Change in charging characteristics of polyethylene surface by corona treatments and its dependence on humidity

摘要

The charging characteristics of polyethylene film can be changed by corona-treatment, and the change depends on the amount of electric power. However, in order to carry out the corona-treatment in the atmosphere, we have to consider the influence of humidity. In the present experiment, the charging characteristics of sample films were measured at constant corona power in various humidity of atmosphere. The amount of change generated by contact and friction with copper beads increased in negative polarity with the increase in humidity. When the relative humidity differs, we have to change the applied voltage to keep the electric power constant. The change in the applied voltage results in the change in the ion velocity. Then, the mechanism of the change in charging characteristics of films treated in various humidity was investigated from the viewpoint of the kinetic energy of ion.