Patent ID: 9455075
Filing Date: 2016-09-27
CPC Classification: H01C

Claim Text:
1. An over-current protection device comprising: first and second electrodes; and a multilayered structure disposed between said first and second electrodes and including first and second PTC polymer material layers that are stacked one above the other and that are bonded to each other; wherein said first PTC polymer material layer includes a first polymer matrix and a particulate conductive filler dispersed in said first polymer matrix, said first polymer matrix being made from a first polymer composition; and wherein said second PTC polymer material layer includes a second polymer matrix and a particulate conductive filler dispersed in said second polymer matrix, said second polymer matrix being made from a second polymer composition; wherein one of said first and second polymer compositions contains polyvinylidene fluoride and polyolefin and the other of said first and second polymer compositions contains polyolefin or polyvinylidene fluoride; wherein the other of said first and second polymer compositions is substantially free of polyvinylidene fluoride when containing polyolefin; and wherein the other of said first and second polymer compositions is substantially free of polyolefin when containing polyvinylidene fluoride.