Electrophotographic photoconductor, electrophotography method using the same, electrophotographic apparatus, electrographic apparatus process cartridge and electrophotographic photoconductor outermost surface layer coating solution

• US 7,018,755 B2
• Filed: 09/23/2003
• Issued: 03/28/2006
• Est. Priority Date: 09/24/2002
• Status: Expired due to Fees

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Suzuki, Yasuo, Kami, Hidetoshi, Shimada, Tomoyuki, Tamoto, Nozomu, Ikegami, Takaaki
• Primary Examiner(s): Dote, Janis L.
• Application Number:
  US10/667,410
• Publication Number:
  US 20040126687A1
• Time in Patent Office: 917 Days
• Field of Search: 430/58.5, 430/58.75, 430/66, 430/74, 430/76, 430/970, 430/73, 430/120, 430/126, 399/116, 399/159, 252/500
• US Class Current: 430/58.5
• CPC Class Codes: G03G 5/06 characterised by the photoconductive material being organic
• CPC Class Codes: G03G 5/0612 containing nitrogen
• CPC Class Codes: G03G 5/147 Cover layers
• CPC Class Codes: G03G 5/14713 Macromolecular material
• CPC Class Codes: G03G 5/14734 Polymers comprising at least one carboxyl radical, e.g. polyacrylic acid, polycrotonic acid, polymaleic acid; Derivatives thereof, e.g. their esters, salts, anhydrides, nitriles, amides
• CPC Class Codes: G03G 5/14747 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: G03G 5/14752 Polyesters
• CPC Class Codes: G03G 5/14756 Polycarbonates
• CPC Class Codes: Y10S 430/103 Radiation sensitive composition or product containing specified antioxidant

Abstract

An electrophotographic photoconductor having at least a photosensitive layer on a conductive support, wherein the electrophotographic photoconductor comprising, in the outermost layer thereof: a filler, an organic compound having an acid value of 10–400 mgKOH/g, and at least one of compounds represented by the following general formulas 1 and 2:
where R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different. R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom. R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms. Ar is a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle. n is an integer in the range 2 to 4, and k, l, m are respectively integers in the range 0 to 3. X is an oxygen atom, or a sulfur atom.

Claims

1. An electrophotographic photoconductor, comprising:

a conductive support; and

a photosensitive layer dispoded above the conductive support,

wherein the electrophotographic photoconductor, in an outermost layer of the electrophotographic photoconductor, comprises;

a filler,

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, and

at least one selected from the group consisting of compounds represented by the following general formulas 1 and 2;

 

where R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different;

R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom;

R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halegen atoms;

Ar is a substituted or unsubstituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle;

n is an integer in the range 2 to 4;

k, l, m are respectively integers in the range 0 to 3; and

X is, in the general formula 1, an oxygen atom, or a sulfur atom.

2. An electrophotographic photoconductor according to claim 1, wherein the organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, is a polycarboxylic acid.

3. An electrophotographic photoconductor according to claim 1, wherein the organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, is at least one selected from the group consisting of a polyester resin, an acrylic resin and a copolymer comprising these structures.

4. An electrophotographic photoconductor according to claim 1, wherein at least one of organic fatty acids is mixed with the organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g.

5. An electrophotographic photoconductor according to claim 1, wherein the filler is at least one of inorganic materials.

6. An electrophotographic photoconductor according to claim 5, wherein the inorganic material is a metal oxide.

7. An electrophotographic photoconductor according to claim 5, wherein the pH of the inorganic material is 5 or more.

8. An electrophotographic photoconductor according to claim 5, wherein the dielectric constant of the inorganic material is 5 or more.

9. An electrophotographic photoconductor according to claim 1, wherein the average first-order particle diameter of the filler is 0.01 μ

m to 0.5 μ

m.

10. An electrophotographic photoconductor according to claim 1, wherein the outermost surface layer is a photosensitive layer.

11. An electrophotographic photoconductor according to claim 10, wherein the photosensitive layer comprises a charge generating layer containing a charge generating material an a charge transport layer containing a charge transport material, the outermost surface layer being the charge transport layer.

12. An electrophotographic photoconductor according to claim 11, wherein the charge transport material is a polymer charge transport material.

13. An electrophotographic photoconductor according to claim 1, wherein the electrophotographic photoconductor comprises a protective layer, the protective layer being the outermost surface layer.

14. An electrophotographic photoconductor according to claim 13, wherein the protective layer contains at least one of charge transport materials.

15. An electrophotographic photoconductor according to claim 14, wherein the charge transport material is a polymer charge transport material.

16. An electrophotographic photoconductor according to claim 1, wherein the outermost surface layer of the photoconductor contains as a binder resin at least one selected from the group consisting of a polycarbonate resin and a polyarylate resin.

17. An electrophotographic photoconductor according to claim 1, wherein the outermost surface layer is formed by coating an outermost surface layer coating solution containing:

a filler;

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g;

at least one selected from the group consisting of compounds represented by the above general formulas 1 and 2; and

an antioxidant.

18. The electrophotographic photoconductor according to claim 17, wherein the antioxidant is one selected from the group consisting of a hydroquinone compound and a hindered amine compound.

19. An electrophotographic photoconductor outermost surface layer coating solution, comprising:

a filler;

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g;

at least one selected from the group consisting of compounds represented by the following general formulas 1 and 2;

 

where R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different;

R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom;

R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms;

Ar is a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle;

n is a integer in the range 2 to 4;

k, l, m are respectively integers in the range 0 to 3; and

X is, in the general formula 1, an oxygen atom, or a sulfur atom; and

an antioxidant.

20. An electrophotographic photoconductor outermost surface layer coating solution according to claim 19, wherein the antioxidant in one selected from the group consisting of a hydroquinone compound and a hindered amine compound.

21. An electrophotographic method, comprising the steps of:

charging an electrophotographic photoconductor;

exposing the charged photoconductor with an imagewise light so as to form an latent electrostatic image thereon;

supplying a developer to the formed latent electrostatic image so that a toner image is formed, thereby visualizing the latent electrostatic image; and

transferring the toner image formed by the developing step to a transfer material,

wherein the toner graphic photoconductor, in an outermost surface layer of the electrophotographic photoconductor, comprises;

a filler,

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, and

at least one selected from the group consisting of compounds represented by the following general formulas 1 and 2;

 

where R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different;

R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom;

R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms;

Ar is a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle;

n is an integer in the range 2 to 4;

k, l, m are respectively integers in the range 0 to 3; and

X is, in the general formula 1, an oxygen atom, or a sulfur atom.

22. An electrophotographic method according to claim 21, wherein in the exposure step the latent electrostatic image is written on the electrophotographic photoconductor by a LD or LED.

23. An electrophotographic apparatus, comprising:

an electrophotographic photoconductor;

a charger configure to uniformly charge a surface of the electrophotographic photoconductor;

an exposure unit configured to expose the charged photoconductor by the charger with an imagewise light so as to form an latent electrostatic image on the photoconductor;

a developing unit configured to supply a developer to the latent electrostatic image so that a toner image is formed, thereby visualizing the latent electrostatic image; and

a transfer unit configured to transfer the formed toner image by the developing unit to a transfer material,

wherein the electrophotographic photoconductor, in an outermost surface layer of the electrophotographic photoconductor, comprises;

a filler,

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, and

at least one selected from the group consisting of compounds represented by the following general formulas 1 and 2;

 

where, in the general formulas 1 and 2, R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different;

R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom;

R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms;

Ar is a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocycle;

n is an integer in the range 2 to 4, and k, l, m are respectively integers in the range 0 to 3; and

X is, in the general formula 1, an oxygen atom, or a sulfur atom.

24. An electrophotographic apparatus according to claim 23, wherein the exposure unit is configured so that the latent electrostatic image is written on the electrophotographic photoconductor by a LD or LED.

25. An electrophotographic process cartridge, comprising:

an electrophotographic photoconductor; and

at least one selected from the group consisting of

a charger configured to uniformly charge a surface of the electrophotographic photoconductor,

a cleaning unit configured to clean the surface of the electrophotographic photoconductor, and

a developing unit configured to supply a developer to a latent electrostatic image formed on the electrophotographic photoconductor so that a toner image is formed, thereby visualizing the latent electrostatic image,

wherein the electrophotographic process cartridge is formed in a one-piece construction such that the electrophotographic process cartridge is freely replaceable from an electrophotographic apparatus, and wherein the electrophotographic photoconductor, in an outermost surface layer of the electrophotographic photoconductor, contains;

a filler,

an organic compound having an acid value of 10 mgKOH/g to 400 mgKOH/g, and

at least one selected from the group consisting of compounds represented by the following formulas 1 and 2;

 

where R¹, R² are substituted or unsubstituted alkyl groups or aromatic hydrocarbon rings, and may be identical or different;

R¹, R² may also be bonded together to form a substituted or unsubstituted heterocycle containing a nitrogen atom;

R³, R⁴, R⁵ are substituted or unsubstituted alkyl or alkoxy groups, or halogen atoms;

Ar is a substituted or unsubstituted aromatic hydrocarbond ring or aromatic heterocycle;

n is an integer in the range 2 to 4;

k, l, m are respectively integers in the range 0 to 3; and

X is, in the general formula 1, an oxygen atom, or a sulfur atom.