The common bag types of food packaging bags are as follows: 1.three side seal bagThree-side seal bags have two side seams and a top seam bag whose bottom edge is formed by folding the film horizontally. The bags are available with or without the hem, and when they do, they stand upright on the shelf.A deformation of the three-side sealing bag is to fold the bottom edge formed by the original edge, and realize it by bonding, so that it becomes a four-side sealing bag in essence. 2.back seal bagBack-sealing bags are also called pillow-shaped 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-shaped bags. The back seam of the pillow bag forms a fin-like envelope in which the film inner layers are brought together to seal and the seam protrudes from the back of the sealed bag. Another form of sealing is overlapping sealing, where the inner layer on one side is bonded to the outer layer on the other side to form a flat seal. because”fin”The shape seal is relatively strong, and as long as the inner layer of the packaging material is heat-sealed, it is widely used. and”overlapping”The shape seal is relatively weak, and the inner and outer layers of the bag are required to be heat-sealing materials, so not many are used.The top seal and bottom seal are bonded together by the inner material of the bag. 3.gusset bagGusset bag is also called fold bag, organ bag, which is the deformation of the back seal bag, which is formed by folding the two sides of the bag.mtype. ifmAsymmetric shape, also known as trapezoidal hem bag.4.four side seal bagFour side seal bags are usually made of top, side and bottom edge seals of two (roll) materials, compared to the previously mentioned bags, it is possible to use two different plastic resin materials if they can be bonded to each other If so, make a four-side sealed bag with the front side glued. Four side seal bags can be made in various shapes such as hearts or ovals. 5.zipper bagPouch with easy-open zipper on three-side seal pocket and main pocket. 6.Three-dimensional bagThere are many types of three-dimensional bags, mainly the following types:①Bottom boat-shaped stand-up bag.②Folding bottom integrated three-dimensional bag.③Inclined knife heat-sealed three-dimensional pouch.④Bottle-shaped knife mold three-dimensional bag.⑤The three-dimensional bag with mouth is divided into three-dimensional bag with oblique mouth and three-dimensional bag with roof cover.⑥Air pressure stand up bag. 7.Shaped bagVarious bag shapes such as fruit shape and cartoon shape. 8.With hand hole bagHole shapes include triangle, butterfly, airplane, round, semicircle, waist drum, etc.