Image forming apparatus, image forming method, process cartridge, photoconductor and method of preparing photoconductor

• US 20020160287A1
• Filed: 02/20/2002
• Published: 10/31/2002
• Est. Priority Date: 02/20/2001
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Aruga, Tamotsu, Kabata, Toshiyuki, Miyamoto, Yuka
• Granted Patent: US 6,699,631 B2
• Time in Patent Office: Days
• US Class Current: 430/56
• CPC Class Codes: G03G 5/005 Materials for treating the recording members, e.g. for cleaning, reactivating, polishing
• CPC Class Codes: G03G 5/04 Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor

Abstract

An image forming apparatus including a photoconductor, and an exposing device for irradiating a surface of the photoconductor imagewise with a coherent light to form an electrostatic latent image thereon. The surface of the photoconductor has such roughness as to provide I(S) of at least 3.0×10⁻³, wherein I(S) is given by the following equations: $I\left(S\right)=\left(\frac{1}{N}\right)\sum _{n=0}^{N-1}\left\{S\left(\frac{n}{N·\Delta t}\right)\right\}$$S\left(\frac{n}{N·\Delta t}\right)=\frac{1}{N}·{X\left(\frac{n}{N·\Delta t}\right)}^2$$X\left(\frac{n}{N·\Delta t}\right)=\sum _{m=0}^{N-1}x\left(m·\Delta t\right)\exp \left(-\mathrm{2}\pi ·\frac{n}{N·\Delta t}·m·\Delta t\right)$

wherein N is a number of samples obtained from a sectional curve of the surface of the photoconductor and is 2^p where p is an integer, Δt is a sampling interval, in μm, at which the N-number of the samples are sampled, x(t) is a height of the sectional curve, in μm, of a sample at a position t in the preset length, and n and m are integers. The sectional curve is as obtained by measuring a profile of the surface through a preset length N·Δt.

Claims

1. An image forming apparatus comprising a photoconductor having a photoconductive layer provided on a support, and an exposing device for irradiating a surface of said photoconductor imagewise with a coherent light to form an electrostatic latent image thereon, the surface of said photoconductor having such characteristics as to provide I(S) of at least 3.0×

10<sup>−

3</sup> wherein I(S) is given by the following equations;

2. An image forming apparatus as claimed in claim 1, wherein I(S) ranges from 5.0×

10<sup>−

3</sup> to 150.0×

10<sup>−

3</sup>.

3. An image forming apparatus as claimed in claim 1, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

4. An image forming apparatus as claimed in claim 1, wherein a ratio of I′

(S) to I(S) satisfies with the following condition;

I′

(S)/I(S)<

0.35

where

5. An image forming apparatus as claimed in claim 1, wherein particles are exposed from the surface of the photoconductor.

6. An image forming apparatus as claimed in claim 5, wherein said photoconductive layer comprises a charge transporting layer and wherein the particles have a refractive index which is 0.8 to 1.2 times that of the charge transporting layer.

7. An image forming apparatus as claimed in claim 6, wherein the particles exposed from the surface of the photoconductor has a particle diameter in the range of 0.01-1.00 μ

m.

8. An image forming apparatus as claimed in claim 1, wherein said photoconductive layer having a thickness of 15 μ

m or less.

9. An image forming apparatus as claimed in claim 1, wherein said photoconductive layer has an interface on the side of said support, said interface having such characteristics as to provide I(S) of at least 1.5×

10<sup>−

3</sup> wherein I(S) is given by the following equations;

10. An image forming apparatus as claimed in claim 9, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

11. An image forming apparatus as claimed in claim 1, wherein said support has a surface on which said photoconductive layer is provided, said surface of said support having such characteristics as to provide I(S) of at least 3.0×

10<sup>−

3</sup>, wherein I(S) is given by the following equations;

12. An image forming apparatus as claimed in claim 11, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

13. An image forming apparatus as claimed in claim 1, wherein said coherent light has a wavelength of 700 nm or less.

14. An image forming apparatus as claimed in claim 1, wherein said exposing device is of a type which outputs an image by a multi-level gradation reproducing system.

15. An image forming apparatus as claimed in claim 1, and configured to produce an image with a resolution of 1000 dpi or higher.

16. An image forming apparatus as claimed in claim 1, further comprising means for applying a lubricant to the surface of the photoconductor.

17. An image forming apparatus as claimed in claim 16, wherein said lubricant is metal soap.

18. An image forming apparatus as claimed in claim 17, wherein said metal soap is zinc stearate.

19. An image forming apparatus as claimed in claim 1, and constructed into a full color image forming machine.

20. An image forming apparatus as claimed in claim 19, comprising a developing unit for developing the latent image with a developer to form a toner image on the photoconductor, an intermediate transfer member to receive the toner image from the photoconductor, and an image receiving medium to receive the toner image from the intermediate transfer member.

21. An image forming apparatus as claimed in claim 20, wherein

22. An image forming apparatus as claimed in claim 19, comprising a plurality of photoconductors for forming a plurality of color toner images, respectively, an intermediate transfer member to receive the color toner images from respective photoconductors to form stacked color toner images, and an image receiving medium to receive the stacked color toner images from the intermediate transfer member.

23. An image forming apparatus as claimed in claim 22, wherein said intermediate transfer member is an elastic belt.

25. An image forming method as claimed in claim 24, wherein I(S) ranges from 5.0×

10<sup>−

3</sup> to 150.0×

10<sup>−

3</sup>.

26. An image forming method as claimed in claim 24, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

27. An image forming method as claimed in claim 24, wherein a ratio of I′

(S) to I(S) satisfies with the following condition;

I′

(S)/I(S)≦

0.35

where

28. An image forming method as claimed in claim 24, wherein particles are exposed from the surface of the photoconductor.

29. An image forming method as claimed in claim 24, wherein said photoconductive layer comprises a charge transporting layer and wherein the particles have a refractive index which is 0.8 to 1.2 times that of the charge transporting layer.

30. An image forming method as claimed in claim 29, wherein the particles exposed from the surface of the photoconductor has a particle diameter in the range of 0.01-1.00 μ

m.

31. An image forming method as claimed in claim 24, wherein said photoconductive layer having a thickness of 15 μ

m or less.

32. An image forming method as claimed in claim 24, wherein said photoconductive layer has an interface on the side of said support, said interface having such characteristics as to provide I(S) of at least 1.5×

10<sup>−

3</sup>, wherein I(S) is given by the following equations;

33. An image forming method as claimed in claim 32, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

34. An image forming method as claimed in claim 24, wherein said support has a surface on which said photoconductive layer is provided, said surface of said support having such characteristics as to provide I(S) of at least 3.0×

10<sup>−

3</sup>, wherein I(S) is given by the following equations;

35. An image forming method as claimed in claim 34, wherein Δ

t ranges from 0.01 to 50.00 μ

m and N is at least 2048.

37. A process cartridge freely detachable from an image forming apparatus, comprising a photoconductor according to claim 36, and at least one means selected from the group consisting of charging means, image exposure means having a coherent light source, developing means, image transfer means, and cleaning means.

24. An image forming method wherein a coherent light is irradiated on a photoconductor having a photoconductive layer provided on a support to form an electrostatic latent image thereon, the surface of said photoconductor having such characteristics as to provide I(S) of at least 3.0×

10<sup>−

3</sup> wherein I(S) is given by the following equations;

36. A photoconductor comprising a support, and a photoconductive layer provided on said support, said photoconductor having such surface characteristics as to provide I(S) of at least 3.0×

10<sup>−

3</sup>, wherein I(S) is given by the following equations;

38. A method of producing a photoconductor comprising forming a photoconductive layer on a support such that said photoconductor has surface characteristics providing I(S) of at least 3.0×

10<sup>−

3</sup> wherein I(S) is given by the following equations;