| 摘要 |
1,144,846. Electric heating resistors. TEXAS INSTRUMENTS Inc. 16 Aug., 1967 [5 Oct., 1966], No. 37726/67. Heading H5H. [Also in Division H1] A polygonal resistance heating tile comprises a layer 26 of conductive polymeric material sandwiched between insulating polymeric layers 23, 25, a firm bond between the layers being achieved by a cross-linking operation. The latter may involve heating, compressing, ionizing radiation or the use of cross-linking agents. The polymeric material may be a polyolefin, halogenated polyolefin, polyacrylic resin or polyester, loaded with powdered metal or carbon to make it conductive. The conductive layer may alternatively be a polymer with ionic sidechain substituents. The conductive part of the tile need not extend over the whole tile area, but extends from one side to the opposite or an adjacent side (Figs. 7, 8, not shown). Conductive epoxy resin may be used to connect adjacent conductors. The conductors are stated to show non-linear positive temperature coefficient of resistance, affording some selfprotection to the heating circuit. |
