Back Sealing Bag Of Food Packaging Bag

Back seal bags are also called pillow bags. The bags have back, upper and lower seams, making them have the shape of a pillow. Many small food bags are often packaged in pillow bags. The back seam of the pillow bag forms a fin-like envelope in which the inner layers of film are brought together to seal, with the seam protruding from the back of the enclosed bag. Another form of sealing is overlapping sealing, in which the inner layer on one side is bonded to the outer layer on the other side to form a flat seal. Because the "fin" shape seal is relatively strong, and as long as the inner layer of the packaging material is heat sealed, it is widely used. The "overlapping" shape seal is relatively weak, and requires the inner and outer layers of the bag to be heat-sealed, so it is not used much.

The top and bottom seals are bonded to the bag inner material.