Electrophotographic apparatus

Patent metadata

Field	Value
Publication number	US-10732525-B2
Application number	US-201916387422-A
Country	US
Kind code	B2
Filing date	Apr 17, 2019
Priority date	Apr 25, 2018
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

An electrophotographic apparatus includes an electrophotographic photosensitive member, a charging roller disposed so as to come into contact with the electrophotographic photosensitive member, and a charging device operable to apply only a DC voltage to charge the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a support member, an undercoat layer over the support member, and a photosensitive layer over the undercoat layer and having a plurality of discrete recesses in the surface thereof. The undercoat layer contains zinc oxide particles and a binder resin. The undercoat layer has cavities therein, and the cavities account for 5.00% or less of the volume of the undercoat layer.

First claim

What is claimed is:

1. An electrophotographic apparatus comprising:
an electrophotographic photosensitive member having discrete recesses in the surface thereof;
a charging roller disposed so as to come into contact with the electrophotographic photosensitive member; and
a charging device operable to apply only a DC voltage to the charging roller so as to electrically charge the electrophotographic photosensitive member,
wherein the electrophotographic photosensitive member includes:
a support member,
an undercoat layer over the support member, and
a photosensitive layer over the undercoat layer,
wherein the undercoat layer contains zinc oxide particles and a binder resin, and the undercoat layer has cavities therein, the cavities accounting for 5.00% or less of the volume of the undercoat layer, and
wherein the undercoat layer has thickness of 25.0 μm or more, and wherein a volume average particle size of the zinc oxide particles is 30 nm or more and 50 nm or less.

2. The electrophotographic apparatus according to claim 1 , wherein the cavities in the undercoat layer account for 0.05% or more of the volume of the undercoat layer.

3. The electrophotographic apparatus according to claim 1 , wherein the cavities in the undercoat layer account for 0.46% to 1.99% of the volume of the undercoat layer.

4. The electrophotographic apparatus according to claim 1 , wherein the recesses have a depth of 3.0 μm or less.

5. The electrophotographic apparatus according to claim 1 , wherein the photosensitive layer includes a charge generating layer and a charge transport layer, and wherein the total thickness of the charge transport layer and layers overlying the charge transport layer is 15.0 μm or more.

Assignees

• Canon Kk

Inventors

• Shimada Tsuyoshi
• Tanabe Kan
• Mitsuda Haruhiko

Classifications

• G03G5/047 Primary

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

• G03G15/0266

  Arrangements for controlling the amount of charge · CPC title

• G03G5/142

  Inert intermediate layers · CPC title

• G03G5/0622

  Heterocyclic compounds · CPC title

• G03G5/144

  comprising inorganic material · CPC title