Causes of crystal points in PE protective film
Jan 06, 2022
Analysis and explanation of the problem of crystal point of PE protective film
In daily life, PE protective film is relatively common in the protective film market, and it is used in many fields, especially in the protection of products in the process of production, processing, transportation, etc., so that the product will not be Contaminated, corroded and scratched. Then in the process of use, sometimes it is found that there are crystal points on the PE protective film.
Crystal dots, also called fish eyes, are shaped like small and hard bead dots, which affect the appearance of the film and will form bumps after being compounded with other substrates. Even the first-grade resin raw materials will produce crystal points, and excessive heating during the production process or the retention of molten raw materials will cause crystal points. In the production process, poor quality raw material particles or high molecular weight (crosslinked) will form crystal points. The appearance of crystal points is very similar to the appearance of water vapor bubbles or unmelted resin.
1. The main reasons for the occurrence of crystal points of pe protective film are as follows:
1. The cleanliness of raw materials, including the cleanliness of the raw materials themselves, and the dust pollution of the environment; therefore, pay attention to the production process of PE protective film.
2. In terms of raw material selection, the melting quality of several raw materials is quite different and the compatibility of raw materials is easy to appear; therefore, the selection of raw materials is very important.
3. In terms of processing conditions, improper processing temperature will cause poor plasticization or over-plasticization of raw materials, which will cause crystal points.
4. The processing capacity of the equipment, equipment barrel screw, filter, etc. also have a very important influence on the generation of crystal points.
