PTC THERMISTOR AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a PTC thermistor the resistance value of which changes at a small rate even when the thermistor is repeatedly used. SOLUTION: This PTC thermistor is formed by forming a sheet of a kneaded material obtained by kneading a prescribed amount of polymer and a prescribed amount of conductive material with each other after the polymer and conductive material are dried and baked, and by thermally press-fitting the sheet to a metallic member. The rate of change of the resistance value of this thermistor is suppressed so that the rate may become <=50% even when a 2V, 40A direct current is repeatedly impressed upon the thermistor for 1,000 cycles by impressing the current for 1 minute and ceasing the impression of the current for 5 minutes in each cycle.