Directly heating type cathode and its manufacture

Abstract

Abstract PURPOSE:To prevent the exfoliation of alkaline earth metal oxide for lengthening life of a cathode by roughening the surface, where an alkaline earth metal oxide is to be coated, of a base by plating a metal composition composed primarily of Ni and Co. CONSTITUTION:The base 1 is coated with the photoresisto 4, and then the surface where an alkaline earth metal oxide is to be coated is covered with a negative film of a given pattern, exposed to light, developed, and then removed its partial photoresisto 4. Then, an Ni plating is applied on the surface where a pattern is formed and then the remaining photoresisto 4 is removed out to form the fine pattern 5 in which the Ni-plated layer is spotted, and the upside of the base 1 is roughened. Subsequently, the roughened surface is covered with the alkaline earth metal oxide 2 to form a cathode. Thus, the exfoliation of the alkaline earth metal oxide can be exactly prevented and therefore its life can be maintained for a long period of time.

Inventors

• 👤 Kazuo Sunahara

Bibliographic Details