Surface modifying device

A surface modifying device, comprising a discharge electrode that is placed in an electrode chamber and has a length equal to or longer than a width of a treatment base material, and a treatment roller that transfers the treatment base material, the discharge electrode facing the treatment base material, a discharge being produced between the discharge electrode and the treatment roller, wherein

• the discharge electrode includes a pair of electrode members each of which has a length approximately matching to the width of the treatment base material,
• the electrode members face each other across a support member that is placed between them, the support member having a length approximately equal to the length of the electrode members,
• an interstice is formed in the face-to-face area between the electrode members to serve as a gas passage,
• the gas passage has a distal end opening to a face-to-face area between the discharge electrode and the treatment roller,
• the support member has a plurality of gas guide holes formed therein in a longitudinal direction of the support member, the plurality of gas guide holes communicates with a replacement-gas feeding system, and
• the gas guide holes communicate with the gas passage.