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Plastic Products The meaning of the bottom number
- Sep 05, 2018 -

Plastic in our lives everywhere, plastic products are made of different materials, materials, applications are different.

The numbers on the bottom of the plastic bottle represent different materials. The number "1" represents polyethylene terephthalate, or pet. Mainly used for mineral water bottles, carbonated, juice drink bottles and soy vinegar bottles.

Pet bottle heat-resistant temperature of 70 degrees Celsius, only suitable for warm drink or frozen drink, installed boiling water or heating is easily deformed, harmful substances will dissolve. The digital "2" represents high density polyethylene, or HDPE.

HDPE is made of composite films with other plastics and is also used in aquatic products. The digital "3" represents polyvinyl chloride, or PVC, which is also used to make intravenous infusion bags and disposable sterile infusion devices because of their low price. However, long-term use can lead to DEHP accumulation of harmful substances.

Therefore, from a safety point of view, the pharmaceutical industry to choose non-PVC materials is the future trend. The digital "4" is low density polyethylene, or LDPE. Number 4th plastic is used for packaging.

LDPE is mainly used for the production of food preservation film and food packaging plastic bags. The number "5" is polypropylene, i.e. pp. One is to make containers. PP and its material, pp can be put into the microwave in the plastic container, but also reusable plastic containers, can be used as storage containers for food, oil and condiments. The second do is the packaging film, there is no stretching and biaxial stretching.

Non-stretched polypropylene (CPP) is commonly used in the packaging of dim sum, bread, fruit, etc., and biaxial stretch polypropylene (BOPP) is a flexible packaging material comparable to cellophane. The number "6" is polystyrene, which is PS. PS is mainly processed into film and foamed plastics on the packaging.

Film for the packaging of fruits and vegetables, foam is used in bowls of instant noodles and fast food boxes, but not high temperature, so it can not be placed in the microwave oven directly to heat, so as not to release the toxic chemicals due to high temperature. The digital "7" is polycarbonate, i.e. PC or other plastic. PC material made of plastic containers, may release toxic bisphenol A, the higher the temperature release more, the faster the speed, so use do not heat, also do not in the sun straight sun.