Patent ID: 7869739

Claim:
A xerographic marking device, comprising: an intermediate transfer unit; and at least one two-color image-on-image (IOI) drum module, each two-color IOI drum module including a) a first charging unit disposed along a rotatable photoconductive photoreceptor, wherein the first charging unit places a substantially uniform charge on the photoreceptor; b) a first exposure unit disposed along the photoreceptor downstream of the first charging unit, wherein the first exposure unit performs an image-wise exposure to the photoreceptor to produce a first latent electrostatic image on the photoreceptor; c) a first development unit disposed along the photoreceptor downstream of the first exposure unit, wherein the first development unit places a first marking material on the photoreceptor according to the first latent electrostatic image to produce a first toned image; d) a second charging unit disposed on the photoreceptor downstream of the first exposure unit, wherein the second charging unit places a substantially uniform charge on the photoreceptor; e) a second exposure unit disposed along the photoreceptor downstream of the second charging unit, wherein the second exposure unit performs an image-wise exposure to the photoreceptor to produce a second latent electrostatic image on the photoreceptor; and f) a second development unit disposed along the photoreceptor downstream of the second exposure unit, wherein the second development unit places a second marking material on the photoreceptor according to the second latent electrostatic image to produce a second toned image, wherein the intermediate transfer unit receives the first toned image and the second toned image from the photoreceptor in a single transfer, and transfers those toner images to print media to produce a toned image on print media.