JP2019185923A - Manufacturing method for film electrode gas diffusion layer joined body - Google Patents

Abstract

To provide a manufacturing method for a film electrode gas diffusion layer joined body that makes it possible to reduce air bubbles generated between an adhesive and a resin sheet and a gas diffusion layer.SOLUTION: A manufacturing method for a film electrode gas diffusion layer joined body 10 for manufacturing a film electrode gas diffusion layer joined body 10 by disposing a gas diffusion layer 12 and a resin sheet 13 on a film electrode joined body 11, comprises: a step of applying an adhesive B on the film electrode joined body 11; and a step of placing a resin sheet 13 and a gas diffusion layer 12 on the adhesive B. In the step of applying the adhesive B onto the film electrode joined body 11, a screen mask comprising a frame-shaped first mask 21 and a rectangular second mask 22 coupled to inside of the first mask 21 via a mesh 23, and thinner than the first mask 21 is disposed on the film electrode joined body 11, and the first mask 21 and the second mask 22 are brought into contact with the film electrode joined body 11 and the adhesive B is applied while the mesh 23 is kept inclined to the film electrode joined body 11.SELECTED DRAWING: Figure 2C

Description

  The present invention relates to a method for producing a membrane electrode gas diffusion layer assembly.

  The membrane electrode gas diffusion layer assembly is manufactured by joining the membrane electrode assembly, the resin sheet, and the gas diffusion layer via an adhesive applied on the membrane electrode assembly. Patent Document 1 discloses a technique related to the application of an adhesive onto a membrane electrode assembly, in which a metal mask having different shapes of openings on the upper surface and lower surface is used and an adhesive is applied by a screen printing method. ing.

JP2015-231686A

  When the inventor applies an adhesive on the membrane electrode assembly, if there is a difference in the shape of the opening between the upper surface and the lower surface of the mask used in the screen printing method, for example, the mask and the membrane electrode assembly are formed. It has been found that the adhesive does not easily enter the acute angle region, and bubbles are generated between the adhesive and the resin sheet when the resin sheet and the gas diffusion layer are placed on the adhesive.

  The present invention has been made in view of the above problems, and a membrane electrode gas capable of suppressing bubbles generated when a resin sheet is placed on an adhesive applied on a membrane electrode assembly. A method for producing a diffusion layer assembly is provided.

  In the method of manufacturing a membrane electrode gas diffusion layer assembly according to the present invention, a membrane electrode gas diffusion layer assembly is manufactured by disposing a resin sheet and a gas diffusion layer on the membrane electrode assembly. A method of applying an adhesive on the membrane electrode assembly, and a step of placing the resin sheet and the gas diffusion layer on the adhesive, the membrane electrode assembly In the step of applying the adhesive, a frame-shaped first mask and a rectangular second mask connected to the inside of the first mask via a mesh and having a thickness smaller than the first mask, A screen mask provided on the membrane electrode assembly, the first mask and the second mask are brought into contact with the membrane electrode assembly, and the mesh is inclined with respect to the membrane electrode assembly. Apply adhesive.

  In the method for manufacturing a membrane electrode gas diffusion layer assembly according to the present invention, in the step of applying an adhesive on the membrane electrode assembly, the frame-shaped first mask is connected to the inside of the first mask via a mesh. A second mask having a rectangular shape thinner than the first mask is disposed on the membrane electrode assembly, and the mesh is formed by bringing the first mask and the second mask into contact with the membrane electrode assembly. An adhesive is applied in a state of being inclined with respect to the electrode assembly. Therefore, bubbles generated between the adhesive and the resin sheet when the resin sheet is placed on the adhesive applied on the membrane electrode assembly can be suppressed.

  According to the present invention, when the resin sheet is placed on the adhesive applied on the membrane electrode assembly, bubbles generated between the adhesive and the resin sheet can be suppressed.

It is a membrane electrode gas diffusion layer assembly manufactured by the manufacturing method of the membrane electrode gas diffusion layer assembly according to the embodiment. It is a top view which shows the state which has arrange | positioned the screen plate used for the manufacturing method of the membrane electrode gas diffusion layer assembly concerning embodiment to MEA. It is front sectional drawing which follows the IIB-IIB line | wire of FIG. 2A. It is front sectional drawing which shows the state which has apply | coated the adhesive agent on MEA using the screen plate concerning embodiment. It is a cross-sectional perspective view which shows the state by which the adhesive agent was apply | coated on MEA concerning embodiment. It is a cross-sectional perspective view which shows the state which mounted the resin sheet on the top part of the adhesive agent apply | coated on MEA concerning embodiment. It is front sectional drawing which shows the process of applying and arrange | positioning a resin sheet on MEA concerning embodiment. It is front sectional drawing which shows the process of laminating | stacking GDL on MEA concerning embodiment. It is a section perspective view showing the state where GDL was arranged under pressure on MEA concerning an embodiment.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.
As a matter of course, the right-handed xyz coordinates shown in FIGS. 1 to 2H are convenient for explaining the positional relationship of the constituent elements. Usually, the z-axis plus direction is vertically upward, and the xy plane is a horizontal plane.

<Embodiment>
FIG. 1 shows a membrane electrode gas diffusion layer assembly (MEGA) manufactured by the method for manufacturing a membrane electrode gas diffusion layer assembly according to the present embodiment. FIG. 1 shows the MEGA 10 on the cathode side (z-axis direction positive side). As shown in FIG. 1, the MEGA 10 in this embodiment includes a membrane electrode assembly (MEA) 11 and a gas diffusion layer (Gas Diffusion) provided on the cathode side (z-axis direction positive side) of the MEA 11. Layer, GDL) 12 and resin sheet 13. The MEA 11, the GDL 12, and the resin sheet 13 are joined via the adhesive B. Further, a single cell is formed by stacking a separator on the MEGA 10. Also, a stack of a plurality of single cells is a fuel cell stack used for a fuel cell.

  In this embodiment, the MEGA on the cathode side will be described. However, the structure for joining the MEA, the GDL, and the resin sheet via an adhesive only needs to be provided on either the cathode side or the anode side. . That is, the GDL and the resin sheet may be joined to the MEA with the positive side in the z-axis direction as the anode side. In this case, the “cathode” and “anode” of each component are reversed. Similarly to the cathode side, on the anode side, the MEA, the anode side GDL, and the resin sheet may be joined via an adhesive. In other words, the structure in which the GDL and the resin sheet are bonded to the MEA via the adhesive may be provided on one side of the MEA, that is, either the cathode side or the anode side. You may have on the anode side.

  GDL12 can be comprised using the electroconductive member (For example, a carbon porous body and a metal porous body) which has gas permeability. Moreover, a separator can be comprised using metal materials, such as titanium, for example. The resin sheet 13 can be a flexible thermosetting resin or the like. For the adhesive B, for example, an ultraviolet curable resin containing polyisobutylene or the like can be used.

  Hereinafter, the manufacturing method of the membrane electrode gas diffusion layer assembly according to the present embodiment will be described with reference to FIGS. 2A to 2H.

<Application of adhesive (FIGS. 2A to 2D)>
Hereinafter, with reference to FIG. 2A-FIG. 2D, the process of apply | coating an adhesive agent on MEA11 using a screen printing method in order to join MEA11, GDL12, and the resin sheet 13 is demonstrated.

  FIG. 2A is a plan view showing a state in which a screen plate used in the manufacturing method of the membrane electrode gas diffusion layer assembly according to the present embodiment is arranged on the MEA. First, the screen plate 20 will be described with reference to FIG. 2A. As shown in FIG. 2A, the screen plate 20 includes a mesh 23 stretched on a plate frame F, a frame-shaped first mask 21 and a rectangular second mask 22 formed by coating the mesh 23 with an emulsion. And a squeegee S. In other words, the frame-shaped first mask 21 and the rectangular second mask 22 are arranged via the mesh 23.

  In the application of the adhesive using the screen printing method, first, the screen plate 20 is arranged on the MEA 11 and the adhesive B is arranged along the surface where the squeegee S and the first mask 21 are in contact. Next, the squeegee S is brought into line contact with the surfaces of the first mask 21, the second mask 22, and the mesh 23, and the adhesive B is pushed out of the mesh 23 by moving horizontally while applying pressure (in the positive x-axis direction). Then, the adhesive B is applied onto the MEA 11. In other words, by masking a region where the adhesive B is not applied to the MEA 11 and separating the mask after the adhesive B is applied, the adhesive B can be applied in a frame shape on the MEA 11.

  2B is a front cross-sectional view taken along the line IIB-IIB in FIG. 2A. As shown in FIG. 2B, since the plate frame F of the screen plate 20 is held by a clamp (not shown) or the like, the screen plate 20 and the MEA 11 are separated from each other before the application of the adhesive B is started.

  As shown in FIG. 2B, the thickness of the second mask 22 is thinner than the thickness of the first mask 21. In other words, the thickness of the emulsion applied to the mesh 23 stretched on the plate frame F is smaller in the second mask 22 than in the first mask 21. For example, the thickness of the emulsion applied to the second mask 22 is 10 to 50 μm thinner than the thickness of the emulsion applied to the first mask 21.

  The squeegee S is flexible and is made of, for example, rubber. As described above, the squeegee S makes line contact with the first mask 21, the second mask 22 and the mesh 23, and moves in parallel (pressure in the positive direction of the x-axis, white arrow) while pressing each surface. Therefore, as shown in FIG. 2B, the squeegee S at the original position is in a state where the surface in contact with the first mask 21 is bent.

  FIG. 2C is a front sectional view showing a state in which an adhesive is applied on the MEA using the screen plate according to the present embodiment. As shown in FIG. 2C, when the surfaces of the first mask 21, the second mask 22 and the mesh 23 are horizontally moved (x-axis positive direction, white arrow) while being pressurized using the squeegee S, the first mask 21 And the 2nd mask 22 contacts MEA11. As described above, the second mask 22 is thinner than the first mask 21, and the mesh 23 is inclined with respect to the MEA 11. When the adhesive 23 is applied to the MEA 11 in a state where the mesh 23 is inclined with respect to the MEA 11, the applied adhesive B has an upper surface (the xy plane on the z-axis positive side) with respect to the MEA 11 as in the shape of the mesh 23. Will be inclined.

  FIG. 2D is a cross-sectional perspective view showing a state in which an adhesive is applied on the MEA according to the present embodiment. As shown in FIG. 2D, a frame-shaped adhesive B is applied on the MEA 11. In the present embodiment, as described above, the adhesive B is applied in a state where the first mask 21 and the second mask 22 are brought into contact with the MEA 11 and the mesh 23 is inclined with respect to the MEA 11. Therefore, the applied frame-shaped adhesive B is applied to the MEA 11 in an inclined state from the outer side of the frame shape toward the inner side. In other words, each side of the adhesive B is formed in a substantially triangular prism shape.

<Lamination of resin sheets (FIGS. 2E and 2F)>
Next, the process of laminating the resin sheet 13 on the MEA 11 will be described with reference to FIGS. 2E and 2F. FIG. 2E is a cross-sectional perspective view showing a state in which a resin sheet is placed on top of the adhesive applied on the MEA according to the present embodiment. As shown in FIG. 2E, the resin sheet 13 is placed on the top of the adhesive B inclined with respect to the MEA 11.

  Next, the MEA 11 and the resin sheet 13 are bonded via the adhesive B. FIG. 2F is a front sectional view showing a step of placing a resin sheet under pressure on the MEA according to the present embodiment. 2F, pressure is applied to the resin sheet 13 in the vertically downward direction (z-axis negative direction, white arrow), and the MEA 11 and the resin sheet 13 are bonded via the adhesive B. As shown in FIG. 2F, when pressure is applied to the resin sheet 13, the adhesive B is pushed out toward the center of the MEA 11 (black arrow), and is in a raised state.

  2E and 2F, the resin sheet 13 has a flat plate shape, and the lower surface (z-axis negative side xy surface) is placed horizontally with respect to the MEA 11, but the resin sheet 13 has flexibility. . Therefore, when placing the resin sheet 13 on the adhesive B, the resin sheet 13 can be arranged along the inclination of the adhesive B, pressure is applied, and finally, the resin sheet 13 can be arranged horizontally with respect to the MEA 11.

<Lamination of GDL (FIGS. 2G and 2H)>
Next, with reference to FIG. 2G and FIG. 2H, the process of laminating | stacking GDL12 on MEA11 is demonstrated. FIG. 2G is a front sectional view showing a step of stacking GDL on the MEA according to the present embodiment. As shown in FIG. 2G, the GDL 12 is placed on the top of the adhesive B in a state of rising in the center direction of the MEA 11 in the step of laminating the resin sheets 13. Next, pressure is applied to the GDL 12 in a vertically downward direction (z-axis negative direction, white arrow), and the MEA 11 and the GDL 12 are disposed via the adhesive B. GDL12 concerning this Embodiment is a rectangular shape smaller than the inner frame of the resin sheet 13, and the GDL12 and the resin sheet 13 are spaced apart and arrange | positioned.

  FIG. 2H is a cross-sectional perspective view showing a state in which the GDL placed on the MEA according to the present embodiment is placed under pressure. As shown in FIG. 2H, the GDL 12 is disposed horizontally with respect to the MEA 11 with the adhesive B interposed therebetween. The bottom surface of the GDL 12 (z-axis negative side xy plane) and the bottom surface of the resin sheet 13 (z-axis negative side xy plane) are on the same plane and are disposed so as to be horizontal to the MEA 11. It is preferable to do. Further, since the thickness of the GDL 12 is thinner than the thickness of the resin sheet 13, the GDL 12 is disposed with the upper surface (xy plane on the z-axis positive side) of the GDL 12 recessed from the upper surface (z-axis positive side of the xy plane). The

  In the case where the adhesive B is an ultraviolet curable resin, the resin sheet 13 and the GDL 12 are respectively placed on the MEA 11 by applying pressure, and then the ultraviolet rays are irradiated to cure the adhesive B. The resin sheet 13 is bonded via the adhesive B.

  As in the prior art, when applying an adhesive on a membrane electrode assembly, if there is a difference in the shape of the opening between the upper surface and the lower surface of the mask used in the screen printing method, for example, the mask and the membrane electrode assembly It is difficult for the adhesive to enter the formed acute angle region, and it becomes difficult to apply the adhesive to the target region or shape, and when the resin sheet and the gas diffusion layer are placed on the adhesive, There was a problem that air bubbles were generated between the resin sheet and the resin sheet.

  In the present embodiment, the adhesive is applied in a state where the mesh is inclined with respect to the membrane electrode assembly. The applied frame-shaped adhesive is applied to the membrane electrode assembly in an inclined state from the outside to the inside of the frame, so that when the resin sheet is placed on the adhesive, the adhesive and the resin sheet Bubbles generated during the period can be suppressed. In addition, since air bubbles generated between the adhesive and the resin sheet can be suppressed, it is not necessary to apply pressure for removing the air bubbles at the time of joining, and the manufacturing process can be reduced. Furthermore, when bubbles are mixed between the adhesive and the resin sheet, the adhesive strength is reduced due to the bubbles. Therefore, the membrane electrode assembly and the resin sheet are made larger than originally required, and the adhesive It was necessary to compensate for the decrease in adhesive strength by enlarging the bonding surface. On the other hand, in the present embodiment, since the generation of bubbles generated between the adhesive and the resin sheet can be suppressed, the membrane electrode gas diffusion layer assembly can be produced with an appropriate size. In other words, the volume of the membrane electrode gas diffusion layer assembly can be reduced.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 Membrane electrode gas diffusion layer assembly 11 Membrane electrode assembly 12 Gas diffusion layer 13 Resin sheet 20 Screen plate 21 First mask 22 Second mask 23 Mesh B Adhesive F Plate frame S Squeegee

Claims (1)

A method for producing a membrane electrode gas diffusion layer assembly comprising a resin sheet and a gas diffusion layer disposed on a membrane electrode assembly to produce a membrane electrode gas diffusion layer assembly,
Applying an adhesive on the membrane electrode assembly;
Placing the resin sheet and the gas diffusion layer on the adhesive, and
In the step of applying an adhesive on the membrane electrode assembly,
A screen mask comprising a frame-shaped first mask and a rectangular second mask that is connected to the inside of the first mask via a mesh and is thinner than the first mask is disposed on the membrane electrode assembly. The adhesive is applied in a state where the first mask and the second mask are brought into contact with the membrane electrode assembly and the mesh is inclined with respect to the membrane electrode assembly.
Manufacturing method of membrane electrode gas diffusion layer assembly.

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