JP2010080437A - Electrolyte membrane-catalyst layer laminate with reinforcing sheet and polymer electrolyte fuel cell equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrolyte membrane-catalyst layer laminate capable of sufficiently restraining expansion and shrinkage of an electrolyte membrane and not causing damages on the electrolyte membrane even if a battery is operated for a long time and capable of restraining generation of gas leakage. <P>SOLUTION: The electrolyte membrane-catalyst layer laminate with a reinforcing sheet is an electrolyte membrane-catalyst layer laminate provided with a solid polymer electrolyte membrane and a catalyst layer, wherein (1) catalyst layers are laminated on either face of the solid polymer electrolyte membrane, (2) a reinforcing sheet of a frame shape having an opening part in a center at least on one face of the electrolyte membrane-catalyst layer laminate is installed so as to contact with an outer circumferential side face of the solid polymer electrolyte membrane, (3) the reinforcing sheet is composed of (i) a first adhesive layer and (ii) at least one sheet selected from a polyolephine sheet, a fabric sheet and a porous sheet, and (4) the first adhesive layer composing the reinforcing sheet adheres to an outer circumferential side face of the solid polymer electrolyte membrane. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrolyte membrane-catalyst layer laminate with a reinforcing sheet and a polymer electrolyte fuel cell comprising the same.

  A fuel cell is a cell in which electrodes are arranged on both sides of an electrolyte and generates electricity by an electrochemical reaction between hydrogen and oxygen, and only water is generated during power generation. Thus, unlike conventional internal combustion engines, fuel cells are expected to become popular as next-generation clean energy systems because they do not generate environmental load gases such as carbon dioxide. In particular, the polymer electrolyte fuel cell has a low operating temperature and low electrolyte resistance. In addition, it uses a highly active catalyst, so it can achieve high output even with a small size. Is expected to be put to practical use.

  This polymer electrolyte fuel cell uses a solid polymer electrolyte membrane having proton conductivity, and a catalyst layer and a gas diffusion layer are sequentially laminated on both surfaces of the electrolyte membrane. And it has the structure which has arrange | positioned the gasket so that the circumference | surroundings of the electrode which consists of this catalyst layer and a gas diffusion layer may be enclosed, and also this was pinched | interposed with the separator. Further, since the gasket is installed so as to surround the outer side of the electrode from the viewpoint of positional accuracy, a gap is formed between the gasket and the electrode, and the electrolyte membrane corresponding to this gap portion is an electrode. It is in a state where it is not pressed by either of the gaskets. Here, when power generation and non-power generation of the polymer electrolyte fuel cell are repeated, the electrolyte membrane repeats a wet state and a dry state, but the electrolyte membrane corresponding to the gap portion is pressed by an electrode or a gasket. Therefore, expansion and contraction are repeated (see Non-Patent Document 1). As a result, the electrolyte membrane is fatigued, and the electrolyte membrane is damaged when used for a long time.

  In order to solve this problem, for example, the polymer electrolyte fuel cell disclosed in Patent Document 1 further includes a reinforcing film in a gap between the electrode and the gasket. This reinforcing membrane is formed in a frame shape having an opening at the center as in the case of the gasket, and the outer peripheral edge of the reinforcing membrane is sandwiched between the gasket and the electrolyte membrane. The peripheral edge is sandwiched between the separator and the gas diffusion layer. As described above, the polymer electrolyte fuel cell of Patent Document 1 uses the reinforcing membrane to restrain the gap portion between the gasket and the electrode, thereby suppressing expansion and contraction of the electrolyte membrane. Yes.

  However, the reinforcing membrane of Patent Document 1 is a membrane composed of a single layer of fluororesin or the like, and a gasket is directly disposed on the membrane. By adopting such a configuration, However, it is impossible to sufficiently relax the expansion and contraction of the electrolyte membrane. Therefore, when the battery is operated for a long time, the electrolyte membrane may not be sufficiently damaged, and further improvement is desired.

  In Patent Document 2, the outer peripheral surface of the electrolyte membrane is sandwiched by at least a part of the outer peripheral surface via the first outer peripheral member and the second outer peripheral member, and the outer peripheral side surface of the electrolyte membrane is the first outer peripheral member and the second outer peripheral member. The surface of the first outer edge member and the second outer edge member on the electrolyte membrane side is not fixed by the outer edge member, and is easy to slide with respect to the electrolyte membrane. Since the electrolyte membrane can slide with respect to the sealing member even if the change occurs, the stress generated in the electrolyte membrane due to the dimensional change can be reduced, and therefore the breakage of the electrolyte membrane can be prevented.

  However, in Patent Document 2, the outer edge side surface of the electrolyte membrane is not fixed by the seal member, and expansion and contraction are not suppressed. Therefore, when the battery is operated for a long time, the electrolyte membrane may not be sufficiently damaged. Further, since there is a risk of gas leakage because it is not fixed, further improvement is desired.

Japanese Patent No. 3052536 JP 2008-34116 A

Application Brief TA No.76 2005. 6 SII Nanotechnology Inc.

  An object of the present invention is to provide an electrolyte membrane-catalyst layer laminate in which expansion and contraction of the electrolyte membrane are sufficiently suppressed so that the electrolyte membrane is not damaged even when the battery is operated for a long time, and the occurrence of gas leak can be suppressed. It is to be.

  As a result of intensive studies in view of the above problems, the present inventors have used an electrolyte membrane-catalyst layer laminate in which the above problems have been solved by using a reinforcing sheet using a specific layer structure and a specific material. It was found that can be obtained. The present invention has been completed based on such findings. That is, the present invention relates to the following electrolyte membrane-catalyst layer laminate with a reinforcing sheet.

Item 1. An electrolyte membrane-catalyst layer laminate comprising a solid polymer electrolyte membrane and a catalyst layer,
(1) A catalyst layer is laminated on each side of the solid polymer electrolyte membrane,
(2) A frame-shaped reinforcing sheet having an opening in the center is installed on at least one surface of the electrolyte membrane-catalyst layer laminate so as to be in contact with the outer peripheral side surface of the solid polymer electrolyte membrane,
(3) The reinforcing sheet is composed of (i) a first adhesive layer, and (ii) at least one sheet selected from a polyolefin sheet, a fibrous sheet, and a porous sheet,
(4) The first adhesive layer constituting the reinforcing sheet is fixed to the outer peripheral side surface of the solid polymer electrolyte membrane.
An electrolyte membrane-catalyst layer laminate with a reinforcing sheet.

  Item 2. Item 2. The electrolyte membrane-catalyst layer laminate according to Item 1, wherein the fibrous sheet of (ii) is a nonwoven fabric.

  Item 3. Item 3. The electrolyte membrane-catalyst layer stack according to Item 1 or 2, wherein the material of the fibrous sheet (ii) is (A) natural fiber, or (B) a fiber made of a synthetic resin having a melting point of 200 ° C or higher. body.

  Item 4. Item 2. The electrolyte membrane-catalyst layer laminate according to Item 1, wherein the polyolefin sheet of (ii) is polyethylene or polypropylene.

  Item 5. Item 5. The electrolyte membrane-catalyst layer laminate according to any one of Items 1 to 4, wherein a second adhesive layer is further formed on the side opposite to the first adhesive layer on the sheet of (ii).

  Item 6. Item 6. The electrolyte membrane-catalyst layer laminate according to Item 5, wherein a gasket is further disposed on the second adhesive layer.

  Item 7. Item 7. A polymer electrolyte fuel cell comprising the electrolyte membrane-catalyst layer laminate according to any one of Items 1 to 6.

1. Electrolyte membrane-catalyst layer laminate with reinforcing sheet The electrolyte membrane-catalyst layer laminate with reinforcing sheet of the present invention is an electrolyte membrane-catalyst layer laminate comprising a solid polymer electrolyte membrane and a catalyst layer,
(1) A catalyst layer is laminated on each side of the solid polymer electrolyte membrane,
(2) A frame-shaped reinforcing sheet having an opening in the center is installed on at least one surface of the electrolyte membrane-catalyst layer laminate so as to be in contact with the outer peripheral side surface of the solid polymer electrolyte membrane,
(3) The reinforcing sheet is composed of (i) a first adhesive layer, and (ii) at least one sheet selected from a polyolefin sheet, a fibrous sheet, and a porous sheet,
(4) The 1st contact bonding layer which comprises the said reinforcement sheet is adhering to the outer peripheral side surface of a solid polymer electrolyte membrane.

  Thus, by disposing a specific reinforcing sheet, it is possible to suppress damage to the electrolyte membrane-catalyst layer laminate, and to prevent gas leakage of fuel gas such as hydrogen.

  The electrolyte membrane-catalyst layer laminate used in the present invention, for example, as shown in FIG. 1, is a double-sided surface excluding the outer peripheral edge of a solid polymer electrolyte membrane (hereinafter also simply referred to as “electrolyte membrane”). The catalyst layer may be laminated on the (upper surface and lower surface) (first embodiment), or the catalyst layer and the electrolyte membrane may have the same shape and size as shown in FIG. A catalyst layer (second embodiment) in which a catalyst layer is laminated on the entire surface (upper surface and lower surface) may be used.

  Especially, it is preferable that the catalyst layer on at least one side of the electrolyte membrane is formed slightly smaller than the electrolyte membrane from the viewpoint that the first adhesive layer in the reinforcing sheet described below is easily fixed to the electrolyte membrane. . In this case, the catalyst layer is not formed on the outer peripheral edge of at least one surface of the electrolyte membrane. The distance A from the outer periphery of the electrolyte membrane to the outer periphery of the catalyst layer at this time is not particularly limited, but is preferably about 0 to 10 mm (particularly about 1 to 8 mm), for example.

  The electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention has a frame shape having an opening at the center on at least one surface of the electrolyte membrane-catalyst layer laminate so as to be in contact with the outer peripheral side surface of the solid polymer electrolyte membrane. Reinforcing sheet is installed. The reinforcing sheet includes (i) a first adhesive layer, and (ii) at least one sheet selected from a polyolefin sheet, a fibrous sheet, and a porous sheet (hereinafter also referred to as “reinforcing base sheet”). The first adhesive layer is fixed to the outer peripheral side surface of the electrolyte membrane.

When catalyst layers are stacked on both sides of the electrolyte membrane excluding the outer peripheral edge (FIG. 1)
For example, as shown in FIG. 3, the first adhesive layer may be disposed on the electrolyte membrane so as to cover the outer peripheral edge and side surfaces of the upper and lower surfaces of the electrolyte membrane, and may be fixed at each location. It is done. A reinforcing base sheet is laminated on each of the upper surface and the lower surface of the first adhesive layer. The reinforcing base sheet may be laminated on the entire surface of the first adhesive layer, or may be laminated only on a part thereof, but in the present invention, the first adhesive layer and the reinforcing base sheet are in plan view. It is preferable that they have substantially the same shape and size.

  This reinforcing sheet may be disposed on at least one surface of the electrolyte membrane-catalyst layer laminate so as to be in contact with the outer peripheral side surface of the electrolyte membrane and fixed to the outer peripheral side surface of the electrolyte membrane. For example, as shown in FIG. Moreover, you may arrange | position not only on the outer periphery part of an electrolyte membrane but on the outer periphery part of the catalyst layer currently formed on the electrolyte membrane.

  The distance B of the reinforcing sheet that protrudes from the electrolyte membrane is not particularly limited, but is preferably about 5 to 50 mm (particularly about 10 to 30 mm), for example. Further, the distance C of the reinforcing sheet laminated on the outer peripheral edge of the electrolyte membrane (and further on the outer peripheral edge of the catalyst layer) is not limited, but is, for example, about 1 to 30 mm (particularly about 3 to 20 mm). Preferably there is.

  A second adhesive layer may be further laminated on the outer side of the reinforcing sheet used in the present invention (that is, the surface of the reinforcing base sheet opposite to the first adhesive layer). A gasket may be disposed on the top (FIG. 5). Thereby, gas leak can be prevented more reliably. Also in this case, the reinforcing sheet and the gasket may be disposed not only on the outer peripheral edge portion of the electrolyte membrane but also on the outer peripheral edge portion of the catalyst layer formed on the electrolyte membrane ( FIG. 6).

  An electrolyte membrane-electrode assembly is obtained by disposing known or commercially available gas diffusion layers on the catalyst layers on both sides of the electrolyte membrane-catalyst layer laminate of the present invention obtained as described above. Moreover, a polymer electrolyte fuel cell can be manufactured by arrange | positioning a well-known or commercially available separator on both surfaces of the said electrolyte membrane electrode assembly.

When the catalyst layer is laminated on the entire surface (upper and lower surfaces) of the electrolyte membrane (Fig. 2)
In this case, as shown in FIG. 7, the first adhesive layer is disposed so as to cover the side surface of the electrolyte membrane, the side surface of the catalyst layer, and the outer peripheral edge, and is fixed at each location. A reinforcing base sheet is laminated on each of the upper surface and the lower surface of the first adhesive layer. The reinforcing base sheet may be laminated on the entire surface of the first adhesive layer, or may be laminated only on a part thereof, but in the present invention, the first adhesive layer and the reinforcing base sheet are in plan view. It is preferable that they have substantially the same shape and size.

  The distance B of the reinforcing sheet that protrudes from the electrolyte membrane is not particularly limited, but is preferably about 5 to 50 mm (particularly about 10 to 30 mm), for example. Moreover, although the distance C of the reinforcement sheet laminated | stacked on the outer periphery part of a catalyst layer is not limited, For example, it is preferable that it is about 1-30 mm (especially about 3-20 mm).

  A second adhesive layer may be further laminated on the outer side of the reinforcing sheet used in the present invention (that is, the surface of the reinforcing base sheet opposite to the first adhesive layer). A gasket may be disposed on the top (FIG. 8). Thereby, gas leak can be prevented more reliably.

  An electrolyte membrane-electrode assembly is obtained by disposing known or commercially available gas diffusion layers on the catalyst layers on both sides of the electrolyte membrane-catalyst layer laminate of the present invention obtained as described above. Moreover, a polymer electrolyte fuel cell can be manufactured by arrange | positioning a well-known or commercially available separator on both surfaces of the said electrolyte membrane electrode assembly.

  In the above description, only the case where the reinforcing sheets are disposed on both surfaces of the electrolyte membrane-catalyst layer stack has been described. However, the present invention is not limited to this, and only one side of the electrolyte membrane-catalyst layer stack (for example, Further, it can be formed by disposing a reinforcing sheet formed in a frame shape on the upper surface or the lower surface, and this also has an effect of improving the tearing of the electrolyte membrane. As an example of this, the embodiment in which the reinforcing sheet formed in a frame shape is disposed only on the upper surface of the electrolyte membrane-catalyst layer laminate is shown for each of the cases where the sizes of the electrolyte membrane and the catalyst layer are different from each other. And 10.

The cathode catalyst layer is easily attacked by radicals, and it is likely to swell and shrink due to the increase or decrease of the generated water during operation, and the catalyst layer and the electrolyte membrane are likely to peel off. Is desirable.

  Edge catalyst is formed on the anode side because the anode catalyst layer is low humidified and water moves to the cathode side together with protons, and the catalyst layer and membrane are easily peeled off due to the catalyst layer and membrane shrinking. If this happens, this can be prevented.

  When reinforcing sheets are installed on both the anode side and the cathode side, it is also preferable to bond edge seal materials having different configurations (size, shape, composition) on the anode side and the cathode side.

  It should be noted that the reinforcing sheet is installed on both sides in order to protect the anode catalyst layer and the cathode catalyst layer with a reinforcing sheet and to further improve the durability of the electrolyte membrane-catalyst layer laminate during long-time operation. preferable.

  In the present invention, the catalyst layer is laminated on both surfaces of the first and second aspects except for the outer peripheral edge of the electrolyte membrane, and the size of the opening of the catalyst layer on the upper and lower surfaces of the electrolyte membrane. And when the catalyst layer is laminated on the entire surface of the electrolyte membrane and the size of the opening of the catalyst layer is different, the distance A to the outer periphery of the catalyst layer within the range described above, The distance B of the reinforcing sheet protruding from the electrolyte membrane and the distance C of the reinforcing sheet laminated on the outer peripheral edge of the catalyst layer can be selected.

  Further, the size of the catalyst layer may be different between the upper surface and the lower surface of the electrolyte membrane. By changing the size of the catalyst layer, damage to the electrolyte membrane by the catalyst layer during transfer of the catalyst layer can be suppressed. The cathode catalyst layer is susceptible to radical attack, and swelling / shrinkage occurs due to increase / decrease of generated water during operation, and peeling of the catalyst layer and the electrolyte membrane is likely to occur. Therefore, an edge seal may be installed at a portion where the cathode catalyst layer is enlarged.

  On the other hand, the anode catalyst layer is easily dried by water moving to the cathode side together with protons under low humidification conditions, and the catalyst layer and the electrolyte membrane are likely to peel off due to contraction of the catalyst layer and the membrane. Therefore, an edge seal may be installed at a portion where the anode catalyst layer is enlarged.

  Next, the material of each component of the electrolyte membrane-catalyst layer laminate configured as described above will be described.

As the solid polymer electrolyte membrane , a known or commercially available polymer electrolyte membrane can be used. For example, a solution containing a hydrogen ion conductive polymer electrolyte is coated on a substrate and dried. Can also be manufactured. Examples of the hydrogen ion conductive polymer electrolyte include a perfluorosulfonic acid-based fluorine ion exchange resin, more specifically, a perfluorocarbon sulfonic acid-based one in which the C—H bond of the hydrocarbon ion-exchange membrane is substituted with fluorine. Examples include polymers (PFS polymers). By introducing a fluorine atom having high electronegativity, it is chemically very stable, the dissociation degree of the sulfonic acid group is high, and high ion conductivity can be realized. Specific examples of such a hydrogen ion conductive polymer electrolyte include “Nafion” (registered trademark) manufactured by DuPont, “Flemion” (registered trademark) manufactured by Asahi Glass Co., Ltd., and “Aciplex” manufactured by Asahi Kasei Corporation. ”(Registered trademark),“ Gore Select ”(registered trademark) manufactured by Gore, and the like.

  In addition, as a hydrocarbon-based electrolyte ion-conductive polymer electrolyte, sulfonated (polystyrene-block-poly (ethylene-random-butylene) -block-polystyrene) manufactured by Aldrich Co. can be used.

  An ion conductive polymer electrolyte membrane impregnated with a liquid substance can also be used. The ion conductive polymer electrolyte membrane impregnated with the liquid substance is not particularly limited, and any ion conductive polymer electrolyte membrane may be used as long as it is hydrogen ion conductive, and a known or commercially available one can be used. For example, a membrane obtained by impregnating a porous polymer substrate film with phosphoric acid can be used. Specific examples of the ion conductive electrolyte membrane impregnated with such a liquid substance include “Celtec P” manufactured by BASF.

  Any one of hydrocarbon-based and fluororesin-based polymer electrolyte membranes can be used for conducting hydroxyl ions. The anionic polymer electrolyte membrane used in the present invention is preferably a high-concentration alkali-resistant fluororesin-based polymer electrolyte membrane when a high-concentration alkaline aqueous solution is used, and a low-concentration or alkaline aqueous solution is not used. From the viewpoint of cost, hydrocarbons are preferable. These selections are optimized as appropriate by the system.

  Examples of the hydrocarbon-based anionic polymer electrolyte membrane that can be used in the present invention include Aciplex (registered trademark) A-201, 211, and 221 manufactured by Asahi Kasei Corporation, and Neoceptor (registered trademark) AM manufactured by Tokuyama Corporation. Examples of fluororesin-based anion exchange membranes such as -1, AHA include Tosflex (registered trademark) IE-SF34 manufactured by Tosoh Corporation.

  The concentration of the solid polymer electrolyte contained in the solid polymer electrolyte-containing solution is usually about 5 to 60% by weight, preferably about 20 to 40% by weight. The thickness of the electrolyte membrane is usually about 20 to 250 μm, preferably about 20 to 80 μm.

  In addition, it is known that the solid polymer electrolyte membrane changes in size and shape with the absorption and release of water and expands and contracts (see Non-Patent Document 1), and depending on the temperature and humidity at which the fuel cell is operated, The dimensions change by about 0 to 10%.

The catalyst layer catalyst layer is a known or commercially available platinum-containing catalyst layer (cathode catalyst and anode catalyst). Specifically, the catalyst layer contains (1) carbon particles supporting catalyst particles and (2) a hydrogen ion conductive polymer electrolyte. Examples of the catalyst particles include platinum, a platinum alloy, a platinum compound, and the like. Examples of the platinum alloy include an alloy of platinum and at least one metal selected from ruthenium, palladium, nickel, molybdenum, iridium, and iron. In general, the catalyst particles contained in the cathode catalyst layer are platinum, and the catalyst particles contained in the anode catalyst layer are an alloy of the metal and platinum. Moreover, as a hydrogen ion conductive polymer electrolyte, the same material as what is used for the electrolyte membrane mentioned above can be used.

Examples of the resin constituting the adhesive layer adhesive layer include an epoxy resin, an acrylic resin, a urethane resin, a silicone resin, and a solid polymer electrolyte ionomer resin.

  Since the solid polymer electrolyte membrane expands and contracts, it is preferable that the reinforcing sheet can follow the expansion and contraction, and a solid polymer electrolyte ionomer resin is particularly preferable.

  Examples of the solid polymer electrolyte ionomer include Nafion (registered trademark) ionomer solution (manufactured by DuPont), Aciplex (registered trademark) ionomer solution (manufactured by Asahi Kasei Corporation), and Flemion (registered trademark) ionomer solution (manufactured by Asahi Glass Co., Ltd.). Etc. can be used suitably.

  In addition, as a hydrocarbon ionomer, for example, an electrolyte obtained by aminating a chloromethylated product of a copolymer of aromatic polyether sulfonic acid and aromatic polythioether sulfonic acid, or as a fluorine-based ionomer, for example, a sulfonic acid group A polymer obtained by treating the terminal of the perfluorocarbon polymer with a diamine and quaternizing it, or a polymer such as a quaternized product of polychloromethylsulfylene, which is preferably solvent-soluble can also be used.

  These electrolytes are usually dispersed in a concentration of about 5 to 30% by weight in an organic solvent such as alcohol or ether, or a mixed solvent of an organic solvent and water.

  The first adhesive layer and the second adhesive layer are not particularly limited as long as the first adhesive layer and the second adhesive layer are made of the above-described resin, and the resin constituting the first adhesive layer and the resin constituting the second adhesive layer are the same. May be different.

Polyolefin sheet, fibrous sheet and porous sheet In the present invention, at least one sheet (reinforcing base sheet) selected from a polyolefin sheet, a fibrous sheet and a porous sheet is provided on the upper surface and the lower surface of the first adhesive layer. Are stacked. Thereby, flexibility can be given to the reinforcing sheet while maintaining rigidity.

  In the present invention, the reinforcing base sheets laminated on the upper surface and the lower surface of the first adhesive layer may be the same or different. For example, a fibrous sheet may be laminated on the upper surface, and a porous sheet may be laminated on the lower surface, or vice versa.

  Examples of the polyolefin constituting the polyolefin sheet include polyethylene, polypropylene, low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, polystyrene, and polymethylpentene. Polypropylene is preferred from the viewpoint of heat resistance and durability.

  The fibrous sheet may be composed of any one of organic fibers and inorganic fibers, for example.

  As the organic fiber, any of natural fiber and synthetic resin fiber can be used.

  Examples of natural fibers include cellulose, wool, silk, cotton, and hemp.

  As the synthetic resin constituting the synthetic resin fiber, for example, commercially available resins having a melting point of 200 ° C. or higher can be widely used. Specifically, polyester, polyamide, polyimide, polymethylpentene (230 to 240 ° C.), polyphenylene oxide (285-288 ° C.), synthetic resins such as polysulfone, polyether ether ketone (334 ° C.), polyphenylene sulfide (280 ° C.), and the like.

  In the present invention, polyester is particularly preferable, and wholly aromatic polyester is particularly preferable. As such a wholly aromatic polyester, for example, a copolymer of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid (“Vectran” manufactured by Kuraray Co., Ltd., “Veculus” manufactured by Kuraray Co., Ltd.) And a copolymer of p-hydroxybenzoic acid, terephthalic acid, and 4,4′-dihydroxybisphenyl (“Sumika Super” manufactured by Sumitomo Chemical Co., Ltd.).

  Examples of the inorganic fiber include glass fiber, carbon fiber, rock fiber and the like.

  The fibrous sheet may be a woven fabric or a non-woven fabric. The fibrous sheet may be an unstretched sheet or may be a porous sheet stretched in a uniaxial or biaxial direction.

  In the present invention, a nonwoven fabric is preferred, and among these, a nonwoven fabric made of synthetic resin fibers is preferred, and a nonwoven fabric made of wholly aromatic polyester fibers is particularly preferred. Thereby, rigidity, flexibility, etc. can be improved further.

  The nonwoven fabric may be obtained by either a wet method or a dry method, but is preferably a dry method from the viewpoint of cost, solvent resistance and the like, and a melt blown method is particularly preferable among the dry methods.

The basis weight of the fibrous sheet is not limited, but may be, for example, about 5 to 25 g / m ² . The density of the fibrous sheet is not limited and is preferably about 0.15 to 0.45 g / cm ³ . By setting it as this range, flexibility etc. improve further.

  Examples of the material constituting the porous sheet include the same materials as the synthetic resin constituting the synthetic resin fiber. The porosity of the porous sheet may be, for example, about 10 to 80% by volume, preferably about 25 to 70% by volume.

  The porous sheet may be, for example, a needle punch method; an emboss roll method; a hot melt punch method; a physical punch method using a knife, a cutter, a rotary die roll or the like; a laser beam processing; a corona discharge; Can be manufactured.

Reinforcing sheet The reinforcing sheet used in the present invention has, for example, a frame shape having an opening in a plan view in the center as shown in FIG. 11, and a reinforcing substrate on the upper and lower surfaces of the first adhesive layer. Sheets are laminated. The shape of the opening of the reinforcing sheet and the outer shape of the reinforcing sheet itself are not limited, and both may be rectangular as shown in FIG. 11 or may be circular.

  The thickness of the reinforcing sheet is not limited, but is usually about 20 to 150 μm, preferably about 30 to 100 μm.

  In the present invention, in the reinforcing sheet, when a fibrous sheet and / or a porous sheet is used as the reinforcing base sheet, the first adhesive layer preferably penetrates into the reinforcing base sheet. Thereby, the adhesiveness of a 1st contact bonding layer and a reinforcement base material sheet improves, and peeling of a reinforcement base material sheet can be prevented at the time of battery operation. The thickness of the invading adhesive layer is not limited, but is preferably about 1 to 5 μm.

  Moreover, when the 2nd contact bonding layer is formed, it is preferable that the said 2nd contact bonding layer also has penetrate | invaded inside the reinforcement sheet. The thickness of the invading adhesive layer is not limited, but is preferably about 1 to 5 μm.

  The reinforcing sheet of the present invention can be produced, for example, by coating a solid polymer electrolyte ionomer on the reinforcing base sheet using a die coat or the like.

  The reinforcing sheet used in the present invention is formed by laminating the above-mentioned reinforcing base sheet on the upper surface and / or the lower surface of the above-mentioned first adhesive layer. Therefore, since the reinforcing sheet used in the present invention has flexibility while maintaining rigidity, when it is installed in the electrolyte membrane-catalyst layer laminate, the dimensional change of the electrolyte membrane-catalyst layer laminate (the electrolyte during battery operation) Expansion and contraction of the membrane can be suppressed. That is, when the electrolyte membrane expands, a force to compress the electrolyte membrane does not expand, and when the electrolyte membrane contracts, a force acts to relieve the contracting force, so that the shape of the electrolyte membrane is made as constant as possible. Thus, expansion and contraction of the electrolyte membrane can be suppressed. As a result, breakage of the electrolyte membrane-catalyst layer stack can be suppressed, and gas leakage of fuel gas such as hydrogen can be prevented.

Gasket In the present invention, a gasket may be further disposed on the second adhesive layer of the reinforcing sheet as necessary.

  As the gasket, it is possible to use a gasket that has a strength sufficient to withstand hot pressing and has a gas barrier property that does not leak fuel and oxidant to the outside. For example, a polyethylene terephthalate sheet, a Teflon (registered trademark) sheet, a silicone rubber sheet, a nitrile rubber sheet, an ethylene propylene rubber sheet, an acrylic rubber sheet and the like can be exemplified.

  The thickness of the gasket is preferably adjusted within a range of about ± 20 μm of the sum of the thickness of the catalyst layer and the thickness of the gas diffusion layer.

2. Manufacturing method of electrolyte membrane-catalyst layer laminate with reinforcing sheet The electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention has, for example, (1) a catalyst layer formed on both sides of a solid polymer electrolyte membrane, 2) Manufactured by placing two frame-shaped reinforcing sheets with an opening in the center on the catalyst layer-forming electrolyte membrane so that the adhesive layers face each other and hot pressing. In this case, it is not always necessary to use two frame-shaped reinforcing sheets, and it is possible to manufacture using only one sheet.

(1) Formation of catalyst layer In forming the catalyst layer on both sides of the solid polymer electrolyte membrane, for example, a catalyst layer forming transfer sheet is arranged so that the catalyst layer faces the electrolyte membrane, and the back side of the transfer sheet Then, a heat press is applied to transfer the catalyst layer to the electrolyte membrane, and the transfer substrate of the transfer sheet is peeled off. At this time, in consideration of workability, it is preferable to simultaneously laminate the catalyst layers on both surfaces of the electrolyte membrane, but the catalyst layers may be formed on each side.

  The pressure level of the heating press is usually about 0.5 to 20 MPa, preferably about 1 to 10 MPa in order to avoid transfer failure.

  It is preferable to heat the pressing surface during the pressing operation. The heating temperature is usually 200 ° C. or lower, preferably 150 ° C. or lower, in order to avoid damage or deformation of the electrolyte membrane. Thus, an electrolyte membrane-catalyst layer laminated body is formed by forming a catalyst layer on both surfaces of an electrolyte membrane. When a catalyst layer that is slightly smaller than the electrolyte membrane is used, the outer peripheral edge of the electrolyte membrane is exposed.

  The transfer sheet for forming a catalyst layer is obtained by forming a transfer catalyst layer on a transfer substrate. The transfer sheet for forming a catalyst layer is formed, for example, by preparing a paste composition for forming a catalyst layer by mixing and dispersing the above-described carbon particles supporting the catalyst particles and a hydrogen ion conductive polymer electrolyte in a solvent. The catalyst layer-forming paste composition is produced by applying the catalyst layer-forming paste composition onto a transfer substrate via a release layer as necessary, so that the catalyst layer has a desired film thickness. When a catalyst layer that is slightly smaller than the electrolyte membrane is used, the catalyst layer forming paste composition may be applied to the transfer substrate so as to have a shape that is slightly smaller than the electrolyte membrane.

  When applying the paste composition for forming a catalyst layer, the method is not particularly limited. For example, knife coater, bar coater, blade coater, spray, dip coater, spin coater, roll coater, die coater, curtain General methods such as coater and screen printing can be applied.

  The solvent is not limited, and known or commercially available solvents can be widely used. In the present invention, in particular, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, ethylene glycol are used. Monovalent or polyhydric alcohols having about 1 to 4 carbon atoms such as propylene glycol are preferred. These solvents can be used alone or in combination of two or more.

  After applying the paste composition for forming a catalyst layer, the catalyst layer is formed on the transfer substrate by drying at a predetermined temperature and time. The drying temperature is usually about 40 to 100 ° C, preferably about 60 to 80 ° C. The drying time varies depending on the drying temperature and cannot be generally specified, but is usually about 5 minutes to 2 hours, preferably about 10 minutes to 1 hour.

  As a transfer substrate, for example, polyimide, polyethylene terephthalate, polyparabanic acid aramid, polyamide (nylon, etc.), polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyetherimide, polyarylate, polyethylene naphthalate, etc. Can be mentioned. In addition, ethylene tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), etc. It is also possible to use a heat-resistant fluororesin. In addition to the polymer film, the transfer substrate may be coated paper such as art paper, coated paper, and lightweight coated paper, or non-coated paper such as notebook paper and copy paper. In the present invention, an inexpensive and easily available polymer film is preferable, and polyethylene terephthalate or the like is more preferable. The thickness of the transfer substrate is usually about 6 to 100 μm, preferably about 10 to 30 μm, from the viewpoints of handleability and economy.

(2) Attaching the reinforcing sheet Next, for example, two frame-shaped reinforcing sheets provided with openings on the electrolyte membrane-catalyst layer laminate, the catalyst layer-forming electrolyte membrane so that the first adhesive layer faces. Place the reinforcing sheet by placing and heat pressing.

  More specifically, for example, when the catalyst layers are laminated on both surfaces excluding the outer peripheral edge of the electrolyte membrane (FIG. 1), openings are provided on the upper and lower surfaces of the electrolyte membrane-catalyst layer laminate. A frame-shaped reinforcing sheet is arranged. At this time, the reinforcing sheets are arranged so that the first adhesive layers of the reinforcing sheets face each other. Next, the reinforcing sheets are respectively disposed on the outer peripheral edge of the electrolyte membrane so that the catalyst layer is exposed from the opening of the reinforcing sheet except for the outer peripheral edge, and then heated and pressed. At this time, the reinforcing sheet may be disposed not only on the outer peripheral edge of the electrolyte membrane but also on the outer peripheral edge of the catalyst layer.

  At this time, by performing the heat press, the adhesive layers of the two reinforcing sheets are heat-sealed to substantially form one first adhesive layer.

  When attaching the reinforcing sheet, as described above, only one frame-like reinforcing sheet provided with an opening may be used, and the reinforcing sheet may be attached only to one surface of the electrolyte membrane-catalyst layer laminate. . In this case, only one frame-like reinforcing sheet is used, and it can be attached in the same manner as above except that it is installed on the upper surface or the lower surface of the electrolyte membrane-catalyst layer laminate.

  The heating temperature is not limited as long as it is performed at a temperature at which the adhesive layer melts, but is usually 60 to 160 ° C, preferably about 80 to 130 ° C. The pressure level is usually about 0.05 to 5 MPa, preferably about 0.1 to 1 MPa.

  In addition, you may provide a gasket on a reinforcement sheet as needed. When this gasket is provided, the reinforcing sheet is a reinforcing sheet in which a first adhesive layer is laminated on one side of the reinforcing base sheet and a second adhesive layer is provided on the other side (first adhesive layer / reinforcing base sheet). / Laminate of the second adhesive layer), and the gasket may be hot-pressed on the second adhesive layer. The conditions for the hot press may be the same as those for providing the first adhesive layer.

  By providing a known or commercially available gas diffusion layer on both sides of the electrolyte membrane-catalyst layer laminate of the present invention, an electrolyte membrane-electrode assembly (MEA) can be obtained, and further known for the electrolyte membrane-electrode assembly. Alternatively, a polymer electrolyte fuel cell can be obtained by providing a commercially available separator.

  According to the electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention, damage to the electrolyte membrane-catalyst layer laminate can be sufficiently suppressed. Therefore, even when the battery is operated for a long time, a gas leak of fuel gas such as hydrogen can be prevented, and the durability time of the fuel cell can be improved.

FIG. 1 shows an example of a perspective view (a) and a cross-sectional view (b) of an electrolyte membrane-catalyst layer stack obtained using an electrolyte membrane and a catalyst layer that is slightly smaller than the electrolyte membrane. FIG. 2 shows an example of a perspective view (a) and a cross-sectional view (b) of an electrolyte membrane-catalyst layer laminate obtained by using an electrolyte membrane and a catalyst layer having the same shape and size. FIG. 3 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained using an electrolyte membrane-catalyst layer laminate having a catalyst layer that is slightly smaller than the electrolyte membrane. FIG. 4 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained using an electrolyte membrane-catalyst layer laminate having a catalyst layer that is slightly smaller than the electrolyte membrane. FIG. 5 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained using an electrolyte membrane-catalyst layer laminate having a catalyst layer that is slightly smaller than the electrolyte membrane. FIG. 6 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained by using an electrolyte membrane-catalyst layer laminate having a catalyst layer that is slightly smaller than the electrolyte membrane. FIG. 7 shows an example of a cross-sectional view of the electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained using an electrolyte membrane-catalyst layer laminate having the same shape and size of the catalyst layer and the electrolyte membrane. FIG. 8 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained using an electrolyte membrane-catalyst layer laminate having the same shape and size of the catalyst layer and the electrolyte membrane. FIG. 9 was obtained by using an electrolyte membrane-catalyst layer laminate in which the catalyst layer is slightly smaller than the electrolyte membrane, and installing a reinforcing sheet formed in a frame shape only on the upper surface of the electrolyte membrane-catalyst layer laminate. An example of sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet of this invention is shown. FIG. 10 shows that an electrolyte membrane-catalyst layer laminate having the same shape and size of the catalyst layer and the electrolyte membrane is used, and a reinforcing sheet formed in a frame shape is installed only on the upper surface of the electrolyte membrane-catalyst layer laminate. An example of sectional drawing of an electrolyte membrane-catalyst layer layered product with a reinforcing sheet of the present invention obtained by the present invention is shown. FIG. 11 shows an example of a plan view of a reinforcing sheet used in the present invention. FIG. 12 shows an example in which a catalyst layer having a catalyst layer slightly smaller than the electrolyte membrane is used as in Examples 13 and 15, and a reinforcing sheet having a different shape on the upper and lower surfaces of the electrolyte membrane-catalyst layer laminate. 1 shows an example of a cross-sectional view of an electrolyte membrane-catalyst layer laminate with a reinforcing sheet of the present invention obtained by installing. FIG. 13 shows an electrolyte membrane-catalyst layer laminate having the same shape and size of the catalyst layer and the electrolyte membrane as in Examples 14 and 16, and is formed on the upper and lower surfaces of the electrolyte membrane-catalyst layer laminate. An example of sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet | seat of this invention obtained by installing the reinforcement sheet | seat from which this differs is shown.

  The present invention will be described more specifically with reference to the following examples and comparative examples. The present invention is not limited to the following examples.

Example 1
As the electrolyte membrane, a Nafion membrane NRE212CS (manufactured by DuPont) having a thickness of 50 μm cut into a size of 75 mm × 75 mm was used.

Next, a transfer sheet for forming a catalyst layer was prepared as follows. First, 2 g of platinum catalyst-supported carbon (platinum supported amount: 45.7 wt%, manufactured by Tanaka Kikinzoku Kogyo Co., Ltd., “TEC10E50E”), 1-butanol 10 g, 3-butanol 10 g, fluororesin (5 wt% Nafion binder, DuPont) 20 g and 6 g of water were added, and these were stirred and mixed in a disperser to prepare a paste composition for forming a catalyst layer. Next, the prepared paste composition was applied to a polyester film (“X44”, manufactured by Toray Industries, Inc., thickness 25 μm) so that the platinum weight after drying the catalyst layer was 0.4 mg / cm ² and dried. Thus, a transfer sheet for forming a catalyst layer was produced.

  The transfer sheet for forming a catalyst layer produced as described above was cut into a size of 60 mm × 60 mm, and placed on each side of the electrolyte membrane so that the catalyst layer faced the electrolyte membrane side. And it heat-pressed on conditions of 135 degreeC, 5.0 Mpa, and 150 second, the catalyst layer was formed on both surfaces of the electrolyte membrane, and the electrolyte membrane-catalyst layer laminated body was produced. The catalyst layer had a thickness of 20 μm.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a die coating method using a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as an adhesive layer on one surface of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). The coated adhesive layer was dried so that the weight of the adhesive layer was 3 g / m ² and dried to obtain a reinforcing sheet of Example 1.

  This reinforcing sheet was cut into a size of 110 mm × 110 mm, and an opening having a size of 50 mm × 50 mm was formed at the center. Then, two reinforcing sheets are placed centered on both surfaces of the electrolyte membrane-catalyst layer laminate so that each adhesive layer faces the electrolyte membrane-catalyst layer laminate, and 100 ° C., 1.0 MPa, 30 seconds. The first adhesive layer of the reinforcing sheet was heat-sealed to the electrolyte membrane-catalyst layer laminate by hot pressing under the conditions described above to prepare an electrolyte membrane-catalyst layer laminate with a reinforcing sheet.

Example 2
As the electrolyte membrane, an Aciplex membrane (SF-702X, thickness 50 μm, manufactured by Asahi Kasei Co., Ltd.) having a thickness of 50 μm cut to a size of 75 mm × 75 mm was used.

Next, a transfer sheet for forming a catalyst layer was prepared as follows. First, 2 g of platinum catalyst supported carbon (platinum supported amount: 45.7 wt%, manufactured by Tanaka Kikinzoku Kogyo Co., Ltd., “TEC10E50E”), 10 g of 1-butanol, 10 g of 3-butanol, fluororesin (5 wt% Aciplex ionomer, Asahi Kasei Co., Ltd. (20 g) and water 6 g were added, and these were stirred and mixed with a disperser to prepare a paste composition for forming a catalyst layer. Next, the prepared paste composition was applied to a polyester film (“X44”, manufactured by Toray Industries, Inc., thickness 25 μm) so that the platinum weight after drying the catalyst layer was 0.4 mg / cm ² and dried. Thus, a transfer sheet for forming a catalyst layer was produced.

  The transfer sheet for forming a catalyst layer produced as described above was cut into a size of 60 mm × 60 mm, and placed on each side of the electrolyte membrane so that the catalyst layer faced the electrolyte membrane side. And it heat-pressed on conditions of 135 degreeC, 5.0 Mpa, and 150 second, the catalyst layer was formed on both surfaces of the electrolyte membrane, and the electrolyte membrane-catalyst layer laminated body was produced. The catalyst layer had a thickness of 20 μm.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a die coat method using 5 wt% Aciplex Ionomer (Asahi Kasei Co., Ltd.) as an adhesive layer on one side of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). Coating was performed so that the weight of the adhesive layer after drying was 3 g / m ² and drying was performed to obtain a reinforcing sheet of Example 2.

  This reinforcing sheet was cut into a size of 110 mm × 110 mm, and an opening having a size of 50 mm × 50 mm was formed at the center. Then, two reinforcing sheets are placed centered on both surfaces of the electrolyte membrane-catalyst layer laminate so that each adhesive layer faces the electrolyte membrane-catalyst layer laminate, and 100 ° C., 1.0 MPa, 30 seconds. The first adhesive layer of the reinforcing sheet was heat-sealed to the electrolyte membrane-catalyst layer laminate by hot pressing under the conditions described above to prepare an electrolyte membrane-catalyst layer laminate with a reinforcing sheet.

Example 3
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a die coating method using a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as an adhesive layer on one surface of a polyethylene film (LIX-0, thickness 60 μm, manufactured by Toyobo Co., Ltd., “Rix”). The coated adhesive layer was dried so that the weight of the adhesive layer was 3 g / m ² and dried to obtain a reinforcing sheet of Example 3.

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced using the reinforcing sheet of Example 3 in the same manner as in Example 1.

Example 4
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a non-woven fabric made of wholly aromatic polyester fibers (weighing 14 g / cm ² , thickness 50 μm, density 0.21 g / cm ³ , manufactured by Kuraray Co., Ltd.)
As a bonding layer on one side of “Veculus MBBK14F”), a 5 wt% Nafion solution (“
DE520 ”(manufactured by DuPont) was applied by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² and dried to obtain a reinforcing sheet of Example 4.

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced using the reinforcing sheet of Example 4 in the same manner as in Example 1.

Example 5
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is an adhesive layer on one side of an acrylic fiber (manufactured by Nippon Exlan Industry Co., Ltd., “Pre-Reel”), and a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) is dried by a die coating method. Coating was performed so that the weight was 3 g / m ² and drying was performed to obtain a reinforcing sheet of Example 5.

  Next, using the reinforcing sheet of Example 5, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1.

Example 6
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is an epoxy resin adhesive (“EXA-4710”, manufactured by DIC Corporation) as an adhesive layer on one surface of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). ) Was applied by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² and dried to obtain a reinforcing sheet of Example 6.

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1 using the reinforcing sheet of Example 6.

Example 7
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is an acrylic resin adhesive (“Acridic”, manufactured by DIC Corporation) as an adhesive layer on one side of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). Was coated by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² and dried to obtain a reinforcing sheet of Example 7.

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced using the reinforcing sheet of Example 7 in the same manner as in Example 1.

Example 8
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”) with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a first adhesive layer. After coating with a die coating method so that the weight of the adhesive layer after drying is 3 g / m ² , a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) is die coated on the other surface as a second adhesive layer. The coating was applied so that the weight of the adhesive layer after drying by the method was 3 g / m ² and dried to obtain a reinforcing sheet (first adhesive layer / reinforced base sheet / second adhesive layer).

  Next, by placing a gasket made of ethylene propylene rubber (“EPDM”, thickness 200 μm) made of ethylene propylene rubber on the second adhesive layer, the reinforcing sheet of Example 8 (first adhesive layer / Reinforced base sheet / second adhesive layer / gasket) was obtained.

  An electrolyte membrane-catalyst layer laminate (with gasket) with a reinforcing sheet was produced in the same manner as in Example 1, except that two reinforcing sheets of Example 8 were used.

Example 9
An electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 2 using the same material as in Example 2.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is die coated with 5 wt% Aciplex Ionomer (Asahi Kasei Co., Ltd.) as a first adhesive layer on one side of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). After applying the coating method so that the weight of the adhesive layer after drying is 3 g / m ² , 5 wt% Aciplex Ionomer (manufactured by Asahi Kasei Co., Ltd.) is applied to the other surface as a second adhesive layer by a die coating method. Coating was performed so that the weight of the adhesive layer after drying was 3 g / m ² and drying was performed to obtain a reinforcing sheet (first adhesive layer / reinforcing base sheet / second adhesive layer).

  Next, by placing a gasket made of ethylene propylene rubber (“EPDM”, thickness 200 μm) made of ethylene propylene rubber on the second adhesive layer, the reinforcing sheet of Example 9 (first adhesive layer / Reinforced base sheet / second adhesive layer / gasket) was obtained.

  An electrolyte membrane-catalyst layer laminate (with gasket) with a reinforcing sheet was produced in the same manner as in Example 2, except that two reinforcing sheets of Example 9 were used.

Example 10
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a polyethylene film (LIX-0, thickness 60 μm, manufactured by Toyobo Co., Ltd., “Rix”) with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a first adhesive layer. After coating with a die coating method so that the weight of the adhesive layer after drying is 3 g / m ² , a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) is die coated on the other surface as a second adhesive layer. The adhesive sheet after drying by the method is applied so that the weight is 3 g / m ² and dried to obtain a reinforcing sheet of Example 10 (first adhesive layer / reinforced base sheet / second adhesive layer). It was.

  An electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1 except that two reinforcing sheets of Example 10 were used.

Example 11
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a first adhesive layer on one surface of a nonwoven fabric made of wholly aromatic polyester fibers (weighing 14 g / cm ² , thickness 50 μm, density 0.21 g / cm ³ , manufactured by Kuraray Co., Ltd., “Veculus MBBK14F”). As a second adhesive layer on the other surface, a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) was applied by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ^2. A 5 wt% Nafion solution (“DE520”, manufactured by DuPont) was applied by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² , dried, and the reinforcing sheet of Example 11 (No. 1) 1 adhesive layer / reinforced base sheet / second adhesive layer) was obtained.

  An electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1 except that two reinforcing sheets of Example 11 were used.

Example 12
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. Reinforcement sheet is bonded after drying by die coating with 5wt% Nafion solution ("DE520", manufactured by DuPont) as a first adhesive layer on one side of acrylic fiber (Nippon Exlan Kogyo Co., Ltd., "Pre-Reel") After coating so that the weight of the layer is 3 g / m ² , the adhesive layer after drying the other surface with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a second adhesive layer by the die coating method The coating was applied so that the weight was 3 g / m ² and dried to obtain a reinforcing sheet of Example 12 (first adhesive layer / reinforcing substrate sheet / second adhesive layer).

  Next, using the two reinforcing sheets of Example 12, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1.

Example 13
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is an epoxy resin adhesive (“EXA-4710”, DIC Corporation) as a first adhesive layer on one side of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). )) Was applied by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ^2, and then the epoxy resin adhesive (“EXA-4710”, DIC Co., Ltd.) was coated by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² , dried, and then reinforced sheet (first adhesive layer / reinforced substrate sheet / second adhesive). Layer).

  Next, by placing a gasket made of ethylene propylene rubber (“EPDM”, thickness 200 μm) made of ethylene propylene rubber on the second adhesive layer, the reinforcing sheet of Example 8 (first adhesive layer / Reinforced base sheet / second adhesive layer / gasket) was obtained.

  An electrolyte membrane-catalyst layer laminate (with gasket) with a reinforcing sheet was produced in the same manner as in Example 1 except that two reinforcing sheets of Example 13 were used.

Example 14
An electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 2 using the same material as in Example 2.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is an acrylic resin adhesive (“Acridic”, DIC Corporation) as a first adhesive layer on one side of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). Manufactured by coating with a die coating method so that the weight of the adhesive layer after drying is 3 g / m ^2, and the other side is also coated with an acrylic resin adhesive (“Acridic”, DIC ( Co., Ltd.) was coated by a die coating method so that the weight of the adhesive layer after drying was 3 g / m ² and dried to obtain a reinforcing sheet (first adhesive layer / reinforced base sheet / second adhesive layer). Got.

  Next, an ethylene propylene rubber gasket (manufactured by NOK Co., Ltd., “EPDM”, thickness of 200 μm) is disposed on the second adhesive layer, whereby the reinforcing sheet of Example 14 (first adhesive layer / Reinforced base sheet / second adhesive layer / gasket) was obtained.

  An electrolyte membrane-catalyst layer laminate (with gasket) with a reinforcing sheet was produced in the same manner as in Example 2 except that two reinforcing sheets of Example 14 were used.

Example 15
An electrolyte membrane having the same dimensions as the electrolyte membrane and the catalyst layer by using the same material as in Example 1 and using the same method as in Example 1 to make the electrolyte membrane 60 × 60 mm and the catalyst layer 60 × 60 mm. A catalyst layer laminate was prepared.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a die coating method using a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as an adhesive layer on one surface of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). The coated adhesive layer was dried so that the weight of the adhesive layer was 3 g / m ² and dried to obtain a reinforcing sheet of Example 15.

  This reinforcing sheet was cut into a size of 110 mm × 110 mm, and an opening having a size of 50 mm × 50 mm was formed at the center. Then, two reinforcing sheets are placed centered on both surfaces of the electrolyte membrane-catalyst layer laminate so that each adhesive layer faces the electrolyte membrane-catalyst layer laminate, and 100 ° C., 1.0 MPa, 30 seconds. The first adhesive layer of the reinforcing sheet was heat-sealed to the electrolyte membrane-catalyst layer laminate by hot pressing under the conditions described above to prepare an electrolyte membrane-catalyst layer laminate with a reinforcing sheet.

Example 16
An electrolyte membrane having the same dimensions as the electrolyte membrane and the catalyst layer by using the same material as in Example 1 and using the same method as in Example 1 to make the electrolyte membrane 60 × 60 mm and the catalyst layer 60 × 60 mm. A catalyst layer laminate was prepared.

Subsequently, a reinforcing sheet was produced. Reinforcement sheet is bonded after drying by die coating with 5wt% Nafion solution ("DE520", manufactured by DuPont) as a first adhesive layer on one side of acrylic fiber (Nippon Exlan Kogyo Co., Ltd., "Pre-Reel") After coating so that the weight of the layer is 3 g / m ² , the adhesive layer after drying the other surface with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a second adhesive layer by the die coating method The weight of the coating was applied to be 3 g / m ² and dried to obtain a reinforcing sheet of Example 16 (first adhesive layer / reinforced base sheet / second adhesive layer).

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1 using the reinforcing sheet of Example 16.

Example 17
An electrolyte membrane-catalyst layer laminate was prepared using the same material as in Example 1 and the same method as in Example 1, with the electrolyte membrane being 75 mm × 75 mm and the catalyst layer being 60 × 60 mm.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”) with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a first adhesive layer. The reinforcing sheet of Example 17 was obtained by coating with a die coating method such that the weight of the adhesive layer after drying was 3 g / m ² and drying.

  The two reinforcing sheets were cut into a size of 110 mm × 110 mm, and an opening with a size of 50 mm × 50 mm and an opening with a size of 52 × 52 mm were formed in the center of each reinforcing sheet.

  Then, two types of reinforcing sheets having different openings are arranged centering on both surfaces of the electrolyte membrane-catalyst layer laminate so that each first adhesive layer faces the electrolyte membrane-catalyst layer laminate. Electrolytic membrane-catalyst layer with reinforcing sheet of Example 13 by thermally fusing the first adhesive layer of the reinforcing sheet to the electrolyte membrane-catalyst layer laminate by hot pressing at 1.0 MPa for 30 seconds A laminate was produced. In addition, sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcing sheet of Example 17 is as FIG. 12 shows.

Example 18
An electrolyte membrane-catalyst layer laminate was produced by using the same material as in Example 1 and using the same method as in Example 1 to make the electrolyte membrane 60 mm × 60 mm and the catalyst layer 60 × 60 mm.

Subsequently, a reinforcing sheet was produced. The reinforcing sheet is a die coating method using a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as an adhesive layer on one surface of a polypropylene film (P2732, thickness 20 μm, manufactured by Toyobo Co., Ltd., “Pyrene-OT”). The coated adhesive layer was dried so that the weight of the adhesive layer was 3 g / m ² and dried to obtain a reinforcing sheet of Example 18.

  The two reinforcing sheets were cut into a size of 110 mm × 110 mm, and openings of 50 mm × 50 mm and 52 × 52 mm were formed in the center of each reinforcing sheet. Then, two types of reinforcing sheets having different openings are arranged centering on both surfaces of the electrolyte membrane-catalyst layer laminate so that each adhesive layer faces the electrolyte membrane-catalyst layer laminate. Electrolytic membrane-catalyst layer laminate with reinforcing sheet of Example 18 by thermally pressing the first adhesive layer of the reinforcing sheet to the electrolyte membrane-catalyst layer laminate by hot pressing at 0.0 MPa for 30 seconds Was made. In addition, sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet of Example 18 is as FIG. 13 shows.

Example 19
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1, with the electrolyte membrane being 75 mm × 75 mm and the catalyst layer being 60 × 60 mm.

Subsequently, a reinforcing sheet was produced. Reinforcement sheet is bonded after drying by die coating with 5wt% Nafion solution ("DE520", manufactured by DuPont) as a first adhesive layer on one side of acrylic fiber (Nippon Exlan Kogyo Co., Ltd., "Pre-Reel") After coating so that the weight of the layer is 3 g / m ² , the adhesive layer after drying the other surface with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a second adhesive layer by the die coating method The weight of the coating was applied to be 3 g / m ² and dried to obtain a reinforcing sheet of Example 19 (first adhesive layer / reinforcing base sheet / second adhesive layer). The two reinforcing sheets were cut into a size of 110 mm × 110 mm, and openings of 50 mm × 50 mm and 52 × 52 mm were formed in the center of each reinforcing sheet.

  Next, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1 using the reinforcing sheet of Example 19. In addition, sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet of Example 19 is as FIG. 12 shows.

Example 20
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1, with the electrolyte membrane being 60 mm × 60 mm and the catalyst layer being 60 × 60 mm.

Subsequently, a reinforcing sheet was produced. Reinforcement sheet is bonded after drying by die coating with 5wt% Nafion solution ("DE520", manufactured by DuPont) as a first adhesive layer on one side of acrylic fiber (Nippon Exlan Kogyo Co., Ltd., "Pre-Reel") After coating so that the weight of the layer is 3 g / m ² , the adhesive layer after drying the other surface with a 5 wt% Nafion solution (“DE520”, manufactured by DuPont) as a second adhesive layer by the die coating method The weight of the coating was applied to be 3 g / m ² and dried to obtain a reinforcing sheet (first adhesive layer / reinforcing base sheet / second adhesive layer) of Example 20. The two reinforcing sheets were cut into a size of 110 mm × 110 mm, and openings of 50 mm × 50 mm and 52 × 52 mm were formed in the center of each reinforcing sheet.

  Next, using the reinforcing sheet of Example 20, an electrolyte membrane-catalyst layer laminate with a reinforcing sheet was produced in the same manner as in Example 1. In addition, sectional drawing of the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet of Example 20 is as FIG. 13 shows.

Comparative Example 1
An electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1 using the same material as in Example 1 without using the reinforcing sheet.

Comparative Example 2
An electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 2 using the same material as in Example 2 without using the reinforcing sheet.

Comparative Example 3
Using the same material as in Example 1, an electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 1.

  Subsequently, a reinforcing sheet was produced. A 100 mm square polypropylene sheet (Toray Industries, Inc., “Trephan BO”, thickness 40 μm) was used, and then an opening having a size of 50 mm × 50 mm was formed at the center. An electrolyte membrane-catalyst layer laminate with a reinforcing sheet of Comparative Example 3 was produced in the same manner as in Example 1 except that a total of 2 sheets of this polypropylene sheet were used as reinforcing sheets.

Comparative Example 4
An electrolyte membrane-catalyst layer laminate was produced in the same manner as in Example 2 using the same material as in Example 2.

  Subsequently, a reinforcing sheet was produced. A 100 mm square polypropylene sheet (Toray Industries, Inc., “Trephan BO”, thickness 40 μm) was used, and then an opening having a size of 50 mm × 50 mm was formed at the center. An electrolyte membrane-catalyst layer laminate with a reinforcing sheet of Comparative Example 4 was produced in the same manner as in Example 2 except that a total of 2 sheets of this polypropylene sheet were used as reinforcing sheets.

  The materials used in each example and comparative example are as shown in Tables 1 and 2.

(Evaluation method 1)
Regarding the electrolyte membrane-catalyst layer laminates with reinforcing sheets of Examples 1 to 20 and Comparative Examples 1 to 4, electrolyte membrane-electrode bonding was performed by laminating a gas diffusion layer (carbon paper) on each catalyst layer surface by hot pressing. A body (MEA) was produced, and a separator was installed on the MEA to produce a polymer electrolyte fuel cell, and a load fluctuation cycle test was conducted. The measurement conditions at this time were a cell temperature of 80 ° C., a fuel utilization rate of 70%, an oxidant utilization rate of 40%, and a humidification temperature of 50 ° C. The load fluctuation condition was performed by scanning 0.01 A / cm ² and 0.3 A / cm ² at intervals of 1 minute. The evaluation was performed based on the continuous operation possible time, the amount of gas leakage, and whether or not the electrolyte membrane was broken.

  The results of the current voltage measurement evaluation are shown in Table 3.

  As a result of the current voltage measurement evaluation, the continuous operation possible time of the fuel cells of Examples 1 to 20 is 960 to 1000 hours, and the durability time of the fuel cells of Comparative Examples 1 to 4 is 250 to 500 hours, It turned out that the cell of an Example is excellent in durability.

Moreover, as a result of electrically measuring the amount of hydrogen gas leak, the fuel cells of Examples 1 to 20 were 1.2 to 2.3 mA / cm ² , which was not much different from the initial performance, but those of Comparative Examples 1 to 4 In the fuel cell, it is 15.2 to 16.3 mA / cm ² , which is considered to be caused by hydrogen leakage due to deterioration of the electrolyte membrane.

  Furthermore, when the fuel cell was disassembled after the evaluation, no breakage of the electrolyte membrane was observed in Examples 1 to 20. On the other hand, in Comparative Examples 1 to 4, the electrolyte membrane was visually damaged.

  In particular, in Comparative Examples 3 and 4, a sufficient improvement effect was not obtained even though a reinforcing sheet made of polypropylene was provided. This is considered to be because the reinforcing sheet is not fixed to the electrolyte membrane.

(Evaluation method 2)
About the electrolyte membrane-catalyst layer laminated body with a reinforcement sheet | seat of Examples 1-20 and Comparative Examples 1-4, the storage test in a constant temperature / humidity tank is performed, About a dimensional change in each temperature and humidity, using a metal ruler Dimensional measurement was performed visually, and the dimensional change rate before and after the storage test was expressed. A positive value indicates expansion, and a negative value indicates contraction.

(Dimensional change rate) = (Dimension after evaluation−Dimension before evaluation) / (Dimension before evaluation) × 100 (%
)

  Table 4 shows the results of the storage test.

  Thus, in the polymer electrolyte fuel cells of Examples 1 to 20, the increase in the durability time was observed and the dimensional change rate was suppressed. Therefore, the electrolyte membrane-catalyst layer lamination with a reinforcing sheet of the present invention was performed. It can be seen that the problem of electrolyte membrane breakage was solved by using the body.

DESCRIPTION OF SYMBOLS 1 Electrolyte membrane 2 Catalyst layer 3 1st contact bonding layer 4 Reinforcement base material sheet 5 Reinforcement sheet 6 2nd contact bonding layer 7 Gasket 8 Opening part

Claims (7)

An electrolyte membrane-catalyst layer laminate comprising a solid polymer electrolyte membrane and a catalyst layer,
(1) A catalyst layer is laminated on each side of the solid polymer electrolyte membrane,
(2) A frame-shaped reinforcing sheet having an opening in the center is installed on at least one surface of the electrolyte membrane-catalyst layer laminate so as to be in contact with the outer peripheral side surface of the solid polymer electrolyte membrane,
(3) The reinforcing sheet is composed of (i) a first adhesive layer, and (ii) at least one sheet selected from a polyolefin sheet, a fibrous sheet, and a porous sheet,
(4) The first adhesive layer constituting the reinforcing sheet is fixed to the outer peripheral side surface of the solid polymer electrolyte membrane.
An electrolyte membrane-catalyst layer laminate with a reinforcing sheet. The electrolyte membrane-catalyst layer laminate according to claim 1, wherein the fibrous sheet of (ii) is a nonwoven fabric. The electrolyte membrane-catalyst layer according to claim 1 or 2, wherein the material of the fibrous sheet (ii) is (A) natural fiber or (B) a fiber made of a synthetic resin having a melting point of 200 ° C or higher. Laminated body. The electrolyte membrane-catalyst layer laminate according to claim 1, wherein the polyolefin sheet of (ii) is polyethylene or polypropylene. The electrolyte membrane-catalyst layer laminate according to any one of claims 1 to 4, wherein a second adhesive layer is further formed on the side opposite to the first adhesive layer on the sheet of (ii). The electrolyte membrane-catalyst layer laminate according to claim 5, wherein a gasket is further disposed on the second adhesive layer. A polymer electrolyte fuel cell comprising the electrolyte membrane-catalyst layer laminate according to claim 1.

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