Abstract: A developing agent comprising toner particles and carrier particles, the toner particles including less than 21% of particles having a roundness of less than 0.93, and containing a binder resin, a coloring agent, and an charge controlling agent free from heavy metals.

Abstract: A developing device is provided with: a photosensitive body; a developing roller for performing an electro-photography on the photosensitive body at a predetermined developing position of the photosensitive body by using charged toners; a moving device for moving the developing roller and the photosensitive body such that the developing roller performs the electro-photography on the photosensitive body at the developing position and that, after the electro-photography is performed, the photosensitive body transports the toners, which have never been used for the electro-photography and remain on the photosensitive body, to the developing position where the transported toners adhere from the photosensitive body onto the developing roller so as to recover the transported toners from the photosensitive body onto the developing roller; and a collecting device opposed to the developing roller for collecting impurities mixed in the recovered toners on the developing roller by contacting with the developing roller.

Abstract: An apparatus for reducing electrostatic charge of particles in a waste container. In one embodiment the waste container is coated with a liquid having a viscosity sufficient to prevent tribocharging between the waste container and the waster toner particles, and to collect toner particles deposited from the cyclone separator into the waste container. Another embodiment describes the use of a flange extending into the waste container to prevent tribocharging that can cause explosions in the waste toner bottle.

Abstract: A printing machine for creating an image through the use of toner particles. the printing machine having a development device for preparing the toner, and the development device having at least one filter for selecting toner particles.

Abstract: An image forming apparatus of the present invention includes a developing device for forming a developed image by transferring a developing agent to an electrostatic latent image formed on a photosensitive drum, a developing agent recycling mechanism for returning the developing agent recovered from the photosensitive drum by a cleaning device to the developing device after transferring the developed image formed on the photosensitive drum on a sheet paper, and a contact member for adsorbing impurities contained in the developing agent returned by the recycling mechanism by an adsorbing voltage having a voltage and polarity defined based on the charged polarity of the developing agent and the developing bias voltage applied to the developing roller and the developing agent of the developing device.

Abstract: An electrostatographic reproduction machine that includes an image bearing member means for forming a latent image having image areas and background areas; at least a development housing containing charged carrier beads, charged fragments of the charged carrier beads which undesirably cause image deletions, and charged toner particles for developing image areas to form a toner image; means for transferring the toner image to a sheet of paper, and means for fusing the toner image to the sheet of paper. Importantly the reproduction machine includes a method and control system for reducing halftone image deletions in future halftone images.

Abstract: A toner replenishing method for use in a development process of developing latent electrostatic images formed on an electrophotographic photoconductor with a two-component dry developer containing a toner and a carrier, the latent electrostatic images being formed on the electrophotographic photoconductor by uniformly charging the electrophotographic photoconductor to a predetermined potential and exposing the electrically charged photoconductor to light images corresponding to original images, includes the step of replenishing the toner only in a portion of the two-component dry developer as the toner concentration thereof is decreased so as to make up for the used toner in the course of the development of the latent electrostatic images.

Abstract: An apparatus for filtering contaminants from marking particles is provided. The apparatus includes a conduit and a mover for moving the marking particles within the conduit. The apparatus also includes a screen positioned adjacent the conduit so that substantially all the marking particles discharged from the conduit pass through the screen.

Abstract: A developing unit using a bicomponent developer and capable of collecting only carrier included in the developer and deteriorated due to aging while recycling toner, and a method of collecting the developer from the developing unit. The developing unit separate the developer into toner and carrier before the collection of the developer.