GRANULAR ELECTROSTATIC CHARGING AGENT, ELECTROSTATIC CHARGING AND IMAGE FORMING METHOD

摘要

PURPOSE: To uniformly electrostatically charge a photosensitive body, etc., without generating ozone by disposing a conductive part and high resistivity part in the granular electrostatic charging agent and controlling the average grain size and specific volume resistivity thereof. ;CONSTITUTION: This granular electrostatic charging agent is composed of conductive magnetic particles having conductive magnetic surfaces and high-resistance magnetic particles having particle surfaces of high resistance in the case of two components granular electrostatic charging agent. These conductive magnetic particles have the specific volume resistivity of ≤10⁶Ω.cm. On the other hand, the high-resistance magnetic particles have the specific volume resistivity of ≥10⁶Ω.cm. The average grain sizes of both particles are ≤60μm. The average grain size of the high-resistance magnetic particles is 20 to 60μm and is preferably set larger than the average grain size of the conductive magnetic particles. As a result, the effect of preventing carrier attraction is improved. In addition, the electrostatic charge contact surface with the photosensitive body is increased and the electrostatic charge applying power is improved.;COPYRIGHT: (C)1995,JPO