Soft film
Soft films or thin films are multilayer packaging films from which flexible packaging is made. The individual film layers are usually extruded . The film can be produced using the cast , blown or coextrusion process.
A soft or composite film consists of individual layers made of different types of polymer, such as polyamide (PA) or polyethylene (PE). Polyamide is necessary as an oxygen barrier and for shaping the film packaging. Polyethylene is necessary as a water vapor barrier, sealing layer and as a stabilizer for packaging. The layer structure of the flexible film must be adapted to the respective requirements. The ability of the flexible film to deep-draw depends primarily on the polyamide. Flexible films are used both as an upper film and as a lower film.
The packaging films are thermoformed - the process is also known as thermoforming or deep drawing. Flexible films have lost some of their importance compared to rigid films in recent years . The decisive factor was the better positioning of sliced goods on the self-service shelf thanks to rigid films compared to soft films. Nevertheless, flexible films or thin films are still authorized for vacuum-packed products such as B. vacuumed fresh meat.
Typical flexible film composites
- Multilayer films
- Polyamide / polyethylene
- Polyamide / surlyn
- Composite with ethylene vinyl alcohol
- Polypropylene / polyamide / polyethylene
- Polypropylene / polyethylene / polyamide / polyethylene
- Polypropylene / polyamide
- Polyethylene / polyamide / polyethylene