| 摘要 |
PROBLEM TO BE SOLVED: To provide a material having improved heat-resistance, not changing in its electrical resistance value over a long period of time, and having high flexibility, by using a condensed polycyclic polynuclear aromatic resin prepreg as a material for covering the heating element. SOLUTION: A heating surface is formed by impregnating or printing a sheet-like base material with a conductive material such as graft carbon. Electrode parts are provided on both end parts of a longer side thereof to form a heating element. The heating element is covered with a condensed polycyclic polynuclear aromatic resin prepreg. Or further, an insulation coating is formed by layering thereon a resin film of at least one kind selected from among polyimide, polyether imide, polysulfone, and polyphenylene sulfide. It is preferable to use, as the condensed polycyclic polynuclear aromatic resin, a resin synthesized by a dehydration/condensation reaction of a hydroxymethyl compound with a mixture of naphtalene, anthracene, phenanthrene, pyrene, etc., and phenol, resorcinol, etc. |
