What is corona therapy?
Corona treatment is used to increase the surface energy of plastics and other materials to improve the adhesion of inks, adhesives and coatings. Corona treated material has higher print and coating quality than uncorona treated material.
Since polymers and many other substrates are non-porous, they do not absorb inks, paints and adhesives. Instead, the media sits on the surface without being bonded to it. By increasing the surface tension through microscopic chemical changes in the plastic material, the ink or glue now has something to "stick to."
Corona surface treatment can be applied to a variety of materials including but not limited to:
polymers such as:
Polypropylene
polyethylene
polystyrene
elastomer
pet
pvc
Vinyl
Silicone Rubber
other materials such as:
Foam
foil
aluminum
metallized surface
Glass
composite material
Paper
To treat this material, it is placed under a cloud of corona discharge, which is created by exposing the atmosphere to different voltage potentials. The electrons hold three times more energy than is required to break molecular bonds on the surface, and the free radicals quickly begin to oxidize the material in the cloud. The result is increased surface tension, allowing wetting and adhesion.
Benefits of Corona Therapy
In addition to improving the adhesion of coatings, inks and adhesives, corona treatment offers a wide range of benefits, including:
reduce waste. If the bonding process fails, the material will need to be discarded. Preparing the surface ensures that your paint, coating or glue will stick the first time, so you don't have any failed attempts that result in wasted time and materials.
Eliminate migratory additives. Many materials contain additives to enhance specific qualities of the material. Over time, these additives may migrate to the surface, and if they remain on the surface, the ink will bind to the additives rather than the material itself. Corona treatment removes any additives that float to the surface.
Reduces rotting surfaces. Embossing can be used to restore the surface tension of old pre-treated materials. This means you don't have to worry about surface rot on materials that have been in storage for long periods of time. Simply by bumping, you can restore the surface to its pre-treatment adhesion potential.
Clean your material. Dust and debris can hinder adhesion. Because the plasma treatment prepares the surface for bonding, it also removes dirt that could prevent a successful bond.
