Pressroom - Corona Treating

Corona treating increases the surface energy of plastic films, foils, and paper to improve wettability and adhesion of inks, coatings, and adhesives. Treating works best when a substrate is treated at the time of extrusion and in-line prior to converting. Proper corona treating provides increased press speeds, improved print quality, and less scrap.

Why do I need it?

Polymer films have chemically inert and non-porous surfaces with low surface tensions causing them to be non-receptive to bonding with substrates, printing inks, coatings, and adhesives.

Film that is not treated at the time of production will not accept printing, coating, or laminating well. Even if film is treated at the time of production, it will not always guarantee that printing, coating, or laminating we be easily accomplished at any future time.

Each film has an inherent surface energy (dyne level) that can be increased through corona treatment at the time of production. This level of treatment diminishes over time. So, film that can easily printed and coated immediately after production can, within a few days, lose sufficient enough surface energy to adversely affect optimum print or coating conditions. Also, in some films, additives can migrate to the surface over time. These surface imperfections can result in pinholing and other quality issues.

Since it is nearly impossible to always insure that the film you receive will be converted within the optimal time frame, retreating in-line is often a necessity. It's important to note that treating in-line cannot replace primary treatment at the time of production. In fact many films, especially polyolefins (Polyethylene and Polypropylene) are almost untreatable when they are set after production.

To ensure consistent quality and optimal print conditions, use films that have been treated at the time of production and re-treat in-line prior to converting if at all possible.

A good corona treatment system is designed to increase the surface energy of many substrates in order to allow improved wettability and adhesion of inks, coatings, and adhesives. As a result, the materials properly treated will demonstrate improved printing and coating quality, and stronger lamination strength.

For more information on this issue, please contact: info@teamflexo.com

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