Process cartridge and electrophotographic apparatus

A process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge comprising:

• an electrophotographic photosensitive member;
• and
• a charging member,
• wherein the electrophotographic photosensitive member comprises a first support and a photosensitive layer,
• when an electric current is measured which flows when a voltage is applied to a surface of the electrophotographic photosensitive member while being varied, there exists a point at which gradients change, in a graph in which a horizontal axis is a square root of an electric field strength E [V/m] in the photosensitive layer, and a vertical axis is a common logarithm of the electric current, and
• when a gradient of the graph is represented by a1, in a region in which the electric field strength is smaller than that of the point at which the gradients change, and a gradient of the graph is represented by a2, in a region in which the electric field strength is larger than that of the point at which the gradients change, a2/a1 is 1.50 or larger;
• and
• the charging member comprises a second support having an electroconductive outer surface, and a second electroconductive layer provided on the outer surface of the second support, wherein
• the second electroconductive layer comprises a matrix containing a first rubber, and a plurality of domains that are dispersed in the matrix, wherein
• the domain comprises a second rubber and an electron conducting agent,
• at least a portion of the domain is exposed to an outer surface of the charging member, and
• the outer surface of the charging member comprises at least the matrix and at least a portion of the domain, wherein
• when a volume resistivity of the matrix is represented by ρM [Ω·cm] and a volume resistivity of the domain is represented by ρD [Ω·cm], ρM is 1.0×105 times or higher of ρD.