Electrophotographic member, process cartridge and electrophotographic apparatus

Patent metadata

Field	Value
Publication number	US-10884352-B2
Application number	US-201916365936-A
Country	US
Kind code	B2
Filing date	Mar 27, 2019
Priority date	Mar 30, 2018
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

The electrophotographic member includes an electro-conductive substrate, a urethane resin having a structure of structural formula (1), an anion, and a resin particle, and has a protrusion derived from the resin particle on an outer surface thereof, the resin particle contains one or both of a urethane resin and a polyamide resin, the resin layer further contains carbon black, and the carbon black extracted from the resin layer has a BET specific surface area of 33 m 2 /g or more and 133 m 2 /g or less, and DBP absorption amount at a 70% torque value in DBP absorption measurement of 42 ml/100 g or more and 90 ml/100 g or less.

First claim

What is claimed is:

1. An electrophotographic member, comprising:
an electro-conductive substrate;
a resin layer as a surface layer on the substrate, the resin layer comprising a urethane resin having a structure of formula (1), an anion and a resin particle, the resin layer further comprising carbon black

where R1 represents a hydrogen atom, or a monovalent hydrocarbon group having 1 to 12 carbon atoms, X1 to X3 independently represent a structure selected from the group consisting of formulae (X101) to (X103), or a monovalent hydrocarbon group having 1 to 12 carbon atoms, with the proviso that at least one of X1 to X3 is one of formulae (X101) to (X103)

where R2 represents a linear or branched divalent hydrocarbon group, R3 represents a linear or branched divalent hydrocarbon group, R4 represents a linear or branched divalent hydrocarbon group, * represents a point of attachment to a nitrogen atom in formula (1), and ** represents a point of attachment to a carbon atom in a polymer chain forming the resin; and
the electrophotographic member having a protrusion derived from the resin particle on an outer surface thereof, the resin particle comprising at least one of a urethane resin and a polyamide resin, wherein
carbon black extracted from the resin layer has a BET specific surface area of 33 to 133 m 2 /g, and DBP absorption amount at a 70% torque value in DBP absorption measurement of 42 to 90 ml/100 g, and
1468≤Z2/Z1≤20175 and 0.056≤Z3/(Z2·Z4)≤0.813 when Z1 is an ionic equivalent (eq) of a resin of structural formula (1) contained in 1 part by mass of the resin layer, Z2 is a content (parts by mass) of the carbon black contained in 100 parts by mass of the resin layer, Z3 is a percentage (%) of the cross-sectional area of the resin particle in a cross-sectional area of the resin layer, and Z4 is d90 (μm) in a cumulative distribution of an area-equivalent diameter of the resin particle in the cross-sectional area of the resin layer.

2. The electrophotographic member according to claim 1 , wherein [DBP absorption at maximum torque]−[DBP absorption at 30% torque] in DBP absorption measurement of the carbon black extracted from the resin layer is 40 ml/100 g or less.

3. The electrophotographic member according to claim 1 , wherein the BET specific surface area is 50 to 90 m 2 /g as measured with respect to the carbon black, and DBP absorption measurement is 70 80 ml/100 g at a 70% torque value.

4. The electrophotographic member according to claim 1 , wherein the carbon black has a pH of 4.5 or less.

5. The electrophotographic member according to claim 1 , wherein the carbon black has a pH of 3.0 or more.

6. The electrophotographic member according to claim 1 , wherein the urethane resin is a reaction product of an ionic compound having at least one member selected from the group consisting of hydroxyl group, amino group and glycidyl group in a quaternary ammonium cation structure, a polyisocyanate and a polymer polyol.

7. The electrophotographic member according to claim 6 , wherein the ionic compound has a structure selected from the group consisting of formulae (IC-1) to (IC-6)

8. The electrophotographic member according to claim 1 , wherein the electrophotographic member is a development member.

9. The electrophotographic member according to claim 1 , wherein the electrophotographic member is a charging member.

10. The electrophotographic member according to claim 1 , wherein the electrophotographic member is a cleaning member.

11. A process cartridge configured to be detachably attached to a main body of an electrophotographic image forming apparatus, the process cartridge comprising at least one electrophotographic member selected from the group consisting of a charging member, a development member and a cleaning member,
the electrophotographic member comprises an electro-conductive substrate and a resin layer as a surface layer on the substrate, the resin layer comprising a urethane resin having a structure of formula (1), an anion and a resin particle, the resin layer further comprising carbon black

where, R1 represents a hydrogen atom, or a monovalent hydrocarbon group having 1 to 12 carbon atoms, X1 to X3 independently represent a structure selected from the group consisting of formulae (X101) to (X103), or a monovalent hydrocarbon group having 1 to 12 carbon atoms, with the proviso that at least one of X1 to X3 is one of formulae (X101) to (X103)

where R2 represents a linear or branched divalent hydrocarbon group, R3 represents a linear or branched divalent hydrocarbon group, R4 represents a linear or branched divalent hydrocarbon group, * represents a point of attachment to a nitrogen atom in formula (1), and ** represents a point of attachment to a carbon atom in a polymer chain forming the resin; and
the electrophotographic member having a protrusion derived from the resin particle on an outer surface thereof, the resin particle comprising at least one of a urethane resin and a polyamide resin, wherein
carbon black extracted from the resin layer has a BET specific surface area of 33 to 133 m 2 /g, and DBP absorption amount at a 70% torque value in DBP absorption measurement of 42 to 90 ml/100 g, and
1468≤Z2/Z1≤20175 and 0.056≤Z3/(Z2·Z4)≤0.813 when Z1 is an ionic equivalent (eq) of a resin of structural formula (1) contained in 1 part by mass of the resin layer, Z2 is a content (parts by mass) of the carbon black contained in 100 parts by mass of the resin layer, Z3 is a percentage (%) of the cross-sectional area of the resin particle in a cross-sectional area of the resin layer, and Z4 is d90 (μm) in a cumulative distribution of an area-equivalent diameter of the resin particle in the cross-sectional area of the resin layer.

12. An electrophotographic image forming apparatus, comprising:
an electrophotographic photosensitive member;
a charging member disposed such that the electrophotographic photosensitive member can be charged;
a development member; and
a cleaning member,
at least one of the charging member, the development member and the cleaning member being an electrophotographic member comprising an electro-conductive substrate, with a resin layer as a surface layer on the substrate,
the resin layer comprising a urethane resin having a structure of formula (1), an anion and a resin particle, the resin layer further comprising carbon black

where R1 represents a hydrogen atom, or a monovalent hydrocarbon group having 1 to 12 carbon atoms, X1 to X3 independently represent a structure selected from the group consisting of formulae (X101) to (X103), or a

Assignees

• Canon Kk

Inventors

• Yamada Masaki
• Komatsu Hiroaki
• Arimura Hideya

Classifications

• G03G15/1685

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

• G03G21/0005

  for removing solid developer or debris from the electrographic recording medium · CPC title

• G03G15/0818 Primary

  characterised by the structure of the donor member, e.g. surface properties · CPC title

• G03G15/0233 Primary

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

• G03G5/043

  Photoconductive layers characterised by having two or more layers or characterised by their composite structure · CPC title