Since the spring festival holiday, the raw materials for stretch films have been on the rise, until the price of the stretch film reached a very high stage in March, some clients will ask: “Why is the recent price of the stretch film so expensive?” Sinyar Packing Film wants to ask: “Do you really know the true stretch film production process?”
Some of the key indicators of the stretch films, such as tensile, transparency, viscosity and what is to decide, understand these, you know why some of the stretch films are so expensive, so good quality. We choose stretch films not because of their low price, but to compare the unit cost, today, Wuxi Sinyar brings you a deeper understanding of stretch films.
| First of all, let’s look at the composition of the stretch films. Unlike food grade wrap film, the wrap film on the market is generally made from raw materials such as LLDPE and metallocene compounds, the quality of the stretch film is determined by the number of metallocene compounds added. The metallocene compounds have good processability, high strength, good rigidity and transparency, and are very good in heat resistance and chemical resistance, the addition of metallocene compounds to a certain extent can greatly improve the performance of the stretch film, which will also increase the cost.
| Let’s look at the production process of stretch film. The current stretch film generally adopts multi-layer co-extrusion technology. By adjusting the mixture ratio of various compounds and adding some special substances, it can achieve single-sided or double-sided viscosity, colorless and tasteless, retraction and other characteristics.
| Another way to make the film sticky is to add glue particles to the film during the production of the stretch film. However, the disadvantage of this method is that the film is stretched twice or three times, glue particle viscosity will be greatly reduced, after winding easy to produce tail film off phenomenon, and this film thickness will generally be larger, feel not smooth, there is a clear sense of particles.
You must pay attention to the choice of stretch film, is not the thicker the film, film’s tensile and resistance to penetration are better, the thicker the film, meaning that the length of each kilogram is shorter. Thin film and thick film have different applicability, for cartons of goods, thin stretch film can play a good wrapping, and for stacking irregular, heavy, easy-to-disperse goods, choosing a bit thick stretch film will be better.
