Temperature is the core control parameter in the use of hot melt adhesive, directly affecting the melting state, fluidity, wettability and bonding strength of the adhesive. Different types of hot melt adhesives have strict operating temperature ranges, and the specific control points are as follows:
Temperature Control Points for Low-Temperature Adhesive (140-160℃)
The temperature range of low-temperature adhesive must be strictly controlled to avoid being too high or too low. Excessively high temperature will cause the adhesive to age and deteriorate, directly reducing the bonding strength; excessively low temperature will result in insufficient melting of the adhesive, poor fluidity, and prone to uneven glue application, which cannot fully wet the substrate, eventually forming false adhesion and affecting bonding stability.
Temperature Control Points for Medium-Temperature Adhesive (160-180℃)
Medium-temperature adhesive has extremely high requirements for temperature fluctuation, and the fluctuation range must be controlled within ±5℃. If the temperature fluctuation is too large, it will damage the viscosity stability of the adhesive, either causing glue overflow and waste, or insufficient glue application, which cannot meet the bonding requirements and affects the overall product quality.
Temperature Control Points for High-Temperature Adhesive (180-210℃)
The temperature control of high-temperature adhesive is directly related to the bonding effect and substrate protection. When the temperature is insufficient, the bonding strength will decrease significantly, especially for thick PVC edge banding or solid wood boards, which cannot form an effective "glue nail" - shaped adhesive film and result in unstable bonding; excessively high temperature may burn the edge banding, especially melamine paper and wood veneer edge banding, and accelerate the aging of the adhesive, shortening its service life.
Synchronous Temperature Control Points for Substrates
In addition to the temperature of the hot melt adhesive itself, the temperature of the substrate also needs to be controlled synchronously. In a low-temperature environment in winter, the boards and edge banding must be preheated to above 18℃ to avoid rapid heat loss after glue application, which leads to shortened open time, further affecting the wettability and bonding effect of the adhesive and ensuring the reliability of bonding.
Calibration Requirements for Temperature Detection
During the production process, the temperature display instrument of the edge banding machine must be calibrated regularly to ensure that the temperature displayed by the instrument is consistent with the actual working temperature, avoiding temperature control deviations caused by instrument errors, ensuring that the operating temperature of the hot melt adhesive is always within a reasonable range, and stabilizing the bonding quality.
