| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a scorotron charging device that realizes high speed printing, high picture quality, and an enhanced life while making a diameter of wire as small as possible. <P>SOLUTION: An electric discharge wire 27 of a scorotron charging device includes a base material 27a made of tungsten and a gold plated layer 27b applied to the surface of the base material 27a. An electric resistance value per unit length of a longitudinal direction of the gold plated layer 27b is made to the resistance value per unit length of the base material 27a, or less. When the electric resistivity of the base material 27a is taken as Rw, the cross-section of the base material 27a as Sw, the electric resistivity of the plated layer 27b as Rc, and the cross-section of a coat layer 27b as Sc, a formula [Rc/Sc≤Rw/Sw] is established. The base material 27a can be prevented from being degraded to become thin due to a large load that is caused by a much more current that flows into the coat layer 27b. <P>COPYRIGHT: (C)2013,JPO&INPIT |
