MANUFACTURING METHOD OF CHIP VARISTOR

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of a chip varistor which can improve fixing force of a plating layer formed on an external electrode and minimize lowering of an insulation resistance after plating treatment. SOLUTION: In this manufacturing method of a chip varistor, after an external electrode 13 and an insulation protection layer 14 are formed in a surface of a varistor unit 11 with an inner electrode 12 and the varistor unit 11 is subjected to heat treatment, a plating layer 15 is formed on the external electrode 13. Fixing force of a plating layer is improved by carrying out heat treatment before plating treatment. Desirable heating temperature in heat treatment is 450 to 550 deg.C and desirable temperature falling velocity is at most about 5 deg.C/min.