Wrap-around film is a packaging method in which items are tightly wrapped for transport and storage using a mechanical stretching device or by hand at room temperature with strong stretching of the film. It is a very popular method of packaging worldwide. It uses imported resins and advanced flow film extrusion production technology.
It has good stretchability, permeability, tear resistance, good self-adhesiveness, high shrinkage, strong resistance to permeation, tight packaging, high transparency and no loosening. Stretch wrap film can be widely used for foodstuffs, fertilizers, electromechanical products, chemical raw materials, light textile products, etc. Single-piece or pallet packaging, including other bundled packaging.
Wrapping film must be stretched. The mechanical packaging of pallets can be stretched in the following ways: direct stretching, and pre-stretching. There are also two types of pre-stretching: one is roll pre-stretching and the other is electric stretching.
It is designed to complete the stretching between the pallet, and the stretch film. This method has a relatively low stretch ratio (about 15 to 20 %). If anything, the stretch ratio can exceed 55% to 60%. This exceeds the original yield point of the stretch wrap and the width of the stretch wrap is reduced. The puncture properties are also lost and the film is more likely to break. Also, at 60% stretch rate, the tension is still very high and for lighter goods it is likely to deform the product.
The stretching mechanism of electric pre-stretching is the same as that of roll pre-stretching. The difference is that the two rolls are driven by electricity. And the stretching is completely independent of the rotation of the pallet. Therefore, it is more adaptable. It is suitable for light, heavy and irregular items. Due to the low tension during the packaging process, the method achieves pre-stretching rates of up to 300%, resulting in significant material savings and cost reductions. Suitable for film thicknesses of 15 to 24 μm.
In summary, stretch film has a wide range of applications, many of which have not yet been covered domestically, and many of the areas covered are not yet widely used. With the expansion of application areas, the number of stretch films will increase greatly. , its market potential is incalculable. Therefore, it is necessary to vigorously promote the production and application of stretch film.