Twist-Off Caps: Characteristics, Fabrication and Applications

Introduction

Twist-off closures are a type of metal closure widely used in the packaging industry, especially on glass or plastic jars for food packaging. This article provides a detailed description of the characteristics, manufacturing process and applications of twist-off caps.

1. Characteristics of twist-off caps

Twist-off caps, also known as “White-Cap” or “Vapor Vacuum”, are metal caps with bayonet closure (¼ turn twist) or snap-on, screw-on or vertical push-on opening. These caps are made of tinplate and use sealing elements in the closure made from polyvinyl chloride resins.

2. Manufacturing process of twist-off lids

The manufacturing process of twist-off caps starts with the pressing of a capsule into the press with the general shape of the cap, the side wall of the cap being smooth and vertical. In this operation the central panel of the cover is profiled.

This is followed by the formation of the curl and the nails on the lid, which are key elements for the closing and opening of the jars. These elements allow the cap to fit properly on the bottle and ensure a tight seal.

Finally, the sealant is applied to the inside of the cap, which is a layer of polyvinyl chloride resin. This sealant ensures that the cap adheres properly to the bottle and provides a tight, secure seal.

3. Applications of twist-off caps

Twist-off closures are mainly used in the packaging industry to close glass or plastic jars for food packaging. Some of the most common applications include:

• Canned products: fruits, vegetables, fish, meats, etc.
• Jams, jellies and jams.
• Sauces and condiments.
• Beverages: juices, soft drinks, beers, etc.
• Dairy products: yogurts, desserts, etc.

Conclusion

Twist-off closures are an essential component in the packaging industry, especially for food packaging. Their characteristics, manufacturing process and applications make them a versatile and safe solution to guarantee the preservation and protection of packaged products.