JP2006049241A - Adhesive sheet for solid oxide fuel cell and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive sheet for solid oxide fuel cell capable of obtaining stable battery characteristics, and a manufacturing method of the same. <P>SOLUTION: An adhesive agent layer 3 is formed by printing it on a base plate 2 having a peeling property, and afterwards, an electrode forming material or an electrolyte forming material, an organic resin binder, and a paste 4, in which a solvent is mixed, are printed on the adhesive agent layer 3, and dried. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pressure-sensitive adhesive sheet for a solid oxide fuel cell used for a solid oxide fuel cell (SOFC) and a method for producing the same.

  Conventionally, in general, a solid oxide fuel cell has a structure in which a fuel electrode is disposed on one surface of an electrolyte and an air electrode is disposed on the other surface through an electrolyte made of a solid oxide having oxygen ion conductivity. By supplying fuel gas to the electrode side and supplying oxidant gas to the air electrode side, it is possible to generate an electrochemical reaction and obtain electric power.

  The electrode of such a solid oxide fuel cell is generally a wet method in which the electrode material used in the solid oxide fuel cell is made into a paste, applied to an electrolyte, and then fired to form a film. . As such a wet method, a screen printing method, a spray coating method, a dipping method, an electrophoretic electrodeposition method and the like are known.

  As another method for forming an electrode, there is a dry method, and film forming methods such as CVD, EVD, and sputtering are known.

  However, in producing a solid oxide fuel cell, in order to ensure battery performance, the electrode or electrolyte film thickness and the required electrode itself are not affected by the electrode, electrolyte material, surface condition, etc. Therefore, it is necessary to control and produce the planar shape and the like as designed according to the intended use.

  In particular, when manufacturing a cylindrical SOFC, it is necessary to form an electrode on a curved surface, but it is difficult to apply by a dry method or a screen printing method, and can be applied by a dipping method. Partial formation is difficult, and the battery performance varies further.

  Furthermore, SOFCs are generally formed by the above-mentioned method for each sheet after forming an electrode or an electrolyte substrate, and there is a problem that the production efficiency is not good.

  Then, in view of the said conventional problem, this invention aims at providing the adhesive sheet for solid oxide fuel cells from which the stable battery performance is obtained, and its manufacturing method.

  Another object of the present invention is to provide a pressure-sensitive adhesive sheet for a solid oxide fuel cell and a method for producing the same, which can form an electrode on a curved surface while suppressing variation in battery performance and production cost.

  Furthermore, an object of this invention is to provide the adhesive sheet for solid oxide fuel cells which can improve production efficiency, and its manufacturing method.

  In order to achieve the above object, a first method for producing a pressure-sensitive adhesive sheet for a solid oxide fuel cell according to the present invention comprises: printing an adhesive layer on a peelable substrate and drying the adhesive layer; A paste in which an electrode forming material or an electrolyte forming material, an organic resin binder, and a solvent are mixed is printed and dried.

  The second manufacturing method of the pressure-sensitive adhesive sheet for a solid oxide fuel cell according to the present invention is the first manufacturing method in which a protective layer made of an organic resin is printed on the layer obtained by drying the paste. The protective layer is formed and dried.

  Furthermore, the third production method of the pressure-sensitive adhesive sheet for a solid oxide fuel cell according to the present invention is the first production method or the second production method, wherein the peelable substrate is a film made of a synthetic resin or The surface of the sheet is subjected to matting treatment.

  Furthermore, the fourth production method of the pressure-sensitive adhesive sheet for a solid oxide fuel cell according to the present invention is the first production method or the second production method, wherein the peelable substrate is a synthetic resin film. Alternatively, a release layer is formed on the surface of a sheet, paper, or synthetic paper.

  Moreover, according to the 5th manufacturing method of the adhesive sheet for solid oxide fuel cells which concerns on this invention, in the said 1st-4th manufacturing method, the printed layer of the said paste is made into a multilayer. Features.

  Moreover, in order to achieve the said objective, this invention further provides the adhesive sheet for solid oxide fuel cells manufactured by the said any one of the 1st-5th manufacturing method.

  According to the present invention, material loss can be reduced, cost can be reduced, and product performance can be prevented from being varied between lots, and work can be saved when attaching electrodes or electrolytes to adherends.

  In addition, according to the present invention, it is possible to provide a flexible sheet for use in forming an electrode and an electrolyte that do not crack during distribution, and it is easy to form on a curved surface as well as a flat surface. The battery can be used in two types, a flat plate type and a cylindrical type.

  Furthermore, according to the present invention, the electrode or the electrolyte can be mass-produced at a time by a roll-to-roll method, so that the production efficiency is improved.

  The solid oxide fuel cell pressure-sensitive adhesive sheet and the production method according to the present invention will be described below with reference to the drawings. 1-5 is a figure which shows the adhesive sheet for solid oxide fuel cells manufactured by the adhesive sheet for solid oxide fuel cells which concerns on this invention. In addition, the same code | symbol was attached | subjected to the same component through the whole figure.

  First, a first embodiment of a solid oxide fuel cell pressure-sensitive adhesive sheet according to the present invention will be described below with reference to FIGS.

  The pressure-sensitive adhesive sheet 1 for a solid oxide fuel cell is formed by printing and forming an adhesive layer 3 on a peelable substrate 2 and then drying the electrolyte layer forming material, organic resin binder, and solvent on the adhesive layer 3. It is obtained by printing the mixed paste 4 and drying it. Instead of the electrolyte forming material, an electrode forming material may be used.

  In the first embodiment, the peelable substrate 2 uses a synthetic resin sheet or film. The synthetic resin sheet or film used for the peelable substrate 2 is polyethylene resin, polypropylene resin, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (ABS resin), polyvinyl chloride resin. Resins, fluorine resins, poly (meth) acrylic resins, polycarbonate resins, polyester resins such as polyethylene terephthalate or polyethylene naphthalate, polyamide resins such as various nylons, polyimide resins, polyamideimide resins, polyaryls It can be formed from phthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyethersulfone resin, polyurethane resin, acetal resin, cellulose resin, and other known resin materials. That.

  From the viewpoints of flexibility, mechanical properties, chemical properties, etc., the material of the peelable substrate 2 is made of polyethylene resin, polypropylene resin, or polyester resin, which is lightweight, rich in processability and easy to handle. As preferred.

  The pressure-sensitive adhesive sheet 1 for a solid oxide fuel cell according to the present invention is circulated in an unsintered state, and the peelable substrate 2 needs a certain level of strength. It is preferable that it is -100micrometer.

  It is preferable that the peelable substrate 2 is improved in peelability by performing a matting treatment. The matting treatment means that the surface is given a fine unevenness to make it matt. As the matting treatment, for example, a sand blasting method in which irregularities are physically formed on the surface of a base material formed of a synthetic resin, a method of forming fine particles in the base material, or the like can be employed.

  Specific examples of the method for inclusion in the peelable substrate 2 include silica, titanium oxide, calcium carbonate, talc, kaolinite, mica and other inorganic fine particles, acrylonitrile polymer, acrylate polymer, polystyrene and the like. Polymer particles of a hydrophobic resin, polymer particles of a hydrophilic resin such as polyacrylic acid, polyacrylamide, polyamide, polyvinyl alcohol, and gelatin, or a finely pulverized product or emulsion of these resins are included at the time of molding the substrate. These fine particles and finely pulverized products preferably have a diameter of 1 μm or less.

  As an adhesive for forming the adhesive layer 3, a rubber adhesive, an acrylic adhesive using acrylic acid or an acrylic ester as a starting material, or a known adhesive such as a silicone resin adhesive is used. can do. The adhesive layer 3 is printed to a thickness of 1 to 50 μm, for example, by a screen printing method.

  The drying conditions of the adhesive layer 3 can be 40 to 130 ° C. and 5 to 60 minutes, for example. If it is insufficiently dried, the residual amount of the solvent component that dilutes the adhesive will increase and the adhesive strength will decrease. If it is too dry, curling will occur due to thermal shrinkage of the peelable substrate. This is because it is difficult to handle and causes troubles in the production of the pressure-sensitive adhesive sheet, and when the electrode or electrolyte is printed in a subsequent process, the electrode or the electrolyte is likely to crack.

  As the electrolyte forming material, those known as electrolytes for solid oxide fuel cells can be used. And oxygen ion conductive ceramic materials such as zirconia-based oxides containing scandium and yttrium can be used.

  The organic resin binder to be mixed with the electrolyte forming material needs to be burned / decomposed / vaporized at a low temperature in the firing process, and is made of an acrylic resin, a styrene resin, an ethyl cellulose derivative, or a styrene acrylic copolymer, Used alone or in combination.

  As the solvent mixed with the electrolyte forming material and the organic resin binder, a solvent that does not dissolve the resin binder easily but only swells is preferably selected. In general, ketones, esters, ethers, amides and the like can be used, and mixtures thereof can be used. Specifically, isopropanol, normal propanol, diacetone alcohol, glycol diacetate, methyl cellosolve, Carbitol, cyclohexane, terpineol, etc. can be used. Also, high boiling point compounds such as glycerin, dibutyl phthalate, dioctyl phthalate can be used.

  If necessary, the electrolyte forming material and the organic resin binder may further include a plasticizer, a viscosity modifier, a dispersant, an antioxidant, an antistatic agent, a crosslinking agent, a curing agent, a filler, a lubricant, a foaming agent, One or more of reinforcing agents such as calcium carbonate to enhance the strength of the layer itself, and other additives can be added to the ink having a viscosity suitable for the coating method and printing suitability. Adjust.

  In particular, as one method for imparting flexibility, for example, there is a method in which a plasticizer is added and a long chain compound of an organic resin binder is left as an unreacted substance in a cured product. As the plasticizer, for example, dibutyl phthalate, ethylene glycol ester of organic acid, ethylene oxide adduct of tetrahydrofurfuryl alcohol, and the like can be used.

  As another method of imparting flexibility, a method of adding a flexibility imparting agent having an epoxy group and reacting the flexibility imparting agent with an organic resin binder (long chain compound) at the time of curing. There is also. When such a flexibility-imparting agent is mixed with a long chain compound, strong adhesive force and viscoelasticity can be obtained by the epoxy group contained in the flexibility-imparting agent.

  Furthermore, as another method of imparting flexibility, there is also a method of selecting and using a diluted solution. Examples of such a diluent solvent include butyl glycidyl ether, acrylic glycidyl ether, diglycidyl ether, butanediol glycidyl ether and the like. It can be illustrated.

  The paste in which the electrolyte forming material, the organic resin binder, and the solvent are mixed can be printed to a desired thickness of 1 to 100 μm by screen printing. The printed paste is dried, for example, by leaving it at 40 to 130 ° C. for 5 to 60 minutes. This is because if the drying is insufficient, defects may occur in the printed layer at the time of winding, and if it is too dry, curling due to heat shrinkage will occur and it will be difficult to handle, and it will interfere with the production of the adhesive sheet. . A multilayer paste can also be formed by printing the same kind of paste on the dried layer of the paste and drying it (not shown).

  When the solid oxide fuel cell pressure-sensitive adhesive sheet produced as described above is used, as shown in FIG. 2, the peelable substrate 2 is peeled off and adhered to an electrode substrate as an adherend, and then fired. Tie.

  When an electrode forming material is used instead of the electrolyte forming material, the electrode forming material includes a fuel electrode forming material and an air electrode forming material.

  The fuel electrode forming material and the air electrode forming material can be formed by mixing a ceramic powder material with a binder or the like into a paste, drying and sintering. The average particle size of the ceramic powder used at this time is preferably 10 nm to 100 μm, more preferably 50 nm to 50 μm, and particularly preferably 100 nm to 10 μm. In addition, an average particle diameter can be measured according to JISZ8901, for example.

  As the fuel electrode forming material, for example, a mixture of a metal catalyst and a ceramic powder material made of an oxide ion conductor can be used. As the metal catalyst used at this time, a material that is stable in a reducing atmosphere, such as nickel, iron, cobalt, or a noble metal (platinum, ruthenium, palladium, etc.) and has hydrogen oxidation activity can be used. In addition, as the oxide ion conductor, one having a fluorite structure or a perovskite structure can be preferably used. Examples of those having a fluorite structure include ceria-based oxides doped with samarium, gadolinium, and the like, and zirconia-based oxides containing scandium and yttrium. In addition, examples of those having a perovskite structure include lanthanum galide oxides doped with strontium and magnesium. Among the above materials, the fuel electrode 4 is preferably formed of a mixture of an oxide ion conductor and nickel. The mixed form of the ceramic material made of the oxide ion conductor and nickel may be a physical mixed form or a form of powder modification to nickel. Moreover, the ceramic material mentioned above can be used individually by 1 type or in mixture of 2 or more types. Moreover, as a fuel electrode forming material, a metal catalyst can be used alone.

As the air electrode forming material, for example, a metal oxide ceramic powder material made of Co, Fe, Ni, Cr, Mn or the like having a perovskite structure or the like can be used. Specifically, (Sm, Sr) CoO ₃ , (La, Sr) MnO ₃ , (La, Sr) CoO ₃ , (La, Sr) (Fe, Co) O ₃ , (La, Sr) (Fe, Co , Ni) O _{3 and the} like, and (La, Sr) MnO ₃ is preferable. The ceramic material mentioned above can be used individually by 1 type or in mixture of 2 or more types.

  Also when the fuel electrode forming material and the air electrode forming material are used, the organic resin binder and the solvent can be made into a paste by mixing the same materials as those used for the electrolyte forming material.

  The solid oxide fuel cell pressure-sensitive adhesive sheet containing the electrode-forming material thus obtained peels the peelable substrate 2, adheres to the electrolyte substrate 5, and is sintered. As the electrolyte base material 5, it is possible to use an electrolyte material powder obtained by uniaxial press molding, isostatic press molding, and then sintering at a predetermined temperature.

  In the above description, the printing method is not limited to the screen printing method, but the floating knife coat method, the knife over roll coat method, the inverted knife coat method, and the squeeze roll coat method. Method, reverse roll coat method, roll coat method, gravure roll coat method, kiss roll coat method, air blade coat method, dip coat method, flow coat -Coating method, spin coating method, spray coating method, bar coating method, curtain coating method, etc., or gravure printing, offset printing, transfer printing A wet printing method such as can be used.

  Next, a second embodiment of the solid oxide fuel cell pressure-sensitive adhesive sheet according to the present invention will be described with reference to FIG.

  The second embodiment is different from the first embodiment in that after the paste is dried, a protective layer 6 is formed on the layer by printing and dried, and the other points are the same as in the first embodiment. It is the same as the form.

  The protective layer 6 prevents the generation of defective products due to scratches on the layer containing the electrode forming material or the electrolyte forming material when handling the solid oxide fuel cell pressure sensitive adhesive sheet, and the solid oxide fuel cell pressure sensitive adhesive sheet during transfer It is necessary to combust / decompose / vaporize at a low temperature during the firing process, and it is necessary to prevent acrylic resin, styrene resin, ethyl cellulose derivative, or styrene acrylic. It consists of a polymer and is used alone or in combination. As the solvent or dispersion medium for dispersing these resins, ketones, esters, ethers, amides and the like can be used widely, and mixtures thereof can be used. Specifically, isopropanol, normal propanol, dioxane, and the like can be used. Acetone alcohol, glycol diacetate, methyl cellosolve, carbitol, cyclohexane, terpineol and the like can be used. Also, high boiling point compounds such as glycerin, dibutyl phthalate, dioctyl phthalate can be used. The protective layer 6 can also be formed by the wet printing method described above.

  Next, 3rd Embodiment of the adhesive sheet for solid oxide fuel cells which concerns on this invention is described, referring FIG.

  The third embodiment is different from the first embodiment in that the peelable substrate 2 is a paper, a synthetic resin sheet or film, or a laminate of a synthetic paper 2a and a release layer 2b. Is the same as in the first embodiment.

  Examples of the paper-based material used for the peelable substrate 2 include thin paper, high-quality paper, Japanese paper, kraft paper, and synthetic paper. As the release layer 2b laminated thereon, for example, water-soluble polyvinyl alcohol Examples thereof include gelatin, epoxy resin, melamine resin, phenol resin, fluororesin, silicone resin, acrylic resin such as acrylic polyol, ester resin, urethane resin, polyamide resin such as nylon, and cellulose resin. The synthetic resin sheet or film used for the peelable substrate 2 can use the same material as the peelable substrate of the first embodiment.

In addition, the release layer 2b is formed by using an aromatic hydrocarbon such as toluene and xylene, a ketone such as methyl ethyl ketone and methyl isobutyl ketone, an ester such as ethyl acetate and methyl acetate, or an alcohol solvent such as propanol and butanol as described above. What was adjusted to predetermined viscosity (10-10 < ⁵ > Pa * s) by melt | dissolving resin can be printed on paper or synthetic paper by various printing methods, and can be formed by drying.

  As shown in FIG. 4, the solid oxide fuel cell pressure-sensitive adhesive sheet of the third embodiment can further be provided with a protective layer 6 similar to that shown in the second embodiment.

  In addition, said peeling layer 2b can also be formed in the surface of the peelable base material made from a synthetic resin in the said 1st Embodiment.

  Hereinafter, the present invention will be further clarified by examples.

  A roll-shaped PET film (thickness 50 μm) subjected to matting treatment is drawn out, and a commercially available acrylic adhesive is applied thereon as an adhesive layer so as to have a thickness of 5 μm by gravure printing, and about 50 ° C. Dried at a temperature of. Thereafter, 60 parts by weight of NiO powder (particle size: 0.01 to 10 μm, average particle size: 1 μm) as a fuel electrode forming material is dispersed in 20 parts by weight of toluene, and this is used as 20 parts by weight of cellulose resin and plasticizer. A paste was prepared by mixing with 6 parts by weight of dibutyl phthalate. This paste was applied to a film thickness of 50 μm by a knife coating method, and further, an acrylic resin was applied thereon as a protective layer to a film thickness of 10 μm by a knife coating method at 50 ° C. It was made to dry and the adhesive sheet for solid oxide fuel cells was created.

  The obtained pressure-sensitive adhesive sheet for a solid oxide fuel cell was flexible and was excellent in handling because it did not crack even when bent to a radius of curvature of about 10 cm.

1 is a longitudinal sectional view showing a first embodiment of a pressure-sensitive adhesive sheet for a solid oxide fuel cell according to the present invention. It is explanatory drawing which shows the usage example of the adhesive sheet for solid oxide fuel cells of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the adhesive sheet for solid oxide fuel cells which concerns on this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the adhesive sheet for solid oxide fuel cells which concerns on this invention. It is a longitudinal cross-sectional view which shows the change aspect of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Adhesive sheet for solid oxide fuel cells 2 Peelable base material 2b Peeling layer 3 Adhesive layer 4 Mixed paste 5 Substrate 6 Protective layer

Claims (6)

After the adhesive layer is printed and formed on the peelable substrate and dried, a paste in which the electrode forming material or the electrolyte forming material, the organic resin binder, and the solvent are mixed is printed and dried on the adhesive layer. A method for producing a pressure-sensitive adhesive sheet for a solid oxide fuel cell. 2. The method for producing a pressure-sensitive adhesive sheet for a solid oxide fuel cell according to claim 1, wherein a protective layer made of an organic resin is formed on the layer obtained by drying the paste by printing, and the protective layer is dried. . 3. The production of a pressure-sensitive adhesive sheet for a solid oxide fuel cell according to claim 1, wherein the peelable substrate is subjected to matting treatment on the surface of a synthetic resin film or sheet. Method. 3. The solid oxide fuel cell according to claim 1, wherein the peelable substrate has a release layer formed on the surface of a synthetic resin film or sheet, paper, or synthetic paper. 4. A method for producing an adhesive sheet. The method for producing a pressure-sensitive adhesive sheet for a solid oxide fuel cell according to any one of claims 1 to 4, wherein the paste has a multilayer printed layer. A pressure-sensitive adhesive sheet for a solid oxide fuel cell produced by the production method according to claim 1.

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