Abstract: An electrophotographic member comprising: a mandrel; and an elastic layer on an outer periphery of the mandrel, the elastic layer containing a polyurethane elastomer including a matrix and domains dispersed in the matrix, a parameter A and a parameter B satisfying a relationship of A<B, where the parameter A indicates a viscoelastic term of each of the plurality of domains and the parameter B indicates a viscoelastic term of the matrix, the elastic layer having a microrubber hardness at a temperature of 23° C. of 20 to 50, and in an indentation test of the elastic layer with a nanoindenter at 23° C., in which a Vickers indenter is indented into the elastic layer at a load speed of 10 mN/30 sec and is maintained at a load of 10 mN for 60 seconds, followed by unloading, strain after 5 seconds from the unloading being 1 ?m or less.

Abstract: Provided is a polyurethane elastomer having excellent friction properties (low friction coefficient), high wear resistance, and low hardness. The polyurethane elastomer includes: a first repeating structural unit represented by the general formula (1) and a second repeating structural unit represented by the general formula (2). The polyurethane elastomer includes a matrix phase and a domain phase dispersed in the matrix phase. The matrix phase includes the first repeating structural unit. The domain phase includes the second repeating structural unit.

Abstract: Provided is a cleaning blade including: an elastic member containing a polyurethane; and a supporting member configured to support the elastic member. The polyurethane has a linear moiety represented by —(CH2)m-. The elastic member has a plate shape having a main surface and a distal end surface forming a distal end-side edge with the main surface, at least on a distal end side. Martens hardness at positions on a bisector at intervals of 30 ?m from a distal end-side edge to a position furthest away from the distal end-side edge by 100 ?m decreases from a distal end-side edge to the position. A Martens hardness HM1 of the elastic member at a position P1 is 1.0 N/mm2 or more. The elastic layer satisfies K?1>K?2>K?3. Further, the cleaning blade has an erosion rate E of 0.6 ?m/g or less.

Abstract: Provided is an electrophotographic electro-conductive member including a support having an electro-conductive outer surface, and an electro-conductive layer. The electro-conductive layer has a matrix containing a crosslinked product of a first rubber and domains containing a crosslinked product of a second rubber and an electron conductive agent. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electro-conductive layer while changing a frequency, a slope at specific frequencies is ?0.8 to ?0.3 in a double logarithmic plot, and an impedance at specific frequency range is 1.0×104? to 1.0×1011?. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electrophotographic electro-conductive member while changing a frequency, an impedance at specific frequency range is 1.0×105? to 1.0×1011?.

Abstract: An electroconductive elastic body includes: a cross-linked product of a first ionic electro-conductive rubber, a cross-linked product of a second ionic electro-conductive rubber, and at least one of a fatty acid and a fatty acid metal salt; wherein the electroconductive elastic body has a matrix that includes the cross-linked product of the first ionic electro-conductive rubber, and a domain that includes the cross-linked product of the second ionic electro-conductive rubber; the cross-linked product of the second ionic electro-conductive rubber includes a polyether skeleton; an electrical resistance of the domain is lower than an electrical resistance of the matrix; in a waveform separation profile of the elastic body as obtained by a small-angle X-ray scattering method, A2 and A1 satisfy a relationship expressed by the following expression (1): 0.005?(A2×C2/A1×C1)?0.030??(1).

Abstract: Provided is an electrophotographic electro-conductive member including a support having an electro-conductive outer surface, and an electro-conductive layer. The electro-conductive layer has a matrix containing a crosslinked product of a first rubber and domains containing a crosslinked product of a second rubber and an electron conductive agent. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electro-conductive layer while changing a frequency, a slope at specific frequencies is ?0.8 to ?0.3 in a double logarithmic plot, and an impedance at specific frequency range is 1.0×104? to 1.0×1011?. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electrophotographic electro-conductive member while changing a frequency, an impedance at specific frequency range is 1.0×105? to 1.0×1011?.

Abstract: An electro-conductive layer of an electrophotographic electro-conductive member has a matrix-domain structure. The matrix contains a first rubber. The domain contains a second rubber and electro-conductive particles. Where ? represents an average of ratios of the cross-sectional area of the electro-conductive particles contained in each of the domains to the cross-sectional area of each of the domains appearing on a cross-section of the electro-conductive layer in a thickness direction, and ? represents a standard deviation of the ratios, ?/? is 0 or more and 0.4 or less, and ? is 20% or more and 40% or less. At least eight of samples with a first cubic shape 9 ?m on a side, which are sampled at arbitrary nine positions on the electro-conductive layer, satisfy the specified condition.

Abstract: An electroconductive elastic body includes: a cross-linked product of a first ionic electro-conductive rubber, a cross-linked product of a second ionic electro-conductive rubber, and at least one of a fatty acid and a fatty acid metal salt; wherein the electroconductive elastic body has a matrix that includes the cross-linked product of the first ionic electro-conductive rubber, and a domain that includes the cross-linked product of the second ionic electro-conductive rubber; the cross-linked product of the second ionic electro-conductive rubber includes a polyether skeleton; an electrical resistance of the domain is lower than an electrical resistance of the matrix; in a waveform separation profile of the elastic body as obtained by a small-angle X-ray scattering method, A2 and A1 satisfy a relationship expressed by the following expression (1): 0.005?(A2×C2/A1×C1)?0.030??(1).

Abstract: An electrophotographic developing member includes an electro-conductive support and an electro-conductive layer provided on the support, wherein the electro-conductive layer has a matrix containing a first rubber and a plurality of domains dispersed in the matrix, and the domain contains a second rubber and an electronic conductive agent and when a frequency is log-log-plotted on a horizontal axis and an impedance is log-log-plotted on a vertical axis with respect to an impedance measured by applying an alternating current voltage having an amplitude of 1 V on the electro-conductive layer while changing a frequency between 1.0×10?2 Hz to 1.0×107 Hz under a specific environment, an inclination of an impedance on a high frequency side is ?0.8 or more and ?0.3 or less and an impedance on a low frequency side is 1.0×104? to 1.0×1011?.

Abstract: Provided is a polymer nanofiber sheet having high delamination resistance, a high mechanical strength, and a high specific surface area. Specifically, provided is a polymer nanofiber sheet, including polymer nanofibers, the polymer nanofibers being laminated and three-dimensionally entangled with each other, in which: at least part of the polymer nanofibers are crosslinked at a crosslinked part having crosslinking portions and a non-crosslinking portion; and the crosslinked part contains a low-molecular weight epoxy compound having a molecular weight of from 100 to 3,000.

Abstract: An electro-conductive layer of an electrophotographic electro-conductive member has a matrix-domain structure. The matrix contains a first rubber. The domain contains a second rubber and electro-conductive particles. Where ? represents an average of ratios of the cross-sectional area of the electro-conductive particles contained in each of the domains to the cross-sectional area of each of the domains appearing on a cross-section of the electro-conductive layer in a thickness direction, and ? represents a standard deviation of the ratios, ?/? is 0 or more and 0.4 or less, and ? is 20% or more and 40% or less. At least eight of samples with a first cubic shape 9 ?m on a side, which are sampled at arbitrary nine positions on the electro-conductive layer, satisfy the specified condition.

Abstract: An electrophotographic developing member includes an electro-conductive support and an electro-conductive layer provided on the support, wherein the electro-conductive layer has a matrix containing a first rubber and a plurality of domains dispersed in the matrix, and the domain contains a second rubber and an electronic conductive agent and when a frequency is log-log-plotted on a horizontal axis and an impedance is log-log-plotted on a vertical axis with respect to an impedance measured by applying an alternating current voltage having an amplitude of 1 V on the electro-conductive layer while changing a frequency between 1.0×10?2 Hz to 1.0×107 Hz under a specific environment, an inclination of an impedance on a high frequency side is ?0.8 or more and ?0.3 or less and an impedance on a low frequency side is 1.0×104? to 1.0×1011?.

Abstract: Provided is a rubber composition for producing a rubber molded article that is improved in fouling resistance while being reduced in tackiness and frictional force despite the presence of the rubber in its surface. The rubber composition includes: a rubber A; and a plastic B, in which: the rubber A includes a non-fluorine-based rubber material; a difference in elastic modulus between the rubber A and the plastic B is 50 MPa or more; a sea-island structure having a sea portion containing the rubber A and a plurality of island portions each containing the plastic B is formed; the plastic B is contained at a content of more than 0 vol % and 50 vol % or less with respect to a total amount of the rubber A and the plastic B; and 90% or more of the plurality of island portions each have a volume of 4,000 ?m3 or less.

Abstract: Provided is a polymer nanofiber sheet having high delamination resistance, a high mechanical strength, and a high specific surface area. Specifically, provided is a polymer nanofiber sheet, including polymer nanofibers, the polymer nanofibers being laminated and three-dimensionally entangled with each other, in which: at least part of the polymer nanofibers are crosslinked at a crosslinked part having crosslinking portions and a non-crosslinking portion; and the crosslinked part contains a low-molecular weight epoxy compound having a molecular weight of from 100 to 3,000.

Abstract: A fiber material contains an assembly of a plurality of nanofiber coated polymer fibers in which a polymer fiber serving as a core fiber is coated with polymer nanofibers, in which the polymer fibers and the polymer nanofibers are fusion-bonded and two or more of the polymer fibers are fusion-bonded to each other in at least one portion.

Abstract: Provided is a sliding member, which is reduced in friction under sliding conditions of high load and high speed under an oilless condition, and is excellent in wear resistance. The sliding member includes: a shaft; and at least one intervening member, in which: the at least one intervening member is located between the shaft and a bearing, and is operable independently of the shaft; and at least one surface of the at least one intervening member on a shaft side includes a sliding surface under one of a radial load and an axial load.

Abstract: A polymer nanofiber sheet including polymer nanofibers having a polymer, the polymer nanofibers being accumulated and three dimensionally entangled. The polymer nanofiber sheet has a low molecular weight organic compound containing at least one 4- or higher-membered ring structure with an ether linkage. The difference between the average solubility parameter of the polymer and the average solubility parameter of the low molecular weight organic compound is less than 8 (J/cm3)1/2.

Abstract: Provided is a nanofiber sheet that has a high mechanical strength, is excellent in durability, and has a high specific surface area. The nanofiber sheet includes: a plurality of nanofibers; and a bulk portion produced by bonding of the nanofibers, in which 7×10?3 portion/?m2 or more of the bulk portion satisfying the following formula is contained: 0.5?X2?Y?5 ?m2??(1) where X represents a diameter (?m) of each of the nanofibers and Y represents an area (?m2) of an inscribed circle of the bulk portion when viewed from a surface.

Abstract: A polymer nanofiber structural body of the present invention is a polymer nanofiber structural body in which polymer nanofibers are integrated, including a first layer and a second layer different from each other in polymer nanofiber existence ratio, in which: both the first layer and the second layer are laminated through a buffer region; the buffer region includes a region in direct contact with both the first layer and the second layer; and a polymer nanofiber existence ratio of the region continuously changes from a polymer nanofiber existence ratio of the first layer to a polymer nanofiber existence ratio of the second layer in a direction from the first layer to the second layer.

Abstract: Provided is a nanofiber accumulated body having a high mechanical strength and excellent in durability, the polymer nanofiber accumulated body including polymer nanofibers each containing a polymer material, the polymer nanofibers being accumulated and three-dimensionally entangled with each other to form the accumulated body, in which: the polymer nanofibers each have a fiber diameter of 3 ?m or less; and the polymer nanofibers each contain 5 wt % to 30 wt % of a low-molecular weight organic compound having at least one ?,?-unsaturated ester structure, with respect to a total weight of the polymer nanofibers.