Machine-grade stretch film is primarily manufactured using polyethylene material through a process involving melt extrusion, cast molding, cooling and setting, stretching, and winding. Because machine-grade stretch film must withstand the high-speed operation of automated packaging equipment, strict control over thickness, tensile properties, and self-adhesion is essential during production to ensure consistent packaging performance.
During the raw material preparation stage, manufacturers typically select linear low-density polyethylene (LLDPE) as the primary material, incorporating additives such as tackifiers and antistatic agents based on specific performance requirements. After batching and thorough mixing, the raw materials enter the extrusion equipment, where they undergo melting and plasticization at high temperatures to achieve a uniform, stable molten state.
The molten plastic is extruded through the machine and a precision die to form a continuous film. Some high-performance machine-grade stretch films utilize multi-layer co-extrusion technology; by combining different material layers, the film achieves a balance of high strength, good toughness, and stable adhesion. The formed film is rapidly cooled using cooling rollers to stabilize its structure and enhance surface smoothness.
The film undergoes drawing and stretching, thickness inspection, and winding to form a master roll, which is subsequently slit and packaged according to customer specifications. Throughout production, parameters such as thickness, transparency, tensile strength, self-adhesion, and visual quality are monitored to ensure the product meets operational requirements. Through optimized production processes and equipment control, high-performance machine-grade stretch films suitable for automated packaging equipment can be produced.