Generally speaking, it is divided into PP and PE.
PP material: It is mostly used for gas beverage bottle cap gasket and bottle cap. It has no heat deformation, high surface strength and good chemical stability. The disadvantage is poor toughness, easy embrittlement under low temperature conditions, and poor oxidation resistance. Wear resistant. This type of bottle cap is mostly used for fruit wine and carbonated beverage bottle cap packaging.
PE materials: mostly used for hot filling caps and aseptic cold-filled caps. This material is non-toxic, has good toughness and impact resistance, is also easy to form film, is resistant to high and low temperature, and has environmental stress cracking performance. Good, the disadvantage is that the molding shrinkage is large and the deformation is severe. Many vegetable oils on the market, sesame oil in glass bottles, etc. are mostly such materials.
Plastic bottle caps are generally divided into gasket type and inner plug type.
The production process is divided into compression molding and injection molding.
The size is mostly: 28mm, 30mm, 38mm, 44mm, 48mmand so on. The number of teeth is divided into: multiples of 9 and 12. The anti-theft ring is divided into 8 buttons and 12 buttons. The structure is mostly: separate connection (also called bridge type) and one-shot type. Uses are generally divided into: gas caps, heat-resistant caps and sterile caps.