There are many types of TPU films on the market. How do we choose good TPU films?
Due to the different colors of the substrates, the color requirements of the hot melt film should be different. If there is no special requirement for the color of the substrate itself, it is recommended to use a yellow hot melt film. Generally, the yellow hot melt film is more viscous and more elastic than white.
2. The surface treatment of the substrate
The surface of the hot melt adhesive film is not as strict as the other adhesives, but the dust and oil on the surface of the adhesive should be properly treated to make the hot melt adhesive film better.
3. Working time
Fast work is a major feature of hot melt adhesive film. The working time of hot melt adhesive film is generally about 15 seconds. With the wide application of modern production methods--pipeline, the working time requirement for hot melt adhesive film is shorter and shorter, such as bookbinding and speaker manufacturing for hot melt adhesive film. The working time is required to reach about 5 seconds.
4. Temperature resistance
Hot melt adhesive film is sensitive to temperature. When the temperature reaches a certain level, the hot melt adhesive film begins to soften. Below a certain temperature, the hot melt adhesive film will become brittle, so the choice of the hot melt adhesive film must fully consider the temperature change of the environment in which the product is located.
The viscosity of the hot melt adhesive film is divided into early tack and late tack. Only the early tack and the late tack are consistent, so that the hot melt film and the adherend remain stable. In the production process of hot melt adhesive film, it should be guaranteed to have antioxidant, halogen resistance, acid and alkali resistance and plasticity. The viscosity of the hot melt adhesive film varies depending on the material of the adhesive. Therefore, different hot melt adhesive films should be selected according to different materials.