What Factors Affect The Tightness Of The Stretch Wound Film

It is necessary to know that the winding film is a product for the packaging industry, which has a very good use effect, but the use effect of the product has a very close relationship with its tightness. So what factors will affect the tightness of the membrane?
1, polyester (PET, PBT, PEN, PETG) is a polar polymer, its surface free energy is high, surface wet tension in 40 dyne/cm or more. However, for high-speed color printing or to increase the bonding force between vacuum aluminized layer and BOPET film surface, surface treatment of BOPET film is also needed to further improve its surface wet tension.
2, non-polar polymer, winding film surface free energy is small, surface wet tension is low, generally about 30 dyne/cm. In theory, if the surface tension of the object is less than 33 dynes/cm, ordinary ink or adhesive can not be attached firmly, so it must be treated on the surface;
3. Aluminum plating layer transfer occurs when aluminum plating, and glue coating layer transfer occurs when gluing. The main measure to prevent the corona on the reverse side of the winding film is to adjust the pressure of the rubber compaction roll before the corona treatment roll, and the pressure at both ends of the compaction roll should be consistent and the pressure size should be appropriate.
In fact, in the process of producing wound film, there will be a problem of too loose tightness, we can know through the answer of professionals, the tightness of the wound film surface will depend on the molecular structure of the film material itself, and the size of the free energy of the wound film surface determines whether the wound film has a good tightness. Therefore, the performance of all aspects of the winding film is related to each other, so no matter during the production of the winding film or when it is used, it is necessary to carry out relevant operations in accordance with the regulations, and more precautions should also be understood.
Therefore, through the above content, it can be seen that the tightness of the winding film is mainly affected by the above factors, so whether it is the purchase of the product or the use of the product, we should pay more attention to this aspect.