Patent ID: 6358436
Filing Date: 2002-03-19
Classification: H01C

Abstract:
An inorganic-metal composite body exhibiting PTC behavior at a trip point temperature ranging from 40Â° C.-300Â° C., comprising:an electrically insulating inorganic matrix having a room temperature resistivity of at least 1Ã—106 &OHgr;Â·cm; and electrically conductive particles uniformly dispersed in said matrix and forming a three-dimensional conductive network extending from a first surface of said body to an opposed second surface thereof, said particles consisting essentially of Bi and Sn; wherein the composite body has a room temperature resistivity of no more than 1 &OHgr;Â·cm and a high temperature resistivity of at least 100 &OHgr;Â·cm, and wherein said electrically conductive particles shrink by at least 0.5 vol % when melted.