| 摘要 |
PURPOSE:To secure the degree of freedom for the scattering of toner particles in a development area and to prevent a decrease in concentration by allowing the toner particles to receive attractive force against contacting pressure to magnetic particles. CONSTITUTION:When development is carried out under such conditions that the potential of an electrostatic latent image on an image carrier is, for example, 200-600V, the gap of the development area 5 is 300mum, and the development speed is 270mm/sec, a developer 4 whose layer thickness is uniformed by a leveling member 9 is excited with a bias voltage 11 applied to the leveling member 9. This bias voltage 11 is a DC voltage having the opposite polarity from toner particles, so the degree of freedom of the toner particles is secured because of the attractive force operating against the contact pressure to the magnetic particles which is received from the leveling member 9. The toner particles are therefore scattered actively without decreasing in its flowability, so the concentration in the development area 5 is prevented from decreasing. |
