Coating machine extrusion coating is the application of a molten web of synthetic resin to a base material. It is a versatile coating technology used for the economical application of various plastics, especially polyethylene, cardboard, corrugated fiberboard, paper, aluminum foil, cellulose, non-woven fabrics or plastic films. What are the functions and characteristics of the coating machine extrusion coating technology? Functions of coating machine extrusion coating technology 1. Coating: The actual process of extrusion coating involves extruding the resin from the slit die directly onto a moving web at a temperature of up to 320°C, which can then pass through the roller gap consisting of a rubber-covered pressure roll and a chrome-plated cooling roll of the coater. The latter cools the molten film back to a solid state and gives the plastic surface the desired finish. The paper web is usually much faster than the resin is extruded from the die, and the resulting coating thickness is proportional to the speed ratio and the slit gap. 2. Lamination: Extrusion lamination is a similar process, except that the extruded hot molten resin acts as a bonding medium for the second material web. 3. Coextrusion: Coextrusion is also a similar method, but two or more extruders are connected to a single die, where the separately extruded melts are put together and finally extruded into a multi-layer film.The coating machine is a kind of production equipment mainly used for the surface coating process of film, paper, etc. It brings convenience to people's coating production. Its rewinding and unwinding are equipped with full-speed automatic film splicing mechanism for use and operation, and the tension closed loop automatically controls the operation of the coating equipment. Therefore, it is simple and fast to run during use, but the machine will inevitably wear out during use. The transmission parts of the coating machine are seriously worn during operation. One is: the wear of the drying cylinder shaft head, and the other is: the wear of the paper roll bearing chamber. When solving it, it is generally repaired by surfacing, thermal spraying, brush plating, etc. If the machine is seriously worn, it is best to take it to a regular store for repair! In addition, when using the machine in daily life, it should be operated according to the correct operation, and the daily maintenance of the machine should also be done well, so as to reduce the wear of the machine and extend the service life of the machine! The coating machine is used for the coating and production of BOPP sealing adhesive tape. The rolled substrate is coated with a layer of glue, coating or ink with specific functions, and then rolled up after drying.It uses a special high-speed coating head, which can effectively reduce the occurrence of bubbles. The reel of the coating machine is equipped with a full-speed automatic film splicing device and automatic tension closed-loop control. Characteristics of the extrusion coating technology of the coating machine The drying of the slurry after coating by the coating machine consists of the following two heat and mass transfer processes: 1. The evaporation and vaporization process of the surface liquid. The wet coating exchanges heat with the dry hot air, absorbs the heat of the dry air, and the liquid on the surface of the coating continuously evaporates into steam and enters the air, and the steam is taken away by the dry air. When the liquid content of the wet coating is relatively high (above the critical moisture content), the speed of the surface vaporization depends on the following factors: A. The surface air flow speed; B. The humidity of the dry air; C. The temperature of the dry air.