Introduction to three different materials for heat shrink packaging films: POF, PE, and PVC
1. PE: This film is primarily used for wrapping heavy objects, such as optical cables, pipes, and even whole bottles of cola. It mostly comes in tubes. Inspection standards include transparency, purity, and film uniformity.
2. POF: This shrink film is formed by compression molding and usually comes in bags. If using tubes, the order quantity needs to be several tons or more. Standard color: Transparent. Printing can be customized. Products are mainly used for packaging pharmaceuticals, cosmetics, and sterilized tableware. Inspection standards: Does it open during shrinking? Does the print fade? Transparency.
3. PVC: This shrink film is blow-molded and usually comes in rolls (it can also be made into bags or cut into individual tubes according to customer needs). Common colors are sapphire blue and light green. Thickness is usually 5 mils. PVC film is currently the most widely used film material. It is inexpensive, has a large temperature range, and requires little heat source; the primary heat source for processing is hot air, infrared radiation, or a combination of both. However, PVC is difficult to recycle, produces toxic gases when burned, and is environmentally unfriendly, leading to its ban in Europe and Japan. Inspection primarily involves checking: transparency, gloss, the presence of nodules in the film, and film uniformity.