Electrophotographic photoreceptor, and image forming device and electrophotographic photoreceptor cartridge using the same member cartridge

1. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, wherein

said photosensitive layer comprises a polyester resin comprising a hydrazone compound and having a repeating structural unit represented by the formula (1):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

2. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, wherein

said photosensitive layer comprises a layer including a polyester resin comprising a repeating structural unit represented by the formula (1) and a charge transport material, and

said charge transport material comprises only a charge transport material containing substantially no unsaturated bond other than in an aromatic ring:

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

3. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, wherein

said photosensitive layer comprises a polyester resin comprising a repeating structural unit represented by the formula (1) and a diamine compound represented by the formula (2):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted , X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms; and

wherein Ar 5 to Ar 8 each represents, independently of each other, an aryl group which may have a substituent with 8 or less carbon atoms, and Ar 9 and Ar 10 each represents, independently of each other, an arylene group which may be substituted.

4. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, wherein

said photosensitive layer comprises a polyester resin containing an antioxidant and having a repeating structural unit represented by the formula (1):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

5. The electrophotographic photoreceptor according to claim 4 , wherein said antioxidant is a phenolic antioxidant.

6. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, wherein

said photosensitive layer comprises a polyester resin as a first resin comprising a repeating structural unit represented by the formula (1) and at least another resin as a second resin selected from the group consisting of a polyester resin having a different structure from said first resin and a polycarbonate resin, wherein

at least either said first resin or said second resin comprises a repeating structural unit represented by the formula (3):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substitute , X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms; and

wherein R 1 and R 2 each represents, independently of each other, a hydrogen atom or an alkyl group, R 3 and R 4 each represents, independently of each other, an alkyl group, and m and n each represents, independently of each other, an integer selected from 1 to 4.

7. The electrophotographic photoreceptor according to claim 6 , wherein said second resin is a polycarbonate resin.

8. The electrophotographic photoreceptor according to claim 6 , wherein the repeating structural unit represented by the formula (3) is a repeating structural unit represented by the formula (3′):

9. The electrophotographic photoreceptor according to claim 8 , wherein the weight ratio of the repeating structural unit represented by the formula (3′) in the total weight of said first resin and said second resin is from 1 weight % to 45 weight %.

10. The electrophotographic photoreceptor according to claim 8 , wherein said second resin is a polycarbonate resin.

11. The electrophotographic photoreceptor according to claim 10 , wherein the second resin comprises repeating structural unit of the formula (3″), and the weight ratio of the repeating structural unit represented by the formula (3″) contained in said polycarbonate resin is 70 weight % or more of said polycarbonate resin:

12. An electrophotographic photoreceptor of a positive charge type comprising a monolayer type photosensitive layer on an electroconductive support, wherein said monolayer type photosensitive layer comprises a polyester resin comprising a repeating structural unit represented by the formula (1):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

13. An electrophotographic photoreceptor cartridge comprising:

the electrophoto graphic photoreceptor according to claim 1 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and a means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

14. An electrophotographic photoreceptor cartridge comprising:

the electrophotographic photoreceptor according to claim 2 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

15. An electrophotographic photoreceptor cartridge comprising:

the electrophotographic photoreceptor according to claim 3 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

16. An electrophotographic photoreceptor cartridge comprising:

the electrophotographic photoreceptor according to claim 4 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

17. An electrophotographic photoreceptor cartridge comprising:

the electrophotographic photoreceptor according to claim 6 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

18. An electrophotographic photoreceptor cartridge comprising:

the electrophotographic photoreceptor according to claim 12 and

at least one means selected from the group consisting of means for charging said electrophotographic photoreceptor, means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon, and means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

19. An image forming device comprising:

the electrophotographic photoreceptor according to claim 1 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

20. An image forming device comprising:

the electrophotographic photoreceptor according to claim 2 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

21. An image forming device comprising:

the electrophotographic photoreceptor according to claim 3 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

22. An image forming device comprising:

the electrophotographic photoreceptor according to claim 4 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

23. An image forming device comprising:

the electrophotographic photoreceptor according to claim 6 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

24. An image forming device comprising:

the electrophotographic photoreceptor according to claim 12 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor to form an electrostatic latent image thereon,

means for developing the electrostatic latent image with toner, and

means for transferring the toner to a transfer target.

25. An image forming device comprising at least an electrophotographic photoreceptor and a toner, wherein

the photosensitive layer of said electrophotographic photoreceptor comprises a polyester resin containing a repeating structural unit represented by formula (1) below, and

the average degree of circularity of said toner, measured by a flow particle image analyzer, is 0.940 or larger and 1.000 or smaller:

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may have a substituent, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

26. An image forming device according to claim 25 , wherein said toner is produced in an aqueous medium.

27. An image forming device according to claim 25 , wherein said toner has a resin-coating layer.

28. An image forming device according to claim 27 , wherein said toner contains polysiloxane wax in said resin-coating layer.

29. An image forming device according to claim 25 , wherein said toner contains a paraffin wax.

30. An electrophotographic photoreceptor for an image forming device of which an exposure part for forming an electrostatic latent image emits a monochromatic light having an exposure wavelength of 380 nm to 500 nm,

the photoreceptor comprising at least a photosensitive layer which comprises a polyester resin comprising a repeating structural unit represented by the formula (1):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substituted, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

31. An electrophotographic photoreceptor comprising at least a photosensitive layer on an electroconductive support, said photosensitive layer comprises a charge transport layer,

wherein said charge transport layer has a transmittance of 70% or larger in the wavelength region of 400 nm to 500 nm, and

said charge transport layer comprises a polyester resin, said polyester resin comprises a repeating structural unit represented by the formula (1):

wherein Ar 1 to Ar 4 each represents, independently of each other, an arylene group which may be substitued, X 1 represents a bivalent group or a single bond, and X 2 represents a bivalent group with 3 or less atoms.

32. An image forming device comprising:

the electrophotographic photoreceptor according to claim 30 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor with a monochromatic light having an exposure wavelength of 380 nm to 500 nm to form an electrostatic latent image thereon, and

means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.

33. An image forming device comprising:

the electrophotographic photoreceptor according to claim 31 ,

means for charging said electrophotographic photoreceptor,

means for exposing said charged electrophotographic photoreceptor with a monochromatic light having an exposure wavelength of 380 nm to 500 nm to form an electrostatic latent image thereon, and

means for developing the electrostatic latent image formed on said electrophotographic photoreceptor.