Developing device

Abstract

Abstract PURPOSE:To improve development quality by conveying and supplying magnetic single-component toner in a hopper to a developing roll by an electrostatic charging roll and applying a specific potential to between the rotary shafts of both rolls from a voltage source. CONSTITUTION:The developing roll 2 and electrostatic charging roll 3 rotate as shown by arrows and the toner 4 is scooped up in a laminar shape through the rotation of the electrostatic charging roll 3 and conveyed to the connection part for the developing roll 2, so that the toner 4 is charged electrostatically at the contacting part. Namely, the voltage E is applied from the voltage source 7 to between the rotary shafts 2a and 3a of both rolls 2 and 3. Further, the surface layer parts 2b and 3b of both rolls 2 and 3 are <=10<13>OMEGAcm in volume resistivity and lower in volume resistivity than toner 4 of <=10<14>OMEGAcm, so a potential difference is generated in the thickness direction of the layer of the toner 4 at the contacting part and charges are implanted into the toner 4 from the surface layer part 3b of the electrostatic charging roll 3, so that the toner 3 is charged electrostatically. Consequently, the developing roll need not be provided with projections and recesses, so superior development quality can be secured.

Inventors

• 👤 Katsuyuki Ito
• 👤 克之 伊藤
• 👤 Toshiro Murano
• 👤 敏郎 村野
• 👤 Yuhei Itasaka
• 👤 板坂　雄平
• 👤 Shigeki Nakajima
• 👤 茂喜 中嶋

Bibliographic Details