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A screen-printing paste as a starting material for fabricating a gas diffusion electrode through screen-printing includes at least one polymer, at least one metallic catalyst, and a high-boiling solvent. The polymer is a binder including poly(butyl acrylate)-polymethacrylate copolymer, a poly(vinyl

A screen-printing paste as a starting material for fabricating a gas diffusion electrode through screen-printing includes at least one polymer, at least one metallic catalyst, and a high-boiling solvent. The polymer is a binder including poly(butyl acrylate)-polymethacrylate copolymer, a poly(vinyl alcohol), and a poly(ethylene oxide). The polymer can be two polymers, a first being used for hydrophobicization and present in an amount of between 0 to 10% by weight based on a content of the metallic-catalyst, and a second being a binder. A screen-printing method of fabricating the electrode for a fuel cell includes forming a screen-printing layer having a thickness between 3 and 40 μm by applying the screen-printing paste to a base. The solvent and the polymer serve as a screen-printing medium. The screen-printing layer is baked to allow only residues of the solvent and the polymer to remain, which do not interfere with using the electrode in a fuel cell. The method uses a polybutylacrylate-polymethacrylate copolymer as a binder in the screen-printing paste.

대표청구항 ▼

1. A screen-printing method of fabricating a gas diffusion electrode for a fuel cell, which comprises: providing a screen-printing paste having: at least one polymer, the at least one polymer being at least one binder selected from the group consisting of a poly(butyl acrylate)-polymethacrylate

1. A screen-printing method of fabricating a gas diffusion electrode for a fuel cell, which comprises: providing a screen-printing paste having: at least one polymer, the at least one polymer being at least one binder selected from the group consisting of a poly(butyl acrylate)-polymethacrylate copolymer, a poly(vinyl alcohol), and a poly(ethylene oxide); at least one metallic catalyst; and a high-boiling solvent; forming a screen-printing layer having a thickness between 3 and 40 μm by applying the screen-printing paste to a base, the high-boiling solvent and the at least one polymer serving as a screen-printing medium for ensuring uniformity of the screen-printing layer; and baking the screen-printing layer to allow only residues of one of the high-boiling solvent and the at least one polymer to remain in the screen-printing layer, such residues not interfering with use of the gas diffusion electrode in a fuel cell. 2. The screen-printing method according to claim 1, wherein the at least one polymer is two polymers, a first of the two polymers is present in an amount of less than 10% by weight based on a content of the at least one metallic-catalyst, and a second of the two polymers is a binder, and which further comprises effecting hydrophobicization with the first of the two polymers. 3. The method according to claim 2, which further comprises performing the effecting step by effecting hydrophobicization in a screen-printing operation with the first of the two polymers. 4. The method according to claim 1, which further comprises effecting the hydrophobization with the at least one polymer in a separate procedural step after a screen-printing operation. 5. A screen-printing paste as a starting material for fabricating a gas diffusion electrode through screen-printing, comprising: a poly(butyl acrylate)-polymethacrylate copolymer binder; at least one metallic catalyst; and a high-boiling solvent. 6. The screen-printing paste according to claim 5 further comprising a second polymer selected from the group consisting of a poly(vinyl alcohol) and a poly(ethylene oxide), a first of said two polymers being used for hydrophobicization and being present in an amount of less than 10% by weight based on a content of said at least one metallic-catalyst, and a second of said two polymers being a binder. 7. A screen-printing method of fabricating a gas diffusion electrode for a fuel cell, which comprises: providing a screen-printing paste having: a poly(butyl acrylate)-polymethacrylate copolymer binder; at least one metallic catalyst; and a high-boiling solvent; forming a screen-printing layer having a thickness between 3 and 40 μm by applying the screen-printing paste to a base, the high-boiling solvent and the at least one polymer serving as a screen-printing medium for ensuring uniformity of the screen-printing layer; and baking the screen-printing layer to allow only residues of one of the high-boiling solvent and the at least one polymer to remain in the screen-printing layer, such residues not interfering with use of the gas diffusion electrode in a fuel cell. 8. The screen-printing method according to claim 7, which further comprises selecting a second polymer from the group consisting of a poly(vinyl alcohol) and a poly(ethylene oxide), a first of the two polymers being present in an amount of less than 10% by weight based on a content of the at least one metallic-catalyst, and a second of said two polymers being a binder effecting hydrophobicization with the first of the two polymers. 9. The method according to claim 8, which further comprises performing the effecting step by effecting hydrophobicization in a screen-printing operation with the first of the two polymers. 10. The method according to claim 7, which further comprises effecting the hydrophobization with the at least one polymer in a separate procedural step after a screen-printing operation.