| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a bag body of high sealing property maintaining excellent vacuum performance over a long period of time. <P>SOLUTION: The bag body has a side 31 formed by bending in half a sheet of envelope material having a heat welded layer on one side and heat-welding at least one side of sides connected to the bent part, and the remaining sides 34B, 34C serving as an opening for putting in a filler 2. When looking at a cross section in the case of cutting the heat welded part at a plane perpendicular to at least the partially heat welded side 31 of the mutual heat welded side 31 of the outer peripheral parts of the envelope material, one of the heat welded layers of the envelope material located at the heat-welded side 31 has at least two recesses, and the heat welded layer of a deepest part of the recess is provided with a seal groove 33 formed of a thin-walled part thinner than the thickness of the average heat welded layer, and thick-walled parts located at both ends of the thin-wall part and thicker than the thickness of the average heat-welded layer. The seal grooves 33 are formed on the remaining sides 34B, 34C serving as the opening for insertion. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
