| 摘要 |
PURPOSE:To remarkably extend the life of a corona discharge electrode by coating a core wire with a noble metal or its alloy and subjecting the noble metal- coated corona discharge electrode to ultrasonic washing in water for a sufficient time to obtain the smooth surface of the electrode free from any contaminants. CONSTITUTION:A core wire 10, such as wire of tungsten, molymdenum, or stainless steel, is coated with a coating material 11, such as platinoids, gold, silver, or their alloys, to form a corona discharge electrode 6 of 2 layer structure, and it is surface treated by executing ultrasonic washing first in an org. solvent, such as trichloroethylene, to eliminate contaminants, such as metal soap, salt, fat, or amines, attached to the surface, further, ultrasonic washing in pure water for a sufficient time, and finally naturally or compulsorily drying it. When the electrode thus treated is fixed to the device and actuated, it is not deteriorated than the allowable level after the use for about 150hr and it is confirmed to be able to be used further more. |
