Electroconductive member, process cartridge, and electrophotographic image forming apparatus

A process for producing an electrophotographic electroconductive member, comprising:

• an electroconductive support;
• and
• an electroconductive layer in order, the electroconductive layer having a matrix including a crosslinked product of a first rubber, and domains including a crosslinked product of a second rubber and an electroconductive particle, wherein
• an impedance is 1.0×103 to 1.0×108Ω when a platinum electrode is provided directly on an outer surface of the electroconductive member, and an alternating voltage is applied between an outer surface of the electroconductive support and the platinum electrode at an amplitude of 1 V and a frequency of 1.0 Hz under an environment of a temperature of 23° C. and a relative humidity of 50%, and
• when defining a length of the electroconductive layer in a longitudinal direction as L and defining a thickness of the electroconductive layer as T, and assuming that a 15-μm square observation region is put at arbitrary three positions in a thickness region from an outer surface of the electroconductive layer to a depth of 0.1T to 0.9T on each of cross sections in a thickness direction of the electroconductive layer at three positions:
• a center of the electroconductive layer in the longitudinal direction and points from both edges of the electroconductive layer toward the center by L/4, among the domains observed in each of the observation regions areas whose total number of nine, 80% by number or more of the domains satisfy (1) and (2):
• (1) a ratio of a cross-sectional area of the electroconductive particle included in a domain to a cross-sectional area of the domain is 20% or more;
• and
• (2) AB is 1.00 to 1.10 when A is a peripheral length of a domain and B is an envelope perimeter of the domain, the process comprising the steps of:
• providing a rubber mixture for forming the domain, including carbon black and the second rubber by kneading the carbon black and the second rubber (PG0044, 0078);
• proving a rubber mixture for forming the matrix, including the first rubber (PG0044);
• kneading the rubber mixture for forming the domain and the rubber mixture for forming the matrix to prepare a rubber composition having a matrix-domain structure (PG 0044);
• forming a layer of the rubber composition on a surface of the electroconductive support (PG0044);
• and
• curing the layer of the rubber composition on the surface of the electroconductive support to form the electroconductive layer (PG0044).