Granted Patent B2

US 12,306,560 · App. 18/441,115 · Granted May 20, 2025

Inventors: Yuji Kitano (Kanagawa, JP); Makoto Souma (Kanagawa, JP); Naoko Kasai (Kanagawa, JP); Yutaro Yoshida (Kanagawa, JP); Masatsugu Toyonori (Kanagawa, JP); Yasutomo Tsuji (Saitama, JP)

Assignee: CANON KABUSHIKI KAISHA

G03G15/162C08K3/22C08L33/08C08K2003/2231C08K2201/001

Abstract

Claims (36)

1. An electrophotographic member having a base layer and a surface layer,

wherein the surface layer comprises

a binder resin; and

a plurality of particles comprising a conductive tin oxide, in the binder resin,

a content ratio of the particles comprising a conductive tin oxide, in the surface layer, is 2.0 to 10.0 vol %, and

a value of an L function denoting a relationship of a distribution of the particles comprising a conductive tin oxide, as observed from a surface of the surface layer, is always positive in a range of 300 nm to 1 μm of a distance from barycentric coordinates of the particles.

2. The electrophotographic member according to claim 1 ,

wherein the surface layer further comprises particles comprising a fluororesin, and a dispersing agent dispersing the particles comprising a fluororesin,

the dispersing agent is a polymer having a structure represented by Formula (1) and a structure represented by Formula (2);

in Formula (1), R 11 represents a hydrogen atom or a methyl group, R 12 represents a single bond or an alkylene group having 1 to 3 carbon atoms, and Rf represents a perfluoroalkyl group having 1 to 6 carbon atoms;

in Formula (2), R 21 and R 22 each independently represent a hydrogen atom or a methyl group, and Y A1 represents an unsubstituted alkylene group,

Y B represents

an unsubstituted alkylene group,

an alkylene group substituted with a halogen atom,

an alkylene group substituted with a hydroxy group,

—COO—,

—NHCO—, or

—NHCOO—, or

a divalent linking group derived through combination of one or more selected from among these groups and bonds with —O— or —S—, or

a single bond,

Z A represents a structure represented by Formula (3), a cyano group or a phenyl group, and

n represents an integer of 25 to 150, and

in Formula (3), Z A1 represents an alkyl group having 1 to 4 carbon atoms.

3. The electrophotographic member according to claim 2 , wherein the particles comprising a fluororesin comprise polytetrafluoroethylene particles.

4. The electrophotographic member according to claim 1 , wherein a volume resistivity of a powder compact of the particles comprising a conductive tin oxide is 0.01 to 100 Ω·cm.

5. The electrophotographic member according to claim 4 , wherein the volume resistivity is 1 to 5 Ω·cm.

6. The electrophotographic member according to claim 5 , wherein a surface resistivity of the surface layer is 1×10 9 Ω/square to 1×10 11 Ω/square.

7. The electrophotographic member according to claim 4 , wherein the particles comprising a conductive tin oxide comprise an antimony.

8. The electrophotographic member according to claim 1 , wherein the binder resin comprises an acrylic resin.

9. The electrophotographic member according to claim 8 , wherein the acrylic resin is at least one polymer selected from the group consisting of a pentaerythritol tri(meth)acrylate and a pentaerythritol tetra(meth)acrylate.

10. The electrophotographic member according to claim 1 , wherein the electrophotographic member is an intermediate transfer member.

11. The electrophotographic member according to claim 1 , wherein the electrophotographic member has an endless belt shape.

12. An electrophotographic image forming apparatus comprising:

an image bearing member supporting a toner image thereon; and

an intermediate transfer member onto which the toner image formed on the image bearing member is primary-transferred, and which secondary-transfers, onto a recording material, the primary-transferred toner image,

wherein the intermediate transfer member is the electrophotographic member according to claim 1 .

Assignments (1)

Priority Claims (2)

Continuity (1)

References Cited (23)