1. The color requirements of the glue should be different. If the adherend itself has no special requirements for color, it is recommended to use a yellow hot melt adhesive. In general, yellow hot melt adhesives are better than white ones.
2. Surface treatment of the adherend. The surface treatment of the adherend by the hot melt adhesive is not as strict as other adhesives, but the dust and oil stain on the surface of the adherend should also be properly treated so that the hot melt adhesive can play a better role in the adhesion.
3. Operating time. Quick operation is the main feature of hot melt adhesives. The hot melt adhesive typically operates for about 15 seconds. With the widespread use of modern production methods, assembly lines, hot melt adhesives are becoming shorter and shorter, such as bookbinding and speaker manufacturing, which takes about 5 seconds.
4. Temperature resistance. Hot melt adhesives are temperature sensitive. When the temperature reaches a certain level, the hot melt adhesive begins to soften. If it is below a certain temperature, the hot melt will become brittle. Therefore, the choice of hot melt adhesive needs to fully consider the temperature change of the environment in which the product is located.
5. Sticky. The viscosity of hot melt adhesives can be divided into early tack and late tack. Only the early viscosity is consistent with the late viscosity, and the hot melt adhesive and the adherend can remain stable. In the production of hot melt adhesives, it should be ensured that it has oxygen resistance, halogen resistance, acid and alkali resistance and plasticity. The viscosity of the hot melt adhesive is also different due to the material of the adherend. Therefore, different hot melt adhesives should be selected according to different materials.