Color: The color requirements for hot melt adhesives should vary depending on the color of the materials being bonded. If the materials themselves do not have specific color requirements, yellow hot melt adhesive is recommended. Generally, yellow hot melt adhesive has better adhesion than white.
Surface Preparation of Materials: Hot melt adhesives are not as demanding on the surface preparation of the materials being bonded as other adhesives, but dust and oil should still be properly removed to ensure optimal adhesion.
Working Time: Fast working time is a major characteristic of hot melt adhesives. The working time of hot melt adhesives is generally around 15 seconds. With the widespread use of modern production lines, the working time of hot melt adhesives is becoming increasingly shorter.
Temperature Resistance: Hot melt adhesives are sensitive to temperature. At a certain temperature, the hot melt adhesive begins to soften; below a certain temperature, it becomes brittle. Therefore, the selection of hot melt adhesives must fully consider changes in ambient temperature.
Tackiness: Hot melt adhesives have two types of tackiness: early tackiness and late tackiness. Only when the early and late tack properties are consistent can the hot melt adhesive maintain stability with the bonded material. During the production process of hot melt adhesives, it is essential to ensure that they possess antioxidant, halogen-resistant, acid and alkali-resistant, and plasticizing properties.
