Current Raw Materials
Surprisingly there are few raw material types currently available for flexible packaging. Paper, PET, aluminium, PE and OPP cover over 90% of all applications. However, there are numerous designs, formulations, thicknesses, etc. for each raw material type. For instance, OPP has hundreds of variations in formulation available in the market.
Raw Material Abbreviations
| Abbreviation | Description |
|---|---|
| Alu | Aluminium foil |
| BOPP | Biaxially orientated polypropylene, often used instead of OPP. |
| CPP | Cast polypropylene, made using film extrusion rather than blowing. Often used as heat-sealable coatings. |
| HDPE | High-density polyethylene |
| LDPE | Low-density polyethylene (PE). PE with lower density than other PE types. The most frequently used PE. |
| LLDPE | Linear low-density polyethylene. Often mixed with LDPE, to achieve a better hot-tack in sealing. |
| Metallisation | Wafer-thin layer of vapour-deposited aluminium, which can significantly improve the barrier properties of Polyester (PET) or Orientated polypropylene (OPP). |
| Metallocene | Term usually associated with polyethylene (PE) where polymerisation is controlled by catalysts in relation to specific requirements (Metallocene is the catalyst). |
| OPP | Orientated polypropylene: usually in both directions (machine direction and perpendicular to machine direction), therefore also known as BOPP (biaxially orientated polypropylene). |
| PA | Polyamide, or nylon, has excellent gas barriers and is more flexible than polyester (PET). |
| PE | Polyethylene, a term for all polyethylene types. |
| PET | Polyester film, highly suitable as the outer layer for various compounds. |
Current Raw Materials and Their Use
| Raw Material Family |
Most Frequently User For |
Typical Application |
|---|---|---|
| Paper | Substrate in a compound (usually Paper / Alu / PE) | Soup Container |
| PET | Substrate in a compound (usually printed on the inside facing layer to protect the print). | Coffee Container |
| Alu | Barrier layer (100% leak-proof) | Various Containers |
| PE | Heat-sealable coating (inside) | Various Containers |
| OPP | Mono-material or in OPP / OPP compound | Chocolate Bars |