Fresh-keeping bags are widely used in life, so what is the safest material for fresh-keeping bags?Polyethylene and polyvinylidene chloride materials are safe.Fresh-keeping bags are divided into polyethylene (PE), PVC (pvc), polyvinylidene chloride (PVDC) and other types.1, is polyethylene, referred to asPE, This material is mainly used for food packaging. The film we usually buy for water, fruits and vegetables, including semi-finished products purchased in supermarkets, all use this material.2, polyvinyl chloride, referred to aspvc, this material can also be used in food packaging, but it has a certain impact on the safety of the human body.3, polyvinylidene chloride, referred to asPVDC, mainly used for the packaging of some cooked food, ham and other products. Among these three plastic wraps,PEandPVDCThe plastic wraps of these two materials are safe to the human body and can be used with confidence.pvcPlastic wrap contains carcinogens, which are harmful to the human body. Therefore, when purchasing plastic wrap, you should choosePEPlastic wrap as well. Generally, there are reference information such as specific implementation standards, materials used, and operating temperature range in the outer packaging instructions of regular manufacturers. with polyvinyl chloride (pvc), polystyrene (EPS) compared to other materials such as polyethylene (PE) or polypropylene (PP) is relatively safer due to its better chemical stability and simpler composition. Most of the food preservation bags and plastic wraps produced by regular manufacturers on the market are made of polyethylene (PE) or polypropylene (PP).Relevant knowledge development:If you have a plastic bottle in your hand, turn it upside down, and at the bottom, you’ll see a triangle symbol with a number printed in the middle. the number is its”ID card”. The number in the center indicates the serial number, and the English below indicates the name of the plastic material.11No. Plastic: Don’t ReuseProducts: It is often used to make mineral water bottles and carbonated beverage bottles.explain:1No. plastic, namely polyethylene terephthalate (PET). This material has poor heat resistance, and the maximum operating temperature does not exceed70℃.Once heated or filled with boiling water, it will deform and dissolve harmful substances.”1″No. plastic used10months later, carcinogens may be releasedDEHP, and the more times it is reused, the higher the probability of releasing carcinogens and the more bacteria will grow.Note: This type of plastic bottle cannot hold hot water, and do not reuse it. It is best to throw it away after drinking.twenty twoNo. Plastic: RecyclableProduct: It is mostly used to make containers for cleaning products and bath products.explain:”2No”stands for high-density polyethylene plastic(HDPE), this ingredient is extracted from petroleum, and it has undergone high temperature and high pressure during production. It has a high density, is very strong, and can be reused.Note: However, if the cleaning is not thorough, it is recommended not to recycle.33No. Plastic: relatively the least safeProducts: It has a wide range of applications, and is often used to make raincoats, garbage bags in daily life, plastic greenhouses and rubber pipes for agriculture, etc.explain:”3No”Represents polyvinyl chloride(PVC), good performance, wear-resistant, acid-resistant, the disadvantage is that it is not heat-resistant and highly toxic.Note: It is not recommended to use3No. plastic bags for food.44No. plastic: the best flexibilityProducts: Commonly used in the production of plastic wrap, plastic film and other materials.explain:”4No”Represents low-density polyethylene plastic(LDPE), breathable impermeable, heat resistance is not strong.Note: If it is marked on the plastic wrapPE(polyethylene), indicating that it is not resistant to high temperatures, and markedPVDC(Dichloroethylene) is resistant to high temperatures and can usually withstand150℃ high temperature, can be used for microwave heating.55No. Plastic: high temperature resistant (100℃ above)Products: raw materials for making plastic cups and plastic lunch boxes, which can be used for food storage and microwave heating.explain:5No. Plastic Material Polypropylene (PP), is the relatively strongest heat-resistant plastic. Generally speaking, this plastic material is milky white, translucent, and uniform in color. Some also add a transparent agent (harmless to the human body) to make it fully transparent. It can be reused after cleaning.Note: It is not recommended to choose ones with peculiar smell and bright colors. because purePPPlastic has no peculiar smell, and adding too much color may be to cover up the defects of the product material itself.66No. plastic: heat-resistant and cold-resistant disposable plasticProduct: Commonly used in the production of instant noodle boxes in bowls and fast food boxes.explain:”6No”Represents polystyrene(PS), heat-resistant (heat-resistant60-70℃), cold resistance, but can not be put into the microwave oven, and can not be used to hold strong acid(such as orange juice), Strong alkaline substances, may decompose polystyrene which is harmful to human body and easy to cause cancer.Note: It is best not to pack hot food in a snack box. Moreover, it is difficult to degrade itself and is harmful to the environment. It is recommended not to use it as much as possible.77No. plastic: relatively safeProducts: mostly used in the manufacture of baby bottles, space cups, etc.explain:”7No”stands for polycarbonate(PC)and other classes.PCIt is a material that is widely used, especially polycarbonate, which has a stable structure and few additives. It is currently considered a relatively safe plastic.Suggestion: Try not to pour boiling water into the Space Cup.