Analysis Of The Causes Affecting The Shrinkage And Tightness Of Hand Wrapping Film

1. Reasons affecting the shrinkage performance of hand wrapping film:

1. Aluminum plating occurs during the aluminum plating process, and the coating moves during the gluing process. The main measure to prevent corona on the back of the stretched film is to adjust the pressure of the rubber extrusion roller in front of the corona treatment roller. The pressure on both ends of the squeeze roller must be consistent and the pressure should be appropriate.

2. Polyester is a polar polymer with high surface free energy and surface wetting tension greater than 40 dynes/cm. However, for high-speed color printing, or in order to increase the bonding force between the vacuum aluminized layer and the surface of the stretched film, the surface treatment of the stretched film needs to further increase the surface wet tension.

3. Non-polar polymers have small surface free energy and low surface wetting tension, usually about 30 dynes/cm. Theoretically, if the surface tension of the object is less than 33 dynes/cm, ordinary inks or adhesives cannot adhere firmly, and the surface must be treated.