Vest bag is one of the packaging bags used by many commodities, usually most of them are disposable. When commodities flow from the production unit to the hands of consumers or to the opening and use of commodities, the packaging materials complete its mission, as the recycling or disposal of waste materials. Therefore, for packaging materials, one is for better performance to meet the needs of protection and promotion of commodities. The second is for the purpose of keeping the cost as low as possible. In today's so-called general plastics, plastics such as polyethylene, polypropylene, excellent performance, a large number of materials with printed back center bags, low price and other common characteristics, plastic packaging materials can be selected. The second is the large-scale production and sex Can be better, but more expensive general engineering plastics, such as thermoplastic polyester. As for the expensive special engineering plastic thickened vest bag production materials, although it has unique advantages in some properties, but due to economic reasons, it is specialized in the production of vest bag materials, which are generally not used for packaging materials.
The printing of vest bag can also be said to be the core. No matter how good the bag material is, if it is destroyed in the printer, everything will be in vain. Printing quality is affected by printing ink, diluent, layout, printer technology and other factors, which need to be strictly controlled by the manufacturer.
In the process of actual combination of sealing and cutting, cutting, welding and cutting the printed plastic film to form the sealed part materials of three or two vest bags, and then finalizing the design by punching machine (such as vest bag, buckle bag style). The operation method of the sealing and cutting machine is very simple: the electric plastic film is placed on two rows of metal heat sealing plates in the direction of the plastic film, horizontally, one row and one row vertically, and then the sealing work is carried out from two directions respectively. The sealing principle is that the metal temperature is generated by electric heating. When the temperature reaches the thermal temperature of the plastic film, the edge of the plastic film can be bonded. The hot bonding method also has requirements for the plastic film. The material must have good heat-resistant sealing performance and low melting point.