| 摘要 |
PURPOSE: To enhance sealing performance, durability and chemical resistance by reducing or preventing the peeling of each aluminum foil at a seal jointing part around the circumferential peripheral part of each laminated sheet when a planar heating element is hermetically sealed by the use of each laminated sheet which has a plastic film jointed with an aluminum foil. CONSTITUTION: A planar heating element 10 is hermetically sealed by each laminated sheet 13 which has a plastic film 14 joined with an aluminum foil 15. In this case, areas B and D with plastic film 14 only is provided for the circumferential peripheral parts of two laminated sheets 13 and 13 at both sides, and heating and thermal depositing are performed for the inside of each plastic film only area or an area laid across the junction of each aluminum foil 15 with each plastic film 14. |
