Stretch film, also known as tensile film, heat shrinkable film, the earliest to PVC as the substrate, DOA as a plasticizer and from the production of self-adhesive PVC Chan Raomo. Dongguan stretch film supply due to environmental problems, high cost (relative to the PE than the major, the unit packaging area less), poor tensile and other reasons, when the 1994-1995 domestic production of PE stretch film gradually eliminated. PE stretch film first to EVA for the self-adhesive material, but its high cost and taste, after the development of PIB, VLDPE for the self-adhesive material, the substrate is now mainly LLDPE, including C4, C6, C8 and metallocene PE (MPE).

Early LLDPE stretch film to blown film for more, from the single layer to the development of two, three; Dongguan Chanrao film supply LLDPE stretch film production is now the main casting, the process shown below, this is because the casting Line production with uniform thickness, high transparency, etc., can be applied to high-rate pre-stretch requirements. As the single-layer casting can not do single-sided adhesive, the application area is limited. Single, double-cast in the choice of materials on the three-tier cast without the wide, high cost of the formula, it is still a three-tier coextrusion structure is ideal. High-quality stretch film should have the characteristics of high transparency, high longitudinal elongation, high yield point, high transverse tear strength and good puncture performance.