抄録
This study investigates a bead-carry-out (BCO) phenomenon in a two-component magnetic development system used for a color laser printer. It has been clarified by the experiment that the electrical conductivity of carrier beads and toner concentration are highly related to the critical pull-off field of the BCO. Based on this experimental evidence, a numerical calculation has been conducted on the electrical charge of a carrier chain in the electrostatic filed by the finite element method to deduce a critical force that the BCO takes place. It has been clarified by the experiment and the calculation that toner particles prohibit the electrical conduction of the chain and hence the charge is diluted in the chain over the critical concentration of toner particles in the chain. This results in the reduction of Coulomb force applied to the top of the chain and improves the BCO.
