Patent ID: 9502163
Filing Date: 2016-11-22
CPC Classification: H01C

Claim Text:
1. A PTC circuit protection device comprising: a PTC polymer material; and two electrodes attached to said PTC polymer material; wherein said PTC polymer material includes a polymer matrix and a conductive filler dispersed in said polymer matrix, said conductive filler including first titanium carbide particles and second titanium carbide particles; wherein said polymer matrix is made from a polymer composition that contains a base polyolefin and optionally a grafted polyolefin; wherein said first titanium carbide particles have an average Fisher sub-sieve particle size of less than 2.5 μm and a first particle size distribution that defines a particle size D10 of less than 1.6 μm, a particle size D50 of less than 4.5 μm, and a particle size D90 of less than 22.0 μm; wherein said second titanium carbide particles have an average Fisher sub-sieve particle size of less than 3.2 μm and a second particle size distribution that defines a particle size D10 of less than 2.5 μm, a particle size D50 of less than 6.5 μm, and a particle size D90 of less than 34.0 μm; and wherein said first titanium carbide particles have a residual oxygen content greater than 0.3 wt % based on a total weight of said first titanium carbide particles.