Patent ID: 8369754

Claim:
A developing device, comprising: a storage section for storing a two-component developer containing non-magnetic toner and magnetic carrier, wherein toner is charged to a first polarity, and carrier is charged to a second polarity that is opposite to the first polarity; a first development roller which includes a rotating sleeve and therein a fixed magnetic pole, and is configured to carry, on a circumferential surface of the sleeve, the two-component developer stored in the storage section, and configured to develop in a first development area an electrostatic latent image formed on an image carrier, with the carried two-component developer, wherein a first development bias is applied to the first development roller; a layer thickness regulating section for regulating at a regulation position an amount of the two-component developer carried on the circumferential surface of the sleeve; and a second development roller made of a non-magnetic material, and configured to carry on a circumferential surface thereof toner supplied from the first development roller, and to develop the electrostatic latent image on the image carrier, in a second development area which is on a downstream side from the first development area in a rotating direction of the image carrier, wherein a second development bias is applied to the second development roller, wherein the circumferential surface of the sleeve and a surface of the image carrier move in different linear directions from each other in the first development area, a supply position at which the first development roller supplies the toner to the second development roller is located on a downstream side from the regulation position and on an upstream side of the first development area in a rotating direction of the first development roller, and the first development bias and the second development bias form an electric field between the first development roller and the second development roller which attracts and transfers the non-magnetic toner from the first development roller to the second development roller while the magnetic carrier remains on the first development roller.