PTC compositions

摘要

A PTC composition comprising at least one polymer, from 5% to 45% by volume of electrically conductive or semiconductive particles having a room temperature electric conductivity of at least 102 [s/m] dispersed in said polymer, and from 0.2% to 20% by volume of thermally conductive particles having a room temperature electric conductivity of no more than 10-3 [s/m] and a thermal conductivity of at least 20 [w/mxk] dispersed in said polymer. A PTC device using such a PTC composition has a high ratio of peak resistance to room temperature resistance, and exhibits high safety.