Hot melt adhesive is a plastic adhesive whose physical state changes with the temperature within a certain temperature range. There are high temperature hot melt glue, mid-temperature hot melt glue, and low tmperature hot melt glue. The chemical properties remain unchanged, it is non-toxic and tasteless, and it is an environmentally friendly chemical product. Because the product itself is solid, it is easy to package, transport, store, solvent-free, pollution-free, non-toxic; as well as simple production process, high added value, high bonding strength, fast speed and other advantages.
Hot melt adhesive product selection
First, the color requirements of the glue should be different. If the attached object itself has no special requirements for color, it is recommended to use yellow hot melt adhesive. Generally speaking, yellow hot melt adhesive is more viscous than white.
2. Surface treatment of the object to be attached. The surface treatment of the hot melt adhesive is not as strict as other adhesives, but the dust and oil on the surface of the adhered should also be properly treated, so that the hot melt adhesive can play a better role in bonding.
3. Working time. Fast operation is a major feature of hot melt adhesives. The working time of hot melt adhesive is generally about 15 seconds. With the wide application of modern production methods - assembly line, the working time of hot melt adhesive is getting shorter and shorter, such as book binding and speaker manufacturing for hot melt adhesive. It takes about 5 seconds.
Fourth, anti-temperature. Hot melt adhesives are more sensitive to temperature. When the temperature reaches a certain level, the hot melt adhesive begins to soften. Below a certain temperature, the hot melt adhesive will become brittle. Therefore, the choice of hot melt adhesive must fully consider the temperature change of the environment where the product is located.
Five, stickiness. The viscosity of hot melt adhesive is divided into early viscosity and late viscosity. Only when the early viscosity and late viscosity are consistent, can the hot melt adhesive and the adherend remain stable. In the production process of hot melt adhesive, it should be ensured that it has oxidation resistance, halogen resistance, acid and alkali resistance and plasticity. Depending on the material of the object to be attached, the viscosity of the hot melt adhesive is also different. Therefore, different hot melt adhesives should be selected according to different materials.
