| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a vacuum heat insulating material which keeps heat insulating effect for a long period of time. <P>SOLUTION: This vacuum heat insulating material 1 comprises gas barrier covering materials 7 having thermal welding layers, and a plurality of plate-shaped core materials 6c, 6d, and the core materials 6c, 6d are decompressed and sealed between the covering materials 7 of which the thermal welding layers are faced to each other, in a state of being positioned in spaces independent from each other. As an area of a part of the core material 6c close to at least an end portion of the covering material 7 is smaller than an area of the other core material 6d, the air and moisture vapor intruding from the end portion of the covering material 7, intrude into the independent space including the core material 6c close to the end portion of the covering material 7, the vacuum in the independent space including the core material 6c is gradually lowered, and heat insulating effect is deteriorated. However, as the area occupied by the core material 6c, of the whole vacuum heat insulating material 1 is smaller than an area occupied by the other core material 6d, of the whole vacuum heat insulating material 1, the influence to the heat insulating effect of the whole vacuum heat insulating material 1 is reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
