| 摘要 |
PURPOSE: To thin the periphery of an electrode wire, and easily install the electrode wire on a heating resistance sheet by forming a heating composition of a covered wire rod to be fused on the heating resistance sheet as a composition to show an electric resistance value equal to or lower than the heating composition of the heating resistance sheet. CONSTITUTION: A material which has respectively thermoplastic resin and conductive particles and has a positive temperature coefficient characteristic by which an electric resistance value increases together with a temperature rise, is used as a heating resistance sheet 2 of a sheet-like heating element 1 and a heating composition of covered conductors 4. Co-extrusion molding is performed on the sheet 2 and an electrode wire group 3 in which plural pieces are arranged in a plate shape in parallel to each other without crossing solid wires 3A of electrode conductors with each other, and the heating element 1 is constituted. Due to this constitution, a heating sheet is properly heated, and is not heated by a covered wire rod. |
