Many people know food packaging bags, but they don’t know much about the bag types of food packaging bags. So what are the types of food packaging bags? Next, I will introduce the bag shape of several common composite food packaging bags.

1. The three-side sealed bag has two side seams and a top seam bag, and its bottom edge is formed by horizontally folded film. The bags can be folded or not. When there are white edges, they can stand upright on the shelf. A kind of deformation of the three-side sealing bag is to fold the original side to form the bottom edge and realize it by bonding. In this way, it essentially becomes a four-side sealing bag.

2. Back-seal bags are also called pillow-shaped bags. The bags have back, top and bottom seams, making them have a pillow-like shape. Many small food bags are often packed in pillow-shaped bags. The back seam of the pillow-shaped bag forms a fin shape. In this structure, the inner layers of the film are put together and sealed, and the seam protrudes from the back of the sealed bag. Another form of sealing is overlap sealing, in which the inner layer on one side is bonded with the outer layer on the other side to form a flat seal. Because the "fin"-shaped seal is relatively strong, and as long as the inner layer of the packaging material is heat-sealed, it is widely used. The "overlapping" seal is relatively weak, and requires the inner and outer layers of the bag to be made of heat-sealing material, so it is not used too much. The top seal and the bottom seal are bonded by the inner material of the bag.

3. Folding bags are also called fold-over bags or organ bags. They are the deformation of back-seal bags. Both sides of the bag are folded in to form an M shape. If the M-shape is asymmetrical, it is also called a trapezoidal hem bag.

4. Four-side sealing bags are usually made by sealing the top, sides and bottom of two materials. Compared with the bags mentioned before, it is possible to use two different plastic resin materials. If they can be mutually For bonding, make a four-sided sealed bag with the front side bonded. The four-side sealing bag can be made into various shapes, such as heart shape or oval shape.

5. The zipper bag is equipped with an easy-open zipper bag on the three-side sealing bag and the main body bag.