In this process, the laminating equipment does not require a binder heating and drying system, which greatly simplifies the laminating procedure, and the operation is very convenient. It can be turned on whenever it is used, and the production flexibility is large. At the same time, there is no solvent odor, no environmental pollution, and more importantly, it can be completely Avoid bubbles, delamination and other failures, the transparency of its finished products is extremely high, with broad application prospects and promotion value. The pre-coated film structure is composed of a substrate and an adhesive layer. The substrate is usually PET and BOPP film. From the perspective of material cost and processing technology, most pre-coated film substrates use BOPP film with a thickness of 12-20 microns. The adhesive layer The thickness is 5-15 microns. According to different processing equipment and process conditions, different thicknesses of adhesive layer are selected. The adhesive layer is divided into hot melt adhesive and organic polymer low temperature resin. The difference between the two is that hot-melt adhesives are made by blending and modifying several materials of the main tackifier resin, tackifier and modifier, while the organic polymer resin is a single polymer low-temperature copolymer.

        Due to technology, production equipment, and raw material restrictions, the pre-coated films (mostly hot-melt adhesives) produced by domestic equipment still have quality defects. Because there are production processes that rely on a process similar to that of coating the film, the colloid is dissolved with an organic solvent, and the roller is coated on the substrate film with a concave anilox roller, so there is insufficient solvent evaporation, and an odor occurs during operation. After coating, the solvent evaporates and the surface is prone to blistering. At the same time, because the hot-melt adhesive is blended with several kinds of polymer materials, during use, poor temperature control will cause degradation and cross-linking of the polymer in the hot-melt adhesive, resulting in poor coating surface. Some pre-coated film colloids are easy to adhere to the outer surface of the substrate, resulting in poor winding. Since the adhesive layer is thin and the surface is not activated, defects such as insufficient adhesion to the printed matter are likely to occur. Since the hot-melt adhesive is composed of several materials, the transparency after coating is significantly worse than the low-temperature pure resin pre-coating film.