As a kind of packaging bag, the vacuum bag mainly plays the role of resisting pressure, blocking the air, and maintaining the original properties of the product, in addition to the trditional functions of the normal packaging. The vacuum bag can more effectively keep the original color, aroma, taste, shape and nutritional value of the food for a long time.
Here I will introduce several material structures of the vacuum pouch;
1. material:ALUMINIUM
Usually the material structure should be PET/AL/CPE or PET/NY/AL/CPE,Among them,PET is with good properity of printing,NY is with good resistance of the oxygen,AL is with good barrier,opaque,CPE is used as the inner sealing layer.This product has good anti-static, oxygen-barrier, shielding, moisture-proof, light-shielding functions and excellent heat sealability. Aluminum foil vacuum pouches are widely used in food, electronics, chemical and other industries. Because aluminum foil itself is expensive, the cost of aluminium vacuum pouch will be higher.
2. Material: Nylon Process: Co-extrusion
The nylon co-extruded pouch is composed of PA, EVOH and resins such as PE, PP, and TIE, combined with a symmetrical or asymmetrical structure. The addition of PA and EVOH greatly improves the barrier properties of oxygen and fragrance, laminated peel strength, environmental resistance, and shelf life of the products. Nylon co-extrusion pouch is a multi-layer co-extrusion high-barrier packaging material, which is the world’s most advanced food packaging material. Extrusion is a green and environmentally friendly production method for packaging.7-layer co-extrued film is produced by the 7 different nozzels with resins such as PA, PE, PP, TIE, EVOH, etc.,and merges them in a die through their respective flow channels, and then blows them together ,cool and compound.. Co-extruded high-barrier packaging material has the characteristics of no pollution, high barrier, strong function, low cost, small capacity ratio, high strength, flexible structure, etc. It makes the production process of food packaging pollution-free.
3. Material: Nylon Process: Laminated Representation: Three-side seal
The material used for laminated nylon pouch is similar to that of nylon co-extrued. PET / PE, PVC / PE, NY / PVDC, PE / PVDC, PP / PVDC are mainly different during the produced process. Laminated pouches are generally composed of a substrate, glue, barrier materials, heat sealing materials, printing and protective coatings. The commonly used laminated film structure is: surface layer / adhesive layer 1 / intermediate barrier layer / inner layer heat-sealing layer.Nylon lamination is compounded layer by layer through a laminator, and glue needs to be added in the middle. Only because of this, the biggest disadvantage of nylon lamination is that when the weather is dry, especially in winter, the pouch breaking rate will be much higher.
4.Material: PE
PE pouch is the most widely used plastic film in the market, which is cheap. But PE film has great air permeability and sealing strength is weak, if it is used as a vacuum bag, the breakage rate is high.