| 摘要 |
PROBLEM TO BE SOLVED: To obtain a large, strong, and highly functional airtight bag used as a cushioning medium, lord-movement prevention medium, or the like when a large quantity of goods are transported. SOLUTION: In an airtight bag constituted by opposing bag walls, each comprising porous cloth such as nonwoven fabric and a heat-weldable plastic film superimposed together, join lines, which are, for example, a peripheral join line 5 of the porous cloth 3 and heat-weldable plastic film 4 and a section line 6, and annular join lines, which surround parts where strength-deficiency easily occurs among the intersections of the join lines 5 and 6 and terminal points, are formed so that the layer of porous cloth 3 is buried in the layer of heat-weldable plastic film 4 and the heat-weldable plastic films 4 are welded together, thereby sectioning by the heat join and constituting air chambers having each function. |
