Electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10001714-B2
Application number	US-201614996297-A
Country	US
Kind code	B2
Filing date	Jan 15, 2016
Priority date	Sep 25, 2015
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

An electrophotographic photosensitive member includes a conductive base; an organic photosensitive layer disposed on the conductive base, the organic photosensitive layer including a layer that constitutes a surface and contains a charge transport material, a binder resin having a viscosity-average molecular weight less than about 50,000, and silica particles in an amount of about 40% by weight or more; and an inorganic protective layer disposed on the organic photosensitive layer.

First claim

What is claimed is:

1. An electrophotographic photosensitive member comprising:
a conductive base;
an organic photosensitive layer disposed on the conductive base, the organic photosensitive layer including a surface layer that contains a charge transport material, a binder resin having a viscosity-average molecular weight less than 30,000, and silica particles in an amount of 40% by weight or more relative to the weight of the surface layer; and
an inorganic protective layer disposed on the surface layer,
wherein the silica particles have a volume-average particle diameter of 20 nm or more and 200 nm or less, and
a surface roughness of the surface layer is 2.5 nm or less.

2. The electrophotographic photosensitive member according to claim 1 , wherein the organic photosensitive layer includes a charge generation layer and a charge transport layer stacked on the conductive base in that order, the charge transport layer being the surface layer.

3. The electrophotographic photosensitive member according to claim 1 , wherein the silica particles are contained in an amount of 45% by weight or more.

4. The electrophotographic photosensitive member according to claim 1 , wherein the silica particles are contained in an amount of 50% by weight or more.

5. The electrophotographic photosensitive member according to claim 1 , wherein the binder resin contains a bisphenol Z homopolymeric polycarbonate resin.

6. The electrophotographic photosensitive member according to claim 1 , wherein the silica particles are hydrophobic silica particles.

7. A process cartridge detachably attachable to an image forming apparatus, comprising:
the electrophotographic photosensitive member according to claim 1 .

8. An image forming apparatus comprising:
the electrophotographic photosensitive member according to claim 1 ;
a charging unit that charges the electrophotographic photosensitive member;
an electrostatic latent image forming unit that forms an electrostatic latent image on the electrophotographic photosensitive member in a charged state;
a developing unit that develops the electrostatic latent image on the electrophotographic photosensitive member with a developer containing a toner so as to form a toner image;
a transfer unit that transfers the toner image onto a recording medium; and
a cleaning unit that cleans the electrophotographic photosensitive member.

Assignees

• Fuji Xerox Co Ltd

Inventors

• Hirakata Masaki
• Iwanaga Takeshi
• Torigoe Nobuyuki
• Katsuhara Hideya
• KIGOSHI Yoichi
• Imai Takashi
• Mera Fumiaki

Classifications

• G03G5/0507 Primary

  Inorganic compounds · CPC title

• G03G5/0564

  Polycarbonates · CPC title

• G03G5/0596

  Macromolecular compounds characterised by their physical properties · CPC title

• G03G21/18

  using a processing cartridge {, whereby the process cartridge comprises at least two image processing means in a single unit} · CPC title

• G03G5/087

  and being incorporated in an organic bonding material · CPC title