Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

Patent metadata

Field	Value
Publication number	US-10935898-B2
Application number	US-201916655494-A
Country	US
Kind code	B2
Filing date	Oct 17, 2019
Priority date	Oct 17, 2018
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

An electrophotographic photosensitive member includes a support, an undercoat layer, a photosensitive layer, and a surface layer, the undercoat layer containing a binder resin and strontium titanate particles, the surface layer being a cured film of a composition containing at least one compound selected from a guanamine compound and a melamine compound, and a charge transport material having at least one substituent selected from —OH, —OCH3, —NH2, —SH, and —COOH.

First claim

What is claimed is:

1. An electrophotographic photosensitive member, comprising:
a support;
an undercoat layer;
a photosensitive layer; and
a surface layer,
the undercoat layer containing a binder resin and strontium titanate particles,
the surface layer being a cured film of a composition containing at least one compound selected from the group consisting of a guanamine compound and a melamine compound, and a charge transport material having at least one substituent selected from the group consisting of —OH, —OCH 3 , —NH 2 , —SH, and —COOH,
wherein in a cross-sectional backscattered electron image of the undercoat layer captured using a scanning electron microscope at an acceleration voltage of 2.0 kV, a region originating from the strontium titanate particles has an area of 0.001 μm 2 or more and 0.35 μm 2 or less, and the area of the region originating from the strontium titanate particles is 50% or more and 90% or less of an area of a region originating from the binder resin.

2. The electrophotographic photosensitive member according to claim 1 , wherein the guanamine compound is one selected from the group consisting of a compound represented by general formula (A) and its multimer:

where in general formula (A), R 1 is an alkyl group having 1 or more and 10 or less carbon atoms, a phenyl group having 6 or more and 10 or less carbon atoms, or an alicyclic hydrocarbon group having 4 or more and 10 or less, R 2 to R 5 are each independently a hydrogen atom or —CH 2 —O—R 6 , and where R 6 is a hydrogen atom or an alkyl group having 1 or more and 10 or less carbon atoms.

3. The electrophotographic photosensitive member according to claim 1 , wherein the melamine compound is one selected from the group consisting of a compound represented by general formula (B) and its multimer:

where in general formula (B), R 6 to R 11 are each independently a hydrogen atom, —CH 2 —OH, —CH 2 —O—R 12 , or —O—R 12 , where R 12 is an alkyl group having 1 or more and 5 or less.

4. The electrophotographic photosensitive member according to claim 1 , wherein in the composition, an amount of the at least one compound selected from the group consisting of the guanamine compound and the melamine compound is 0.1% or more by mass and 50.0% or less by mass based on an amount of the charge transport material.

5. A process cartridge attachable to and detachable from a main body of an electrophotographic apparatus, comprising:
an electrophotographic photosensitive member; and
at least one unit selected from the group consisting of a charging unit, a developing unit, a transfer unit, and a cleaning unit, the process cartridge integrally supporting the electrophotographic photosensitive member and the at least one unit,
wherein the electrophotographic photosensitive member comprises:
a support;
an undercoat layer;
a photosensitive layer; and
a surface layer,
wherein the undercoat layer contains a binder resin and strontium titanate particles, and the surface layer is a cured film of a composition containing at least one compound selected from the group consisting of a guanamine compound and a melamine compound, and a charge transport material having at least one substituent selected from the group consisting of —OH, —OCH 3 , NH 2 , —SH, and —COOH, and
wherein in a cross-sectional backscattered electron image of the undercoat layer captured using a scanning electron microscope at an acceleration voltage of 2.0 kV, a region originating from the strontium titanate particles has an area of 0.001 μm 2 or more and 0.35 μm 2 or less, and the area of the region originating from the strontium titanate particles is 50% or more and 90% or less of an area of a region originating from the binder resin.

6. An electrophotographic apparatus, comprising:
an electrophotographic photosensitive member;
a charging unit;
an exposure unit;
a developing unit; and
a transfer unit,
wherein the electrophotographic photosensitive member comprises:
a support;
an undercoat layer;
a photosensitive layer; and
a surface layer, and
wherein the undercoat layer contains a binder resin and strontium titanate particles, and the surface layer is a cured film of a composition containing at least one compound selected from the group consisting of a guanamine compound and a melamine compound, and a charge transport material having at least one substituent selected from the group consisting of —OH, —OCH 3 , —NH 2 , SH, and —COOH, and
wherein in a cross-sectional backscattered electron image of the undercoat layer captured using a scanning electron microscope at an acceleration voltage of 2.0 kV, a region originating from the strontium titanate particles has an area of 0.001 μm 2 or more and 0.35 μm 2 or less, and the area of the region originating from the strontium titanate particles is 50% or more and 90% or less of an area of a region originating from the binder resin.

Assignees

• Canon Kk

Inventors

• Kuroiwa Ikuyo
• Takizawa Kumiko
• Shimada Tsuyoshi
• Tanabe Kan
• Mitsuda Haruhiko
• Ueno Takanori
• Ikezue Tatsuya
• Kitamura Wataru

Classifications

• G03G5/144

  comprising inorganic material · CPC title

• G03G5/14

  Inert intermediate or cover layers for charge-receiving layers (for photoconductive, charge-generation or charge-transporting layers G03G5/04) · CPC title

• G03G5/14765

  Polyamides; Polyimides · CPC title

• G03G5/14769

  Other polycondensates comprising nitrogen atoms with or without oxygen atoms in the main chain · CPC title

• G03G5/14791 Primary

  Macromolecular compounds characterised by their structure, e.g. block polymers, reticulated polymers, or by their chemical properties, e.g. by molecular weight or acidity · CPC title