To meet the specific functional requirements of plastic film packaging materials during production, multi-layer co-extrusion blown film machines have been developed by blowing and co-extruding multiple materials with different properties (such as breathability, waterproofness, heat insulation, and toughness) together to form multifunctional plastic films. The purpose of multi-layer co-extrusion blown film machines is to leverage the advantages of multiple materials and avoid the disadvantages of single-material or single-layer blown film machines.
For example, PP and PE co-extrusion blown film machines combine the high hardness of PP with the high gloss of PE to produce films that combine these two properties.
Multi-layer co-extrusion blown film machines are further categorized into several types, such as two-layer, three-layer, five-layer, and seven-layer co-extrusion blown film machines. Three-layer co-extrusion blown film production lines utilize advanced technologies such as new high-efficiency, low-energy-consumption extruders, IBC internal cooling systems, ±360° horizontal upper traction rotation systems, photoelectric automatic correction devices, fully automatic winding and film tension control, and computer-controlled automatic control systems. Compared with similar equipment, this equipment boasts advantages such as higher output, better plasticization of products, lower energy consumption, and simpler operation. It completely solves problems like film edge curling and uneven winding, elevating product quality to a new level. The produced film exhibits high transparency, puncture resistance, high toughness, excellent low-temperature heat-sealing properties, good composite strength, and anti-curling properties. Due to its excellent barrier properties, it offers freshness preservation, moisture protection, frost protection, oxygen barrier, and oil resistance, making it widely applicable for both light and heavy-duty packaging. Applications include various fresh fruits, meat products, pickles, fresh milk, liquid beverages, and pharmaceuticals.
Five-Layer Co-Extrusion: The five-layer co-extrusion blown film unit is primarily suitable for resins with gas barrier properties such as HDPE, MHDPE, LDPE, LLDPE, MLLDPE, PA, and EVOH. The produced films are mainly used for heavy-duty packaging, high-end food bags, vacuum packaging bags, and liquid packaging bags, achieving the packaging objectives of aroma preservation, freshness preservation, corrosion prevention, airtightness, and extended shelf life.
