Generation of a highly uniform and large area corona discharge source adaptable to surface treatment

We have developed an electrode system which consists of two equal shaped electrodes to produce a uniform distributed corona discharge. Each electrode has a lot of fine rods arranged with an equal distance on a flat plate (151.5×49.5 mm) which allows a surface treatment in a wide area. The corona discharges were initiated by a high frequency power supply of 350 W (15–30 kHz variable). Measurements of the uniformity of the corona have been made by the surface wettability of treated substrate surface by varying the product of the time of exposure and the input power. The wettability has been estimated by the reduction of the contact angle of water to the substrate. It has been postulated that the uniformity obtained was approximately 18.7% over the total length of the substrate (120 mm) using this electrode system.