Laminating film is pre-adhesive plastic film and paper printing and then rewinding complex process. It is used first by laminating factory specifications according to the different format will glue coating after rewinding the film for use on the factory options, and then combined with the printed matter. Coating, that film is plastic film coated with adhesive, printed with the paper by heat and pressure so that after sticking together to form one paper and plastic products, processing technology. The coating of the print, due to surface more than a thin transparent plastic film surface is smooth and shining, to improve print gloss and fastness, graphic colors more vivid, rich three-dimensional, but also play a waterproof, stain, abrasion, folding, chemical resistance and so on.
(1) film thickness between 0.01-0.02mm, corona, or other methods of treatment, the surface tension should reach 4.0 x 10-2N / m, in order to have good wetting properties and bonding performance. Laminating film from the substrate and the adhesive layer composition, the substrate is usually polyester (PET) film and biaxially oriented polypropylene (BOPP) film. BOPP film with high transparency, good brightness, non-toxic and tasteless, water-resistant, heat-resistant, inexpensive, soft, etc., is the preferred coating process in the material, its thickness is about 12-20um, therefore, material costs and processing point of view, most of the laminating film BOPP film substrate used.
Laminating adhesive layer melt-and solvent evaporation are two kinds of processing equipment and process conditions according to the different choice of different thickness of adhesive layer, adhesive layer thickness between the 5-15um. Currently, the domestic laminating adhesive layer consists of low temperature hot melt adhesive or organic polymer resin composition. Hot melt adhesive is a sticky resin from the main and thickening agent, conditioning agent made of several materials, blending modification. Organic polymer resin is a low-temperature single-polymer copolymer. As the hot melt adhesive is a mixture of several materials, so transparent after the coating was significantly lower than the laminating temperature of pure resin.
Solvent evaporation process and the laminating film production film coating process is similar to colloidal organic solvent and then coated in a thin film substrate, it may not completely evaporate the organic solvent, coating operation, odor of operator injury (as opposed to the film coating process, the damage is much smaller) and so, after solvent evaporation coating, it tends to form bubbles in the print surface.