Positively chargeable single-layer electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-9785062-B2
Application number	US-201615171467-A
Country	US
Kind code	B2
Filing date	Jun 2, 2016
Priority date	Jun 8, 2015
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

In a positively chargeable single-layer electrophotographic photosensitive member, a photosensitive layer contains at least a hole transport material, and particles of a first resin. A compound represented by general formula (1) is contained as the hole transport material. In the general formula (1), R 1 represents an alkyl group having a carbon number of at least 2 and no greater than 4. R 2 , R 3 , R 4 , R 5 , and R 6 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 4. Ar 1 and Ar 2 each represent, independently of each other, a hydrogen atom or an optionally substituted aryl group having a carbon number of at least 6 and no greater than 20. At least one of Ar 1 and Ar 2 represents an optionally substituted aryl group having a carbon number of at least 6 and no greater than 20.

First claim

What is claimed is:

1. A positively chargeable single-layer electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer, wherein
the photosensitive layer contains at least a charge generating material, a hole transport material, and particles of a first resin, and
a compound represented by general formula (1) shown below is contained as the hole transport material,

where, in the general formula (1),
R 1 represents an alkyl group having a carbon number of 2 or 4,
R 3 , R 5 , and R 6 each represent a hydrogen atom,
R 2 and R 4 each represent, independently of each other, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 4, and
either one of Ar 1 and Ar 2 represents an aryl group having a carbon number of at least 6 and no greater than 20 and the other represents a hydrogen atom.

2. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the first resin is a silicone resin, a melamine resin, or a benzoguanamine resin.

3. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the particles of the first resin have a volume median diameter of at least 0.05 μm and no greater than 5.00 μm.

4. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the particles of the first resin have a content rate of no greater than 25.0% by mass relative to a total mass of the photosensitive layer.

5. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
in the general formula (1), R 1 represents an alkyl group having a carbon number of 2,
R 2 , R 3 , R 5 , and R 6 each represent a hydrogen atom,
R 4 represents a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 4, and
either one of Ar 1 and Ar 2 represents an aryl group having a carbon number of at least 6 and no greater than 14 and the other represents a hydrogen atom.

6. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
in the general formula (1),
R 1 represents an alkyl group having a carbon number of 2,
R 2 represents an alkyl group having a carbon number of at least 1 and no greater than 4,
R 3 , R 4 , R 5 , and R 6 each represent a hydrogen atom, and
either one of Ar 1 and Ar 2 represents an aryl group having a carbon number of at least 6 and no greater than 14 and the other represents a hydrogen atom, or
in the general formula (1),
R 1 represents an alkyl group having a carbon number of 4,
R 2 , R 3 , R 4 , R 5 , and R 6 each represent a hydrogen atom, and
either one of Ar 1 and Ar 2 represents an aryl group having a carbon number of at least 6 and no greater than 14 and the other represents a hydrogen atom.

7. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the photosensitive layer further contains a second resin as a binder resin, and
the second resin is represented by general formula (2) shown below,

where, in the general formula (2),
R 21 , R 22 , R 23 , and R 24 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 3, and
m+n=1.00 and 0.00<m≦1.00.

8. The positively chargeable single-layer electrophotographic photosensitive member according to claim 7 , wherein
in the general formula (2),
R 21 and R 22 each represent a hydrogen atom, and
m=1.00 and n=0.00.

9. The positively chargeable single-layer electrophotographic photosensitive member according to claim 7 , wherein
in the general formula (2),
R 21 and R 22 each represent, independently of each other, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 3,
R 23 and R 24 each represent a hydrogen atom, and
m+n=1.00 and 0.50<m≦0.70.

10. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the photosensitive layer further contains an electron transport material, and
the electron transport material is represented by general formula (3), (4), (5), or (6) shown below,

where, in the general formulas (3), (4), (5), and (6),
R 31 , R 32 , R 33 , R 34 , R 41 , R 42 , R 43 , R 44 , R 51 , R 52 , R 61 , and R 62 each represent, independently of one another, a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group, an optionally substituted alkoxy group, an optionally substituted aralkyl group, an optionally substituted aryl group, or an optionally substituted heterocyclic group, and
R 63 represents a halogen atom, a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group, an optionally substituted alkoxy group, an optionally substituted aralkyl group, an optionally substituted aryl group, or an optionally substituted heterocyclic group.

11. The positively chargeable single-layer electrophotographic photosensitive member according to claim 10 , wherein
in the general formulas (3), (4), (5), and (6),
R 31 , R 32 , R 33 , R 34 , R 41 , R 42 , R 43 , R 44 , R 51 , R 52 , R 61 , and R 62 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 5, and
R 63 represents a halogen atom.

12. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , which is used as an image bearing member in an image forming apparatus including a charger that applies direct current voltage to the image bearing member while in contact with the image bearing member.

13. A process cartridge comprising
the positively chargeable single-layer electrophotographic photosensitive member according to claim 1 .

14. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the compound represented by the general formula (1) is a compound represented by formula (HT-1), (HT-2), (HT-3), or (HT-4) shown below.

15. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the first resin is a benzoguanamine resin.

16. The positively chargeable single-layer electrophotographic photosensitive member according to claim 1 , wherein
the photosensitive layer further contains an electron transport material, and
the electron transport material is represented by formula (ET-3) or (ET-4) shown below.

17. An image forming apparatus, comprising:
an image bearing member;
a charger that charges a surface of the image bearing member;
a light exposure section that exposes the charged surface of the image bearing member with light to form an electrostatic latent image on the surface;
a development section that dev

Assignees

• Kyocera Document Solutions Inc

Inventors

• Tsurumi Hiroki
• Miyamoto Eiichi

Classifications

• C07C217/84

  the oxygen atom of at least one of the etherified hydroxy groups being further bound to an acyclic carbon atom · CPC title

• G03G5/0672

  containing two or more methine or polymethine groups · CPC title

• G03G5/0618 Primary

  containing oxygen and nitrogen · CPC title

• G03G5/0564

  Polycarbonates · CPC title

• G03G5/0609

  containing oxygen · CPC title