Effect of Temperature & Humidity on Dry Lamination-1
As practitioners, they shall have a certain understanding of the influence of temperature and humidity on the entire process of dry lamination. Here’s a summarize to let everyone deepen the understanding of the influence of temperature and humidity on the dry lamination and improve the operator's attention.
"Temperature and humidity" as key control points of the dry laminating process, the control effect of different production workshops may be very different. Classified management and effective balance of temperature and humidity can eliminate the adverse effects and ensure the quality and stability of dry laminated products.
Temperature & Humidity of Processing Environment-1
Ambient temperature and humidity refer to the temperature and humidity of the space where the laminated equipment and materials are located. According to the operating habits and conventional product structure types, it is generally believed that the best range of the temperature is 18~26℃, while the relative humidity is 45%~60%, which are the most suitable conditions for the process, materials, equipment and operators. In the dry laminating line, far exceeding the suitable range of environmental conditions is the biggest concern, which will cause adverse impact on the finished product. For example, the film(e.g. Nylon) will be deformed due to the moisture and the performance of adhesive may be changed in the hot and humid environment. Moreover, the adhesive effect and coating effect will be also changed in the cold and dry environment. The sudden temperature change also affects the properties of laminated films, especially resulting in electrostatic hazard.
1. High Temperature & High Humidity Conditions
It commonly appears in the summer in southern China, especially in the Pearl River Delta and the southern coastal areas, as well as the "plum rainy season" in the middle and lower reaches of the Changjiang River. In some lamination workshops with weak facilities, the temperature exceeds 35℃ and the humidity exceeds 90%. In such conditions, all the pipelines that the cooling water and cold air pass through, will generate a lot of condensation without thermal insulation treatment measures. And the solvent will accelerate volatilization, which will absorb heat and reduce the temperature of the gluing system leading to condensation happen in the gluing system. It is a big hidden danger of dry laminating process, resulting in incomplete glue curing, residual solvent, and poor appearance of the final products.
2. Low Temperature & High Humidity Conditions
It commonly appears in the early spring or continuous rainy winter in the south, during which the air is full of moisture and the object surface temperature is relatively low. If the workshop is not well enclosed, it will cause condensation on the surface of the ground, walls, equipment and so on, accelerating the corrosion of metal parts. What’s more, once the condensation is mixed into the glue, the water will reacts with isocyanate and depleting the active ingredients in the curing agent, resulting that the glue is not fully cured. Therefore, we need to pay more attention to the adverse effects of moisture
