Electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10732526-B2
Application number	US-201716471154-A
Country	US
Kind code	B2
Filing date	Nov 30, 2017
Priority date	Dec 26, 2016
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

An electrophotographic photosensitive member ( 1 ) includes a conductive substrate ( 2 ) and a photosensitive layer ( 3 ). The photosensitive layer ( 3 ) is a single-layer photosensitive layer ( 3 c ) and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin represented by general formula (1).

In general formula (1), Q 1 , Q 2 , Q 3 , and Q 4 each represent a methyl group or a hydrogen atom. r, s, t, and u each represent a number greater than or equal to 15 and less than or equal to 35. X and Y each represent a divalent group represented by chemical formula (2A), chemical formula (2B), chemical formula (2C), or chemical formula (2D), and X and Y are different from each other

First claim

The invention claimed is:

1. An electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer, wherein
the photosensitive layer is a single-layer photosensitive layer and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin,
the binder resin includes a polyarylate resin,
the polyarylate resin is represented by general formula (1) shown below,
the electron transport material is represented by general formula (ETM1), general formula (ETM2), general formula (ETM3), general formula (ETM4), or general formula (ETM5) shown below,
a scratch resistant depth of the photosensitive layer is no greater than 0.50 μm, and
a Vickers hardness of the photosensitive layer is at least 17.0 HV,

where in general formula (1),
Q 1 , Q 2 , Q 3 , and Q 4 each represent, independently of one another, a methyl group or a hydrogen atom,
r, s, t, and u each represent, independently of one another, a number greater than or equal to 15 and less than or equal to 35,
r+s+t+u=100,
r+t=s+u,
X and Y each represent, independently of one another, a divalent group represented by chemical formula (2A), chemical formula (2B), chemical formula (2C), or chemical formula (2D) shown below, and
X and Y are different from each other,

in general formula (ETM1),
R 1 and R 4 each represent, independently of one another, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 6,
R 2 and R 3 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
a and b each represent, independently of one another, an integer of at least 0 and no greater than 4,
when a represents an integer of at least 2 and no greater than 4, chemical groups R 2 may be the same as or different from one another, and
when b represents an integer of at least 2 and no greater than 4, chemical groups R 3 may be the same as or different from one another,
in general formula (ETM2), R 5 represents a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 6 and optionally having a halogen atom,
in general formula (ETM3), R 6 and R 7 each represent, independently of one another, a hydrogen atom or an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having an alkyl group having a carbon number of at least 1 and no greater than 3,
in general formula (ETM4), R 8 and R 9 each represent, independently of one another, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 6, and R 10 represents a halogen atom or a hydrogen atom, and
in general formula (ETM5),
R 11 , R 12 , R 13 , R 14 , and R 15 each represent, independently of one another, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 6,
R 16 represents a hydrogen atom or an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having a halogen atom, and
G 1 and G 2 each represent, independently of one another, an oxygen atom or a sulfur atom.

2. The electrophotographic photosensitive member according to claim 1 , wherein
in general formula (1), X and Y each represent, independently of one another, the divalent group represented by chemical formula (2A), chemical formula (2B), or chemical formula (2D).

3. The electrophotographic photosensitive member according to claim 2 , wherein
in general formula (1), X is the divalent group represented by chemical formula (2D), and Y is the divalent group represented by chemical formula (2A) or chemical formula (2B).

4. The electrophotographic photosensitive member according to claim 1 , wherein
in general formula (1), Q 1 , Q 2 , Q 3 , and Q 4 each represent a methyl group.

5. The electrophotographic photosensitive member according to claim 1 , wherein
in general formula (1), r, s, t, and u each represent, independently of one another, a number greater than or equal to 20 and less than or equal to 30.

6. The electrophotographic photosensitive member according to claim 1 , wherein
the polyarylate resin is represented by chemical formula (R-1), chemical formula (R-2), chemical formula (R-3), chemical formula (R-4), chemical formula (R-5), chemical formula (R-6), chemical formula (R-7), chemical formula (R-8), or chemical formula (R-9) shown below

7. The electrophotographic photosensitive member according to claim 1 , wherein
the electron transport material is represented by general formula (ETM1), general formula (ETM2), or general formula (ETM5).

8. The electrophotographic photosensitive member according to claim 1 , wherein
in general formula (ETM1),
R 1 and R 4 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6, and
a and b each represent 0,
in general formula (ETM2), R 5 represents an alkyl group having a carbon number of at least 1 and no greater than 6 and optionally having a halogen atom,
in general formula (ETM3), R 6 and R 7 each represent, independently of one another, an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having an alkyl group having a carbon number of at least 1 and no greater than 3,
in general formula (ETM4), R 8 and R 9 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6, and
R 10 represents a halogen atom, and
in general formula (ETM5),
R 11 , R 13 , and R 15 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
R 12 and R 14 each represent a hydrogen atom,
R 16 represents an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having a halogen atom, and
G 1 and G 2 each represent an oxygen atom.

9. The electrophotographic photosensitive member according to claim 8 , wherein
the electron transport material is represented by chemical formula (ETM1-1), chemical formula (ETM2-1), chemical formula (ETM3-1), chemical formula (ETM4-1), or chemical formula (ETM5-1) shown below

10. The electrophotographic photosensitive member according to claim 1 , wherein
the hole transport material includes a compound represented by general formula (HTM1) shown below,

where in general formula (HTM1),
R 20 , R 21 , R 22 , and R 23 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
c, d, e, and f each represent, independently of one another, an integer of at least 0 and no greater than 5,
when c represents an integer of at least 2 and no greater t

Assignees

• Kyocera Document Solutions Inc

Inventors

• Shimizu Tomofumi
• Maruo Keiji
• Azuma Jun

Classifications

• C09B47/30

  Metal-free phthalocyanines · CPC title

• G03G5/0616

  Hydrazines; Hydrazones · CPC title

• C07D231/18

  One oxygen or sulfur atom · CPC title

• G03G5/0651

  containing four relevant rings · CPC title

• G03G5/0631

  containing two hetero atoms · CPC title