With film usage expected to rise in the future, label and package printers will continue to benefit from corona treaters. According to TLMI, 75% of pressure sensitive labels are printed on paper, but the usage among all formats – including flexible packaging, shrink sleeves, etc. – is nearly split. Currently, films are seeing high single-digit growth.

The proliferation of filmic substrates will only enhance the need for corona treatment. Corona treaters have been optimized to modify surface energy, improving the wettability and adhesion of inks, coatings and adhesives. Unsupported filmic materials are inherently non-absorbent, making them the best candidate for corona treating.

Corotec, a manufacturer of corona treating equipment for conductive and non-conductive materials, offers a broad product portfolio design to enhance this critical market. Corotec provides multiple designs to meet the needs of label converters.

“We offer conventional covered roll corona treatment and bare roll corona treatment, both in a single corona system called our Uni-Dyne system,” explains Bill Campbell, Corotec's Western regional sales manager. “The system enables effective treatment of a wide variety of materials at high press speeds with the simple turn of a switch between treatment electrodes.”

Corotec also builds sheet treating systems for non-web label applications, along with special design wide web press corona treatment systems. To capture the growth for short-run printing, Corotec constructs systems for digital printing and finishing equipment.

Oftentimes, films are utilized for brands that want to give a more luxurious look and feel on the shelf. Printers, therefore, need to ensure they’re properly treating the materials to give them that wow factor in the store.

“Depending on the label material and chemistries involved, corona treatment is often the difference between a successful label job and no job at all,” says Campbell. “Corona treatment helps anchor the wide variety of inks, coatings and over-laminated films used in label printing to the various substrates used. It also must do so at faster and faster press speeds to keep profitability in the label run.”

When a label undergoes corona treatment, it delivers a higher quality label, where the label chemistries have a greater bond to the substrate on which they are printed. “Films by nature are low surface energy/hydrophobic substrates that water-based/UV chemistries do not naturally want to bond to,” notes Campbell. “Corona treatment enhances the bonding of these chemistries by creating a higher surface energy/more hydrophilic surface for inks and coatings to bond to. Corona treatment also enhances printing dot gain quality, along with faster dry and cure times on press.”

Corotec’s latest system designs are designed to meet the ever-increasing need for higher and more consistent dyne levels on a range of new laminates, metalized materials, and for those using UV-curable or water-based inks and adhesives.

“Press speeds keep getting faster, requiring greater power in the corona treatment process,” says Campbell. “Building corona systems to enable the presses to run at maximum capacity requires re-thinking designs all the time. Many design options are now available from Corotec, depending upon our customer specific applications. Process automation is certainly evolving, with ease of integration and HMI controls – among other options – available. New materials and chemistries are evolving and continually being tested for corona treatment. Digital printing and specialized finishing equipment also has corona treatment needs.”

In addition, the company is also offering a trial program that allows customers to find the right product for their specific application. There is also a rental system in place, allowing users to experiment with equipment, and following the rental period, purchase for a reduced price.