Self limiting microwave heaters
US5410135A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1993 |
| Grant date | Apr 25, 1995 |
| Priority date | — |
| Expiry date | May 21, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D2581/3494
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A self-limiting dispersion of a conductive material in a binder is disclosed wherein the conductive material consists essentially of a carbon material having a structure selected to undergo percolation when dispersed in the binder at a concentration of from about 10 weight percent to about 45 weight percent. The binder comprises a thermoplastic material selected to go through a first order phase transition or a second order transition at a temperature from about 300.degree. F. to about 480.degree. F. and the dispersion is formulated near the conductance percolation threshold so that its electrical conductivity drops precipitously (e.g., at least about 1.5 orders of magnitude) above the binder transition temperature. The dispersion of the conductive material in the binder is especially suitable for use as a self-limiting microwave heater material which is either a molding composition, or surface coating composition, and especially a composition that can be applied to a substrate by printing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.