polymer electrolyte fuel cell was obtained in the same manner as in Example 3, except that instead of imine-modified polypropylene, carbodiimide-modified polypropylene, polypropylene, and maleic anhydride-modified polypropylene (PPa) were melt-extruded onto both sides of a polyphenylsulfone (PPSU) film as the adhesive layer (the carbodiimide-modified polypropylene (20 μm thick) was on the substrate layer side, the maleic anhydride-modified polypropylene (20 μm thick) was on the opposite side from the substrate layer side, and the polypropylene (10 μm thick) was between the carbodiimide-modified polypropylene and the acid-modified polypropylene). The adhesive layer was layered in the same manner as in Example 3, with the adhesive layer (50 μm thick) / substrate layer (100 μm thick) / adhesive layer (50 μm thick) laminated in that order.

[0078] (Comparative Examples 1 and 2) A gasket member for a polymer electrolyte fuel cell (thickness 200 μm) in which an adhesive layer (thickness 50 μm) / substrate layer (thickness 100 μm) / adhesive layer (thickness 50 μm) were laminated in this order was obtained in the same manner as in Example 1, except that a polyethylene naphthalate (PEN) film (thickness 100 μm, Tg 155°C), which is commonly used for the substrate layer of gasket members for polymer electrolyte fuel cells, was used instead of a polysulfone (PSU) film as the substrate layer. The gasket members for a polymer electrolyte fuel cell in Comparative Examples 1 and 2 are the same, except that the temperature conditions for the <adhesion temperature to separator> described below were evaluated at 170°C in Comparative Example 1 and 230°C in Comparative Example 2.

[0079] (Comparative Example 3) Instead of a polysulfone (PSU) film, a polyethylene naphthalate (PEN) film (thickness: 100 μm, Tg: 155°C) was used as the substrate layer, which is commonly used for substrate layers of gasket members for polymer electrolyte fuel cells. Next, a resin composition containing a compound having an isocyanate group (a two-component mixture of polyester resin and hexamethylene diisocyanate) was applied to both sides of the substrate layer to form an anchor coat layer (thickness: 0.5 g / m 2Furthermore, an adhesive layer was formed on the surface of each of the anchor coat layers on both sides by melt-extruding maleic anhydride-modified polypropylene (PPa) to a thickness of 50 μm, resulting in an adhesive layer (thickness 50 μm) / anchor coat layer (thickness 0.5 g / m 2 ) / Base layer (thickness 100 μm) / Anchor coat layer (thickness 0.5 g / m 2 A gasket member for a polymer electrolyte fuel cell (thickness: 200 μm) was obtained in which a polymer electrolyte membrane fuel cell sheet (thickness: 200 μm) and an adhesive layer (thickness: 50 μm) were laminated in this order.

[0080] <Break elongation retention rate (evaluation of hydrolysis resistance in high-temperature environments)> The gasket members for polymer electrolyte fuel cells manufactured in the examples and comparative examples were measured for their breaking elongation retention (%) after being left standing in water at 120°C for 300 hours (in a heat-resistant, pressure-resistant container) under the following measurement conditions. The results are shown in Table 1. After immersion in 120°C water and leaving the samples standing for 300 hours, the breaking elongation of the samples was measured, and the measured value was divided by the breaking elongation (initial breaking elongation) before the durability test to determine the breaking elongation retention. The breaking elongation was measured by cutting the film into strips with a width (TD) of 15 mm and a length (MD) of 50 mm, and pulling the strips using a tensile tester at a pulling rate of 200 mm / min with a gauge length of 20 mm until breaking. The test environment was 23°C, and the average value of three measurements was used. Breaking elongation retention rate (%) = Breaking elongation after durability test ÷ Breaking elongation before durability test (initial breaking elongation) × 100

[0081] <Adhesion strength to separator> The adhesive strength (N) of the solid polymer fuel cell gasket members manufactured in the examples and comparative examples to a stainless steel plate (SUS304) used as a separator was measured under the following measurement conditions. The results are shown in Table 1. Peel strength at 25°C was measured in accordance with JIS K7127:1999 as follows. A 15 mm-wide strip was cut from each sample in the TD direction, and the metal layer was bonded to the adhesive layer by hot pressing to create a measurement sample. The measurement sample was then attached to a tensile tester, and the adhesive strength (peel strength) between the metal layer and adhesive layer was measured at a tensile speed of 300 mm / min and a gauge length of 50 mm. The maximum strength at the time of peeling was recorded as the seal strength (N / 15 mm). The average value of three measurements was used. The hot pressing conditions were a fixed surface pressure of 1 MPa and a press time of 20 seconds (s), with measurements being performed at various temperatures. Specifically, the bonding temperature was increased in 10°C increments, and the adhesive strength was measured when the bonded sample was held by hand and was bonded with a strength that allowed measurement (at each of the bonding temperatures listed in Table 1). As mentioned above, the gasket members for polymer electrolyte fuel cells in Comparative Examples 1 and 2 were the same, and the adhesive strength was evaluated at a temperature condition of 170°C in Comparative Example 1 and 230°C in Comparative Example 2. In Comparative Example 1, the adhesive strength at 170°C was too small to measure.

[0082] <Separator adhesion temperature> In the measurement of adhesive strength, the temperature at which the gasket member for a polymer electrolyte fuel cell was bonded to the stainless steel plate (SUS304) was measured. The results are shown in Table 1. As mentioned above, the gasket members for a polymer electrolyte fuel cell in Comparative Examples 1 and 2 were the same, and the temperature conditions were 170°C in Comparative Example 1 and 230°C in Comparative Example 2.

[0083] [Table 1]

[0084] *1 In Comparative Example 3, an anchor coat layer was provided between the base layer and the adhesive layer.

[0085] The gasket members of Examples 1 to 7 had a base layer containing a resin with a glass transition temperature of 160°C or higher, and an adhesive layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin, and thus exhibited excellent hydrolysis resistance in high-temperature environments. Among these, Examples 3 to 7, which used PPSU for the base layer, exhibited even higher breaking elongation retention and particularly excellent hydrolysis resistance in high-temperature environments. Furthermore, in Comparative Example 1, peeling occurred at the separator (SUS304)-adhesive layer interface at an adhesion temperature of 170°C, making strength measurement impossible. In Comparative Example 2, in which the adhesion temperature was raised to 230°C, the adhesive layer underwent cohesive failure, confirming adhesion. Furthermore, Examples 4 to 7, which used gasket members in which a layer containing at least one of imine-modified polyolefin and carbodiimide-modified polyolefin and an acid-modified polyolefin were laminated on both sides of the base layer, in that order from the base layer side, not only exhibited excellent hydrolysis resistance in high-temperature environments, but also enabled a further reduction in the adhesion temperature to the separator. By lowering the temperature at which the electrode is bonded to the separator, the thermal load on the electrode-electrolyte membrane stack can be reduced and productivity can also be improved.

[0086] As described above, the present disclosure provides the following aspects of the invention. Item 1. The laminate is composed of at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 160°C or higher, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin. Item 2. The gasket member for a polymer electrolyte fuel cell according to Item 1, wherein the base layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethyltene, polyphenylene oxide, polyphenylene sulfide, and fluororesin. Item 3. The gasket member for a polymer electrolyte fuel cell according to Item 1 or 2, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin. Item 4. The gasket member for a polymer electrolyte fuel cell according to any one of Items 1 to 3, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin. Item 5. The gasket member for a polymer electrolyte fuel cell according to any one of Items 1 to 4, wherein the thickness of the substrate layer is 20 μm or more and 200 μm or less. Item 6. The gasket member for a polymer electrolyte fuel cell according to any one of Items 1 to 5, wherein the adhesive layer has a thickness of 10 μm or more and 100 μm or less. Item 7. An electrode-electrolyte membrane laminate in which a catalyst layer and a gas diffusion layer are arranged on both sides of an electrolyte membrane; a frame-shaped gasket member arranged to cover the outer peripheral edge of the electrode-electrolyte membrane stack; Equipped with the gasket member is composed of a laminate including at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 160°C or higher, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin. Item 8. The electrode-electrolyte membrane laminate with gasket member according to Item 7, wherein the base layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethyltene, polyphenylene oxide, polyphenylene sulfide, carbodiimide-modified polyolefin, and fluororesin. Item 9. The electrode-electrolyte membrane laminate with gasket member according to Item 7 or 8, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin. Item 10. The electrode-electrolyte membrane laminate with gasket member according to any one of Items 7 to 9, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin. Item 11. The electrode-electrolyte membrane laminate with gasket members according to any one of Items 7 to 10, wherein the thickness of the substrate layer is 20 μm or more and 200 μm or less. Item 12. The electrode-electrolyte membrane laminate with gasket member according to any one of Items 7 to 11, wherein the adhesive layer has a thickness of 10 μm or more and 100 μm or less. Item 13. A polymer electrolyte fuel cell comprising the electrode-electrolyte membrane laminate with gasket member according to any one of Items 7 to 12. Item 14. A method for manufacturing a gasket member for a polymer electrolyte fuel cell, which is composed of a laminate including at least a base material layer and adhesive layers disposed on both sides of the base material layer, The method includes a step of laminating the adhesive layer on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 160°C or higher, The method for producing a gasket member for a polymer electrolyte fuel cell, wherein the adhesive layer contains an imine-modified polyolefin. [Explanation of symbols]

[0087] 1 Base material layer 2 Adhesive layer 3 Anchor coat layer 10 Gasket material 11 Opening 20 Electrode-electrolyte membrane laminate with gasket member 21 Electrolyte membrane 22,23 Catalyst layer 24 Gas diffusion layer 25 Separator 26 Gas flow path 30 Polymer electrolyte fuel cell

Claims

1. The laminate is made up of at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 180°C or higher, the substrate layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyetheretherketone, polymethyltene, polyphenylene oxide, and polyphenylene sulfide; The thickness of the adhesive layer is 10 μm or more and 100 μm or less, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin.

2. 2. The gasket member for a polymer electrolyte fuel cell according to claim 1, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin.

3. 3. A gasket member for a polymer electrolyte fuel cell as described in claim 1 or 2, wherein the adhesive layer comprises, in order from the base layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin.

4. 4. The gasket member for a polymer electrolyte fuel cell according to claim 1, wherein the thickness of the substrate layer is 20 μm or more and 200 μm or less.

5. 5. The gasket member for a polymer electrolyte fuel cell according to claim 1, wherein the adhesive layer has a thickness of 15 μm or more and 100 μm or less.

6. an electrode-electrolyte membrane stack in which a catalyst layer and a gas diffusion layer are disposed on both sides of an electrolyte membrane; a frame-shaped gasket member arranged to cover the outer peripheral edge of the electrode-electrolyte membrane stack; Equipped with the gasket member is composed of a laminate including at least a base material layer and adhesive layers disposed on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 180°C or higher, the substrate layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyetheretherketone, polymethyltene, polyphenylene oxide, and polyphenylene sulfide; The thickness of the adhesive layer is 10 μm or more and 100 μm or less, The adhesive layer comprises at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin.

7. 7. The electrode-electrolyte membrane laminate with gasket member according to claim 6, wherein the adhesive layer comprises, in order from the base material layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, and a layer containing an acid-modified polyolefin.

8. 8. The electrode-electrolyte membrane laminate with gasket member according to claim 6, wherein the adhesive layer comprises, in this order from the base material layer side, a layer containing at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin, a layer containing a polyolefin, and a layer containing an acid-modified polyolefin.

9. 9. The electrode-electrolyte membrane laminate with gasket members according to claim 6, wherein the thickness of the substrate layer is 20 μm or more and 200 μm or less.

10. 10. The electrode-electrolyte membrane laminate with gasket member according to claim 6, wherein the adhesive layer has a thickness of 15 μm or more and 100 μm or less.

11. A polymer electrolyte fuel cell comprising the electrode-electrolyte membrane laminate with gasket member according to any one of claims 6 to 10.

12. A method for manufacturing a gasket member for a polymer electrolyte fuel cell, which is constituted by a laminate including at least a base material layer and adhesive layers disposed on both sides of the base material layer, comprising: The method includes a step of laminating the adhesive layer on both sides of the base material layer, the substrate layer contains a resin having a glass transition temperature of 180°C or higher, the substrate layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyetheretherketone, polymethyltene, polyphenylene oxide, and polyphenylene sulfide; The thickness of the adhesive layer is 10 μm or more and 100 μm or less, The method for producing a gasket member for a polymer electrolyte fuel cell, wherein the adhesive layer contains at least one of an imine-modified polyolefin and a carbodiimide-modified polyolefin.

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