Laminated film

Abstract

Provided is a laminated film comprising a substrate and a porous layer and having excellent durability despite comprising the porous layer.　A laminated film according to an embodiment of the present invention comprises a substrate and a porous layer, wherein the substrate and the porous layer are laminated with an adhesion layer interposed therebetween, and the porous layer and the adhesion layer each include at least one element selected from the group consisting of metal elements, metalloid elements, and carbon.

Description

Laminated Film

[0001] The present invention relates to a laminate film, more specifically to a laminate film including a substrate and a porous layer.

[0002] A laminate including a substrate and a porous layer can be used in various applications. For example, an electrode using a laminated catalyst having a porous structure and a substrate has been reported as an electrode for use in a water electrolysis device (for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2021-45709

[0004] However, conventional laminates having a porous layer tend to have poor durability.

[0005] An object of the present invention is to provide a laminated film that includes a substrate and a porous layer and that has excellent durability.

[0006] The present inventors have investigated the cause of the poor durability of conventional laminates having a porous layer. As a result, it has been found that in conventional laminates having a porous layer, the porous layer tends to peel off easily from the substrate, which tends to result in poor durability. As a result of further investigation, it has been found that the problem of the present invention can be solved by providing a specific layer between the substrate and the specific porous layer.

[0007] [1] A laminate film according to an embodiment of the present invention includes a substrate and a porous layer, the substrate and the porous layer being laminated via an adhesive layer, and the porous layer and the adhesive layer each containing at least one element selected from the group consisting of a metal element, a metalloid element, and carbon. [2] In the laminate film described in [1] above, the metal element may contain at least one element selected from the group consisting of a noble metal element and a base metal element. [3] In the laminate film described in [2] above, the noble metal element may contain at least one element selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and Au. [4] In the laminate film described in [2] or [3] above, the base metal element may contain at least one element selected from the group consisting of Mg, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ce, Pr, Ta, W, and Bi. [5] In the laminate film according to any one of [1] to [4] above, the metalloid element may include at least one selected from the group consisting of B, Si, Ge, and Sb. [6] In the laminate film according to any one of [1] to [5] above, the adhesive layer may include at least one selected from the group consisting of base metal elements, metalloid elements, and carbon. [7] In the laminate film according to any one of [1] to [6] above, the adhesive layer may have a thickness of 1 nm to 500 nm. [8] In the laminate film according to any one of [1] to [7] above, the porous layer may be formed by co-sputtering a first metal target with at least one selected from the group consisting of a second target and a second alloy target. [9] In the laminate film according to any one of [1] to [7] above, the porous layer may be formed by sputtering an alloy target.

[10] In the laminate film according to any one of the above items [1] to [9], the porous layer may be provided on both sides of the substrate.

[11] In the laminate film according to any one of the above items [1] to

[10] , the surface of the substrate facing the porous layer may contain a resin.

[0008] According to the present invention, it is possible to provide a laminate film that includes a substrate and a porous layer and has excellent durability.

[0009] [Terminology] In this specification, when the expression "weight" appears, it may be read as "mass," which is commonly used as an SI unit indicating weight, and vice versa.

[0010] 1. Laminated Film A laminated film according to an embodiment of the present invention includes a substrate and a porous layer, and the substrate and the porous layer are laminated via an adhesive layer. That is, the laminated film according to an embodiment of the present invention typically includes a laminate structure in which the substrate, the adhesive layer, and the porous layer are laminated in this order.

[0011] The laminated film according to an embodiment of the present invention may include any other appropriate layer as long as it includes a laminated structure in which a substrate, an adhesive layer, and a porous layer are laminated in this order, as long as the effects of the present invention are not impaired.

[0012] In one embodiment of the laminate film of the present invention, a porous layer is provided on only one side of a substrate. A typical example of the laminate film of the present invention according to such an embodiment is a laminate film in which a substrate, an adhesive layer, and a porous layer are laminated in this order.

[0013] Another embodiment of the laminate film of the present invention has a porous layer on both sides of the substrate. Typical examples of the laminate film of the present invention according to this embodiment include a laminate film in which a porous layer, an adhesive layer, a substrate, an adhesive layer, and a porous layer are laminated in this order, and a laminate film in which a porous layer, a substrate, an adhesive layer, and a porous layer are laminated in this order.

[0014] The total thickness of the laminate film of the present invention may be any appropriate thickness depending on the purpose, as long as the effects of the present invention are not impaired. The total thickness of the laminate film of the present invention may be, for example, 1 μm to 2000 μm, 50 μm to 1400 μm, 100 μm to 1000 μm, 130 μm to 600 μm, 150 μm to 500 μm, 150 μm to 300 μm, or 150 μm to 250 μm. For example, in an embodiment in which a porous layer is provided on only one side of the substrate, the total thickness of the laminate film of the present invention may be 1 μm to 1000 μm, 50 μm to 700 μm, 100 μm to 500 μm, 130 μm to 300 μm, or 150 μm to 250 μm.

[0015] <1-1. Substrate> Any appropriate substrate can be used as the substrate as long as it does not impair the effects of the present invention. The substrate may be composed of a single layer or may be a laminate of two or more layers.

[0016] The thickness of the substrate may be any appropriate thickness depending on the purpose as long as the effects of the present invention are not impaired. The thickness of the substrate is, for example, 1 μm to 1000 μm, or may be 50 μm to 700 μm, 100 μm to 500 μm, 130 μm to 300 μm, or 150 μm to 250 μm.

[0017] The substrate may be any appropriate material depending on the purpose, as long as the effect of the present invention is not impaired.

[0018] Examples of the substrate include resin substrates (e.g., polyethylene terephthalate (PET) substrates and polyimide (PI) substrates), composite substrates containing resin (e.g., Zirfon (registered trademark) manufactured by AGFA), metal substrates (e.g., Cu foil, Ti foil, Ti fibrous body (e.g., Pt-plated Ti fibrous body), Ni porous body), carbon composite materials (e.g., carbon paper, carbon paper on which MPL (Micro Porous Layer) is formed), cation exchange membranes (e.g., Nafion (registered trademark) and hydrocarbon-based electrolyte membranes), anion exchange membranes (e.g., polybenzimidazole (PBI) membranes), semiconductor substrates (e.g., silicon substrates), and glass substrates.

[0019] One embodiment of the substrate is an electrolyte membrane. Examples of electrolyte membranes include composite substrates containing resin (e.g., Zirfon (registered trademark) manufactured by AGFA), cation exchange membranes (e.g., Nafion (registered trademark) and hydrocarbon-based electrolyte membranes), and anion exchange membranes (e.g., polybenzimidazole (PBI) membranes). When the substrate is an electrolyte membrane, the laminate film according to an embodiment of the present invention may be a catalyst composite for water electrolysis (a laminate composite including a porous layer as a catalyst layer and an electrolyte membrane) or a catalyst composite for fuel cells (a laminate composite including a porous layer as a catalyst layer and an electrolyte membrane), and may be a catalyst composite for water electrolysis or a catalyst composite for fuel cells that has excellent durability. When the substrate is an electrolyte membrane, the laminate film according to an embodiment of the present invention may be a catalyst composite for CO electrolysis (e.g., for electrolytic synthesis of formic acid or synthetic fuels) (a laminate composite including a porous layer as a catalyst layer and an electrolyte membrane), and may be a catalyst composite for CO electrolysis that has excellent durability.

[0020] As one embodiment of the substrate, the surface on the porous layer side of the substrate may contain a resin. As the substrate of such an embodiment, any suitable substrate can be adopted as long as it contains a resin component on at least one surface, as long as the effects of the present invention are not impaired. In addition to the above-mentioned resin substrate, the substrate of such an embodiment includes, for example, the above-mentioned composite substrate containing a resin component on at least one surface, a MPL (Micro Porous Layer) composed of a resin formed on carbon paper, a cation exchange membrane containing a resin component on at least one surface, an anion exchange membrane containing a resin component on at least one surface, and a laminated substrate having a resin layer on at least one surface of a non-resin layer (such as a metal layer).

[0021] <1-2. Porous Layer> The thickness of the porous layer may be any appropriate thickness depending on the purpose, as long as the effects of the present invention are not impaired. The thickness of the porous layer is, for example, 1 nm to 3000 nm, or may be 10 nm to 2000 nm, 50 nm to 1500 nm, 100 nm to 1000 nm, or 200 nm to 800 nm.

[0022] The porous layer may be composed of one layer or may be a laminate of two or more layers.

[0023] The porous layer has a porous structure, which increases the surface area of ​​the porous layer and can provide various effects, such as increased gas diffusivity and high catalytic activity.

[0024] The porous layer contains at least one selected from the group consisting of a metal element, a metalloid element, and carbon. The porous layer may contain any other appropriate component as long as the effects of the present invention are not impaired.

[0025] Any appropriate metal element may be used as the metal element contained in the porous layer as long as the effects of the present invention are not impaired. The metal element may be one type only, or two or more types. When the porous layer contains two or more types of metal elements, the two or more types of metals may be an alloy.

[0026] The metal element typically includes at least one selected from the group consisting of a noble metal element and a base metal element. The noble metal element may be only one type, or two or more types. The base metal element may be only one type, or two or more types.

[0027] Any appropriate noble metal element may be used as long as it does not impair the effects of the present invention, such as at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and Au.

[0028] Any appropriate base metal element may be used as the base metal element as long as it does not impair the effects of the present invention. Examples of the base metal element include metal elements other than noble metal elements, and preferably at least one selected from the group consisting of Mg, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ce, Pr, Ta, W, and Bi.

[0029] As the metalloid element, any appropriate metalloid element can be used as long as it does not impair the effects of the present invention. Examples of the metalloid element include B, Si, Ge, As, Sb, and Te, and preferably at least one element selected from the group consisting of B, Si, Ge, and Sb.

[0030] The metal elements that can be contained in the porous layer include the eluted elements (for example, at least one selected from the group consisting of Al, Zn, Ag, and Sn) described below. However, as described below, when a porous layer having a porous structure is formed by treating a precursor layer containing an alloy of a eluted element that dissolves in a dealloying solution and at least one selected from the group consisting of a metal element other than the eluted element, a metalloid element, and carbon with a dealloying solution, the eluted elements contained in the precursor layer are eluted in the dealloying solution, so the content of the eluted elements in the formed porous layer is reduced. In this case, the content of the total of the eluted elements (preferably the total of Al, Zn, Ag, and Sn) in the porous layer may be, for example, less than 30 atomic weight%, may be less than 25 atomic weight%, may be less than 20 atomic weight%, may be less than 16 atomic weight%, may be 15 atomic weight% or less, may be 12 atomic weight% or less, may be 10 atomic weight% or less, may be 8 atomic weight% or less, may be 6 atomic weight% or less, may be 4 atomic weight% or less, may be 2 atomic weight% or less, may be 1 atomic weight% or less, may be 0.1 atomic weight% or less, or may be substantially 0 atomic weight%.

[0031] The porous layer can be formed by any appropriate method as long as it does not impair the effects of the present invention. To further enhance the effects of the present invention, the porous layer can be formed, for example, by a dealloying method. Specifically, the porous layer can be formed by treating a precursor layer containing an alloy of a leachable element that dissolves in a dealloying solution and at least one element selected from the group consisting of a metal element, a metalloid element, and carbon other than the leachable element, with a dealloying solution. By the dealloying method, the leachable element contained in the precursor layer is dissolved into the dealloying solution, forming the porous layer.

[0032] [1-2-a. Precursor Layer] The precursor layer typically contains an alloy of a leachable element and at least one selected from the group consisting of a metal element other than the leachable element, a metalloid element, and carbon. Note that the term "alloy" as used herein also includes alloy steel (an alloy of a leachable element and a metalloid element, an alloy of a leachable element and carbon, or an alloy of a leachable element, a metalloid element, and carbon). The leachable element may be of only one type, or two or more types. The metal element other than the leachable element may be of only one type, or two or more types. The metalloid element may be of only one type, or two or more types.

[0033] When the precursor layer contains an alloy of a leachable element and at least one selected from the group consisting of a metal element other than the leachable element, a metalloid element, and carbon, the content ratio of the leachable element to the at least one selected from the group consisting of a metal element other than the leachable element, a metalloid element, and carbon in the precursor layer, expressed as atomic weight percent (at %) of [leachable element]:[total of metal elements other than the leachable element, metalloid element, and carbon], may be, for example, 30:70 to 99.9:0.1, alternatively, 50:50 to 99:1, 60:40 to 98:2, 70:30 to 97:3, 75:25 to 96:4, or 80:20 to 95:5, in terms of atomic weight percent (at %).

[0034] Examples of the eluting element include elements that dissolve in a dealloying solution during alloy dealloying. In order to further enhance the effects of the present invention, the eluting element is preferably at least one element selected from the group consisting of Al, Zn, Ag, and Sn. Therefore, the precursor layer preferably contains an alloy of at least one eluting element selected from the group consisting of Al, Zn, Ag, and Sn and at least one element selected from the group consisting of a metal element, a metalloid element, and carbon other than the eluting element.

[0035] Examples of metal elements other than the eluted elements include at least one selected from the group consisting of Mg, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ce, Pr, Ta, W, Os, Ir, Pt, Au, and Bi.

[0036] The precursor layer can be formed by any appropriate method as long as the effects of the present invention are not impaired. For example, the precursor layer is formed by a vacuum film formation method, specifically, by vapor deposition or sputtering.

[0037] Examples of the formation by sputtering include co-sputtering using a plurality of targets (sometimes referred to as simultaneous sputtering) and sputtering using an alloy target.

[0038] Any appropriate sputtering conditions may be adopted as long as they do not impair the effects of the present invention. The atmosphere during sputtering may be, for example, a rare gas atmosphere such as argon. The pressure during sputtering may be, for example, 0.1 Pa to 10 Pa. Examples of the discharge method for sputtering include DC discharge, RF discharge, and MF-AC discharge. The sputtering temperature may be set to any appropriate temperature depending on the type of substrate, etc. The sputtering temperature may be, for example, -10°C to 150°C (e.g., sputtering onto a PET substrate), -10°C to 500°C (e.g., sputtering onto a PI substrate), or -10°C to 1000°C (e.g., sputtering onto a metal substrate).

[0039] In an embodiment in which the precursor layer is formed by co-sputtering, the precursor layer is formed, for example, by co-sputtering a first metal target with at least one selected from the group consisting of a second target and a second alloy target.

[0040] The first metal target may be, for example, an eluted element. The first metal target may be one type or two or more types.

[0041] The second target may be, for example, at least one selected from the group consisting of metal elements other than the eluted elements, metalloid elements, and carbon. The second target may be of only one type, or of two or more types.

[0042] The second alloy target may be, for example, an alloy composed of at least two elements selected from the group consisting of metal elements other than the eluted elements, metalloid elements, and carbon. The second alloy target may be of only one type, or of two or more types.

[0043] In an embodiment in which the precursor layer is formed by co-sputtering, the first metal target, the second target, and the second alloy target may be selected and the sputtering conditions may be set as appropriate, for example, as described above, so that the content ratio of the eluted element in the resulting precursor layer to at least one element selected from the group consisting of metal elements other than the eluted element, metalloid elements, and carbon falls within the aforementioned range in atomic weight percentage (at %) of [eluted element]:[total of metal elements other than the eluted element, metalloid elements, and carbon].

[0044] In an embodiment in which the precursor layer is formed by sputtering an alloy target, the alloy target may be, for example, an alloy composed of a leaching element and at least one element selected from the group consisting of a metal element other than the leaching element, a metalloid element, and carbon. The alloy target may be of only one type, or of two or more types.

[0045] In an embodiment in which the precursor layer is formed by sputtering an alloy target, the alloy target may be selected and the sputtering conditions may be set as appropriate, for example, as described above, so that the content ratio of the eluted element in the resulting precursor layer to at least one element selected from the group consisting of metal elements other than the eluted element, metalloid elements, and carbon falls within the aforementioned range in terms of the atomic ratio (at %) of [eluted element]:[total of metal elements other than the eluted element, metalloid elements, and carbon].

[0046] When forming the precursor layer, film formation by sputtering may be performed multiple times for the purpose of adjusting the thickness (especially, adjusting to increase the thickness), etc. Furthermore, the number of targets may be increased for the purpose of adjusting the thickness (especially, adjusting to increase the thickness), etc.

[0047] [1-2-b. Dealloying Method] The porous layer can be formed, for example, by a dealloying method. For example, the porous layer can be formed by treating the precursor layer with a dealloying solution. This dealloying method allows eluted elements contained in the precursor layer to be dissolved into the dealloying solution, thereby forming the porous layer. Any appropriate conditions for the dealloying method can be adopted as long as the treatment with the dealloying solution can be performed at an appropriate temperature, as long as the effects of the present invention are not impaired.

[0048] The dealloying solution for treating the precursor layer may be, for example, any suitable acidic, alkaline, or neutral solution that can be used in a dealloying method. The concentration of the dealloying solution may be any suitable concentration depending on the purpose.

[0049] Examples of the acidic solution include an aqueous solution of hydrochloric acid, an aqueous solution of nitric acid, an aqueous solution of sulfuric acid, an aqueous solution of phosphoric acid, an aqueous solution of acetic acid, and a mixture thereof. Examples of the alkaline solution include an aqueous solution of sodium hydroxide and an aqueous solution of potassium hydroxide.

[0050] The treatment temperature in the dealloying method is, for example, 5° C. or higher, and may be 10° C. or higher, 20° C. or higher, 30° C. or higher, 40° C. or higher, 50° C. or higher, 60° C. or higher, 70° C. or higher, 80° C. or higher, 90° C. or higher, or 100° C. The upper limit of the treatment temperature in the dealloying method is, for example, less than 300° C.

[0051] In the dealloying method, the treatment with the dealloying solution may be carried out under normal pressure or under pressure. As a method for carrying out the treatment under pressure, any appropriate pressurizing method may be adopted as long as it does not impair the effects of the present invention. Such a pressurizing method may, for example, be pressurizing in a pressure-resistant vessel such as an autoclave.

[0052] <1-3. Adhesion layer> In the laminate film according to the embodiment of the present invention, the substrate and the porous layer are laminated via a specific adhesion layer. By having such a specific adhesion layer, the laminate film according to the embodiment of the present invention can further exhibit the effects of the present invention and can provide a laminate film that is excellent in durability even though it has a porous layer.

[0053] The thickness of the adhesive layer may be any appropriate total thickness as long as it does not impair the effects of the present invention. In terms of further exhibiting the effects of the present invention, the thickness of the adhesive layer is, for example, 1 nm to 1000 nm, or may be 1 nm to 500 nm, 2 nm to 500 nm, 3 nm to 500 nm, 4 nm to 500 nm, 5 nm to 500 nm, 5 nm to 300 nm, or 5 nm to 200 nm.

[0054] The adhesive layer may be made of one layer or may be a laminate of two or more layers.

[0055] The adhesive layer contains at least one selected from the group consisting of a metal element, a metalloid element, and carbon. The adhesive layer may contain any other appropriate component as long as the effects of the present invention are not impaired.

[0056] As the metal element that can be contained in the adhesive layer, any appropriate metal element can be adopted as long as the effects of the present invention are not impaired. The metal element may be only one type, or may be two or more types. When the adhesive layer contains two or more types of metal elements, the two or more types of metals may be an alloy.

[0057] The metal element typically includes at least one selected from the group consisting of a noble metal element and a base metal element. The noble metal element may be only one type, or two or more types. The base metal element may be only one type, or two or more types.

[0058] Any appropriate noble metal element may be used as long as it does not impair the effects of the present invention, such as at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and Au.

[0059] Any appropriate base metal element may be used as the base metal element as long as it does not impair the effects of the present invention. Examples of the base metal element include metal elements other than noble metal elements, and preferably at least one selected from the group consisting of Mg, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ce, Pr, Ta, W, and Bi.

[0060] As the metalloid element, any appropriate metalloid element can be used as long as it does not impair the effects of the present invention. Examples of the metalloid element include B, Si, Ge, As, Sb, and Te, and preferably at least one element selected from the group consisting of B, Si, Ge, and Sb.

[0061] In one preferred embodiment, the adhesion layer contains at least one selected from the group consisting of a base metal element, a metalloid element, and carbon. In this embodiment, the adhesion layer does not necessarily contain a noble metal element.

[0062] In the laminate film according to an embodiment of the present invention, when a resin substrate (such as a polyethylene terephthalate (PET) substrate) is used as the substrate, it is a preferred embodiment that the adhesion layer contains at least one selected from the group consisting of base metal elements, semi-metal elements, and carbon, in order to further demonstrate the effects of the present invention. On the other hand, in the laminate film according to an embodiment of the present invention, when carbon paper or carbon paper with an MPL (Micro Porous Layer) formed thereon is used as the substrate, the adhesion layer may contain a precious metal element, and therefore it is a preferred embodiment that the adhesion layer contains at least one selected from the group consisting of metal elements (noble metal elements and base metal elements), semi-metal elements, and carbon, in order to further demonstrate the effects of the present invention.

[0063] In the laminate film according to an embodiment of the present invention, when an electrolyte membrane (e.g., Zirfon®) having a high surface roughness (e.g., greater than the thickness of the adhesion layer) is used as the substrate, it is preferable that at least one of the following conditions be satisfied: the adhesion layer contains Ni; and the adhesion layer has a thickness of 10 nm or more, in order to further improve durability and catalytic activity. It is more preferable that the adhesion layer contains Ni and the adhesion layer has a thickness of 10 nm or more. The thickness of the adhesion layer may be 10 nm to 1000 nm, 15 nm to 500 nm, 20 nm to 400 nm, 25 nm to 300 nm, 28 nm to 200 nm, or 30 nm to 100 nm. When an electrolyte membrane having a high surface roughness, such as Zirfon®, is used as the substrate, the difficulty of ion migration in the electrolyte can be suppressed even if the adhesion layer is made thick to a certain extent. On the other hand, when an electrolyte membrane with a small surface roughness such as Nafion (registered trademark) or an anion exchange membrane (PBI, etc.) is used, if the thickness of the adhesion layer is made large to a certain extent, it may become difficult for ions in the electrolyte to move.

[0064] The adhesion layer can be formed by any appropriate method as long as the effects of the present invention are not impaired. The adhesion layer is typically formed by a vacuum film formation method, for example, by vapor deposition or sputtering.

[0065] Formation by sputtering includes, for example, single target sputtering, co-sputtering (sometimes referred to as simultaneous sputtering), and alloy target sputtering.

[0066] Any appropriate sputtering conditions may be adopted as long as they do not impair the effects of the present invention. The atmosphere during sputtering may be, for example, a rare gas atmosphere such as argon. The pressure during sputtering may be, for example, 0.1 Pa to 10 Pa. Examples of the discharge method for sputtering include DC discharge, RF discharge, and MF-AC discharge. The sputtering temperature may be set to any appropriate temperature depending on the type of substrate, etc. The sputtering temperature may be, for example, -10°C to 150°C (e.g., sputtering onto a PET substrate), -10°C to 500°C (e.g., sputtering onto a PI substrate), or -10°C to 1000°C (e.g., sputtering onto a metal substrate).

[0067] Before sputtering, the sputtering target (typically a substrate) may be cleaned by subjecting it to a plasma treatment, such as ion bombardment. Any appropriate conditions for the plasma treatment may be adopted as long as the effects of the present invention are not impaired.

[0068] 2. Uses of Laminate Films Because laminate films according to embodiments of the present invention have excellent durability, they can be used in a variety of applications, including optical applications (e.g., refractive index control members), catalyst applications (e.g., catalyst composites for water electrolysis (laminate composites including a porous layer as a catalyst layer and an electrolyte membrane), catalyst composites for fuel cells (laminate composites including a porous layer as a catalyst layer and an electrolyte membrane), catalyst composites for CO electrolysis (e.g., for electrolytic synthesis of formic acid or synthetic fuels) (laminate composites including a porous layer as a catalyst layer and an electrolyte membrane)), thermocompression bonding (thermal lamination), and membrane applications (e.g., water evaporation promotion membranes). In particular, because the porous layer can function as a catalyst layer, laminate films according to embodiments of the present invention are suitable for use in catalyst composites for water electrolysis and catalyst composites for fuel cells.

[0069] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The test and evaluation methods used in the examples are as follows.

[0070] <Thickness of Layer Formed by Sputtering> The thickness of the layer formed by sputtering each element onto the glass substrate was calculated using a stylus film thickness step meter (Dektak, manufactured by Bruker). Based on the obtained layer thickness of each element and the elemental composition of the layer actually formed by sputtering, the thickness of the layer formed by sputtering was calculated, and this calculated thickness was defined as the thickness of the layer formed by sputtering.

[0071] <Evaluation of the Presence or Absence of Peeling of Porous Layer from Substrate (Durability Evaluation)> The obtained laminated film was visually inspected to see whether or not the porous layer had peeled from the substrate, and evaluated according to the following criteria: ◯: No peeling was observed. Δ: Spot-like peeling was observed in some areas. ×: Peeling was observed throughout the film.

[0072] <Surface Observation of Porous Layer (Evaluation of Presence or Absence of Porous Structure)> The surface of the porous layer was observed using an FE-SEM (manufactured by Hitachi High-Tech Corporation, product name "SU8220"). During surface observation, the presence or absence of a porous structure was confirmed at an acceleration voltage of 2 kV, a WD of 4 mm, and a magnification of 100,000x, while the observation surface was in contact with the substrate holder using conductive tape to prevent surface charge-up. Furthermore, when the pore diameter was small and it was difficult to determine the presence or absence of a porous structure by surface observation, a FE-TEM (manufactured by JEOL Ltd., JEM-2800) was used to observe the cross section of the porous layer. The cross section was prepared using an FIB microsampling method (manufactured by Hitachi High-Tech Corporation, FB2200), and FE-TEM analysis was performed. The presence or absence of a porous structure was confirmed using the FE-TEM at an acceleration voltage of 200 kV and a magnification of 1,000,000x. Evaluation was based on the following criteria: ∘: Pores were recognizable based on the difference in brightness. ×: No difference in brightness was observed and the holes were not recognizable.

[0073] <Constant Current Durability Test> A constant current durability test (CP test) was conducted under the following conditions. Electrolytic cell: A PFA container was used. Reference electrode: Hydroflex (registered trademark) was connected via a Luggin capillary. Counter electrode: Platinum (Pt) coil. Working electrode: Resin plate electrode manufactured by EC Frontier (product number: AE-7). Electrolyte: 1 M KOH aqueous solution. Electrolyte temperature: 30°C. Bubbling: Degassed with nitrogen (N2) gas for 30 minutes or more. Stirring conditions: Stirred at 300 rpm using a rotor. Measurements were conducted according to the following procedure. 1. It was confirmed that the potential was stable at the open circuit potential (OCV). 2. In the constant current test (CP test), a current of -30 mA / cm was used. 2 3. If the measurement does not stop after 30 minutes, the test was carried out under a constant current condition of -120 mA / cm 2 , -270mA / cm 2 The current value was increased stepwise, and the test was carried out continuously under each condition. 4. The potential change under each current condition was recorded and used as an evaluation index for the constant current durability test. The evaluation criteria were as follows: ◯: Measurement did not stop for 30 minutes. △: Measurement did not stop for 15 minutes or more, but stopped in less than 30 minutes. ×: Measurement stopped in less than 15 minutes.

[0074] <Potential Measurement at -10 mA by LSV Measurement> Potential measurement at -10 mA by LSV measurement was carried out under the same measurement environment as the constant current test (CP test), and the measurement was carried out according to the following procedure. 1. It was confirmed that the potential was stable at the open circuit potential (OCV). 2. A sweep from 0 V to -1 V was carried out by linear sweep voltammetry (LSV) to measure the overpotential on the cathode side. 3. The solution resistance was obtained by electrochemical impedance measurement (EIS). 4. Based on the obtained solution resistance value, iR correction (correction for voltage drop due to current passing through the electrolyte and electrodes) was carried out. 5. From the current-potential characteristics (IV characteristics) after iR correction, -10 mA / cm 2 The potential at this point was evaluated and used as an index of catalytic activity.

[0075] <Abbreviations of substrates in examples and comparative examples> PET: polyethylene terephthalate substrate, manufactured by Toyobo Co., Ltd., trade name "A4160", thickness = 188 μm PI: polyimide substrate, manufactured by Xenomax Japan Co., Ltd., trade name "XENOMAX", thickness = 38 μm Ni porous body: thickness = 0.3 mm (300 μm) Zirfon: manufactured by AGFA, trade name "Zirfon (registered trademark)", product number: UTP500, thickness = 500 μm Cu foil: manufactured by Fukuda Metal Foil & Powder Co., Ltd., thickness = 18 μm Ti foil: manufactured by Nilaco Corporation, thickness = 50 μm Carbon paper and carbon paper + MPL: manufactured by Mitsubishi Chemical Corporation Nafion: manufactured by Chemours Corporation, trade name "Nafion (registered trademark)", thickness = 180 μm Glass: thickness = 0.5 mm (500 μm)

[0076] <Abbreviations of sputtering targets for adhesion layers in Examples and Comparative Examples> Cr: Cr target Ni: Ni target Zr: Zr target Fe: Fe target Cu: Cu target Ti: Ti target Pd: Pd target Pt: Pt target Ir: Ir target NiS: NiS target

[0077] <Abbreviations for sputtering targets of precursor layer in Examples and Comparative Examples> Ni10-Al90 (at%): Ni-Al alloy target, Ni:Al=10:90 (atomic weight % ratio) Ni12-Al88 (at%): Ni-Al alloy target, Ni:Al=12:88 (atomic weight % ratio) Ni24-Al76 (at%): Ni-Al alloy target, Ni:Al=24:76 (atomic weight % ratio) Ni10 (at%) + Al90 (at%): Co-sputtering of Ni target and Al target (Ni:Al=10:90 (atomic weight % ratio)) Au15 (at%) + Al85 (at%): Co-sputtering of Au target and Al target (Au:Al=15:85 (atomic weight % ratio)) Ni39 (at%) + Zn61 (at%): Co-sputtering of Ni target and Zn target (Ni:Zn = 39:61 (atomic weight %)) Fe10 (at%) + Al90 (at%): Co-sputtering of Fe target and Al target (Fe:Al = 10:90 (atomic weight %)) Cu10 (at%) + Al90 (at%): Co-sputtering of Cu target and Al target (Cu:Al = 10:90 (atomic weight %)) Pt10 (at%) + Al90 (at%): Co-sputtering of Pt target and Al target (Pt:Al = 10:90 (atomic weight %)) Pt6 (at%) + Al94 (at%): Co-sputtering of Pt target and Al target (Pt:Al = 6:94 (atomic weight %)) Pd10 (at%) + Al90 (at%): Co-sputtering of Pd target and Al target (Pd:Al = 10:90 (atomic weight %)) Ni-Fe10 (at%) + Al90 (at%): Co-sputtering of Ni-Fe alloy target (Ni:Fe = 50:50, atomic weight %) and Al target (Ni-Fe:Al = 10:90 (atomic weight %)) Ir25 (at%) + Al75 (at%): Co-sputtering of Ir target and Al target (Ir:Al = 25:75 (atomic weight %)) Ir20 (at%) + Al80 (at%): Co-sputtering of Ir target and Al target (Ir:Al = 20:80 (atomic weight %)) Ir10 (at%) + Al90 (at%): Co-sputtering of an Ir target and an Al target (Ir:Al = 10:90 (atomic weight ratio))NiS10 (at%) + Al90 (at%): Co-sputtering of NiS target and Al target (NiS:Al = 10:90 (atomic weight %))

[0078] <Abbreviations for dealloying solutions in Examples and Comparative Examples> NaOHaq: 0.5M NaOH aqueous solution HClaq: 0.5M HCl aqueous solution Phosphoric acid + acetic acid: mixed aqueous solution of phosphoric acid and acetic acid HNO3aq: 1 wt% HNO3 aqueous solution

[0079] [Example 1] A PET substrate was prepared as a substrate. A multi-target simultaneous sputtering device (2-inch specification) was used. First, the substrate was introduced into the device, and the pressure was increased to 5.0 × 10 -4 After confirming that the pressure was below 1 Pa, the substrate was cleaned by reverse sputtering. Reverse sputtering was performed at room temperature (23 ° C.) in an Ar gas atmosphere at 0.4 Pa, 30 W, and 60 seconds. Next, a Cr target was used as the sputtering target, and a film was formed at room temperature (23 ° C.) under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 3 nm, forming an adhesion layer. Next, a Ni-Al alloy target (Ni:Al = 10:90 (atomic weight %)) was used as the sputtering target, and a film was formed at room temperature (23 ° C.) under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 500 nm, forming a precursor layer. The obtained laminate was immersed in a 0.5 M NaOH aqueous solution as a dealloying solution and left to stand at room temperature (23 ° C.) for 10 minutes to perform a dealloying treatment, and the eluted element Al was dissolved into the dealloying solution. After the dealloying treatment, the sample was immersed in ion-exchanged water and left to stand for 3 minutes, which was repeated twice for cleaning, and then thoroughly dried naturally in the air. The results are shown in Table 1.

[0080] Example 2 The same procedure as in Example 1 was carried out, except that the adhesion layer was formed to a thickness of 5 nm as shown in Table 1. The results are shown in Table 1.

[0081] Example 3 The same procedure as in Example 1 was carried out, except that the adhesive layer was formed to a thickness of 50 nm as shown in Table 1. The results are shown in Table 1.

[0082] Example 4 The same procedure as in Example 3 was carried out except that a PI substrate was used as the substrate, as shown in Table 1. The results are shown in Table 1.

[0083] Example 5 The procedure was the same as in Example 3, except that the precursor layer was formed by co-sputtering using a Ni target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with a Ni:Al ratio of 10:90 (atomic weight %) and a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0084] Example 6 The procedure was the same as in Example 3, except that the precursor layer was formed by co-sputtering using an Au target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with an Au:Al ratio of 15:85 (atomic weight %), to a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0085] Example 7 The same procedure as in Example 6 was carried out, except that the dealloying solution was changed to a mixed aqueous solution of phosphoric acid and acetic acid, as shown in Table 1. The results are shown in Table 1.

[0086] Example 8 The same procedure as in Example 1 was carried out, except that the adhesion layer was formed using a Ni target as the sputtering target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23° C.) so that the film thickness would be 5 nm, as shown in Table 1. The results are shown in Table 1.

[0087] Example 9 The same procedure as in Example 8 was carried out, except that a Ni porous body was used as the substrate, and a precursor layer was formed by co-sputtering using a Ni target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with a Ni:Al ratio of 10:90 (atomic weight %), to a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0088] Example 10 The same procedure as in Example 8 was carried out, except that Zirfon was used as the substrate, as shown in Table 1. The results are shown in Table 1. The results of the constant current durability test and the potential measured at -10 mA by LSV measurement are shown in Table 2.

[0089] Example 11 The same procedure as in Example 8 was carried out, except that the adhesive layer was formed to a thickness of 50 nm as shown in Table 1. The results are shown in Table 1.

[0090] Example 12 The procedure was the same as in Example 11, except that the precursor layer was formed by co-sputtering using a Ni target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with a Ni:Al ratio of 10:90 (atomic weight %) and a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0091] Example 13 As shown in Table 1, a precursor layer was formed by co-sputtering at room temperature (23°C) using a Ni target and a Zn target as sputtering targets under an Ar gas atmosphere at a pressure of 0.3 Pa, with a Ni:Zn ratio of 39:61 (atomic weight percentage) and a thickness of 500 nm, and the procedure was the same as in Example 11, except that the dealloying solution was changed to a 0.5 M HCl aqueous solution. The results are shown in Table 1.

[0092] Example 14 The same procedure as in Example 1 was carried out, except that the adhesion layer was formed using a Zr target as the sputtering target in an Ar gas atmosphere at a pressure of 0.3 Pa and at room temperature (23° C.) so that the film thickness would be 50 nm, as shown in Table 1. The results are shown in Table 1.

[0093] Example 15 The same procedure as in Example 14 was carried out, except that Zirfon was used as the substrate, as shown in Table 1. The results are shown in Table 1. The results of the constant current durability test and the potential measured at -10 mA by LSV measurement are shown in Table 2.

[0094] Example 16 As shown in Table 1, the adhesion layer was formed by sputtering an Fe target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) to a thickness of 50 nm, and the precursor layer was formed by co-sputtering an Fe target and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa with an Fe:Al ratio of 10:90 (atomic weight %) at room temperature (23°C) to a thickness of 500 nm, except that the same procedures were carried out as in Example 1. The results are shown in Table 1.

[0095] Example 17 The same procedures as in Example 1 were carried out, except that, as shown in Table 1, a Cu foil was used as the substrate, the adhesion layer was formed by sputtering a Cu target under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 5 nm at room temperature (23°C), and the precursor layer was formed by co-sputtering a Cu target and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa with a Cu:Al ratio of 10:90 (atomic weight ratio) to a thickness of 500 nm at room temperature (23°C). The results are shown in Table 1.

[0096] Example 18 The same procedures as in Example 1 were carried out except that, as shown in Table 1, the adhesion layer was formed by sputtering a Ti target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23° C.) to a thickness of 5 nm, and the precursor layer was formed by co-sputtering a Pt target and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa with a Pt:Al ratio of 6:94 (atomic weight %) to a thickness of 500 nm at room temperature (23° C.). The results are shown in Table 1.

[0097] Example 19 The same procedure as in Example 18 was carried out, except that carbon paper was used as the substrate, as shown in Table 1. The results are shown in Table 1.

[0098] [Example 20] The same procedure as in Example 18 was carried out, except that carbon paper + MPL was used as the substrate, as shown in Table 1. The results are shown in Table 1.

[0099] Example 21 The same procedures as in Example 1 were carried out except that, as shown in Table 1, the adhesion layer was formed by using a Pd target as the sputtering target and depositing the film at room temperature (23°C) in an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 50 nm, and the precursor layer was formed by co-sputtering using a Pd target and an Al target as the sputtering targets and depositing the film at room temperature (23°C) in an Ar gas atmosphere at a pressure of 0.3 Pa with a Pd:Al ratio of 10:90 (atomic weight %) to a thickness of 500 nm. The results are shown in Table 1.

[0100] Example 22 The same procedures as in Example 1 were carried out except that, as shown in Table 1, the adhesion layer was formed by sputtering using a Pt target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) to a thickness of 50 nm, and the precursor layer was formed by co-sputtering using a Pt target and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa with a Pt:Al ratio of 6:94 (atomic weight %) to a thickness of 500 nm at room temperature (23°C). The results are shown in Table 1.

[0101] Example 23 The same procedure as in Example 22 was carried out, except that carbon paper was used as the substrate, as shown in Table 1. The results are shown in Table 1.

[0102] Example 24 The same procedure as in Example 22 was carried out, except that carbon paper and MPL were used as the substrate, as shown in Table 1. The results are shown in Table 1.

[0103] Example 25 The same procedure as in Example 10 was carried out, except that the adhesion layer was formed using a Cr target as the sputtering target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23° C.) so that the film thickness would be 100 nm, as shown in Table 1. The results are shown in Table 1.

[0104] Example 26 As shown in Table 1, the adhesion layer was formed by sputtering a Cr target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) to a thickness of 5 nm, and the precursor layer was formed by co-sputtering a Ni-Fe alloy target (Ni:Fe = 50:50) (atomic weight ratio) and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) to a thickness of 100 nm, except that the same procedures were carried out as in Example 4. The results are shown in Table 1.

[0105] Example 27 The procedure was the same as in Example 4, except that the precursor layer was formed using a Ni-Al alloy target (Ni:Al=24:76 (atomic weight ratio)) as the sputtering target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23° C.) so that the film thickness would be 500 nm, as shown in Table 1. The results are shown in Table 1.

[0106] Example 28 The procedure was the same as in Example 5, except that the precursor layer was formed by co-sputtering using an Ir target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with an Ir:Al ratio of 25:75 (atomic weight %), to a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0107] Example 29 The same procedures as in Example 1 were carried out, except that, as shown in Table 1, a Ti foil was used as the substrate, an adhesion layer was formed by sputtering using an Ir target as the sputtering target at room temperature (23°C) under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 50 nm, and a precursor layer was formed by co-sputtering using an Ir target and an Al target as the sputtering targets at room temperature (23°C) under an Ar gas atmosphere at a pressure of 0.3 Pa with an Ir:Al ratio of 20:80 (atomic weight ratio) to a thickness of 500 nm. The results are shown in Table 1.

[0108] Example 30 As shown in Table 1, the adhesion layer was formed by using a NiS target as the sputtering target and depositing the film at room temperature (23°C) in an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 50 nm, and the precursor layer was formed by co-sputtering using a NiS target and an Al target as the sputtering targets and depositing the film at room temperature (23°C) in an Ar gas atmosphere at a pressure of 0.3 Pa with a NiS:Al ratio of 10:90 (atomic weight %) to a thickness of 500 nm, except that the same procedures were carried out as in Example 1. The results are shown in Table 1.

[0109] Example 31 The same procedures as in Example 1 were carried out, except that, as shown in Table 1, Nafion was used as the substrate, the adhesion layer was formed by sputtering using an Ir target as the sputtering target at room temperature (23°C) under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 10 nm, and the precursor layer was formed by co-sputtering using an Ir target and an Al target as the sputtering targets at room temperature (23°C) under an Ar gas atmosphere at a pressure of 0.3 Pa with an Ir:Al ratio of 10:90 (atomic weight ratio) to a thickness of 500 nm. The results are shown in Table 1.

[0110] Example 32 The same procedures as in Example 1 were carried out, except that, as shown in Table 1, glass was used as the substrate, the adhesion layer was formed by sputtering a Cr target under an Ar gas atmosphere at a pressure of 0.3 Pa to a thickness of 10 nm at room temperature (23°C), and the precursor layer was formed by co-sputtering a Pt target and an Al target under an Ar gas atmosphere at a pressure of 0.3 Pa with a Pt:Al ratio of 10:90 (atomic weight ratio) to a thickness of 500 nm at room temperature (23°C). The results are shown in Table 1.

[0111] Example 33 The same procedure as in Example 15 was carried out, except that the adhesion layer was formed using a Ni target as the sputtering target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) so that the film thickness would be 50 nm, as shown in Table 1. The results are shown in Table 1. The results of the constant current durability test and the potential measured at -10 mA by LSV measurement are also shown in Table 2.

[0112] Example 34 The same procedure as in Example 15 was carried out, except that the adhesion layer was formed using a Ni target as the sputtering target in an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) so that the film thickness would be 25 nm, as shown in Table 1. The results are shown in Table 1. The results of the constant current durability test and the potential measured at -10 mA by LSV measurement are also shown in Table 2.

[0113] Example 35 The same procedure as in Example 15 was carried out, except that the adhesion layer was formed using a Cr target as the sputtering target under an Ar gas atmosphere at a pressure of 0.3 Pa at room temperature (23°C) so as to have a film thickness of 50 nm, as shown in Table 1. The results are shown in Table 1. The results of the constant current durability test and the potential measured at -10 mA by LSV measurement are also shown in Table 2.

[0114] Comparative Example 1 As shown in Table 1, the same procedure as in Example 1 was carried out except that no adhesive layer was provided. The results are shown in Table 1.

[0115] Comparative Example 2 The same procedure as in Example 21 was carried out except that no adhesive layer was provided, as shown in Table 1. The results are shown in Table 1.

[0116] Comparative Example 3 The same procedure as in Example 1 was carried out, except that no adhesion layer was provided and the precursor layer was formed by co-sputtering using a Pt target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with a Pt:Al ratio of 10:90 (atomic weight %) and a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0117] Comparative Example 4 The procedure was the same as in Example 1, except that no adhesion layer was provided and the precursor layer was formed by co-sputtering using a Cu target and an Al target as sputtering targets at room temperature (23° C.) in an Ar gas atmosphere at a pressure of 0.3 Pa, with a Cu:Al ratio of 10:90 (atomic weight %) and a thickness of 500 nm, as shown in Table 1. The results are shown in Table 1.

[0118]

[0119]

[0120] The laminated film according to the embodiment of the present invention can be used in a variety of applications, including optical applications (e.g., refractive index control members), catalyst applications (e.g., catalyst composites for water electrolysis (laminated composites including a porous layer as a catalyst layer and an electrolyte membrane), catalyst composites for fuel cells (laminated composites including a porous layer as a catalyst layer and an electrolyte membrane), catalyst composites for CO electrolysis (e.g., for electrolytic synthesis of formic acid or synthetic fuels) (laminated composites including a porous layer as a catalyst layer and an electrolyte membrane)), thermocompression bonding (thermal lamination) applications, and membrane applications (e.g., water evaporation promotion membranes).

Claims

1. A laminated film comprising a substrate and a porous layer, the substrate and the porous layer being laminated via an adhesive layer, and the porous layer and the adhesive layer each containing at least one element selected from the group consisting of a metal element, a metalloid element, and carbon.

2. The laminated film according to claim 1, wherein the metal element comprises at least one selected from the group consisting of noble metal elements and base metal elements.

3. The laminate film according to claim 2, wherein the noble metal element comprises at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and Au.

4. The laminate film according to claim 2, wherein the base metal element comprises at least one selected from the group consisting of Mg, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ce, Pr, Ta, W, and Bi.

5. The laminate film according to claim 1, wherein the metalloid element comprises at least one element selected from the group consisting of B, Si, Ge, and Sb.

6. The laminated film according to claim 1, wherein the adhesive layer contains at least one element selected from the group consisting of base metal elements, semi-metal elements, and carbon.

7. The laminated film according to claim 1, wherein the adhesive layer has a thickness of 1 nm to 500 nm.

8. The laminated film according to claim 1, wherein the porous layer is formed by co-sputtering a first metal target with at least one target selected from the group consisting of a second target and a second alloy target.

9. The laminated film according to claim 1, wherein the porous layer is formed by sputtering an alloy target.

10. The laminated film according to claim 1, wherein the porous layer is provided on both sides of the substrate.

11. The laminated film according to claim 1, wherein the surface of the substrate on the porous layer side contains a resin.

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