Patent ID: 6841327

Claim:
A developing assembly comprising: a developer container which holds therein a two-component developer comprising: a magnetic carrier; and a non-magnetic toner; and a developer-carrying member by which said two-component developer held in said developer container is transported to a developing zone facing an electrostatic-latent-image-bearing member, to render visible a latent image formed on the latent-image-bearing member, wherein said magnetic carrier has a weight-average particle diameter of from 15 μm to 60 μm, wherein said developer-carrying member comprises at least; a substrate; and a resin coat layer formed on the substrate surface, wherein said resin coat layer contains at least a binder resin and solid particles for forming an uneven resin coat layer surface having valleys and hills, wherein said solid particles have an average circularity of 0.64 or more, which is an average value of values calculated according to the following equation (1): Circularity=(4× A )/{( ML ) 2 ×Π (1), for each solid particle, wherein ML represents the Pythagorean-method maximum length of a particle projected image of one of said solid particles, and A represents a projected area of a particle image of one of said solid particles, and said resin coat layer fulfilling the following condition: S≧3.0, where, in a surface profile of the resin coat layer measured using a laser of a confocal optical system, the average value of heights from the bottoms of the valleys to the vertexes of the hills of the uneven resin coat layer surface in the whole measurement region is regarded as a standard height, and a proportion of surface area occupied by parts of hills more than 0.1×r higher than the standard height is represented by the percentage S, wherein r is the weight-average particle diameter, in units of μm, of said magnetic carrier; and wherein said resin coat layer further fulfills the following conditions: Rp/Rv≧ 1.2 , Rz/Rv≧ 2.0 and r/Rp≦ 6.0, where the ten-point average roughness of said resin coat layer surface is represented by Rz, in units of μm, the average-line depth of said resin coat layer surface is represented by Rp, in units of μm, and the average-line height of said resin coat layer surface is represented by Rv, in units of μm.