Functional sheet having reinforcing material
A reinforcing material-having functional sheet of a sheet-like functional material including a functional powder and a binder resin and, laminated thereon, a reinforcing sheet comprising a woven fabric or a non-woven fabric, which are bonded, wherein the basis weight of the reinforcing sheet, the fiber diameter of the fiber constituting the reinforcing sheet and the functional sheet thickness are in specific ranges. A sheet-like electrode for electric double layer capacitors, which electrode comprises a sheet-like electrode of carbon fine powder and a fluorine-containing polymer resin and, laminated thereon, the reinforcing sheet, and an electric double layer capacitor having this electrode. The functional sheet has strength and no elimination of the functional material powder, and also efficiently exhibits high functional properties. The sheet electrode can efficiently prepare electric double layer capacitors having strength, remarkably low internal resistance, slight lowering of charging and discharging capabilities, excellent durability and long lifetime.
1. A functional sheet having a reinforcing material comprising a sheet-like functional material comprised of a functional material powder and a binder resin, and, bonded thereto, a reinforcing sheet laminated on the sheet-like functional material,
wherein the reinforcing sheet comprises a woven or non-woven fabric cloth, having a basis weight of from 10 to 400 g/cm 2 , the fiber diameter of a fiber constituting the reinforcing sheet is from 10 to 150 μm.
2. The functional sheet having a reinforcing material according to claim 1 wherein the binder resin is an un-sintered polytetrafluoroethylene resin and contained in an amount of from 50 to 1% by weight based on the total amount of the sheet-like functional material.
3. The functional sheet having a reinforcing material according to claim 2 wherein the functional material powder comprises one kind or two or more kinds selected from active carbon, graphite, carbon black, bamboo charcoal, charcoal, titanium oxide, zinc oxide, lead oxide, silica, clay, metal powder, expanded graphite, water absorbing polymer, silica gel, mildew proofing agent and antibacterial agent.
4. The functional sheet having a reinforcing material according to claim 2 , which is an embossed reinforcing material-having functional sheet.
5. The functional sheet having a reinforcing material according to claim 1 wherein the functional material powder comprises one kind or two or more kinds selected from active carbon, graphite, carbon black, bamboo charcoal, charcoal, titanium oxide, zinc oxide, lead oxide, silica, clay, metal powder, expanded graphite, water absorbing polymer, silica gel, mildew proofing agent and antibacterial agent.
6. The functional sheet having a reinforcing material according to claim 5 , which is an embossed reinforcing material-having functional sheet.
7. The functional sheet having a reinforcing material according to claim 1 , which is an embossed reinforcing material-having functional sheet.
8. An electrode for electric double-layer capacitors comprising a sheet-like electrode material comprised of a carbon fine powder and a fluorine-containing polymer resin, and, bonded thereto, a reinforcing sheet, laminated on the sheet-like functional material,
wherein the reinforcing sheet comprises a woven or non-woven fabric cloth, having a basis weight of from 10 to 400 g/cm 2 , the fiber diameter of a fiber constituting the reinforcing sheet is from 10 to 150 μm.
9. The electrode for electric double-layer capacitors according to claim 8 wherein the reinforcing sheet comprises any one of a cloth, a mesh, a non-woven fabric cloth and an expand sheet, and has a thickness of from 0.01 to 1.0 mm.
10. The electrode for electric double-layer capacitors according to claim 9 wherein the carbon fine powder comprises active carbon and/or conductive carbon, and the fluoropolymer resin is polytetrafluoroethylene.
11. The electrode for electric double-layer capacitors according to claim 9 wherein the fluorine resin is contained in an amount of not more than 15% by weight in the electrode material.
12. An electric double-layer capacitor comprising the electrode for electric double-layer capacitors according to claim 9 .
13. The electrode for electric double-layer capacitors according to claim 8 wherein the carbon fine powder comprises active carbon and/or conductive carbon, and the fluoropolymer resin is polytetrafluoroethylene.
14. The electrode for electric double-layer capacitors according to claim 13 wherein the fluorine resin is contained in an amount of not more than 15% by weight in the electrode material.
15. An electric double-layer capacitor comprising the electrode for electric double-layer capacitors according to claim 13 .
16. The electrode for electric double-layer capacitors according to claim 8 wherein the fluorine resin is contained in an amount of not more than 15% by weight in the electrode material.
17. An electric double-layer capacitor comprising the electrode for electric double-layer capacitors according to claim 16 .
18. An electric double-layer capacitor comprising the electrode for electric double-layer capacitors according to claim 8 .