How to distinguish between wound film and stretch film
Stretch film is also called stretch film, heat shrink film, the earliest to PVC as the substrate, DOA plasticizer and self-adhesive effect from the production of PVC stretch film. But the cost is high, PE stretch film first EVA as self-adhesive material, but also taste, after the development of PIBV, LDPE as self-adhesive material, the substrate is now mainly LLDPE, including C4, C6, C8 and metal PEMPE. From the single layer to the development of two, three; now to produce LLDPE stretch film casting method, early LLDPE stretch film to blow film as much. This is because the cast line production with uniform thickness, high transparency, etc., can be applied to high rate pre-stretching requirements. As a single layer of casting can not do single-sided sticky, application areas are limited. Single, double cast in the choice of information on the three layers of cast a wide, recipe interest is high, so it is still three layers of co-extruded 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.