| 摘要 |
PURPOSE:To form a concentration detector having high reliability, high sensitivity, and simple construction by bonding a fuel retarding layer which retards permeation of fuel to an anode through a catalyst layer. CONSTITUTION:A fuel retarding layer 17b is arranged in an anode 17 through a catalyst layer 21. The fuel retarding layer 17b is formed by making carbon fibers in a paper form and immersing it in polytetrafluoroethylene fine particle dispersion, then baking them to control permeability and water repellent property. By this treatment, the premeability of fuel is controlled to, for example, 7X10<-6>mol/cm<2>, min., mol/l. A platinum family catalyst layer 21 is bonded to the fuel retarding layer 17b by placing the mixture obtained by kneading the catalyst layer material and polytetrafluoroethylene fine particle dispersion on one side of the layer 17b and baking. They are bonded to an anode comprising, for example, tantalum. The electrode is fixed with a frame so that fuel enters the electrode from the fuel retarding layer. |
