Gasket member

Abstract

This gasket member is configured from a laminate comprising at least a substrate layer and an adhesive layer disposed on both surface sides of the substrate layer, wherein the adhesive layer contains a phenolic antioxidant that does not contain an ester group, or contains a phosphorus-based antioxidant and a phenolic antioxidant.

Description

Gasket material

[0001] The present disclosure relates to a gasket member.

[0002] BACKGROUND ART In various technical fields, gasket members are used to provide airtightness and liquidtightness to structures.

[0003] JP 2022-134703 A JP 2022-131807 A

[0004] Gasket members used in high-temperature environments (for example, in the range of 80° C. to 130° C.) are sometimes required to have hydrolysis resistance in high-temperature environments.

[0005] A primary object of the present disclosure is to provide a gasket member that has excellent hydrolysis resistance in high-temperature environments.

[0006] The inventors of the present disclosure conducted extensive research to solve the above-mentioned problems. As a result, they discovered that a gasket member composed of a laminate including a base layer and adhesive layers disposed on both sides of the base layer, wherein the adhesive layers contain a phenolic antioxidant that does not contain an ester group, or a combination of a phosphorus-based antioxidant and a phenolic antioxidant, has excellent hydrolysis resistance in high-temperature environments. The functional site of the phenolic antioxidant is the phenol moiety, and the phenolic structure is maintained even after hydrolysis. Therefore, it was thought that phenolic antioxidants would exhibit antioxidant function in high-temperature environments regardless of the presence or absence of an ester group. However, through extensive research, the inventors of the present disclosure discovered that in the adhesive layers of gasket members, phenolic antioxidants that do not contain an ester group have superior hydrolysis resistance in high-temperature environments.

[0007] The present disclosure was completed through further investigation based on such novel findings. That is, the present disclosure provides the following aspects of the invention: A gasket member comprising a laminate including a base layer and adhesive layers disposed on both sides of the base layer, wherein the adhesive layers contain a phenolic antioxidant that does not contain an ester group, or contain a phosphorus-based antioxidant and a phenolic antioxidant.

[0008] According to the present disclosure, it is possible to provide a gasket member that has excellent hydrolysis resistance in high-temperature environments.

[0009] 1 is a schematic diagram showing an example of a cross-sectional structure of a gasket member according to the present disclosure; FIG. 2 is a schematic diagram showing an example of a cross-sectional structure of a gasket member according to the present disclosure; FIG. 3 is a schematic plan view of a gasket member according to the present disclosure;

[0010] The gasket member of the present disclosure is composed of a laminate including at least a base layer and adhesive layers disposed on both sides of the base layer, the adhesive layers containing a phenolic antioxidant that does not contain an ester group, or a phosphorus-based antioxidant and a phenolic antioxidant. The gasket member of the present disclosure has excellent hydrolysis resistance in high-temperature environments.

[0011] As will be described later, the gasket member of the present disclosure can be applied to structures in a wide range of technical fields that are used in high-temperature environments.

[0012] The gasket member of the present disclosure will be described in detail below. In this specification, numerical ranges indicated with "to" mean "greater than or equal to" or "less than or equal to." For example, the notation "2 to 15 mm" means 2 mm or greater and 15 mm or less. For example, the notation "2 to 15 mm" means 2 mm or greater and 15 mm or less. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, separately described upper and lower limits, upper and lower limits, or lower and lower limits may each be combined to form a numerical range. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples.

[0013] 1. Laminated Structure and Physical Properties of Gasket Member A gasket member 10 according to the present disclosure (hereinafter sometimes referred to as gasket member 10) is composed of a laminate including at least a base material layer 1 and adhesive layers 2 disposed on both sides of the base material layer 1, as shown in Fig. 1 . That is, the gasket member 10 is composed of a laminate in which at least the adhesive layer 2, the base material 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 layer of the gasket member 10.

[0014] The gasket member 10 may include an opening 11 (see FIG. 3).

[0015] As shown in Fig. 2, the gasket member 10 may have an anchor coat layer 3 on at least one side of the surface of the base material layer 1. For example, when the base material layer 1 is formed of a film, the adhesive strength between the base material layer 1 and the adhesive layer 2 can be increased by providing the anchor coat layer 3 between the base material layer 1 and the adhesive layer 2. It is preferable to have the anchor coat layer 3 on both sides of the surface of the base material layer 1. That is, it is more preferable that the gasket member 10 is 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.

[0016] The thickness (total thickness) of the laminate constituting the gasket member 10 is adjusted depending on the size of the structure to which it is applied, and is not particularly limited, but examples include approximately 400 μm or less, approximately 300 μm or less, approximately 200 μm or less, approximately 100 μm or less, approximately 50 μm or less, or, for example, approximately 30 μm or more, approximately 100 μm or more, approximately 200 μm or more, and approximately 250 μm or more. Preferred ranges for the thickness (total thickness) of the laminate constituting the gasket member 10 include approximately 30 to 400 μm, approximately 30 to 300 μm, approximately 30 to 200 μm, approximately 30 to 100 μm, approximately 30 to 50 μm, approximately 100 to 400 μm, approximately 100 to 300 μm, approximately 100 to 200 μm, approximately 200 to 400 μm, approximately 200 to 300 μm, approximately 250 to 400 μm, and approximately 250 to 300 μm.

[0017] In the present disclosure, the total thickness of the gasket member 10 and the thickness of each layer may be appropriately selected depending on the thickness of the structure to which the gasket member is applied.

[0018] 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%.

[0019] From the viewpoint of more suitably exerting the effects of the present disclosure, the gasket member 10 of the present disclosure preferably has an adhesive strength (N / 15 mm) to a stainless steel plate (SUS304) measured by the method described below of about 25 N / 15 mm or more, and more preferably about 30 N / 15 mm or more.

[0020] <Adhesion Strength to Stainless Steel Plate (SUS304)> The adhesive strength (N) of the gasket member to a stainless steel plate (SUS304, 100 μm thick, no pretreatment such as cleaning) serving as the gasket member's adhesive target is measured under the following measurement conditions. In accordance with the provisions of JIS K7127:1999, the peel strength in a 25°C environment is measured as follows. A sample is cut out into a 15 mm wide strip in the TD (transverse direction), and the metal-adhesive layer is bonded by heat pressing to prepare a measurement sample. The heat pressing conditions were a temperature of 170°C, a surface pressure of 1 MPa, and a pressing time of 20 seconds (s). Furthermore, during the heat pressing, temperature and pressure were applied to both sides of the measurement sample. Next, the measurement sample was attached to a tensile tester, and the adhesive strength (peel strength) between the metal layer and the adhesive layer was measured at a tensile speed of 300 mm / min and a gauge length of 50 mm. The maximum strength (N / 15 mm) at the time of peeling was used. This was the average value of three measurements. The peeling direction was 180°, and the size of the adhesive joint of the stainless steel plate (SUS304) in the measurement sample was 15 mm wide and 30 mm long.

[0021] Furthermore, from the viewpoint of more suitably exerting the effects of the present disclosure, the gasket member 10 of the present disclosure has a retention rate (%) of adhesive strength (N / 15 mm) to a stainless steel plate (SUS304), measured by the method described below, of preferably not less than about 50%, more preferably not less than about 70%, and even more preferably not less than about 90%, and is, for example, not more than about 100%, with preferred ranges being about 50 to 100%, about 70 to 100%, and about 90 to 100%.

[0022] <Adhesion strength retention rate to stainless steel plate (SUS304) (evaluation of hydrolysis resistance in high-temperature environment)> After leaving the gasket member in water at 120°C (in a heat-resistant and pressure-resistant container) for 300 hours (pure water and the metal-adhesive layer sealed sample prepared by the above-mentioned method were placed in a pressure-resistant container, and the container was left to stand in a constant temperature bath at 120°C for 300 hours), the adhesion strength to stainless steel plate (SUS304) was measured by the method described above in <Adhesion strength to stainless steel plate (SUS304)>, and this is defined as the "adhesion strength after durability test to stainless steel plate (SUS304)". Next, the adhesive strength of the gasket member to the stainless steel plate (SUS304) obtained in the above <Adhesive strength to stainless steel plate (SUS304)> is defined as the "adhesive strength to stainless steel plate (SUS304) before the durability test," and the "adhesive strength to stainless steel plate (SUS304) after the durability test" is divided by the "adhesive strength to stainless steel plate (SUS304) before the durability test" to determine the "adhesive strength maintenance rate to stainless steel plate (SUS304)." Adhesive strength maintenance rate to stainless steel plate (SUS304) (%) = adhesive strength to stainless steel plate (SUS304) after the durability test / adhesive strength to stainless steel plate (SUS304) before the durability test × 100

[0023] One method for confirming the MD (Machine Direction) of a gasket member is to observe a cross section of the gasket member (e.g., a cross section of the first adhesive layer, the base material, or the 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 is observed in each cross section. 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 order of largest diameter y is calculated. The direction parallel to the cross section in which the average diameter y of the island shape is the largest is determined to be the MD.

[0024] The gasket member 10 of the present disclosure has an adhesive layer containing a phenolic antioxidant that does not contain an ester group, or a combination of a phosphorus-based antioxidant and a phenolic antioxidant, thereby improving the aforementioned "adhesion strength to stainless steel plate (SUS304)" and "adhesion strength retention rate to stainless steel plate (SUS304)." In addition, for example, the base layer 1 may be formed from a resin or metal, as described below. Among these materials, it is preferable to use a resin with a high glass transition temperature (Tg). It is also effective to use a polyolefin resin (especially an acid-modified polyolefin) as the resin forming the adhesive layer 2, or to provide an anchor coat layer 3. In other words, to further maximize the benefits of the present disclosure, it is effective to use the specific antioxidant in the adhesive layer 2, and further use a heat-resistant resin as the base layer 1, an acid-modified polyolefin as the resin for the adhesive layer 2, or to provide an anchor coat layer 3.

[0025] The environmental temperature in which the gasket member of the present disclosure is used is not particularly limited, and the gasket member exhibits excellent hydrolysis resistance even when used in a high-temperature environment. For example, the maximum temperature during use may be, for example, 50°C or higher, 80°C or higher, or 100°C or higher, and may also be, for example, 130°C or lower, 120°C or lower, or 110°C or lower. For the gasket member of the present disclosure, preferred ranges for the maximum temperature during use include, for example, approximately 50 to 130°C, approximately 50 to 120°C, approximately 50 to 110°C, approximately 80 to 130°C, approximately 80 to 120°C, approximately 80 to 110°C, approximately 100 to 130°C, approximately 100 to 120°C, and approximately 100 to 110°C. The environmental humidity in which the gasket member of the present disclosure is used is also not particularly limited, and the gasket member exhibits excellent hydrolysis resistance even when used in a high-humidity environment. The relative humidity during use of the gasket member of the present disclosure may be, for example, 80% or higher, or 90% or higher. Furthermore, the environment in which the gasket member of the present disclosure is used may be underwater.

[0026] 2. Layers forming the gasket member> [Substrate layer 1] In the present disclosure, the substrate layer 1 is a layer provided for the purpose of, for example, functioning as a substrate for the gasket member 10. The substrate layer 1 is located between two adhesive layers 2.

[0027] The base layer 1 can be made of a conventionally known material, such as polyphenylene ether, syndiotactic polystyrene, polyimide, phenolic resin, epoxy resin, acrylic resin, polyketone, cyclic olefin, polymethylpentene, polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethylpentene, polyphenylene oxide, polyphenylene sulfide, fluororesin, metal, etc. However, it is preferably made of a material having excellent hydrolysis resistance, and preferably includes polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethylpentene, polyphenylene oxide, polyphenylene sulfide, fluororesin, metal, etc. When these materials are used to form the base layer 1, the base layer 1 may contain one type of material or two or more types of materials.

[0028] 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., block copolymers of propylene and ethylene), and polypropylene random copolymers (e.g., random copolymers of propylene and ethylene); 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, a polyolefin having an alkoxysilyl group, or the like. 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.

[0029] 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 above-mentioned polyolefins, copolymers of the above-mentioned 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 anhydrides thereof, 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 anhydrides thereof, polypropylenes modified with carboxylic acids or anhydrides thereof, 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.

[0030] Polyolefins having alkoxysilyl groups are typically produced by graft copolymerizing an ethylenically unsaturated silane with a polyolefin in the presence of a radical generator, or by high-pressure radical copolymerization of ethylene with an ethylenically unsaturated silane or, optionally, other radically polymerizable monomers. Examples of the ethylenically unsaturated silane include vinyltrimethoxysilane, vinyltriethoxysilane, γ-(meth)acryloyloxypropyltrimethoxysilane, γ-(meth)acryloyloxypropyltriethoxysilane, and γ-(meth)acryloyloxypropylmethyldimethoxysilane. These can be used alone or in combination of two or more. However, the method is not limited to the above, and various other methods are also possible for production, such as reacting a maleic anhydride-modified polyolefin with γ-aminopropyltrimethoxysilane. When the substrate layer 1 contains a polyolefin having alkoxysilyl groups, the substrate layer 1 may contain only one type of polyolefin having alkoxysilyl groups, or two or more types of polyolefins having alkoxysilyl groups.

[0031] 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) containing 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 polyamides such as copolymers of these copolymers. 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.

[0032] 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.

[0033] Examples of metals include aluminum alloys, copper, zinc, titanium, and stainless steel.

[0034] 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 contains polyethersulfone, polyphenylsulfone, or polyarylate, and even more preferably contains polyphenylsulfone. The base layer 1 is preferably formed from at least one resin among these, and is particularly preferably formed from polyphenylsulfone.

[0035] Furthermore, 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 material layer 1 is preferably formed from a resin with excellent heat resistance, and the glass transition temperature (Tg) of the resin forming the base material layer 1 is preferably about 160° C. or higher, more preferably about 180° C. or higher, and even more preferably about 200° 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 shift point of a DSC curve measured by a differential scanning calorimeter (DSC).

[0036] 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 resin or metal film as 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 resin or metal nonwoven fabric as 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 nonwoven fabric substrate layer 1, thereby enhancing the physical adhesion between the substrate layer 1 and the adhesive layer 2. Therefore, when the substrate layer 1 is in the form of a nonwoven fabric, the anchor coat layer 3 described below may be provided on the surface of the substrate layer 1, but the adhesion between the substrate layer 1 and the adhesive layer 2 can be sufficiently enhanced without providing the anchor coat layer 3. On the other hand, when the substrate layer 1 is in the form of a film, it is preferable to provide the anchor coat layer 3 on the surface of the substrate layer 1 from the viewpoint of enhancing the adhesion between the substrate layer 1 and the adhesive layer 2.

[0037] The base material layer 1 may be a single layer or may be composed of two or more layers. When the base material layer 1 is composed of two or more layers, the materials and thicknesses of the layers may be the same or different.

[0038] 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 the 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.

[0039] In the present disclosure, the thickness of the base layer 1 is adjusted as appropriate depending on the size of the structure to which the gasket member is applied, but 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, from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, 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 base 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.

[0040] When the base material layer 1 is in the form of a nonwoven fabric, the basis weight of the base material layer 1 is adjusted appropriately depending on the size of the structure to which the gasket member is applied, 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 More preferably, about 30 g / m or less 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 2 degree, 15-50g / m 2 degree, 15-40g / m 2 degree, 15-30g / m 2 The degree of

[0041] [Adhesive Layer 2] In the gasket member 10, adhesive layers 2 are disposed on both sides of the base material layer 1. The adhesive layers 2 on both sides of the gasket member 10 constitute the outermost layers of the gasket member 10. The adhesive layer 2 disposed on one side and the adhesive layer 2 disposed on the other side may be made of the same material, may have a different thickness, or may be made of different materials.

[0042] The adhesive layer 2 contains an antioxidant. The antioxidant is a phenolic antioxidant not containing an ester group, or a combination of a phosphorus-based antioxidant and a phenolic antioxidant. For example, the antioxidant contained in the adhesive layer 2 may be only an ester-based phenolic antioxidant, a combination of a phosphorus-based antioxidant and a phenolic antioxidant, or a combination of three types: a phosphorus-based antioxidant, an ester-based phenolic antioxidant, and an ester-containing phenolic antioxidant. The adhesive layer 2 may contain only one type of phosphorus-based antioxidant, one type of ester-based phenolic antioxidant, and one type of ester-containing phenolic antioxidant, or two or more types of phosphorus-based antioxidant, one type of ester-based phenolic antioxidant, and one type of ester-containing phenolic antioxidant. Furthermore, the adhesive layer 2 may contain other antioxidants in addition to the phosphorus-based antioxidant and the phenolic antioxidant (the ester-based phenolic antioxidant not containing an ester group, the ester-containing phenolic antioxidant).

[0043] As long as the effects of the present disclosure are achieved, the phosphorus-based antioxidant is not particularly limited, but preferred phosphorus-based antioxidants include compounds represented by the following general formulas (Aa) and (Ab).

[0044]

[0045] The presence of the compounds represented by general formulas (Aa) and (Ab) in the adhesive layer 2 can be confirmed by various analytical methods such as NMR.

[0046] In general formula (Aa), R 11a and R 12a are each independently an alkyl group having 1 to 18 carbon atoms or a phenyl group which may have a substituent. 11a and R12a is preferably a phenyl group which may have a substituent. The compound represented by general formula (Aa) contained in the adhesive layer 2 may be one type or two or more types.

[0047] In general formula (Aa), R 11a and R 12a It is preferable that the phenyl groups in R each independently have, as a substituent, at least one group selected from the group consisting of an alkyl group having 1 to 9 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms. Among these groups, it is preferable that the phenyl group has, as a substituent, at least one of an alkyl group having 1 to 9 carbon atoms and an aralkyl group having 7 to 12 carbon atoms. Furthermore, 11a and R 12a The number of substituents on the phenyl group may be 1 to 5, preferably 2 or 3.

[0048] In general formula (Ab), each Ar group is independently an aromatic group which may have a substituent, and preferably an optionally substituted phenyl group. Examples of the substituent include an alkyl group having 1 to 9 carbon atoms, and preferably an alkyl group having 3 to 5 carbon atoms. The number of substituents in the group Ar is preferably 1 to 3, and more preferably 2, independently.

[0049] Preferable specific examples of the compound represented by the general formula (Aa) include a compound represented by the following formula (Aa') and a compound represented by the following formula (Aa'').

[0050]

[0051] In the general formula (Aa'), R n1 and R n2 Each of p's independently represents an integer of 0 to 3, and each of q's independently represents an integer of 0 to 5. In addition, in general formula (Aa″), R n3each independently represents an alkyl group having 1 to 9 carbon atoms, and each s independently represents an integer of 0 to 3.

[0052] In addition, in the general formula (Aa′), the substituent R n1 are each independently an alkyl group having 1 to 18 carbon atoms or a phenyl group which may have a substituent. n2 are preferably each independently an alkyl group having 1 to 18 carbon atoms or a phenyl group which may have a substituent.

[0053] Furthermore, preferred specific examples of the compound represented by general formula (Aa) include a compound represented by formula (Aa1) below (bis(2,4-dicumylphenyl)pentaerythritol diphosphite) and a compound represented by formula (Aa2) below (bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite).

[0054]

[0055] It is particularly preferable that the adhesive layer 2 contains a compound represented by the formula (Aa1) as the compound represented by the general formula (Aa).

[0056] A preferred specific example of the compound represented by the general formula (Ab) is a compound represented by the following formula (Ab').

[0057]

[0058] Furthermore, a specific preferred example of the compound represented by the general formula (Ab) is a compound represented by the following formula (Ab1) (tris(2,4-di-t-butylphenoxy)phosphine).

[0059]

[0060] When the adhesive layer 2 contains a phosphorus-based antioxidant, the content of the phosphorus-based antioxidant is not particularly limited as long as the effects of the present disclosure are achieved. However, from the viewpoint of more optimally achieving the effects of the present disclosure, the content is preferably about 0.01% by mass or more, more preferably about 0.03% by mass or more, and even more preferably about 0.05% by mass or more. Furthermore, the content is preferably about 2% by mass or less, more preferably about 1% by mass or less, and even more preferably about 0.5% by mass or less. Preferred ranges for the content include about 0.01 to 2% by mass, about 0.01 to 1% by mass, about 0.01 to 0.5% by mass, about 0.03 to 2% by mass, about 0.03 to 1% by mass, about 0.03 to 0.5% by mass, about 0.05 to 2% by mass, about 0.05 to 1% by mass, and about 0.05 to 0.5% by mass. When the adhesive layer 2 contains multiple types of phosphorus-based antioxidants, it is preferable that the content of each phosphorus-based antioxidant satisfy these values.

[0061] The phenolic antioxidant is either a phenolic antioxidant that does not contain an ester group or a phenolic antioxidant that contains an ester group. In the adhesive layer 2, the phenolic antioxidant that does not contain an ester group does not need to be used in combination with a phosphorus-based antioxidant (although, as described below, using these in combination is preferred). On the other hand, in the adhesive layer 2, the phenolic antioxidant that contains an ester group is used in combination with a phosphorus-based antioxidant.

[0062] The phenolic antioxidant containing an ester group is preferably a compound represented by the following general formula (Ba) or (Bb):

[0063]

[0064] In general formula (Ba), R 8 is a hydrocarbon group, -(CH2CH2O) s The hydrocarbon group may be a chain or a cyclic group, and is preferably an aliphatic hydrocarbon group having 1 to 20 carbon atoms. s is 1, 2, 3, or 4. R 9is an aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 1 to 6 carbon atoms. 10 From R 14 At least one of the hydroxyl groups is a hydroxyl group. Only one hydroxyl group is present in the para position (i.e., R 12 is a hydroxyl group). 10 From R 14 Among these, at least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 4 to 10 carbon atoms. 10 From R 14 Among R, at least one substituent adjacent to the hydroxyl group is preferably a t-butyl group. 10 From R 14 In general formula (D), the substituents other than hydroxyl groups and aliphatic hydrocarbon groups having 4 or more carbon atoms are hydrogen atoms, methyl groups, ethyl groups, or propyl groups. q is 1, 2, 3, or 4. 26 , R 27 is a hydrocarbon group. The hydrocarbon group may be linear or cyclic, and is preferably an alkylene group having 1 to 8 carbon atoms.

[0065] In addition, in general formula (Bb), R 15 is a hydrocarbon group. The hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms. 16 From R 20 At least one of the hydroxyl groups is a hydroxyl group. Only one hydroxyl group is present in the para position (i.e., R 18 is a hydroxyl group). 16 From R 20 Among these, at least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 4 to 10 carbon atoms. 16 From R 20Among R, at least one substituent adjacent to the hydroxyl group is preferably a t-butyl group. 16 From R 20 Among R, the substituents other than a hydroxyl group and an aliphatic hydrocarbon group having 4 or more carbon atoms are a hydrogen atom, a methyl group, an ethyl group, or a propyl group. 21 From R 25 At least one of the hydroxyl groups is a hydroxyl group. Only one hydroxyl group is present in the para position (i.e., R 23 is a hydroxyl group). 21 From R 25 Among these, at least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 4 to 10 carbon atoms. 21 From R 25 Among R, at least one substituent adjacent to the hydroxyl group is preferably a t-butyl group. 21 From R 25 In the above, the substituents other than hydroxyl groups and aliphatic hydrocarbon groups having 4 or more carbon atoms are hydrogen atoms, methyl groups, ethyl groups, or propyl groups. r is 1, 2, 3, or 4.

[0066] Furthermore, preferred specific examples of the compounds represented by the general formulas (Ba) and (Bb) include a compound represented by the following formula (B1) (tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane), a compound represented by the following formula (B2) (octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), and a compound represented by the following formula (B3) (triethylene glycol bis(3-t Examples of the compound represented by the formula (B1) include a compound represented by the formula (B2) (3,9-bis[2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro(5,5)undecane), and a compound represented by the formula (B3) (ethylene bis[3,3-bis(3-t-butyl-4-hydroxyphenyl)butyrate). In the formula, t-Bu is a t-butyl group.

[0067]

[0068] When the adhesive layer 2 contains a phenolic antioxidant containing an ester group, the content of the phenolic antioxidant containing an ester group is not particularly limited as long as the effects of the present disclosure are achieved. However, from the viewpoint of more optimally achieving the effects of the present disclosure, the content is preferably about 0.01% by mass or more, more preferably about 0.03% by mass or more, and even more preferably about 0.05% by mass or more. Furthermore, the content is preferably about 2% by mass or less, more preferably about 1% by mass or less, and even more preferably about 0.5% by mass or less. Preferred ranges for the content include about 0.01 to 2% by mass, about 0.01 to 1% by mass, about 0.01 to 0.5% by mass, about 0.03 to 2% by mass, about 0.03 to 1% by mass, about 0.03 to 0.5% by mass, about 0.05 to 2% by mass, about 0.05 to 1% by mass, and about 0.05 to 0.5% by mass. When the adhesive layer 2 contains a phenolic antioxidant containing multiple types of ester groups, it is preferable that the content of each phenolic antioxidant containing an ester group satisfies these values.

[0069] The phenolic antioxidant containing no ester group is preferably a compound represented by the following general formula (C):

[0070]

[0071] In general formula (C), R 1 represents an aliphatic hydrocarbon group, an aromatic group, or an isocyanurate group, a group: —CO—NR a -NR b -CO-, and R a and R b are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 1 to 12 carbon atoms. The aromatic group is preferably an aromatic group having 6 to 20 carbon atoms. R 2 is a methylene group or a carbonyl group. 3 From R 7 At least one of the substituents is a hydroxyl group.3 From R 7 Among these, at least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms. The aliphatic hydrocarbon group may be linear or cyclic, and is preferably an aliphatic hydrocarbon group having 4 to 10 carbon atoms. 3 From R 7 Among R, at least one substituent adjacent to the hydroxyl group is preferably a t-butyl group. 3 From R 7 In the above, the substituents other than hydroxyl groups and aliphatic hydrocarbon groups having 4 or more carbon atoms are hydrogen atoms, methyl groups, ethyl groups, or propyl groups, and n is 2 or 3. m is 0 or 1. p is 0 or 1.

[0072] Furthermore, preferred specific examples of the compound represented by the general formula (C) include 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl- 4-hydroxybenzyl)benzene, 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol], 2,2'-methylenebis(6-cyclohexyl-p-cresol), 2,2'-methylenebis(6-t-butyl-4-ethylphenol, 2,2'-methylenebis(6-t-butyl-p-cresol), 2,2,6,6-tetra-t-butyl-4,4-dihydroxyphenyl, and N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine.

[0073]

[0074] Among these, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine are more preferred. N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine, which is a phenolic antioxidant not containing an ester group, functions as a metal deactivator (a compound having metal deactivating ability). Therefore, when N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine is used as an antioxidant, there is an advantage that it is not necessary to further add another metal deactivator.

[0075] When the adhesive layer 2 contains a phenolic antioxidant that does not contain an ester group, the content of the phenolic antioxidant that does not contain an ester group is not particularly limited as long as the effects of the present disclosure are achieved. However, from the viewpoint of more optimally achieving the effects of the present disclosure, the content is preferably about 0.01% by mass or more, more preferably about 0.03% by mass or more, and even more preferably about 0.05% by mass or more. Furthermore, the content is preferably about 2% by mass or less, more preferably about 1% by mass or less, and even more preferably about 0.5% by mass or less. Preferred ranges for the content include about 0.01 to 2% by mass, about 0.01 to 1% by mass, about 0.01 to 0.5% by mass, about 0.03 to 2% by mass, about 0.03 to 1% by mass, about 0.03 to 0.5% by mass, about 0.05 to 2% by mass, about 0.05 to 1% by mass, and about 0.05 to 0.5% by mass. When the adhesive layer 2 contains multiple types of ester group-free phenolic antioxidants, it is preferable that the content of each ester group-free phenolic antioxidant satisfies these values.

[0076] From the viewpoint of more suitably exerting the effects of the present disclosure, the adhesive layer 2 preferably contains a phenolic antioxidant that does not contain an ester group, more preferably contains a phosphorus-based antioxidant and a phenolic antioxidant that does not contain an ester group, and even more preferably contains a phosphorus-based antioxidant, a phenolic antioxidant that does not contain an ester group, and a phenolic antioxidant that contains an ester group. An adhesive layer that contains a phosphorus-based antioxidant and a phenolic antioxidant that contains an ester group effectively suppresses resin deterioration during high-temperature melting in melt extrusion, so that by containing a phosphorus-based antioxidant, a phenolic antioxidant that contains an ester group, and a phenolic antioxidant that does not contain an ester group, it is possible to increase both the adhesive strength before a durability test and the adhesive strength retention rate after a durability test.

[0077] The antioxidant content can be identified by the following method. The adhesive layer is immersed in a solvent to elute the antioxidant, and the solution containing the antioxidant obtained by elution is analyzed using a liquid chromatograph (LC), liquid chromatography mass spectrometry (LC / MS), or gas chromatography mass spectrometer (GC-MS) to identify the type of antioxidant in the adhesive layer. Solutions containing antioxidants at several concentrations are prepared, and the antioxidant concentrations in the solutions containing the antioxidants are quantified using a created calibration curve, and the amount of antioxidant in the adhesive layer is calculated.

[0078] As described above, the adhesive layer 2 may be a single layer or multiple layers. When the adhesive layer 2 is multiple layers, at least one layer contained in the adhesive layer 2 contains a phenolic antioxidant that does not contain an ester group, or contains a phosphorus-based antioxidant and a phenolic antioxidant. For example, these antioxidants may be contained in both the thermally adhesive resin layer 41 and the adhesive layer 42, or may be contained only in the thermally adhesive resin layer 41, or may be contained only in the adhesive layer 42. By containing these antioxidants in at least one of the layers constituting the adhesive layer 2, deterioration of the layer due to high temperatures is suppressed, allowing the layer to exhibit high adhesiveness. Furthermore, because deterioration is suppressed even when the resin forming the adhesive layer is heated to a higher temperature than conventional (e.g., 300°C or higher) to form the adhesive layer, lead time can be shortened.

[0079] The adhesive layer 2 may further contain a bifunctional processing stabilizer. Specific examples of bifunctional processing stabilizers include 1'-hydroxy[2,2'-ethylidenebis[4,6-bis(1,1-dimethylpropyl)benzene]]-1-yl acrylate and 2-t-butyl-4-methyl-6-(2-hydroxy-3-t-butyl-5-methylbenzyl)phenyl acrylate. When a bifunctional processing stabilizer is contained in the adhesive layer 2, the bifunctional processing stabilizer may be one type or two or more types.

[0080] When a bifunctional processing stabilizer is contained in the adhesive layer 2, the content of the bifunctional processing stabilizer in the adhesive layer 2 is not particularly limited as long as the effects of the present disclosure described above are achieved. However, from the viewpoint of more optimally achieving the effects of the present disclosure, the content is preferably about 0.01% by mass or more, more preferably about 0.03% by mass or more. Furthermore, the content is preferably about 0.5% by mass or less, more preferably about 0.3% by mass or less, and even more preferably about 0.2% by mass or less. Preferred ranges for the content include about 0.01 to 0.5% by mass, about 0.01 to 0.3% by mass, about 0.01 to 0.2% by mass, about 0.03 to 0.5% by mass, about 0.03 to 0.3% by mass, and about 0.03 to 0.2% by mass. When multiple types of bifunctional processing stabilizers are contained in the adhesive layer 2, it is preferable that the content of each bifunctional processing stabilizer satisfy these values.

[0081] In addition, additives such as elastomers, fillers, flame retardants, antiblocking agents, light stabilizers, tackifiers, antistatic agents, metal deactivators, and ion scavengers 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. Only one type of additive may be used, or two or more types may be mixed and used.

[0082] Metal deactivators react with metal ions present in the resin composition to form a chelate compound, thereby inactivating or reducing the ability of the metal ions to initiate resin degradation or act as a catalyst. Examples of metal deactivators include hydrazine compounds such as N,N'-bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hydrazine, distearylhydrazine, dilauroylhydrazine, dicaproylhydrazine, dioctanoylhydrazine, N,N'-bis(2-ethylhexanoyl)hydrazine, salcitoyl-benzoylhydrazine, and salicylidenesalicyloylhydrazine; isophthalic acid bis(α-phenoxypropionyl)hydrazide; hydrazide compounds such as oxalo-bis-12-hydroxybenzylidenehydrazide, bis-salicyloyl(β,β'-thiodipropionic acid)hydrazide, bis-acetadipic acid hydrazide, and decamethylenedicarboxylic acid disalicyloylhydrazide; and nitrogen-containing aromatic compounds such as 3-(N-salicyloyl)amino-1,2,4-triazole, benzotriazole, 3-amino-1,2,4-triazole, 1,3-diphenyltriazine, and 5-phenyltetrazole. Other examples include N-salicyloyl-N'-aldehyde hydrazine, N,N-dibenzal(oxalhydrazide), N,N-bis(3,5-di-t-butyl-hydroxyhydrocinnamate), and 2,2'-oxamido-bis-ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate. The metal deactivators may be used alone or in combination of two or more.

[0083] Preferred metal deactivators of the present disclosure are 3-(N-salicyloyl)-amino-1,2,4-triazole, decamethylenedicarboxylic acid disalicyloylhydrazide, and N,N'-bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hydrazine. The content of the metal deactivator in the adhesive layer is 10 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the adhesive layer. Setting the amount of metal deactivator to 10 parts by weight or less is preferred in that bleeding out from the adhesive layer surface can be suppressed.

[0084] The ion trapping agent suppresses the deterioration of the adhesive layer by trapping ions that accelerate the deterioration of the adhesive layer. The ion trapping agent used in the present invention includes a cation trapping agent capable of trapping cations, an anion trapping agent capable of trapping anions, and a dual ion trapping agent capable of trapping both cations and anions, and any of the conventionally known ion trapping agents can be used.

[0085] Organic ion exchangers used as ion trapping agents include compounds having a polymeric acid to which acidic groups such as acidic hydroxyl groups, carboxyl groups, and sulfonic groups are bonded, while inorganic ion exchangers used as ion trapping agents include hydrous oxides of metals, etc. Specific examples of inorganic ion exchangers include hydrous oxides of Si, Ti, Nb, Sn, Zr, Mg, Al, Sb, Fe, etc., phosphates of tetravalent metals such as Zr, Sn, and Ti, and synthetic zeolites.

[0086] (Cation Scavenger) Cation scavengers have a high function of capturing cations such as metal ions. Examples of inorganic cation scavengers include manganese compounds (hydrous manganese dioxide, etc.), antimony compounds (crystalline antimonic acid, hydrous antimony pentoxide, etc.), zirconium compounds (zirconium phosphate, zirconium molybdate, zirconium tungstate, etc.), silicate compounds (aluminosilicates, synthetic aluminosilicates, etc.), phosphate compounds (titanium phosphate, tin phosphate, etc.), cerium(III) oxalate, ammonium molybdophosphate, potassium hexacyanoferrate(III)cobalt(II), natural green sand, stabilized green sand, and Mn2+-type green sand. Among these, antimony compounds and zirconium compounds have a high ability to capture cations.

[0087] (Anion Scavenger) Anion scavengers have a high function of capturing anions such as halogen ions. Examples of anion scavengers include bismuth compounds (such as hydrated bismuth oxide and hydrated bismuth nitrate), magnesium-aluminum composite oxides (such as magnesium aluminum hydrotalcite), phosphate compounds (such as lead hydroxide phosphate), and zirconium compounds (such as zirconium hydroxide). Examples of bismuth oxide compounds include those represented by the general formula BiOX (OH) Y (No. 3) Z [wherein X is a positive number between 0.9 and 1.1, Y is a positive number between 0.6 and 0.8, and Z is a positive number between 0.2 and 0.4]. Magnesium-aluminum composite oxides are, for example, represented by the general formula Mg x Al y (OH) 2x+3y-2z (CO3) z mH2O (x, y, and z have the relationships 0<y / x≦1, 0≦z / y<1.5, and m is a positive number).

[0088] (Ambidextrous ion trapping agent) Ambidextrous ion trapping agents are inorganic compounds with ambidextrous ion exchange properties that simultaneously have cation adsorption sites and anion adsorption sites, and typical examples include antimony-bismuth compounds, zirconium-bismuth compounds, aluminum-magnesium-zirconium compounds, etc. Furthermore, the ambidextrous ion trapping agent can also be a mixture of a cation trapping agent appropriately selected from the zirconium compounds, antimony compounds, phosphate compounds, etc., as already explained, and an anion trapping agent appropriately selected from the bismuth compounds, magnesium-aluminum compounds, etc.

[0089] The adhesive layer 2 is preferably formed from a resin that has excellent adhesion to the object to be adhered (e.g., resin, metal, etc.) (i.e., a resin that contains a phenolic antioxidant that does not contain the above-mentioned ester group and has excellent adhesion, or a resin that contains a phosphorus-based antioxidant and a phenolic antioxidant and has excellent adhesion). Examples of resins that can be used to form the adhesive layer 2 include polyolefin resins, pressure-sensitive adhesives (acrylic resins, aliphatic polyamides, etc.), and thermosetting resins (epoxy resins, phenolic resins, etc.). The adhesive layer 2 may contain only one type of resin, or two or more types of resins.

[0090] Examples of polyolefin-based resins include the same resins as those exemplified for the base layer 1. Among these, the adhesive layer 2 preferably contains at least one of acid-modified polyolefins, imine-modified polyolefins, carbodiimide-modified polyolefins, and alkoxysilyl group-containing polyolefins because of their excellent adhesion to metals, and is more preferably formed from acid-modified polyolefins and / or alkoxysilyl group-containing polyolefins. Furthermore, among acid-modified polyolefins, acid-modified polypropylene is preferred. In the present disclosure, the use of acid-modified polyolefins, together with the base layer 1, can suitably enhance the hydrolysis resistance of the gasket member 10 in high-temperature environments.

[0091] Examples of polyolefins having alkoxysilyl groups include polypropylenes having alkoxysilyl groups, polyethylenes having alkoxysilyl groups, and ethylene-vinyl acetate copolymers having alkoxysilyl groups. In view of their excellent solvent resistance and acid resistance, polypropylenes having alkoxysilyl groups and polyethylenes having alkoxysilyl groups are preferred.

[0092] The adhesive layer 2 may be a single layer or may be composed of two or more layers. When the adhesive layer 2 is composed of two or more layers, the materials and thicknesses of the layers may be the same or different. Even when the adhesive layer 2 is composed of two or more layers, the outermost layer of the gasket member 10 preferably contains an acid-modified polyolefin, and more preferably is formed from an acid-modified polyolefin, because this layer has excellent adhesion to metal.

[0093] The thickness of the adhesive layer 2 is adjusted appropriately depending on the size of the structure to which the gasket member is applied, but is preferably about 10 μm or more, more preferably about 15 μm or more, and even more preferably about 20 μm or more, from the viewpoint of suitably enhancing the hydrolysis resistance of the gasket member 10 in a high-temperature environment, 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.

[0094] The laminate of the base material layer 1 and the adhesive layers 2 on both sides thereof can be produced, for example, by extruding a resin that forms the adhesive layer 2 onto both sides of a pre-prepared base material layer 1, or by simultaneously extruding the resin that forms the base material layer 1 and the resin that forms the adhesive layer 2. Alternatively, the laminate can be produced by extruding the base material layer 1 between pre-prepared adhesive layers 2. The method for extruding and laminating the resin is not particularly limited, and known methods such as extrusion lamination, T-die lamination, inflation extrusion, and thermal lamination can be applied. When providing the anchor coat layer 3 described below, a resin that forms the anchor coat layer 3 or the like can be applied to at least one side of the surface of the base material layer 1, and then an adhesive layer can be laminated on top of that.

[0095] [Anchor Coat Layer 3] The anchor coat layer 3 is a layer that is provided on at least one surface of the base layer 1 as needed for the purpose of increasing the adhesion between the base layer 1 and the adhesive layer 2. The anchor coat layer 3 is preferably provided on both surfaces of the base layer 1.

[0096] As described above, the base layer 1 is preferably formed from a resin having excellent heat resistance, but resins having excellent heat resistance generally have the property of having low adhesiveness to other resins. Therefore, when a highly heat-resistant resin film having a glass transition temperature (Tg) of about 160° C. or higher is used for the base layer 1, it is effective to provide the anchor coat layer 3 from the viewpoint of increasing the adhesiveness between the base layer 1 and the adhesive layer 2.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] The thickness of the anchor coat layer 3 is adjusted as appropriate depending on the size of the structure to which the gasket member is applied, 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 More preferably, about 3 g / m or less 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

[0101] The gasket member of the present disclosure is not particularly limited in its application, and because it has excellent hydrolysis resistance in high-temperature environments, it can be suitably used in structures used in high-temperature environments. For example, energy conversion devices are sometimes used in high-temperature environments, making the gasket member of the present disclosure suitable for application. Specific examples of energy conversion devices include solar power generation devices and thermoelectric conversion devices. For example, in the case of solar power generation devices, the gasket member of the present disclosure can be suitably used in sealing materials and backing materials (back sheets). The gasket member of the present disclosure may have a shape that allows it to be used as a gasket as is. Furthermore, the gasket member of the present disclosure can also be used as a gasket after the laminate (laminate sheet) constituting the gasket member is molded into a shape corresponding to the shape of the application object.

[0102] 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.

[0103] <Production of Gasket Member> (Examples 1-18, 21-28 and Comparative Examples 1-4) A polyphenylsulfone (PPSU) film (thickness 100 μm, Tg 220° C.) was prepared as a substrate layer. Next, polymethylene polyphenyl polyisocyanate (one-component curing type) was applied to both sides of the substrate layer to form an anchor coat layer (thickness 0.5 g / m 2 Furthermore, maleic anhydride-modified polypropylene (PPa) containing an antioxidant, an ion scavenger, and a metal deactivator (the contents in the adhesive layer are shown in Tables 1 and 2) described below was melt-extruded to a thickness of 50 μm on the surface of each of the anchor coat layers on both sides, to form an adhesive layer, resulting in a composition of adhesive layer (thickness 50 μm) / anchor coat layer (thickness 0.5 g / m 2 , 0.4 μm) / substrate layer (thickness 100 μm) / anchor coat layer (thickness 0.5 g / m 2 A gasket member (thickness: 200.8 μm) was obtained in which a 100.8 μm thick film / adhesive layer (thickness: 50 μm) were laminated in this order.

[0104] Example 19 A gasket member was obtained in the same manner as in Example 9, except that the maleic anhydride-modified polypropylene of Example 9 was replaced with a mixture of maleic anhydride-modified polypropylene / alkoxysilyl group-containing polypropylene = 9 / 1 (mass ratio).

[0105] Example 20 A gasket member was obtained in the same manner as in Example 9, except that the maleic anhydride-modified polypropylene of Example 9 was replaced with a mixture of maleic anhydride-modified polypropylene / polyethylene having an alkoxysilyl group=9 / 1 (mass ratio).

[0106] <Antioxidants> (Phosphorus-based antioxidants) Aa1: bis(2,4-dicumylphenyl)pentaerythritol diphosphite Ab1: tris(2,4-di-t-butylphenoxy)phosphine

[0107] (Phenol-based antioxidant containing an ester group) B1: Tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane

[0108] (Phenol-based antioxidants not containing an ester group) C1: 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione C2: 1,3,5-tris[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione C3: 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene C4: N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine

[0109] (Metal deactivator) D1: 3-(N-salicyloyl)-1H-amino-1,2,4-triazole

[0110] (Ion scavenger) E1: Zr-Mg-Al based double ion exchanger

[0111] <Adhesion Strength to Stainless Steel Plate (SUS304)> For each of the gasket members manufactured in the Examples and Comparative Examples, the adhesive strength (N) to a stainless steel plate (SUS304, 100 μm thick, no pretreatment such as cleaning) serving as the gasket member's adhesive target was measured under the following measurement conditions. The results are shown in Table 1. In accordance with JIS K7127:1999, peel strength in a 25°C environment was measured as follows. A sample was cut into a 15 mm wide strip in the TD direction from the sample, and the metal-adhesive layer was bonded by hot pressing to prepare a measurement sample. Next, the measurement sample was attached to a tensile tester, and the adhesive strength (peel strength) between the metal layer and the adhesive layer was measured at a tensile speed of 300 mm / min and a gauge length of 50 mm. The maximum strength (N / 15 mm) at the time of peeling was used. This was the average of three measurements. The adhesive strength measurement was also performed on the adhesive layer on one side of the sample. The heat press conditions were fixed at a temperature of 170°C, a surface pressure of 1 MPa, and a press time of 20 seconds (s). The heat press applied temperature and pressure to both sides of the sample. The peel direction was 180°, and the bonded area of ​​the stainless steel plate (SUS304) in the sample was 15 mm wide and 30 mm long.

[0112] <Adhesion strength retention rate to stainless steel plate (SUS304) (evaluation of hydrolysis resistance in high-temperature environment)> (Examples 1 to 20 and Comparative Examples 1 and 2) For the gasket members produced in Examples 1 to 20 and Comparative Examples 1 and 2, after being left to stand in water at 120°C (in a heat-resistant and pressure-resistant container) for 300 hours (pure water and the metal-adhesive layer sealed sample produced by the above-mentioned method were placed in a pressure-resistant container, and left to stand in a constant temperature bath at 120°C for 300 hours), the adhesion strength to stainless steel plate (SUS304) was measured using the method described above in <Adhesion strength to stainless steel plate (SUS304)>, and this was taken as the adhesion strength after the durability test to stainless steel plate (SUS304). Next, the adhesive strength of the gasket member obtained in the above <Adhesive strength to stainless steel plate (SUS304)> to the stainless steel plate (SUS304)> was defined as the "adhesive strength to stainless steel plate (SUS304) before the durability test," and the "adhesive strength to stainless steel plate (SUS304) after the durability test" was divided by the "adhesive strength to stainless steel plate (SUS304) before the durability test" to determine the "adhesive strength retention rate to stainless steel plate (SUS304)." Furthermore, the adhesive strength retention rate (%) to the stainless steel plate (SUS304) was evaluated according to the following criteria. Note that ratings A, B, and C were considered to be acceptable, and rating D was considered to be unacceptable. The results are shown in Table 1.

[0113] Adhesion strength retention rate (%) to stainless steel plate (SUS304) = Adhesion strength after durability test to stainless steel plate (SUS304) ÷ Adhesion strength before durability test to stainless steel plate (SUS304) × 100 A: Adhesion strength retention rate to stainless steel plate (SUS304) is 90% or more. B: Adhesion strength retention rate to stainless steel plate (SUS304) is 70% or more and less than 90%. C: Adhesion strength retention rate to stainless steel plate (SUS304) is 50% or more and less than 70%. D: Adhesion strength retention rate to stainless steel plate (SUS304) is less than 50%.

[0114] (Examples 21-28 and Comparative Examples 3-4) For the gasket members produced in Examples 21-28 and Comparative Examples 3-4, after leaving them in water (in a heat-resistant and pressure-resistant container) at 120°C for 600 hours (pure water and the metal-adhesive layer sealed sample produced by the above method were placed in a pressure-resistant container and left to stand in a thermostatic chamber at 120°C for 600 hours), the adhesive strength to a stainless steel plate (SUS304) was measured in the same manner as in Examples 1-20 and Comparative Examples 1-2. The adhesive strength retention rate (%) to a stainless steel plate (SUS304) was evaluated according to the following criteria. Evaluations A1, A2, B, and C were considered acceptable, and evaluation D was considered unacceptable. The results are shown in Table 2. A1: Adhesive strength retention rate to a stainless steel plate (SUS304) is 95% or more. A2: Adhesive strength retention rate to a stainless steel plate (SUS304) is 90% or more but less than 95%. B: The adhesive strength retention rate to stainless steel plate (SUS304) is 70% or more and less than 90%. C: The adhesive strength retention rate to stainless steel plate (SUS304) is 50% or more and less than 70%. D: The adhesive strength retention rate to stainless steel plate (SUS304) is less than 50%.

[0115]

[0116] In Table 1, the values ​​in parentheses indicate the content (mass %) of each antioxidant and ion scavenger in the adhesive layer.

[0117] The gasket members of Examples 1 to 20 were composed of a laminate including a base layer and adhesive layers disposed on both sides of the base layer, and the adhesive layers contained a phenolic antioxidant that did not contain an ester group, or contained a phosphorus-based antioxidant and a phenolic antioxidant. The gasket members of Examples 1 to 20 had a high adhesive strength retention rate to a stainless steel plate (SUS304) that was used as an object to be bonded to the gasket members, and were excellent in hydrolysis resistance in high-temperature environments.

[0118]

[0119] In Table 2, C4 is a component that can also function as a metal deactivator.

[0120] In Table 2, the values ​​in parentheses indicate the content (mass %) of each antioxidant and metal deactivator in the adhesive layer.

[0121] The gasket members of Examples 21 to 28 were composed of a laminate including a base layer and adhesive layers disposed on both sides of the base layer, and the adhesive layers contained a phenolic antioxidant that did not contain an ester group, or a combination of a phosphorus-based antioxidant and a phenolic antioxidant. The gasket members of Examples 20 to 27 exhibited high adhesive strength retention to a stainless steel plate (SUS304) that served as the gasket member's bonded object, and excellent hydrolysis resistance in high-temperature environments. In particular, Examples 21, 22, 26, and 27, which used N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine as the phenolic antioxidant that did not contain an ester group, exhibited high adhesive strength retention to a stainless steel plate (SUS304) that served as the gasket member's bonded object, and excellent hydrolysis resistance in high-temperature environments, despite the extremely harsh test conditions of 600 hours of standing in 120°C water (in a heat-resistant and pressure-resistant container).

[0122] As described above, the present disclosure provides the following aspects of the invention: Item 1. A gasket member comprising a laminate including at least a base layer and adhesive layers disposed on both sides of the base layer, wherein the adhesive layers contain a phenolic antioxidant that does not contain an ester group, or contain a phosphorus-based antioxidant and a phenolic antioxidant. Item 2. The gasket member according to Item 1, wherein the phenolic antioxidant that does not contain an ester group is a compound represented by the following general formula (C): [In general formula (C), R 1 represents an aliphatic hydrocarbon group, an aromatic group, an isocyanurate group, or the group: —CO—NR a -NR b -CO-, and R a and R b are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and R 2 is a methylene group or a carbonyl group, R 3 From R 7 At least one substituent is a hydroxyl group,3 From R 7 At least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms, 3 From R 7 wherein the substituent that is not a hydroxyl group or an aliphatic hydrocarbon group having 4 or more carbon atoms is a hydrogen atom, a methyl group, an ethyl group, or a propyl group, n is 2 or 3, m is 0 or 1, and p is 0 or 1.] Item 3. The gasket member according to Item 1 or 2, wherein the adhesive layer contains a phenolic antioxidant that does not contain an ester group. Item 4. The gasket member according to any one of Items 1 to 3, wherein the adhesive layer contains the phosphorus-based antioxidant. Item 5. The gasket member according to Item 4, wherein the phosphorus-based antioxidant is a compound represented by the following general formula (Aa) or the following general formula (Ab): [In general formula (Aa), R 11a and R 12aare each independently an alkyl group having 1 to 18 carbon atoms or a phenyl group which may have a substituent. In general formula (Ab), the groups Ar are each independently an aromatic group which may have a substituent. Item 6. The gasket member according to any one of Items 1 to 5, wherein the adhesive layer further contains a phenolic antioxidant containing an ester group. Item 7. The gasket member according to any one of Items 1 to 6, wherein the adhesive layer further contains a metal deactivator. Item 8. The gasket member according to any one of Items 1 to 7, wherein the base layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethylpentene, polyphenylene oxide, polyphenylene sulfide, fluororesin, and metal. Item 9. The gasket member according to any one of Items 1 to 8, wherein the base layer is a nonwoven fabric. Item 10. Item 14. A gasket member according to any one of Items 1 to 9, comprising an anchor coat layer on at least one surface side of the base material layer. Item 11. The gasket member according to any one of Items 1 to 10, wherein the thickness of the base material layer is 10 μm or more and 300 μm or less. Item 12. The gasket member according to any one of Items 1 to 11, wherein the thickness of each of the adhesive layers is 10 μm or more and 100 μm or less. Item 13. The gasket member according to any one of Items 1 to 12, wherein the glass transition temperature (Tg) of the resin forming the base material layer is 160°C or higher. Item 14. A method for manufacturing a gasket member constituted by a laminate comprising at least a base material layer and adhesive layers disposed on both sides of the base material layer, the method comprising a step of laminating the adhesive layers on both sides of the base material layer, wherein the adhesive layers contain a phenolic antioxidant not containing an ester group, or contain a phosphorus-based antioxidant and a phenolic antioxidant. Item 15. Item 16. A gasket comprising the gasket member according to any one of items 1 to 13. Item 16. An energy conversion device comprising the gasket according to item 15.

[0123] REFERENCE SIGNS LIST 1 substrate layer 2 adhesive layer 3 anchor coat layer 10 gasket member 11 opening

Claims

1. A gasket member comprising a laminate including at least a base layer and adhesive layers disposed on both sides of the base layer, the adhesive layers containing a phenolic antioxidant not containing an ester group, or containing a phosphorus-based antioxidant and a phenolic antioxidant.

2. The gasket member according to claim 1, wherein the phenolic antioxidant not containing an ester group is a compound represented by the following general formula (C): [In general formula (C), R 1 is an aliphatic hydrocarbon group, an aromatic group, an isocyanurate group, or a group: -CO-NR a -NR b -CO-, R a and R b are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; R 2 is a methylene group or a carbonyl group, R 3 From R 7 At least one of the substituents is a hydroxyl group; R 3 From R 7 At least one substituent adjacent to the hydroxyl group is an aliphatic hydrocarbon group having 4 or more carbon atoms, 3 From R 7 Among these, the substituents other than a hydroxyl group and an aliphatic hydrocarbon group having 4 or more carbon atoms are a hydrogen atom, a methyl group, an ethyl group, or a propyl group, n is 2 or 3, m is 0 or 1, and p is 0 or 1.

3. The gasket member according to claim 1 or 2, wherein the adhesive layer contains a phenolic antioxidant that does not contain an ester group.

4. The gasket member according to claim 1 or 2, wherein the adhesive layer contains the phosphorus-based antioxidant.

5. The gasket member according to claim 4, wherein the phosphorus-based antioxidant is a compound represented by the following general formula (Aa) or the following general formula (Ab): [In general formula (Aa), R 11a and R 12a are each independently an alkyl group having 1 to 18 carbon atoms or a phenyl group which may have a substituent. In general formula (Ab), each Ar group is independently an aromatic group which may have a substituent.

6. The gasket member according to claim 1 or 2, wherein the adhesive layer further contains a phenolic antioxidant containing an ester group.

7. The gasket member according to claim 1 or 2, wherein the adhesive layer further comprises a metal deactivator.

8. The gasket member according to claim 1 or 2, wherein the base layer contains at least one selected from the group consisting of polysulfone, polyethersulfone, polyphenylsulfone, polyarylate, polyolefin, polyamide, polyimide, polyetheretherketone, polymethylpentene, polyphenylene oxide, polyphenylene sulfide, fluororesin, and metal.

9. The gasket member according to claim 1 or 2, wherein the base material layer is a nonwoven fabric.

10. A gasket member according to claim 1 or 2, further comprising an anchor coat layer on at least one side of the surface of the base material layer.

11. The gasket member according to claim 1 or 2, wherein the thickness of the base layer is 10 μm or more and 300 μm or less.

12. The gasket member according to claim 1 or 2, wherein the thickness of each of the adhesive layers is 10 μm or more and 100 μm or less.

13. The gasket member according to claim 1 or 2, wherein the glass transition temperature (Tg) of the resin forming the base layer is 160° C. or higher.

14. A method for manufacturing 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, the method including a step of laminating the adhesive layers on both sides of the base material layer, the adhesive layers including a phenolic antioxidant not including an ester group, or including a phosphorus-based antioxidant and a phenolic antioxidant.

15. A gasket comprising the gasket member according to claim 1 or 2.

16. An energy conversion device comprising the gasket of claim 15.

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