Rigid foil
Rigid films or thick films are packaging films from which stable or hard shells (hard shell packs ) are made. Mono films or high-quality composite films can be used for this . Composite films offer several advantages such as simple sealing or welding to the upper film.
The structure of a rigid film or composite film consists of a carrier film, which is extruded or calendered , and of a sealing film or also called a sealing layer. The carrier film is the film layer that makes the hard box stable and stable. The composite film can be equipped with an additional barrier layer if the carrier film should not already have sufficient inherent barrier. The additional barrier layer can then be introduced into the sealing film. Usually, ethylene vinyl alcohol (EVOH) - embedded in polyethylene (PE) - is used for this.
The packaging films are thermoformed . Rigid films, in particular rigid film packaging (blisters), have become increasingly important in recent years. The decisive factor was especially compared to the flexible film better positioning of sliced goods in SB -Regal.
Typical rigid film composites
- A- polyethylene terephthalate / polyethylene
- A-polyethylene terephthalate / polyethylene-ethylene vinyl alcohol-polyethylene
- Polystyrene / polyethylene
- Polypropylene / polyethylene
- Polypropylene-polyethylene-ethylene vinyl alcohol-polyethylene
- Polyvinyl chloride / polyethylene
- Polyvinyl chloride / polyethylene-ethylene vinyl alcohol-polyethylene