PURPOSE: To obtain a multicolored image at a high speed and with good gradation with one time of electrostatic charging and exposing by forming plural layers of materials exhibiting light absorptivity and photoconductivity in a narrow light wavelength range on a substrate and sticking toner particles thereon according to the potential distribution of electrostatic latent images.
CONSTITUTION: A photoreceptor is manufactured by forming plural layers of materials exhibiting light absorptivity and photoconductivity in a narrow wavelength region on, for example, a conductive substrate 4; for example, by forming a charge transfer layer 1 exhibiting light absorptivity and photoconductivity at wavelength at A3≤λ<A2, a charge transfer layer 2 exhibiting light absorptivity and photoconductivity at λ3≤λ<λ1, and a charge generation layer 1 exhibiting light absorptivity and photoconductivity at λ3≤λ<λ0 in the case of forming two color latent images. If such photoreceptor is electrostatically charged and exposed, differences arise in the surface potentials of the photoreceptor according to the characteristics of the respective layers. The surface potentials are then developed by using two specific toner boxes 81 which bias the toners of reversed polarities differing in colors according to the respective surface potentials. The development of two colors is thus made possible by one time of electrostatic charging and exposing. An image of more than three colors is similarly obtd.
ARISHIMA KOUICHI
MATSUURA TAKETOSHI
OKADA TAKESHI
