| 摘要 |
1,054,613. Electrolyte capacitors. STANDARD TELEPHONES & CABLES Ltd. May 29, 1964 [May 31, 1963], No. 22304/64. Heading H1M. A solid electrolytic capacitor is formed by compacting titanium powder having a grain size of 10-100 microns into a plate shaped body. The body is provided with a titanium lead-in wire, sintered in vacuo at a temperature between 1200‹ C. and 1400‹ C. and the oxide film removed by etching in hydrofluoric acid. After washing, the body is then placed for several hours at room temperature in an aqueous oxidizing solution of nitric acid and hydrogen peroxide, and subsequently heated to 400-500‹ C. This pre-treated sintered body is then subjected to electrolytic forming processes, firstly in an aqueous electrolyte, e.g. an acid solution, at about 20‹ C. at 20 v., secondly at 350‹ C. in a mixture of salts, e.g. sodium nitrite, potassium nitrate, lithium nitrate, and thirdly at about 120-130‹ C. in an organic solution, e.g. glycol and ionogenes such as borates. Formation of the semi-conductor layer is effected by saturating the sintered body in vacuo with a mixture of manganese nitrate and manganese hydroxide and then heating in air to about 150-250‹ C. for manganese dioxide. In order to minimize the effects of cracking, this manganese dioxide layer is produced in partial layers, and between the formation of two such layers there is carried out a heating process in an alkaline reacting aqueous electrolyte. The electrode thus produced is finally coated with graphite serving as the base for a solderable metal. |
