PTC composition and resistive device and LED illumination apparatus using the same
US9177702B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2013 |
| Grant date | Nov 3, 2015 |
| Priority date | — |
| Expiry date | Mar 3, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01C17/06566
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A PTC composition comprises crystalline polymer and conductive ceramic filler dispersed therein. The crystalline polymer has a melting point less than 90° C. and comprises 5%-30% by weight of the PTC composition. The crystalline polymer comprises ethylene, vinyl copolymer or the mixture thereof. The vinyl copolymer comprises at least one of the functional group selected from the group consisting of ester, ether, organic acid, anhydride, imide or amide. The conductive ceramic filler comprises a resistivity less than 500 μΩ-cm and comprises 70%-95% by weight of the PTC composition. The PTC composition has a resistivity about 0.01-5 Ω-cm and its resistance at 85° C. is about 103 to 108 times that at 25° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.