The treater roll acts as the electric counter electrode in most corona treatment station designs. The treater roll and the dielectric material installed on its surface have a major effect on the formation and the quality of the plasma discharge and thus the overall efficiency of the treatment process. A treater roll is always selected specifically for the individual application. The type of corona electrodes to be used and the properties of the material to be treated are important factors in this decision.
In addition to the treater rolls that are delivered as part of our corona systems, SOFTAL offers customers the opportunity to send in treater rolls for renewal of damaged coatings or repair of damaged roll journals. Of course, complete roll assemblies are also available as a spare part from SOFTAL.
Stainless steel rolls
When a stainless steel treater roll is used, the dielectric is part of the corona electrode. This means that, in most cases, stainless steel rolls are combined with ceramic electrodes. Stainless steel treater rolls are coated with conductive layers for corrosion protection.
Silicone coated rolls
Silicone is the most commonly used coating material for treater rolls. The silicone coating acts as a dielectric and allows the use of inexpensive steel electrodes, provided that the material to be treated is suitable for this combination. Minor defects in a silicone coating can be repaired without removal of the treater roll from the treatment station. Heavily damaged silicone coats are quickly, easily and inexpensively replaced.
Ceramic coated rolls
Rolls with a ceramic coat are used in special applications with conductive webs. Ceramic coated rolls are manufactured in an elaborate plasma coating process which places them in a higher price segment than uncoated or silocone coated rollers.
The ceramic coat is hard enough to resist any mechanical stress that is likely to occur during normal operation. The ceramic coat also acts as a dielectric.