An electroconductive member for electrophotography has an electroconductive support and an electroconductive layer in the order mentioned. The electroconductive layer has a matrix including a crosslinked product of a first rubber, and a domain including a crosslinked product of a second rubber and an electroconductive particle. The impedance of the outer surface of the electroconductive member is 1.0×10.sup.3 to 1.0×10.sup.8Ω). 80% by number or more of domains observed at each of a total of nine 15-μm square observation regions, which are disposed at any three points in a thickness region from the outer surface to a specific depth on each of cross sections in the thickness direction at three points: the center of the electroconductive layer in the longitudinal direction and points at a specific distance from the both edges of the electroconductive layer toward the center, satisfy specific requirements.

Provided is a fixing member for electrophotography having excellent toner releasability even when used for a long time period. The fixing member includes a base layer, an elastic layer, and a surface layer in the stated order. The surface layer contains a fluorine resin and a fluorine oil having a perfluoropolyether structure. The mass P11 of an adhered substance including the fluorine oil, adhered in the unit area of the detection surface of a QCM sensor when a measurement sample collected from the surface layer is subjected to a predetermined treatment (i), is 1.0×10.sup.2 ng or more and 1.0×10.sup.4 ng or less, and the mass P12 of an adhered substance including the fluorine oil, adhered in the unit area of the detection surface of the QCM sensor when the sample is subjected to a predetermined treatment (ii), is 0.5×P11 or more and 1.2×P11 or less.

The industrial roll according to the invention includes a core member made of a metal, a first adhesive layer formed in contact with an outer surface of the core member, a second adhesive layer formed on an outer surface side of the first adhesive layer, and a cover member formed in contact with an outer surface of the second adhesive layer and made of an elastic material. The first adhesive layer is made of a material with better adhesive properties to the core member than to the cover member, and the second adhesive layer is made of a material with better adhesive properties to the cover member than to the core member.

The industrial roll according to the invention includes a core member made of a metal, a first adhesive layer formed in contact with an outer surface of the core member, a second adhesive layer formed on an outer surface side of the first adhesive layer, and a cover member formed in contact with an outer surface of the second adhesive layer and made of an elastic material. The first adhesive layer is made of a material with better adhesive properties to the core member than to the cover member, and the second adhesive layer is made of a material with better adhesive properties to the cover member than to the core member.

A device for measuring a wear condition on the plain bearing surface of a sensor plate comprises a measuring apparatus, which has wear sensors of a sensor plate integrated into the plain bearing surface. To capture the material removal at the plain bearing surface due to wear an evaluation apparatus is in signal connection with the wear sensors. The evaluation apparatus is designed, with respect to programming, in such a way that a change, in particular an increase, in the ohmic resistance value of the electrical conductor of a certain wear sensor can be captured in dependence on its own material removal, in order to thereby ensure that the amount of the material removal at the plain bearing surface and/or the remaining thickness of the plain bearing surface at the location of said certain wear sensor can be inferred from the detected change in the resistance value.

An end cap assembly for a conveyor roll includes an end cap configured to fit over an end of the conveyor roll, and the end cap has an opening. The end cap assembly further includes a spring member configured to be positioned between the end of the conveyor roll and the end cap, and a fastener that is insertable into the opening of the end cap. The fastener is configured to cooperate with the spring member to apply a retention force to assist in retaining the end cap on the conveyor roll.

An elastic body layer is composed of a conductive rubber composition containing an isoprene rubber, a rubber other than the isoprene rubber, and carbon black. The elastic body layer is phase-separated into a first rubber phase containing the isoprene rubber and a second rubber phase containing the rubber other than the isoprene rubber; in the range of a 5 μm×5 μm square of an arbitrary cross section of the elastic body layer, the area ratio of the first rubber phase is within a range of 10 to 90%. The resistance value of the elastic body layer is within a range of 1.0×10.sup.3 to 1.0×10.sup.6Ω. A surface layer contains an electronic conductive agent and a crosslinked body of at least one polyurethane resin of an ether polyurethane resin and a carbonate polyurethane resin, and the glass transition point of the surface layer is within a range of −10 to −70° C.

An elastic body layer is composed of a conductive rubber composition containing an isoprene rubber, a rubber other than the isoprene rubber, and carbon black. The elastic body layer is phase-separated into a first rubber phase containing the isoprene rubber and a second rubber phase containing the rubber other than the isoprene rubber; in the range of a 5 μm×5 μm square of an arbitrary cross section of the elastic body layer, the area ratio of the first rubber phase is within a range of 10 to 90%. The resistance value of the elastic body layer is within a range of 1.0×10.sup.3 to 1.0×10.sup.6Ω. A surface layer contains an electronic conductive agent and a crosslinked body of at least one polyurethane resin of an ether polyurethane resin and a carbonate polyurethane resin, and the glass transition point of the surface layer is within a range of −10 to −70° C.

In a charging roll, grooves regularly defining spirals are formed on an elastic body layer, with a groove width of 4 μm to 280 μm and a groove depth of 2 μm to 30 μm. On an outer peripheral surface of the elastic body layer, an area ratio between an area of a bottom surface of the groove and an area of a plane part is 0.3 to 2.4. The surface layer includes a binder polymer and a roughness forming particle. The roughness forming particle is arranged on the plane part and the groove. A surface roughness of the surface layer on the groove is 2 μm to 16 μm. A surface roughness of the entire surface layer is 5 μm to 26 μm. A thickness of the binder polymer covering the roughness forming particle on the groove is greater than that on the plane part.

A conductive roller includes: a core member including an outer surface along and about an axial line thereof; and a surface layer arranged along the outer surface of the core member. The surface layer includes a conductive portion, and a surface roughness imparting material in a form of particles dispersed in the conductive portion. An average particle size of the surface roughness imparting material is in a range of 6 micrometers or greater and less than 10 micrometers. The number of particles of the surface roughness imparting material per unit area of the surface layer is in a range of 3.5×10.sup.5 particles per mm.sup.2 or greater and 7.5×10.sup.5 particles per mm.sup.2 or less. An average thickness of the surface layer is in a range of 0.2 micrometers or greater and 5.5 micrometers or less.