The final step of the food packaging bag printing process is the key step to determine whether the packaging bag can leave the factory. What is the main step?
Food bags Tang renshen packaging bags food packaging bags inspection items of food packaging single film bags are mainly divided into the following categories: the appearance of food packaging bags shall not have defects such as bubbles, perforations, water lines, ribs, poor plasticization, fisheye stiffness, etc. that hinder the use of food packaging bags.
The error of specification, width, length and thickness shall be within the specified range.
Physical and mechanical properties include tensile strength and cracking elongation, which reflects the product's ability to stretch during application. If this item is not up to standard, the food packaging bag will simply break and be damaged during application.
First, the inspection items of food packaging composite film bags are mainly divided into the following categories: the appearance should be flat, no scratches, burns, bubbles, broken oil and wrinkles, heat seal is flat, no virtual seal.
The film shall not have cracks, pores and composite layers separated. No impurities, foreign matters and oil stains.
Bagged soaking liquid shall not have peculiar smell, odor, dirt and decolorization.
Second, the physical and mechanical properties include tensile strength and cracking elongation, which reflects the product's ability to accept stretching during application. If this item is not qualified, in the process of application, the food packaging bag is simply broken and damaged.
In addition, it also includes gas barrier targets such as gas transmission;
Oil resistance target, heat resistance, cold resistance, medium resistance;
The sealing and peeling force of the bag, the pressure resistance and drop resistance of the bag and other targets reflect the reliability of the internal packaging maintenance of the food packaging bag.
Third, the processing of plastic film bags must be closed by heating, and the plastic has the problems of cracking, oxidation, degradation and metamorphosis when heated. Therefore, when processing plastic films or bags with resin, additives such as antioxidants and heat stabilizers should be added to the resin.
Some packaging film bags also require antistatic, anti-condensation and high smoothness due to packaging process and mechanical or content requirements, so they also need to participate in antistatic agents, anti-fogging agents, lubricants, opening agents and other additives.
All these additives must first be tested by GB15139 'food safety toxicology review procedure' to prove that they are non-toxic before they can be used, but there is also a constraint of increasing the amount.
Therefore, in the products in process, these low molecular weight substances that can be extracted, that is, transpiration residues, or things that can be oxidized and transformed, that is, potassium permanganate consumption, cannot exceed the specified amount, if you exceed it, you can't use it.
Therefore, there must be corresponding hygiene standards for the molded products. The purpose is to avoid misuse and misuse of additives, it is to better ensure that the data of direct packaging and touching food have high hygiene and safety performance.
At present, China is not used to the development of professional products in the development stage of technical specifications for flexible packaging, such as the rapid development of composite data flexible packaging data structure, the only materials used are PE, PP, PVC, PVDC, PET, PA, EVOH, EVA, EEA, EMA, ionic polymer, various inks, adhesives and other dozens of materials, the existing composite packaging data specification only involves BOPP, LDPE, BOPA, PET, aluminum foil and other data, while the inspection of composite film data with many other structures has no specification to follow, can only be implemented with reference to existing specifications and related specifications.