The difference between stretch film and wound film

 

The difference between stretch film and wound film

Stretch film is mainly used for product packaging. For some companies, using stretch film to package products can effectively reduce the cost of use, while reducing labor intensity of workers, improving packaging efficiency and packaging grades. So what is the difference between stretch film and stretch film? Today, Zhiteng stretch film manufacturer will introduce to you.

Stretch film, also called stretch film and heat shrink film, was originally produced with PVC as base material, DOA as plasticizer and self-adhesive effect. Due to environmental protection issues, high cost (relatively high relative to PE, less unit packaging area), poor stretchability, etc., when the production of PE stretch film began in 1994-1995, it was gradually eliminated. The PE stretch film first uses EVA as the self-adhesive material, but its cost is high, and it has a pungent odor, and then it is developed to use PIB and VLDPE as the self-adhesive material, and the base material is mainly LLDPE, including C4, C6, C8 and Mao Metal PE (MPE).

Stretched films have developed from single-layer to two-layer and three-layer. Nowadays, LLDPE stretched films are mainly produced by casting method. In the early days, LLDPE stretched films were mostly blown films.
This is because the casting line has the advantages of uniform thickness and high transparency, which can be applied to the requirements of high-magnification pre-stretching. Because single-layer casting cannot achieve single-sided adhesion, the application field is limited. Single-layer and double-layer casting are not as wide as three-layer casting in terms of material selection, and the formula interest is also high, so the three-layer co-extrusion structure is more ideal.
A 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.

Therefore, it can be seen that stretch film and stretch film belong to the same thing by looking at the appearance, but the concept of stretch film is broader. Stretch film is also called stretch film, thermal stretch film, and some stretch film. Stretchable, some stretch films are not stretchable, or the stretch rate is low, so stretch films belong to the category of stretch films.