| 摘要 |
1,114,491. Capacitors. EBASON DENKI KABUSHIKI KAISHA. 18 May, 1965 [20 May, 1964], No. 20990/65. Heading H1M. A capacitor electrode has a semi-permeable membrane on the surface thereof and in the case of an electrolytic capacitor, the membrane may be on the electrode bearing the anodized oxide layer. The membrane is formed from nitrocellulose, polyvinyl alcohol, polyethylene oxide, methylcellulose, alkali metal celluloses, acetyl cellulose, collodium oxides or gelatine by applying a solution, emulsion, suspension or dispersion to the electrode plate or by forming the membrane independently and then applying it to the plate. An ionic semi-permeable membrane may be formed by blending a pulverized or liquidized ion-exchange substance with one of the above substances, or by applying a solution of ion-exchange substance on the membranecovered base. The ion-exchange substance may be sulphonated polystyrene optionally containing quaternary basic groups. The membrane may also be formed by treating a solution of e.g. ethyl polysilicate applied to the electrode to form a bridged network of silica oxygen atoms. Other monomeric or polymeric organic silicon compounds may be used. The membrane may also incorporate inorganic oxides such as alumina, stannous oxide and titanium dioxide. As shown, an etched aluminium, tantalum, titanium or niobium foil la having layers 2 of oxide formed by anodizing in ammonium borate is the negative electrode of the capacitor. The positive electrode has semipermeable layers 3a and 3c of polyvinyl alcohol and 3b of nitrocellulose. The membranes are impregnated with electrolyte. In an alternative construction (Fig. 11, not shown) the semipermeable membrane is deposited directly on the oxide layer. |
