Stretch film, also called stretch film and heat shrink film, is the first domestic PVC stretch film to be produced with PVC as the base material and DOA as the plasticizer and self-adhesive. Due to environmental protection issues, high cost (relative to PE’s high proportion, less unit packaging area), poor stretchability, etc., it was gradually eliminated when the domestic production of PE stretch film was started from 1994 to 1995. The PE stretch film first used EVA as the self-adhesive material, but its cost was high and it had a taste. Later, PIB and VLDPE were used as self-adhesive materials, and the base material was mainly LLDPE, including C4, C6, C8 and metallocene PE ( MPE).
1. Sealed packaging
This kind of packaging is similar to shrink film packaging. The film wraps the tray around the tray, and then two thermal grippers heat seal the film at both ends. This is the earliest use form of stretch film, and more packaging forms have been developed from this
2. Full width packaging
This kind of packaging requires the film to be wide enough to cover the pallet, and the shape of the pallet is regular, so it has its own, suitable for film thickness of 17～35μm.
3. Manual packaging
This kind of packaging is the simplest kind of stretch film packaging. The film is mounted on a rack or hand-held, rotated by the tray or the film revolves around the tray. It is mainly used for repackaging after the wrapped pallet is damaged, and ordinary pallet packaging. This kind of packaging speed is slow, and the suitable film thickness is 15-20μm;
4. Stretch film wrapping machine packaging
This is the most common and extensive form of mechanical packaging. The tray rotates or the film rotates around the tray. The film is fixed on a bracket and can move up and down. This kind of packaging capacity is very large, about 15-18 trays per hour. The suitable film thickness is about 15～25μm;
5. Horizontal mechanical packaging
Different from other packaging, the film is revolved around the article, which is suitable for long goods packaging, such as carpets, boards, fiberboards, special-shaped materials, etc.;
6. Packaging of paper tubes
This is one of the latest uses of stretch film, which is better than the old-fashioned paper tube packaging. The suitable film thickness is 30～120μm;
7. Packing of small items
This is the latest packaging form of stretch film, which can not only reduce material consumption, but also reduce the storage space of pallets. In foreign countries, this kind of packaging was first introduced in 1984. Only one year later, many such packaging appeared on the market. This packaging form has great potential. Suitable for film thickness of 15～30μm;
8. Packaging of tubes and cables
This is an example of the application of stretch film in a special field. The packaging equipment is installed at the end of the production line. The fully automatic stretch film can not only replace the tape to bind the material, but also play a protective role. The applicable thickness is 15-30μm.
9. Stretching form of pallet mechanism packaging
The packaging of stretch film must be stretched, and the stretching forms of pallet mechanical packaging include direct stretching and pre-stretching. There are two types of pre-stretching, one is roll pre-stretching and the other is electric stretching.
Post time: Jun-02-2021