| 摘要 |
<p>PURPOSE:To reduce cost by a large margin and improve reliability by forming film structure with gas barrier performance and heat resistance imparted to an outer cover material container. CONSTITUTION:An outer cover material container 12 is formed by thermoforming a laminated sheet formed of a plastic film protecting layer 13, a metallic foil layer 14 and a plastic gas barrier layer 15 heat-weldable with gas barrier performance. The whole periphery of an intermediate cover 16 formed of unwoven fabric is heat- welded to the whole opening part surface of the outer cover material container 12, and after filling silica serving as core material 17 into a space surrounded by the outer cover material container 12 and the inter mediate cover 16, the container 12 is put in a drying furnace of 100 deg.C or higher to remove water content in the core material 17. The container 12 is then taken out of the drying furnace, and an outer cover material cover 18 formed of multilayer laminated film with aluminum vapor- deposited layer is set. After heat-welding three outer sides, the container 12 is put in the vacuum chamber, and evacuated from one non-heat-welded side. Upon reaching the specified degree of vacuum, one side is heat-welded to hold the inside of the container airtightly to form vacuum heat insulating material 11. An inner container can be thereby eliminated.</p> |
