Atmospheric pressure plasma with a flat spiral electrode

A new kind of electrically isolated flat spiral electrode for generating homogeneous atmospheric pressure plasmas is proposed. A sinusoidal voltage (5 kVpk–pk, 48 kHz) has been applied to the electrode. The high voltage is generated with a dc supply voltage of only 4 V, based on the electrical characteristics of a resonant circuit. Plasma was generated in closed spaces in helium with air impurities, with or without using a second grounded electrode. The gas temperature was of around 324 K and the plasma was tested for the paperboard hydrophilicity and transparent film for printer wettability modifications.