Process types of shrink film

Shrink filmscome in a variety of process types, including Single Wound shrink film, center folded shrink film, corona film, and edge-sealed shrink film. Shrink film products with different production processes can meet diverse packaging needs. But which type is more suitable for your product? Below, we explore these shrink films of different process types, their unique characteristics, and how to select the right one.

Single Wound Shrink Film

Single Wound Shrink Film is produced directly through plasticizing process extrusion of blow molding machine, making it the most basic yet performance-demanding type of shrink film.

It is suitable for products with fixed dimensions and excels in packaging efficiency, capable of sealing 120–140 products per minute. However, such high-speed packaging also requires more advanced machinery. If your production prioritizes equipment compatibility and efficiency, single wound shrink film is an excellent choice.

Enter Folded Shrink Film

Center Folded Shrink Film is created by fold a single-layer film along its centerline, forming a double-layer structure. It requires sealing and cutting before shrinking.

Its key advantage lies in adjustability—by modifying the fold width, it can compatible with products of varying diameters, offering greater flexibility. As a result, center folded shrink film is a popular option for many manufacturers.

Corona Film

Corona Film is a film with special surface treatment. Its treatment method is to produce microscopic roughness on the film’s surface through high-voltage corona discharge, enhancing ink adhesion.

This makes it particularly suitable for printed packaging applications. For instance, in food labels, pharmaceutical packaging, and other scenarios demanding printing quality, corona film ensures long-lasting, sharp graphics, providing reliable packaging performance.

Edge-sealed Shrink Film

Edge-sealed shrink film is an upgraded version of center folded shrink film, where one edge is thermally sealed into a tubular structure for a more robust closure.

Regular films are usually formed by folding, which can result in fragile edges. For irregularly shaped products, this may lead to inconsistent seal lines, affecting aesthetics or even splitting. Edge-sealed shrink film significantly strengthens the edges. At the same time, Its sealing performance is better than that of regular center folding shrink film, which can better prevent moisture and dust.  

In practical applications, edge-sealed shrink film has clear advantages. Center folded shrink film requires additional sealing and cutting during use, often producing thicker, less attractive seal lines. In contrast, heat-sealed edge film is ready to use, delivering finer, more aesthetically pleasing seals. When packaging demands high strength and reliable sealing, edge-sealed shrink film is the better choice.

Different shrink film of process types offer distinct advantages. The optimal selection depends on product specifications, packaging requirements, and production efficiency. By evaluating these factors, you can determine the most suitable type for your needs.