| 摘要 |
In a heating element comprising an electrical resistance layer disposed between two areal electrodes extending generally parallel to one another, the resistance layer is formed to be thermally insulating and is permeated with electrically conductive plastics material having a positive temperature coefficient of electrical resistance. The conductive plastics may comprise thermoplastics material incorporating a particulate filler of granular, spheroidal or bubble form, and the electrodes may be coated black to serve as black bodies. The element may be disposed within a thermally insulating member acting as a heat shield. |
