Process cartridge and process cartridge set

A process cartridge set comprising:

• a first cartridge and a second cartridge configured to be detachably attached to a main body of an electrophotographic apparatus,
• (I) wherein the first cartridge includes a charging unit configured to charge a surface of an electrophotographic photosensitive member, a cleaning unit configured to remove residual toner from a region upstream of the charging unit, and a first frame configured to support the charging unit and the cleaning unit, and
• wherein the second cartridge includes a toner container configured to accommodate toner with which an electrostatic latent image formed on the surface of the electrophotographic photosensitive member is developed to form a toner image on the surface of the electrophotographic photosensitive member,
• (II) wherein the charging unit includes a conductive member disposed to contact the electrophotographic photosensitive member,
• wherein the cleaning unit includes a cleaning blade disposed to contact the electrophotographic photosensitive member,
• wherein the conductive member includes a support having a conductive outer surface and a conductive layer disposed on the outer surface of the support, the conductive layer has a matrix-domain structure including a matrix and a plurality of domains dispersed in the matrix, the matrix contains a first rubber, the domains contain a second rubber, and a surface of the conductive member has a surface roughness Ra of 2.00 μm or less, and
• wherein G1 and G2 both fall within a range of 1.0 N/mm2 or more and 10.0 N/mm2 or less, and an absolute value of a difference between G1 and G2 is 0.1 N/mm2 or more and 7.0 N/mm2 or less, where G1 is a Martens hardness of the matrix measured at the outer surface of the conductive member under a load of 1 mN, and G2 is a Martens hardness of the domains measured at the outer surface of the conductive member under a load of 1 mN, and
• (III) wherein the toner includes at least toner particles, with agglomerates containing silica fine particles and binding components on surfaces of the toner particles,
• wherein CI is 1% by number or more and 15% by number or less, where CI (% by number) is a ratio by number of toner particles with the agglomerates,
• wherein CI, Ca, and Cb satisfy the following inequalities (1) and (2):
• 0.9
• ≤
• Ca
• /
• CI
• ≤
• 1.
• ,
• and
• ⁢
• inequality
• (
• 1
• )
• 0.01
• ≤
• Cb
• /
• CI
• ≤
• 0.1
• ,
• inequality
• (
• 2
• )
• where Ca (% by number) is the ratio by number of toner particles with the agglomerates in the toner after processed under the following ultrasonic condition A, and Cb (% by number) is the ratio by number of toner particles with the agglomerates in the toner after processed under the following ultrasonic condition B:
• ultrasonic condition A:
• an output frequency of 30 kHz, an output power of 0.75 W, and an irradiation time of 300 s, and
• ultrasonic condition B:
• an output frequency of 30 kHz, an output power of 35 W, and an irradiation time of 300 s, and
• wherein a relationship of Dms<Ag is satisfied, where Dms is an arithmetic mean of distances between adjacent domains at the outer surface of the conductive roller, and Ag is an arithmetic mean of Feret diameters of the agglomerates.