Electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10649351-B2
Application number	US-201716472178-A
Country	US
Kind code	B2
Filing date	Nov 30, 2017
Priority date	Dec 26, 2016
Publication date	May 12, 2020
Grant date	May 12, 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)

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 hole transport material is represented by general formula (HTM1), general formula (HTM2), general formula (HTM3), general formula (HTM4), general formula (HTM5), general formula (HTM6), or general formula (HTM7) 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 (HTM1),
R 1 , R 2 , R 3 , 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,
a1, a2, a3, and a4 each represent, independently of one another, an integer of at least 0 and no greater than 5,
when a1 represents an integer of at least 2 and no greater than 5, chemical groups R 1 may be the same as or different from one another,
when a2 represents an integer of at least 2 and no greater than 5, chemical groups R 2 may be the same as or different from one another,
when a3 represents an integer of at least 2 and no greater than 5, chemical groups R 3 may be the same as or different from one another, and
when a4 represents an integer of at least 2 and no greater than 5, chemical groups R 4 may be the same as or different from one another,
in general formula (HTM2), R 5 , R 6 , R 7 , and R 8 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,
in general formula (HTM3),
R 9 , R 10 , R 11 , and R 12 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
b1, b2, b3, and b4 each represent, independently of one another, an integer of at least 0 and no greater than 5,
when b1 represents an integer of at least 2 and no greater than 5, chemical groups R 9 may be the same as or different from one another,
when b2 represents an integer of at least 2 and no greater than 5, chemical groups R 10 may be the same as or different from one another,
when b3 represents an integer of at least 2 and no greater than 5, chemical groups R 11 may be the same as or different from one another, and
when b4 represents an integer of at least 2 and no greater than 5, chemical groups R 12 may be the same as or different from one another,
in general formula (HTM4),
R 13 , R 14 , R 15 , and R 16 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
c1, c2, c3, and c4 each represent, independently of one another, an integer of at least 0 and no greater than 5,
when c1 represents an integer of at least 2 and no greater than 5, chemical groups R 13 may be the same as or different from one another,
when c2 represents an integer of at least 2 and no greater than 5, chemical groups R 14 may be the same as or different from one another,
when c3 represents an integer of at least 2 and no greater than 5, chemical groups R 15 may be the same as or different from one another, and
when c4 represents an integer of at least 2 and no greater than 5, chemical groups R 16 may be the same as or different from one another,
in general formula (ETM5), R 17 , R 18 , R 19 , R 20 , and R 21 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,
in general formula (HTM6),
R 22 , R 23 , and R 24 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
d1, d2, and d3 each represent, independently of one another, an integer of at least 0 and no greater than 5,
when d1 represents an integer of at least 2 and no greater than 5, chemical groups R 22 may be the same as or different from one another,
when d2 represents an integer of at least 2 and no greater than 5, chemical groups R 23 may be the same as or different from one another,
when d3 represents an integer of at least 2 and no greater than 5, chemical groups R 24 may be the same as or different from one another, and
R 25 represents a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 6, and
in general formula (HTM7),
R 26 , R 27 , and R 28 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 6,
e1, e2, and e3 each represent, independently of one another, an integer of at least 0 and no greater than 5,
when e1 represents an integer of at least 2 and no greater than 5, chemical groups R 26 may be the same as or different from one another,
when e2 represents an integer of at least 2 and no greater than 5, chemical groups R 27 may be the same as or different from one another,
when e3 represents an integer of at least 2 and no greater than 5, chemical groups R 28 may be the same as or different from one another, and
R 29 , R 30 , and R 31 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.

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 represents the divalent group represented by chemical formula (2D), and Y represents 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 represent

Assignees

• Kyocera Document Solutions Inc

Inventors

• Shimizu Tomofumi
• Azuma Jun
• Maruo Keiji

Classifications

• G03G5/0668

  containing only one methine or polymethine group · CPC title

• G03G5/0546

  Polymers comprising at least one carboxyl radical, e.g. polyacrylic acid, polycrotonic acid, polymaleic acid; Derivatives thereof, e.g. their esters, salts, anhydrides, nitriles, amides · CPC title

• G03G5/043 Primary

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

• G03G5/0616

  Hydrazines; Hydrazones · CPC title

• G03G5/0614

  Amines · CPC title