There are two kinds of common plastic (structure: synthetic resin, plasticizer, non disordering agent and pigment) bags on the market (SH ì ch ǎ ng), one is plastic bag and the other is regeneration plastic bag. The difference between them is raw material (raw material) The former is made of brand-new polyethylene plastic particles, which is characterized by smooth, soft, colorless, tasteless and non-toxic, and is generally used in food packaging bags; the latter is recycled plastic garbage or waste, which is screened and processed (Ji ā) It is made of plastic particles after g അ ng), characterized by insufficient color, colorful and rough surface (C ū Due to the disordered sources of raw materials and certain toxicity, this product is generally used in the packaging of agriculture or ordinary household products. At present, the Ministry of health of the state (Nowadays) has issued a circular to strictly define the scope of production and use of recycled plastic bags (Gu ī) D ì ng), it is forbidden to use in any food packaging products, because it contains toxicity, it has a great impact on people's health. Vacuum bag is in the extraction of vacuum, and then filled with nitrogen, carbon dioxide and other gases. Nitrogen is an inert gas, which plays a filling role and keeps the vacuum bag under positive pressure, so as to prevent the air outside the bag from entering the bag and protect the food. Carbon dioxide has the activity of inhibiting mold, spoilage bacteria and other microorganisms. Some foods, such as crisp and fragile food, easy to deform and take oil, sharp edges and corners or high hardness will puncture the vacuum bag. After vacuum inflatable packaging, the filling pressure in the vacuum bag is stronger than the atmospheric pressure outside the packaging bag, which can effectively prevent food from crushing and deformation under pressure, and does not affect the appearance of the packaging bag and printing decoration. With the promotion of small vacuum bag packaging and the development of supermarkets, its scope of application will be more and more extensive, some will gradually replace hard packaging. Plastic bags are essential items in people's daily life, and are often used to hold other items. It is widely used because of its cheap, light weight, large capacity and easy to store, but it is forbidden to produce and use because of its long degradation cycle and difficult handling problems. www.dgbpk.com
Nowadays, dark plastic bags, such as black, red and blue, are mostly recycled plastic products. They can't hold food. Ultra thin plastic bags (thickness less than 0.025mm) are also forbidden to hold food. Generally, aluminum foil bags should be kept away from direct sunlight and fire sources. They can be kept for 2 years at room temperature of 25 ℃. Aluminum foil bag is also known as polyamide 66 or nylon 66. Yellowish translucent or milky white opaque resin. The relative density is 1.14-1.15, and the melting point is 259-267 ℃. Wear resistance, oil resistance, self-lubricating, heat resistance, strength, rigidity is the highest aliphatic nylon varieties. The tensile strength is 75.9-82.9mpa, the compressive strength is 91mpa, the impact strength (notch) of cantilever beam is 4Kj / m, the thermal deformation temperature is 75 ℃, the hardness is R120, the volume resistivity is 1015 Ω· cm, the dielectric strength is 35kV / mm, and self extinguishing. It is prepared by polycondensation of adipic acid and hexanediamine. It can be processed by extrusion, injection molding and blow molding. It can be reinforced, filled and alloyed. It is widely used as the packaging material of fiber and tire curtain vacuum bag. It is usually made of double-layer composite film or three-layer aluminum thin composite film. There are two types of vacuum packaging machine: cavity type and external suction type. China's vacuum packaging technology was developed in the early 1980s, and the vacuum inflatable packaging technology began to be used in the early 1990s. The vast majority of these recycled plastic bags are produced by small (x ǐ Ao x ǐ ng) companies or family workshops. A considerable number of these recycled plastic bags are recycled and processed by using collected waste plastics, industrial wastes and rubber wastes discarded by medical institutions, and are not disinfected (poison) (Xi ā o) D ú) treatment, containing serious bacteria and carcinogens. Packaging cooked food directly imported with this kind of plastic products will cause serious consequences to the health of consumers.
Dongguan Beite packaging materials Co., Ltd