Experimental and numerical investigations have been carried out on the bead-carry-out phenomenon of electromagnetic bead chains in two component development process of electrophotography. Electrostatic pull-off characteristics of chains were measured in a magnetic field and then it was clarified how the critical electrostatic pull-off field to break chains and the amount of pulled-off carriers depended on the bead diameter and the magnetic field. Magnetic bonding force and electrostatic pull-off force were estimated numerically to evaluate these experimental results. It was deduced that the bead-carry-out phenomenon could be predicted qualitatively from the comparison of calculated magnetic and electrostatic force.
Nobuyuki Nakayama, Yoichi Watanabe, Yasuaki Watanabe, Hiroyuki Kawamoto, "Experimental and Numerical Study on the Bead-Carry-Out in Two Component Development Process in Electrophotography" in Journal of Imaging Science and Technology, 2005, pp 539 - 544, https://doi.org/10.2352/J.ImagingSci.Technol.2005.49.5.art00012