HeFeng has provided innovative surface treatment solutions for a multitude of industry sectors with its plasma and corona treatment technologies. Our surface treatment solutions are flexible to meet the demands of materials like metal, plastic or glass, working environments and industries.
Corona treatment is a very effective way to increase the surface tension of various materials. By treating the material with high frequency and high voltage corona discharge, the surface of a substrate is given with adhesive properties so that it becomes more impressible to inks, coatings and adhesives.
Corona treatment, is known as dielectric barrier discharge (DBD), mainly used for surface treatment of plastic films and sheets. Before a substrate to be processed with ink printing, laminating, blown film / cast film extrusion, coating, gluing, modification and polymerization, corona treatment should be applied to increase the bonding characteristics of the substrate (increasing the dyne level).
Plasma is often referred to as the forth state of matter. It is based on the physical principle that by adding energy to matter so that solid becomes liquid, and the liquid becomes gaseous. If we continue to supply enough energy to the gas, the gas molecules will be ionized and generates the plasma. Atmospheric plasma and vacuum plasma are the two primary categories. The atmospheric air plasma treater utilizes blown ion or blown arc plasma technologies.
Optimal corona discharge air gap of 1-1.5 mm
Before applying corona treatment or plasma treatment, the surface tension of the material has to be tested to determine whether the material being processed needs surface treatment or not. Dyne pen, or corona test pen, is a common test method.
Using dyne pen to simply draw a line over the surface of the material to be tested, if the line is solid and does not shrink, that means you have achieved correct dyne level. If the line shrinks and breaks into droplets within 2 seconds then the dyne level is incorrect. The actual surface tension of material surface can be measured by applying dyne pens of different values.
High contact angle
Poor printing effect
Low contact angle
Good printing effect