The plastic recycling symbol is the triangle made up of three arrows printed on the bottom of plastic products, with a number from 1 to 7 inside. Many consumers and buyers have seen it but are unclear about what each number represents in terms of material, whether it’s safe for food contact, and whether it can be recycled. This comprehensive guide to the plastic recycling symbol will break down the identity, safety level, and recyclability of each number from 1 to 7. As a flexible packaging manufacturer, Huashu Packaging works with various plastic materials every day. We hope to provide you with an industry perspective to help you understand this small triangle, so you can make informed choices when purchasing plastic products and ensure that the recycling process truly makes full use of resources.
The Origin of Plastic Recycling Symbols: From Birth to Widespread Use
The plastic recycling symbol was designed and introduced by the Society of the Plastics Industry (SPI) in 1988, originally intended to help recycling sorters quickly identify the type of plastic. The designers chose a triangle with an arrow to symbolize that plastic can be recycled. Later, this symbol system was widely adopted globally and has become one of the most common markings on plastic products. The symbol consists of three parts: the three arrows in the outer ring, the number in the center, and the English abbreviation for the material below the number, such as PET, HDPE, and PP. It is important to note that the number inside the triangle represents the resin identification code, which does not equate to the recyclability level or the safety level. This is a common misunderstanding among consumers—larger numbers do not mean safer materials, and smaller numbers do not mean the material cannot be recycled.
Items 1 and 2: PET and HDPE, the most commonly used packaging materials
1 represents PET (Polyethylene Terephthalate), commonly used for mineral water bottles, beverage bottles, and some food packaging boxes. PET has high transparency, light weight, and good gas barrier properties, making it suitable for carbonated drinks and drinking water. However, it is not heat-resistant and should not be used for repeated heating. Number 2 represents HDPE (High-Density Polyethylene), which is commonly used for milk containers, shampoo bottles, and cleaning product bottles. HDPE is resistant to acids and alkalis, can withstand low temperatures, and has excellent chemical stability. It is also one of the materials with a high recycling rate in the recycling system. For more details about PET material, please refer to ourPackaging Film ClassificationThese two materials are the most commonly used in daily life and have the most mature recycling systems. Please remember to empty and flatten the bottles before disposing of them into the recyclable waste bin.
Items 3 to 5: PVC, LDPE, and PP, each with restrictions and applications
Number 3 represents PVC (polyvinyl chloride), commonly used in food wrap, some pipes, and toys. PVC requires the addition of plasticizers during production and may release harmful substances when burned, so it is gradually being phased out in the food packaging industry. When choosing food wrap, prefer PE material. Number 4 represents LDPE (low-density polyethylene), which is commonly used in plastic bags, food wrap, and garbage bags. It has good flexibility but relatively poor heat resistance. Number 5 represents PP (polypropylene), which is used in takeout containers, yogurt cups, and some food packaging bags. PP has excellent heat resistance and can withstand temperatures around 120°C, making it one of the few plastics suitable for microwave use. If you need a high-temperature resistant packaging solution, please consider our options.High Temperature Sterilization Bag Complete Guide。
No. 6 and 7: PS and 0 other 1, vigilance and attention coexist
The number 6 represents PS (polystyrene), commonly used in disposable foam food containers, cup lids, and plastic spoons. PS is brittle and has poor heat resistance, potentially releasing styrene monomers at high temperatures. It is not recommended for use with hot food or for microwave heating. Many cities have restricted its use. The number 7 represents other materials, a broad category including PC, PA, ABS, and biodegradable plastics like PLA. Among these, PC has attracted significant attention due to potential bisphenol A content, while biobased materials like PLA represent new directions in environmental protection. When you see the number 7, be sure to check the specific material designation— it could be the most eco-friendly option or a material unsuitable for food contact, requiring judgment based on product descriptions. The difference between biodegradable materials and ordinary plastics is discussed in ourThe impact of the plastic restriction policy on the packaging industryThere is a more systematic analysis in this article.
Summary and Recommendations
The core value of plastic recycling labels is to help consumers understand the material, distinguish its purpose, and correctly sort it. Remember these key points: the numbers only indicate the type of resin, not safety or recyclability level; for food packaging, prefer PET, HDPE, or PP; for heating scenarios, choose PP or specialized heat-resistant labels; and when recycling, follow local sorting guidelines. As a packaging manufacturer, Huashu Packaging fully considers the recyclability of materials and label standards during product design, helping brand clients meet increasingly strict environmental requirements. If you are planning your packaging solution, welcome to consult with us.Contact UsLet’s explore packaging solutions that balance safety, cost, and environmental protection. Learn more about industry insights by visitingOm Packaging Chinese Website。