Electrophotographic electro-conductive member, process cartridge, and electrophotographic image forming device

Patent metadata

Field	Value
Publication number	US-11586121-B2
Application number	US-202217658685-A
Country	US
Kind code	B2
Filing date	Apr 11, 2022
Priority date	Oct 18, 2019
Publication date	Feb 21, 2023
Grant date	Feb 21, 2023

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 1.0×10 4 Ω to 1.0×10 11 Ω. 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 1.0×10 5 Ω to 1.0×10 11 Ω.

First claim

What is claimed is:

1. An electrophotographic electro-conductive member comprising:
a support having an electro-conductive outer surface;
an electro-conductive layer on the outer surface of the support; and
a surface layer on an outer surface of the electro-conductive layer,
the electro-conductive layer having a matrix containing a crosslinked product of a first rubber and a plurality of domains dispersed in the matrix,
the domains each comprising a crosslinked product of a second rubber and an electron conductive agent, wherein
when a platinum electrode is directly provided on an outer surface of the electro-conductive layer, and impedance is measured under an environment of a temperature of 23° C. and a relative humidity of 50% by applying an alternating voltage having an amplitude of 1 V between the electro-conductive outer surface of the support and the platinum electrode while changing a frequency thereof between 1.0×10 −2 Hz and 1.0×10 7 Hz, in a double logarithmic plot with a frequency on an abscissa and an impedance on an ordinate, a slope at frequencies of 1.0×10 6 Hz to 1.0×10 7 Hz is −0.8 or more and −0.3 or less, and an impedance at a frequency of 1.0×10 −2 Hz to 1.0×10 1 Hz is 1.0×10 4 Ω to 1.0×10 11 Ω, and
when a platinum electrode is directly provided on an outer surface of the electrophotographic electro-conductive member, and impedance is measured under the environment having a temperature of 23° C. and a relative humidity of 50% by applying an alternating voltage having an amplitude of 1 V between the electro-conductive outer surface of the support and the platinum electrode while changing a frequency thereof between 1.0×10 −2 Hz and 1.0×10 7 Hz, an impedance at a frequency of 1.0×10 −2 Hz to 1.0×10 1 Hz is 1.0×10 5 Ω to 1.0×10 11 Ω.

2. The electrophotographic electro-conductive member according to claim 1 , wherein the electro-conductive layer is directly provided on the outer surface of the support.

3. The electrophotographic electro-conductive member according to claim 1 , further comprising an electro-conductive resin layer between the electro-conductive layer and the electro-conductive outer surface of the support, wherein when a platinum electrode is directly provided on an outer surface of the resin layer, and an impedance is measured under the environment having a temperature of 23° C. and a relative humidity of 50% by applying an alternating voltage having an amplitude of 1 V between the electro-conductive outer surface of the support and the platinum electrode while changing a frequency thereof between 1.0×10 −2 Hz and 1.0×10 7 Hz, an impedance at a frequency of 1.0×10 −2 Hz to 1.0×10 1 Hz is 1.0×10 −5 Ω to 1.0×10 1 Ω.

4. The electrophotographic electro-conductive member according to claim 1 , wherein the matrix has a volume resistivity of more than 1.0×10 12 Ω·cm and 1.0×10 17 Ω·cm or less.

5. The electrophotographic electro-conductive member according to claim 1 , wherein an arithmetic average Dm of distances between the domains adjacent to each other is 0.2 μm or more and 2.0 μm or less.

6. The electrophotographic electro-conductive member according to claim 1 , wherein
when defining a length of the electro-conductive layer in a longitudinal direction as L and defining a thickness of the electro-conductive layer as T, and
when a 15-micrometer square observation region is put at each of arbitrary three positions in a thickness region from the outer surface of the electro-conductive layer to a depth of from 0.1 T to 0.9 T on each of cross sections in a thickness direction of the electro-conductive layer at three positions including a center of the electro-conductive layer in the longitudinal direction and points from both edges of the electro-conductive layer towards the center by L/4, among the domains observed in each of the observation regions 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 electron conductive agent in a domain with respect to a cross sectional area of the domain is 20% or more; and
(2) A/B is 1.00 or more and 1.10 or less when A is a perimeter of a domain, and B is an envelope perimeter of the domain.

7. The electrophotographic electro-conductive member according to claim 1 , wherein when
an average of ratios of a cross sectional area of the electron conductive agent contained in each of the domains appearing on a cross section of the electro-conductive layer in a thickness direction thereof to a cross sectional area of each of the domains is defined as μ, and a standard deviation of the ratios is defined as σ,
σ/μ is 0 or more and 0.4 or less,
μ is 20% or more and 40% or less, and wherein
among cubic shaped sample cubes each having 9 μm on a side sampled at arbitrary nine portions from the electro conductive layer, at least eight of the sample cubes each satisfy the following requirement (3):
(3) when one sample cube is divided into 27 unit cubes having 3 μm on a side, and a volume Vd of the domains in each of the unit cubes is calculated, the number of the unit cubes each having a Vd of from 2.7 μm 3 to 10.8 μm 3 is at least 20.

8. The electrophotographic electro-conductive member according to claim 1 , wherein the surface layer contains at least one kind of binder resin, and at least one kind of electron conductive agent or ion conductive agent.

9. The electrophotographic electro-conductive member according to claim 8 , wherein the binder resin is a urethane resin.

10. The electrophotographic electro-conductive member according to claim 9 , wherein the urethane resin has a urethane group concentration of 1.5% or more and 6.5% or less.

11. The electrophotographic electro-conductive member according to claim 9 , wherein the urethane resin has at least one structure selected from the group consisting of structures represented by the structural formulae (1) to (3):

in the structural formulae (1) to (3), R 1 to R 3 each independently represent a linear or branched divalent hydrocarbon group having 4 or more and 8 or less carbon atoms.

12. The electrophotographic electro-conductive member according to claim 1 , wherein
the surface layer contains a binder resin and an electron conductive agent, and
the surface layer has protrusions derived from an exposed part of the electron conductive agent on a surface thereof, and has a universal hardness of 1.0 N/mm 2 or more and 7.0 N/mm 2 or less at a position of a depth of 1 μm from the surface.

13. The electrophotographic electro-conductive member according to claim 1 , wherein the surface layer has a volume resistivity of 1.0×10 4 Ω·cm or more and 1.0×10 15 Ω·cm or less.

14. The electrophotographic electro-conductive member according to claim 1 , wherein the surface layer contains a roughening particle having a number-average particle diameter of 3 μm or more and 30 μm or less, and has a protrusion derived from the roughening particle on a surface thereof.

15. A process cartridge, which is removably mounted to a main body of an electrophotographic image forming apparatus, the process cartridge comprising an electrophotographic electro-conductive member
the electrophotographic electro-conductive member comprising:
a support having an electro-conductive outer surface;
an electro-conductive layer on the outer surface of the support; and
a surface layer on an outer surface of the electro-conductive layer,
the electro-conductive layer having a matrix containing a crosslinked product of a first rubbe

Assignees

• Canon Kk

Inventors

• Yamada Masaki
• Kikuchi Yuichi
• Takashima Kenji
• Hino Tetsuo
• Yamauchi Kazuhiro
• Furukawa Takumi

Classifications

• G03G15/1685

  Structure, details of the transfer member, e.g. chemical composition · CPC title

• G03G15/0812

  characterised by the developer regulating means, e.g. structure of doctor blade · CPC title

• G03G15/0233 Primary

  Structure, details of the charging member, e.g. chemical composition, surface properties · CPC title

• G03G15/0806

  on a donor element, e.g. belt, roller (complete developer unit G03G15/0896) · CPC title

• F16C13/00

  Rolls, drums, discs, or the like (guide rollers in feeding webs B65H27/00; calender rolls, bearings therefor D21G1/02; rotary drums or rollers for heat-exchange or heat-transfer apparatus F28F5/02); Bearings or mountings therefor · CPC title