| 摘要 |
PURPOSE:To obtain the titled exchange membrane which provides a lowered electrolytic voltage and a stable long operation of electrolysis, by roughening the surface of an ion exchange membrane by an ion etching treatment and coating the surface with an electrochemically active substance. CONSTITUTION:The surface of an ion exchange membrane is roughened to an etching depth of 0.1-20mu by ion-etching the surface by using, for example, a low-temperature plasma stream irradiator or a sputtering equipment operated by corona discharge and then the roughened surface is coated with an electrochemically active substance (e.g., graphite, Pt, TiO2), for example, by vacuum sputtering so as to form a coating of a thickness (calculated as a smooth surface coating thickness) of 0.05-5mu. By applcation of this coating, it becomes possible to lower an electrolytic voltage markedly without detriment to a high current efficiency and to operate electrolysis stably for a long time in the electrolysis of an aqueous solution of an alkali halide, especially electrolysis of salt. |
