Substrate Options —‘Paper or Plastic?’

Corona treatment changes the surface tension of plastic surfaces by subjecting them to a high voltage discharge, rendering them more ink- receptive. Surface energy is measured in dynes. Because the effects of corona treatment tend to dissipate over time, it's best to use a shipment of plastic as soon as it is received. In cases where the plastic cannot be used right away, however, printers will sometimes re-corona treat the substrate to reinvigorate or change its surface energy. This can be done by installing a corona treater in-line on a web press just before printing, or by affixing it to the first printing unit, such that every piece of plastic printed would receive corona treatment before passing through the remaining units for printing.