Electrophotographic photoconductor and image-forming apparatus including the same

An electrophotographic photoconductor comprising:

• a photoconductive layer, comprising at least a charge generation layer and a charge transport layer serially stacked, the photoconductive layer provided on an electrically-conductive base,
• wherein an outermost surface layer of the electrophotographic photoconductor comprises silica microparticles,
• wherein the silica microparticles have a number mean primary particle diameter of 10-40 nm,
• wherein the silica microparticles are added to a glass container along with at least a charge transport substance, a binder resin, and a solvent, and are mixed and stirred in the glass container and then are dispersed uniformly into the outermost surface layer at a proportion of 7-18% by mass in the outermost surface layer,
• wherein, in slicing the outermost surface layer in a stacking direction of the outermost surface layer with a thickness of 70 nm, a strip-shaped sample piece thus obtained is observed under a scanning transmission electron microscope, a cross-sectional image thus obtained is converted to an 8-bit binary image, any 50 regions from regions having a 5 μm×5 μm observation field of view in the 8-bit binary image thus obtained is observed, and a relationship represented by the following formula is met:
• 0.5≤SAve/N≤2.0
• wherein SAve is a mean value of the 50 regions for a proportion (%) of an occupied area of the silica microparticles to an area of an observation region (S) being 25 μm2, and N is a total solid content (g) in the outermost surface layer, and
• wherein a maximum gap region has a size of 1.0 μm or less when represents a space with absence of the silica microparticles converted to an equivalent circle diameter.