Characteristics of an atmospheric pressure low temperature discharge produced for 3-d surface treatments

Summary form only given. A volumetric plasma was produced at the atmospheric pressure using a low frequency power supply. Two parallel electrical wires were placed at the inner surface of the cylindrical dielectric tube. The tube diameter and length were 30 mm and 80 mm, respectively. A helium gas was supplied for stable plasma generation. Based on the electrical and optical diagnostics, the plasma properties were studied. The plasma was produced at a peak to peak voltage of about 1000 V and filled the whole surface of the dielectric tube along the wires. The plasma current of 10 mA and the gas temperature of 350 K made the plasma surface treatment of thermally sensitive material possible. Some 3-dimensional shape materials of aluminum, Teflon, paper, and polymers were treated by the plasma. Using the contact angle method, it was shown that the plasma treatment enhanced the surface wettability. Sealing up the active discharge region enhanced the surface treatment effect