The composition and structure of the bottle cap and the important role played by each part.

The bottle cap is an important part of mineral water packaging. It plays a key role in ensuring sealing and safety.

1. Functional stripes (anti-slip/friction enhancement)
There is a circle of concave and convex stripes around the bottle cap to prevent slipping. By increasing the roughness of the contact surface, the friction is increased. It is convenient for users to open or close the bottle cap. Especially when the hands are stained with liquid, the stripe design can provide better grip.

2. Sealing structure (thread and sealing ring)
The thread inside the bottle cap matches the thread at the bottle mouth. The threads are engaged with each other by rotation to form a firm seal. Such a structure can effectively prevent gas or liquid from entering the bottle. This is especially important for water and beverage products that need to avoid external influences. Another important part inside is the sealing ring. It is a thin ring-shaped plastic sheet. When the bottle cap is closed, the sealing ring is tightly attached to the edge of the inside of the bottle mouth, forming a reliable leak-proof barrier. It also prevents odors or contaminants from entering the bottle, thereby ensuring the freshness of the contents.

3. Anti-theft ring
The anti-theft ring is usually formed integrally with the bottle cap. It is connected to the bottle cap through fine teeth, buckles or score lines. When the cap is opened, the shear force generated by the selection or pulling causes the anti-theft ring to break and remain on the bottle mouth. This design ensures that once the bottle cap is opened, the anti-theft ring will fall off. Users can use this detail to determine whether the beverage has been opened, so as to avoid drinking opened beverages and ensure the hygiene and safety of the beverage.