A corona discharge is the plasma curtain that is created when air around a conductor gets ionized. Corona discharges
are usually a glowing purple veil that is used to alter the adhesion properties of surfaces. They are created by applying a high voltage to small electrode tips. When a surface undergoes corona treatment, it passes under a corona discharge
. This causes surface activation
of the material by bombarding it with plasma ions. Surfaces that go through corona adhesion treatments enhance their adhesion capabilities. Corona discharges
are also used to reduce drag on a flat surfaces, sanitize pool water, remove unwanted volatile organics including pesticides and chemical agents from the air.