Reclosable bag

摘要

The reclosable bag has a gusset side structure so that the bag can be self-supporting on its bottom surface. The reclosable structure can be an internal structure or an external structure. As an external structure the front and rear walls extend above the reclosable seal and are bonded together above the reclosable seal. This extended wall structure is removed to remove these tamper evident seal. If within the bag the tamper evident seal is composed of a loop of film extending downward from each side of the reclosable seal to seal the contents of the bag. This loop must be broken to open the bag. The preferred reclosable seal is a zipper with bonded stays or each end to maintain the zipper on the bag. The bag has diagonal seals at the lower corners for forming a flat bottom to the bag and at the upper corners to provide vents for pressure equalization. The bags are made by a process where all processing is on line except for forming the zipper which is constructed off-line. The zipper is added in the machine direction and the gusset sidewalls in the cross-direction. At the end of the bag making line they are severed and printed. The bags can be immediately filled.