Corona treaters pass film, foil or flat sheet under an electrode where a high-frequency discharge oxidizes the surface. It is the standard way to prepare polyolefin films for laminating adhesives, inks and coatings on converting lines. Like other treatments, the effect decays over time and with additives that migrate to the surface. Flame treatment does a similar job on molded 3D parts.
Corona treatment on the PE film is reading 38, laminator wants 42, turn up the watt density.
Also heard as
- corona
- corona discharge
Related terms
Plasma treatment
Exposing a surface to ionized gas to clean it and add reactive groups that raise its surface energy.
Surface energy
A measure of how strongly a solid surface attracts liquids, which decides whether an adhesive can wet it.
Dyne pen
A marker filled with test fluid of known surface tension, used to check a surface's treatment level.
LSE
Low surface energy, describing plastics and coatings that most adhesives cannot wet or bond without help.