Pre-coated film lamination is a commonly used post-press printing process that can improve the surface gloss, wear resistance, and water resistance of printed products. However, if the lamination quality is poor, it will affect the overall effect of the printed product.
The three major factors affecting the quality of pre-coated film lamination are
Temperature
Temperature is one of the key factors affecting the quality of pre-coated film lamination. The temperature determines the melting state and flow properties of the hot melt adhesive, as well as its diffusion ability to the three materials of BOPP film, ink layer, and paper substrate, and the crystallinity of the hot melt adhesive. Only by correctly controlling the temperature of the working area can the solid hot melt adhesive layer of the pre-coated film be completely melted into a viscous state and have appropriate, to achieve the wetting and bonding of the printed product, and at the same time ensure the instant solidification after bonding, so that the surface of the finished product is smooth, bright and wrinkle-free.
Pressure
Pressure is another important factor affecting the quality of pre-coated film lamination. Appropriate pressure should be used while controlling the lamination temperature correctly. The surface of printed paper is usually not very smooth. Only under appropriate pressure, the hot melt adhesive in a viscous state will fully wet the surface of the printed product in the process of driving away the air on the surface of the printed product, so that the adhesive will diffuse, dislocate and achieve good bonding between the ink layer and paper molecules of the printed product, forming a complete lamination product.
Speed
The lamination speed determines the time for the pre-coated film and paper printed product to achieve bonding. When the temperature and pressure are fixed, different lamination speeds will cause changes in the lamination effect. Due to the limitation of the upper temperature limit and pressure supply, it will only change from the direction smaller than the set value, and with the increase of speed, it will decrease, the heat pressure will decrease, and the composite effect will become worse. The running speed is too fast, the bonding is not firm, and fog will appear. It is too slow and inefficient, and even bubbles will appear.
In order to obtain high-quality lamination effect, it is necessary to comprehensively consider the temperature, pressure and speed, and adjust them according to the specific situation.
#Pre-coated Film Lamination #Lamination Film