| abstract |
A developing roller comprising an axial core body, an elastic layer provided around the same and a surface layer containing a resin and resin particles provided around the elastic layer, wherein the surface layer has protrusions attributed to the resin particles and has a surface with a roughness of 0.15 to 0.70 roughness curve skewness (Rsk), and wherein the resin particles in a volume particle size distribution thereof have peak (P1) at particle diameter (d1), and wherein when a refers to the volume fraction of particles with diameter (d1) based on all resin particles and b and c respectively refer to the volume fractions of resin particles with diameters (d2 and d3), greater than (d1), based on all resin particles, these (d1), (d2), (d3), a, b and c satisfy a specified relationship. |