Electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10241428-B2
Application number	US-201715667690-A
Country	US
Kind code	B2
Filing date	Aug 3, 2017
Priority date	Aug 10, 2016
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The photosensitive layer has a scratch resistance depth of no greater than 0.50 μm.

First claim

What is claimed is:

1. An electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer as a single-layer, wherein
the photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin,
the photosensitive layer has a scratch resistance depth of no greater than 0.50 μm,
the scratch resistance depth of the photosensitive layer representing a hardness of the photosensitive layer containing the binder resin at a ratio of a mass of the binder resin relative to a total mass of the photosensitive layer of at least 0.47 and no greater than 0.60, the binder resin including a polyarylate resin represented by a general formula (1) shown below,

where, in the general formula (1),
kr and kt each represent, independently of one another, 2 or 3,
r+s+t+u=100,
r+t=s+u, and
r, s, t, and u each represent, independently of one another, a number of at least 1, s/(s+u) is greater than 0.00 and no greater than 0.90, one of X and Y represents a divalent group represented by a chemical formula (1-1), and the other of X and Y represents a divalent group represented by a chemical formula (1-2):

2. The electrophotographic photosensitive member according to claim 1 , wherein
in the general formula (1),
r, s, t, and u each represent, independently of one another, a number of at least 1,
s/(s+u) is greater than 0.00 and no greater than 0.90, and
s and u are numbers different from each other.

3. The electrophotographic photosensitive member according to claim 1 , wherein
the electron transport material includes a compound represented by general formula (ETM1) shown below:

where, in the general formula (ETM1), R 1 and R 2 each represent, independently of one another, an alkyl group having 1 to 6 carbon atoms.

4. 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 the general formula (HTM1),
R 21 , R 22 , R 23 , R 24 , R 25 , and R 26 each represent, independently of one another, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
a, b, e, and f each represent, independently of one another, an integer of at least 0 and no greater than 5, and
c and d each represent, independently of one another, an integer of at least 0 and no greater than 4.

5. A process cartridge comprising the electrophotographic photosensitive member according to claim 1 .

6. An image forming apparatus comprising the electrophotographic photosensitive member according to claim 1 , a charger, an exposure section, a developing device, and a transfer section, wherein
the charger is configured to positively charge a surface of the electrophotographic photosensitive member,
the exposure section is configured to expose the charged surface of the electrophotographic photosensitive member to form an electrostatic latent image on the surface of the electrophotographic photosensitive member,
the developing device is configured to develop the electrostatic latent image into a toner image,
the transfer section is configured to transfer the toner image from the electrophotographic photosensitive member to a recording medium, and
the electrophotographic photosensitive member is in contact with the recording medium during the transfer section transferring the toner image from the electrophotographic photosensitive member to the recording medium.

7. The image forming apparatus according to claim 6 , wherein
the developing device develops the electrostatic latent image into the toner image while in contact with the electrophotographic photosensitive member.

8. The image forming apparatus according to claim 6 , wherein
the developing device cleans the surface of the electrophotographic photosensitive member.

9. The image forming apparatus according to claim 6 , wherein
the charger is a charging roller.

10. An electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer as a single-layer, wherein
the photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin,
the photosensitive layer has a scratch resistance depth of no greater than 0.50 μm, the scratch resistance depth of the photosensitive layer representing a hardness of the photosensitive layer containing the binder resin at a ratio of a mass of the binder resin relative to a total mass of the photosensitive layer of at least 0.47 and no greater than 0.60, the binder resin including a polyarylate resin represented by chemical formula (R-1), (R-2), (R-3), (R-4), (R-5), (R-6), (R-7), or (R-8) shown below:

Assignees

• Kyocera Document Solutions Inc

Inventors

• Shimizu Tomofumi
• Maruo Keiji

Classifications

• G03G5/04 Primary

  Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor · CPC title

• G03G5/056

  Polyesters · CPC title

• G03G5/047

  characterised by the charge-generation layers or charge transport layers {(G03G5/0433 and G03G5/0436 take precedence)} · CPC title

• G03G5/0596 Primary

  Macromolecular compounds characterised by their physical properties · CPC title

• G03G5/0609

  containing oxygen · CPC title