The roll-to-roll laminating machine is a special equipment that applies the adhesive to the plastic film of the reel and then dries it. That is, Xu-type laminating machine has two kinds of automatic machine and semi-automatic machine. Each type of machine has its unique features in structure and lamination process, but its basic structure and working principle are the same. It is mainly composed of five parts: unwinding, sizing, drying, compounding, rewinding, and mechanical transmission. , Automatic control of tension, automatic deviation adjustment of unwinding and other auxiliary devices.
        1. Unwind part. The unwinding of plastic film requires that the film always maintain a constant tension. If the tension is too large, it is easy to produce longitudinal wrinkles, otherwise it is easy to produce horizontal wrinkles, which are not conducive to the coating of adhesives and the compound with the printed matter. In order to maintain the proper tension, the unwinding part is generally equipped with a tension control device. Common ones include mechanical friction disc clutches, short-circuit AC motors, and magnetic powder clutches.
         2. Glue coating part. After unwinding, the film passes through the coating roller and enters the gluing part. The coating forms are: roller reversal type, concave type, direct glue without scraper and direct glue with scraper, etc.
        (1) Reverse roller coating. It is an indirect glue coating, which is the most widely used by various models. The glue supply roller brings out glue from the glue storage tank, and the glue scraping roller and the glue plate can scrape the excess glue back to the glue storage tank. The film counter-pressure roller presses the film to be applied to the surface of the glue roller after the glue is homogenized, and maintains a certain contact area, and the glue solution is continuously applied to the film surface under the action of pressure and adhesion. The amount of glue can be changed by adjusting the distance between the rubber roller and the rubber roller, and the rubber roller and the rubber sheet.
        (2) Concave glue application. It is composed of a metal rubber roller with a surface engraved on the surface and a group of film partition rollers. The gumming roller is directly immersed in the glue liquid, and the glue liquid is taken out from the glue storage tank with the rotation of the roller, and the excess glue liquid on the surface of the roller is scraped off by a scraper. Under the action of the film pressing roller, the glue in the groove of the roller is driven by the film to be coated which is directionally moved and is evenly spread on the film surface. The amount of glue can be controlled by adjusting the grid pattern on the surface of the coating roller shaft, the characteristic value of the adhesive, and the pressure value of the laminating roller.
        The advantage of concave coating is that it can control the amount of coating more accurately and coat evenly; however, the anilox roller is difficult to process and easy to damage, and it needs to be cleaned frequently. In addition, the coating requires higher adhesives.
       (3) No-squeegee roller extrusion coating. The glue roller is directly immersed in the glue liquid. During the coating, the glue roller brings out the glue liquid and passes through the glue roller. After the glue is evenly glued, the glue is applied by the pressing force between the film pressing roller and the glue roller.
        During extrusion, the pressure, adhesive performance index and coating speed determine the thickness of the adhesive layer. The amount of glue applied is achieved by adjusting the squeezing force between the glue roller and the glue roller, the glue roller and the laminating roller. Therefore, there are high requirements on the surface accuracy, cylindricity and radial runout tolerance of each roller.
       (4) There is a scraper to apply glue directly. The glue roller is directly immersed in the glue solution and continuously rotates to drive the glue solution from the glue tank. After removing the excess glue solution by the scraper, it comes into contact with the film surface to complete the glue application.

        The roll-to-roll laminator has the force of direct squeegee coating. The design requires that the squeegee scrape the glue on the surface of the glue roller, that is, the straightness of the blade edge of the glue blade and the surface accuracy of the glue roller are quite high. The squeegee is generally made of stainless steel belt with high flatness, smoothness and good elasticity.