The bottom of the food packaging plastic bottle number analysis

According to China's national standards, plastic containers should be marked with triangular plastic recycling symbols at the bottom of the plastic containers, which is equivalent to the identity of plastic containers. Although this marking method is not mandatory, large and medium-sized enterprises generally mark plastic recycling labels in order to facilitate the recycling of plastic products. Consumers use plastic containers for foods to recognize the bottom logo.

Professor Dong Jinshi, deputy chairman and secretary general of the International Food Packaging Association, pointed out that the bottom of the plastic bottle is printed with three arrows consisting of triangles with a number ranging from 1 to 7. The triangle indicates that the material of the plastic bottle is “recyclable and renewable” and does not mean that it can be reused. Each number from 1 to 7 represents a type of material. If the product is made of several different materials, its main material is identified. This marking method originated in the United States and has been accepted and quoted by many countries including China. Although this labeling method is mainly used to facilitate the recycling of plastics, consumers can also use this label to know what materials are used for the plastic products used, which uses, and under what circumstances they should be used.

1, said PET (polyethylene terephthalate), mineral water bottles, carbonated beverage bottles are made of this material, heat-resistant to 70 °C, with high temperature liquid or heating deformation, harmful substances to the human body will Dissolution. Scientists have discovered that after 10 months of use, this plastic product releases carcinogens and is toxic to humans.

2. Denotes HDPE (high-density polyethylene), commonly used in the production of white medicine bottles, cleaning products, and bath products. Most of the plastic bags used in supermarkets are made of this material and can withstand high temperatures of 110°C, indicating plastic bags for food use. Can be used to hold food. Plastic containers containing cleaning products and bath products can be reused after being carefully cleaned. However, these containers are usually not well-washed, leaving the original cleaning products and become a breeding ground for bacteria. It is better not to recycle them.

3, said PVC (polyvinyl chloride), commonly used in the production of raincoats, building materials, plastic film, plastic boxes and other products, this material of plastic products easy to produce toxic and hazardous substances from two aspects, one is not completely in the production process Polymerized single-molecule vinyl chloride, the second is the plasticizer harmful substances. These two substances are easily precipitated when they are exposed to high temperatures and fats. Toxic substances can cause cancer when the food enters the body. At present, the container for this material is already relatively small for packaging foods. If you use this food package, do not let it heat.

4, said LDPE (low density polyethylene), cling film, plastic film are all of this material, heat resistance is not strong, usually qualified PE cling film at temperatures above 110 °C will appear hot melt phenomenon will leave Some plastic preparations that cannot be broken down by the human body. The use of cling film wrapped food heating, food oils can easily dissolve the harmful substances in the plastic wrap. Therefore, remove the wrapped plastic wrap before placing the food in the microwave oven.

5, said PP (polypropylene), microwave oven meal made of this material, resistant to high temperature 130 °C, poor transparency, this is the only plastic box can be put into the microwave oven, can be reused after careful cleaning. It is necessary to pay special attention to the fact that some microwave ovens have lunch boxes made of PP, but the lids are made of PS (PS). The PS has good transparency but is not resistant to high temperatures and cannot be put into the microwave oven together with the boxes. To be on the safe side, remove the lid before placing the container in the microwave oven.

6, said PS (polystyrene), which is used to make bowls of instant noodle boxes, foaming snack box material, not only heat and cold, but can not be put into the microwave oven, so as not to release due to high temperatures Chemicals. At the same time, such plastic containers cannot be used to hold strong acids (such as orange juice) and strong alkaline substances because they will decompose polystyrene that is harmful to the human body. Therefore, people should try to avoid packing hot food with fast food boxes.

7, said PC (polycarbonate) and other types, used to make bottles, space cups and other products, containing bisphenol A, the higher the temperature, the more release, the faster the speed. When people use this type of container, do not heat it, do not direct it in the sun; use baking soda powder to warm the water before the first use; dry naturally at room temperature; do not use a dishwasher or a dishwasher to clean the kettle; if the container has Any fall or breakage should be stopped, because if there is a slight crack on the surface of plastic products, it is easy to collect dirt; repeated use of old plastic appliances should be avoided.

After plastic bottles are recycled, they are not allowed to be used as food packaging, otherwise the quality supervision department will immediately cancel the production license of the relevant manufacturers. Due to the fact that certain properties have changed during the recycling process of plastic bottles, it is difficult to reuse them as plastic bottles, mostly for the production of non-food containers.