The production process of vacuum bags varies due to different materials, uses and performance requirements, which are mainly reflected in material selection, manufacturing process and packaging methods. The following are the differences in the production process of different types of vacuum bags:
1. Different material selection
The material of the vacuum bag determines its performance. Common materials include:
PA+PE (nylon+polyethylene): good flexibility, strong puncture resistance, often used in food packaging.
PET+PE: high transparency, high temperature resistance, can be used for frozen food or heated food.
Aluminum foil+PE: strong shielding, light and moisture proof, suitable for light-proof foods such as tea and coffee.
EVOH co-extruded film: high barrier properties, suitable for long-term fresh-keeping packaging of meat products, cooked food, etc.
2. Different production processes
The production of vacuum bags usually involves the following processes:
(1) Blow molding process
Applicable to co-extruded film vacuum bags such as PA/PE and EVOH.
Multi-layer plastic materials are co-extruded through blow molding equipment to ensure high barrier properties.
(2) Casting process (CAST)
Applicable to vacuum bags made of materials such as PET/PE.
The plastic is melted and extruded by a casting machine, and then formed by a cooling roller to improve transparency and flatness.
(3) Dry lamination process
Applicable to multi-layer composite vacuum bags such as PET/AL/PE.
By applying glue, different materials are compounded together to form high-barrier, multifunctional vacuum packaging bags.
(4) Solvent-free lamination process
Environmentally friendly process, avoiding solvent residue, suitable for food-grade vacuum bag production.
Through a solvent-free lamination machine, each layer of material is hot-pressed and bonded to ensure that the bag body is firm.
3. Different packaging processes
Heat-sealing edge process: high-temperature sealing is used to ensure that the seal is firm and not easy to leak.
Three-Side-Seal: Applicable to food packaging such as meat and seafood.
Stand-Up Pouch: Used for liquid or granular food, can be used with a zipper seal.
Aluminum foil vacuum bag: High-temperature packaging is used to ensure that the contents are not affected by light and oxygen.
The production process of vacuum bags varies depending on the material, purpose, and performance requirements. The common differences are the choice of co-extrusion and composite processes, as well as the final packaging method. Different types of vacuum bags are suitable for many industries such as food, electronics, and medicine, and each has its own advantages and disadvantages in terms of high temperature resistance, oxygen barrier, moisture resistance, and transparency.
