Surface treatment – polyolefin films, such as polyethylene and polypropylene, have very low surface energy and therefore require surface modification in order to receive paints, adhesives, metallization and varnishes. This modification is done with corona, flame or plasma surface treatment.

The most common way of measuring this surface treatment is through solutions of ethylene glycol and formamide, and the unit of measurement is dina/cm. A value considered suitable for general applications is at least 38 dina/cm.