What is the principle of self supporting bag and vacuum bag
In life, some foods, such as crisp and fragile food, easy to deform and take oil, have sharp edges and corners or have high hardness, which will puncture the vacuum bag and other food. After vacuum inflatable packaging, the filling pressure inside the vacuum bag is stronger than the atmospheric pressure outside the packaging bag, which can effectively prevent the food from crushing and deformation, and does not affect the appearance of the packaging bag and printing decoration.
The air filled vacuum bag is filled with nitrogen, carbon dioxide and other gases after extracting the vacuum. Nitrogen is an inert gas and plays a filling role. Therefore, the vacuum packaging bag is used to maintain positive pressure to prevent the air outside the bag from entering the bag, which plays a protective role on food. Carbon dioxide has the activity of inhibiting mold, spoilage bacteria and other microorganisms
Vacuum bag, also known as close fitting moisture-proof bag, aluminum foil bag and aluminum plastic composite bag, is generally made of PET / Al / CPE or PET / NY / Al / CPE. Among them, pet has good printing effect, NY has low oxygen permeability, Al has strong barrier and light barrier, CPE is the inner layer of packaging. Glue: water soluble glue (more hygienic, environmental protection, no solvent residue) this product has good anti-static, oxygen proof, shielding, moisture-proof, shading functions and excellent heat sealing property. According to the special requirements of users in various industries, the self-supporting bag can add anti-static function, printed product description, company trademark and anti-static logo without changing the product performance. It is suitable for vacuum packaging, electronics, communication, national defense and military products.
Expanding knowledge: key points of BOPA printing
BOPA film is easy to absorb moisture and deform. Therefore, it is necessary to ensure that the environmental humidity of the printing machine should not be too high (if there is no dehumidification measures and the environment with high humidity is not suitable for nylon film); the unprinted film can not damage its original aluminum film packaging film, and it should be printed immediately after opening, and the nylon film should be preheated during printing (if there is no preheating device on the machine, the printing plate can be installed after the second color, leaving the first color for printing For preheating), the preheating temperature should be 50 ~ 80 ° C; the printing tension should be appropriately reduced; the pressure should be moderate; the ink adaptability should be strong, depending on the different product structure. If it is a cooking bag, cooking ink must be selected. After printing, the product must be sealed and laminated. K-coating film (Kop / kPa / kpet) printing points: because the thickness uniformity of k-coating film is not very good, the surface is not smooth, and PVDC is rigid and brittle. When printing, the printing tension and embossing pressure can not be too large, the overprint is difficult, the ink transfer is poor, and the printing dot is easy to appear when printing the shallow screen (part of the dot is lost), so it is necessary to use high hardness pressing Roll for printing. In addition, due to the selectivity of solvent oil, the coating may be dissolved when the solvent is not used. The residual solvent of printing film is large and easy to adhere. Therefore, special attention should be paid to drying and cooling. The OPA process can be used in the printing of Matt Film on its smooth surface, but because the surface of the matting layer can not withstand high temperature, it is necessary to control the drying temperature. Pearlescent film using surface printing ink for surface printing, and try to choose a good transparency of the surface printing ink. When self-supporting bag heat shrinkable printing adopts very low drying temperature, special heat shrinkable ink should be selected (silver ink layer should be able to heat shrink without falling off). If it is PVC heat shrinkable film, solvent solubility should be considered. In order to stretch the PP, PE film, the tension should be very small when printing, and the overprint is very difficult. The printing deformation should be fully considered in the pattern design. In a word, for different printing substrates, we must make adjustments in ink selection, plate making design and printing process to ensure the quality of products to meet the requirements. In addition, some high barrier coating materials should not be printed on the coating surface as far as possible in case of damaging the barrier coating. www.dgbpk.com/
Dongguan Beite packaging materials Co., Ltd
Dongguan special bag, plastic bag, plastic bag, plastic bag