Process flow of protective film production

- Apr 03, 2020-

Film blowing process: The blown film is a film made by plasticizing the plastic in an extruder, extruding it into a film tube through a ring die, and inflating and cooling it with compressed air. Film blowing machine is divided into single-layer film blowing machine and multi-layer co-extrusion film blowing machine. Wuhan Light Machine and Guangdong Dongming are relatively well-known manufacturers of film blowing machines.

Casting process: The casting film generally adopts a multi-layer coextrusion process. The molten resin is extruded through a T film head and then cooled by a chill roll. PE, PP and PA can be produced by casting.

Biaxial stretch process: Biaxially stretched film is a film made by melting and extruding plastics at high magnifications in both vertical and horizontal directions. It changes the arrangement of polymer molecules and segments to give them a high degree of The plane orientation and crystallinity are improved, which significantly improves the mechanical strength and surface finish of the film.

Vacuum aluminizing process: In a high vacuum of 10-2-10-3Pa, aluminum is vaporized by resistance, high frequency or electron beam heating, and condenses into a uniform metal film on the cooled film. There are three types of evaporation processes: batch, semi-continuous, and continuous. Commonly used plating materials are PET, PP, PA, PT, PE, PVC and so on.

Gravure printing process: Gravure printing machine is composed of unwinding device, printing device, ink transfer device, drying device, tension control device, register control device and winding device. It immerses the printing plate in the ink tank, and then removes the ink from the non-engraved parts by a doctor blade, and then transfers the ink to the printing substrate under the action of the impression rubber roller.

Composite process: Compounding several kinds of single-performance materials into new materials with comprehensive properties by taking advantage of each other. Compound methods include: dry compound, extrusion compound, thermal compound, and special coating compound (such as coating PVDC layer).

Slitting process: Slitting process is a process of dividing large-size film rolls into required specifications. With the increasing application of automatic packaging equipment, more and more forms of film rolls leave the factory.

Inspection process: semi-finished products and finished products are re-rolled on the inspection machine. For example, if the errors in the shape, size and color of the patterns fed back by the sensor and the standard samples entered into the computer exceed a certain range, the inspection machine will automatically stop for inspection. Out. The inspection process can reduce waste in subsequent processes and improve product quality.

Bag-making process: The composite flexible packaging material can only be used by making various packaging bags, and the packaging bags are realized by a bag-making machine. At present, the commonly used bag types include three-side sealed bags, zipper bags, conjoined stand-up bags, bottomed stand-up bags, zipper stand-up bags, back-sealed bags, back-sealed fold bags, two-side-sealed bags, thermal fuse bags and other forms.