1. A method for preparing a titanium dioxide paste, comprising steps of:
adding a titanium dioxide nanoparticle to water, alcohol, or a mixed solvent thereof (Step 1);
dispersing the resultant mixture formed in Step 1 with ultrasound (Step 2);
adding a titanium dioxide precursor to the dispersed solution formed in Step 2 (Step 3); and
stirring the resultant mixture formed in Step 3 (Step 4).
2. The preparation method according to claim 1, wherein a dye or a metal precursor is also added in Step 1.
3. The preparation method according to claim 2, wherein a dye is added in Step 1 and Step 1 comprises the steps of:
preparing a dye solution by dissolving the dye in alcohol (Step a1);
preparing a mixed solution by adding water to the dye solution (Step b1); and
adding a titanium dioxide nanoparticle to the mixed solution (Step c1).
4. The preparation method according to claim 2, wherein a metal precursor is added in Step 1 and Step 1 comprises the steps of:
preparing a metal precursor solution by dissolving a metal precursor in alcohol (Step a2);
preparing a mixed solution by adding water to the metal precursor solution (Step b2); and
adding a titanium dioxide nanoparticle to the mixed solution (Step c2).
5. The preparation method according to claim 2, wherein the dye is a ruthenium-based organo-metallic compound selected from the group consisting of N3, N749,and Z907; an organic compound selected from the group consisting of coumarin, porphyrin, xanthine, riboflavin, triphenyl methane, D205, NKX-2311, and NKX-2677; or a quantum dot inorganic compound selected from the group consisting of InP, CdSe, CdS, CdTe, PbS, and PbSe.
6. The preparation method according to claim 2, wherein the concentration of the dye is 0.3 to 3 mM.
7. The preparation method according to claim 2, wherein the metal precursor is gold (Au), platinum (Pt), or palladium (Pd).
8. The preparation method according to claim 2, wherein the concentration of the metal precursor is 0.3 to 10 mM.
9. The preparation method according to claim 1, wherein the alcohol is ethanol, methanol, propanol, or butanol.
10. The preparation method according to claim 1, wherein the amount of the titanium dioxide nanoparticle is 7 to 13% of the total amount of the titanium dioxide paste by weight.
11. The preparation method according to claim 1, wherein Step 2 is performed by repeating 5 to 15 times the process of ultrasonic treatment of the resultant mixture formed in Step 1 for 5-15 minutes followed by cooling for 1-5 minutes.
12. The preparation method according to claim 1, wherein the titanium dioxide precursor is titanium alkoxide, titanium chloride (TiCl4), or a combination thereof.
13. The preparation method according to claim 12, wherein the titanium alkoxide is titanium isopropoxide (TIPP), titanium methoxide, titanium ethoxide, titanium tetrabutoxide, titanium tetra-isobutoxide, titanium tetra-tert butoxide, or a combination thereof.
14. The preparation method according to claim 1, wherein the amount of the titanium dioxide precursor is 0.05 to 0.2 mol per 1 mol of the titanium dioxide nanoparticle.
15. The preparation method according to claim 1, wherein the amount of water is 2 to 4 mol per 1 mol of the titanium dioxide precursor.
16. The preparation method according to claim 1, wherein of Step 4 is performed for 3 to 7 hours.
17. A titanium dioxide paste prepared by the method of claim 1.
18. The titanium dioxide paste according to claim 17, wherein the titanium dioxide paste is used for a dye sensitized solar cell.
19. A method for preparing an electrode for a dye sensitized solar cell, comprising steps of:
preparing an electrode-treated substrate (Step 1);
coating the top of the electrode with a titanium dioxide paste of claim 17 (Step 2);
forming a titanium dioxide layer by curing the coated substrate at 100 to 140\xb0 C. (Step 3); and
adsorbing dye on the titanium dioxide layer (Step 4).
20. A method for preparing an electrode for a dye sensitized solar cell, comprising steps of:
preparing a dye solution by dissolving dye in alcohol;
preparing a mixed solution by adding water to the dye solution;
adding a titanium dioxide nanoparticle to the mixed solution to form a first mixture;
dispersing the first mixture with ultrasound;
adding a titanium dioxide precursor to the dispersed solution to form a second mixture;
stirring the second mixture to form titanium dioxide paste;
preparing an electrode-treated substrate;
coating the top of the electrode with the titanium dioxide paste; and
forming a titanium dioxide layer by curing the coated substrate at 100\xb0 C. to 140\xb0 C.
21. A method for preparing an electrode for a dye sensitized solar cell, comprising steps of:
preparing a metal precursor solution by dissolving the metal precursor in alcohol;
preparing a mixed solution by adding water to the metal precursor solution;
adding a titanium dioxide nanoparticle to the mixed solution to form a first mixture;
dispersing the first mixture with ultrasound;
adding a titanium dioxide precursor to the dispersed solution to form a second mixture;
stirring the second mixture to form titanium dioxide paste;
preparing an electrode-treated substrate;
coating the top of the electrode with the titanium dioxide paste;
forming a titanium dioxide layer by curing the coated substrate at 100\xb0 C. to 140\xb0 C.;and
adsorbing dye on the titanium dioxide layer.
22. The preparation method according to claim 21, further comprising a step of reducing the metal precursor to a metal after coating the top of the electrode with the titanium dioxide paste.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed as new and desired to be secured by Letters Patent of the United States is:
1. A photoreceptor comprising an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, and wherein the photosensitive layer further comprises at least one ion selected from the group consisting of K, Na, NO3, HCOO, NO2, Cl, Br, and NH4.
2. The photoreceptor according to claim 1, wherein the organic pigment comprises a titanyl phthalocyanine.
3. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
4. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
5. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
6. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.10.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
7. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a K ion in an amount not greater than 50 ppm.
8. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a Na ion in an amount not greater than 200 ppm.
9. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a NO3 ion in an amount not greater than 50 ppm.
10. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a HCOO ion in an amount not greater than 100 ppm.
11. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a NO2 ion in an amount not greater than 50 ppm.
12. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a Cl ion in an amount not greater than 100 ppm.
13. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a Br ion in an amount not greater than 50 ppm.
14. The photoreceptor according to claim 2, wherein the titanyl phthalocyanine comprises a NH4 ion in an amount of from 10 ppm to 300 ppm.
15. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a K ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
16. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a Na ion in an amount not greater than 200 ppm relative to total amount of the organic pigment.
17. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a NO3 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
18. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a HCOO ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
19. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a NO2 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
20. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a Cl ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
21. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a Br ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
22. The photoreceptor according to claim 1, wherein the photosensitive layer comprises a NH4 ion in an amount of from 10 ppm to 300 ppm relative to total amount of the organic pigment.
23. The photoreceptor according to claim 1, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
24. The photoreceptor according to claim 23, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
25. A photoreceptor comprising an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, and wherein the photosensitive layer further comprises one or more water-soluble inorganic salts, and wherein the one or more water-soluble inorganic salts are present in the photosensitive layer in an amount not greater than 1000 ppm relative to total amount of the organic pigment.
26. The photoreceptor according to claim 25, wherein the organic pigment comprises a titanyl phthalocyanine.
27. The photoreceptor according to claim 26, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
28. The photoreceptor according to claim 26, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
29. The photoreceptor according to claim 26, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
30. The photoreceptor according to claim 26, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.10.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
31. The photoreceptor according to claim 25, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
32. The photoreceptor according to claim 31, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
33. An electrophotographic image forming method comprising:
charging a surface of a photoreceptor;
irradiating the photoreceptor with light to form an electrostatic latent image on a surface of the photoreceptor;
developing the electrostatic latent image with a toner to form a toner image on the surface of the photoreceptor; and
transferring the toner image onto a receiving material, wherein the photoreceptor comprises an electroconductive substrate and a photosensitive layer on the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, and wherein the photosensitive layer further comprises at least one ion selected from the group consisting of K, Na, NO3, HCOO, NO2, Cl, Br, and NH4.
34. The image forming method according to claim 33, wherein the organic pigment comprises a titanyl phthalocyanine.
35. The image forming method according to claim 34, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
36. The image forming method according to claim 34, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
37. The image forming method according to claim 34, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
38. The image forming method according to claim 34, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
39. The image forming method according to claim 33, wherein the photosensitive layer comprised a K ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
40. The image forming method according to claim 33, wherein the photosensitive layer comprises a Na ion in an amount not greater than 200 ppm relative to total amount of the organic pigment.
41. The image forming method according to claim 33, wherein the photosensitive layer comprises a NO3 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
42. The image forming method according to claim 33, wherein the photosensitive layer comprises a HCOO ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
43. The image forming method according to claim 33, wherein the photosensitive layer comprises a NO2 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
44. The image forming method according to claim 33, wherein the photosensitive layer comprises a Cl ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
45. The image forming method according to claim 33, wherein the photosensitive layer comprises a Br ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
46. The image forming method according to claim 33, wherein the photosensitive layer comprises a NH4 ion in an amount of from 10 to 300 ppm relative to total amount of the organic pigment.
47. The image forming method according to claim 33, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
48. The image forming method according to claim 47, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
49. An electrophotographic image forming method comprising:
charging a surface of a photoreceptor;
irradiating the photoreceptor with light to form an electrostatic latent image on a surface of the photoreceptor;
developing the electrostatic latent image with a toner to form a toner image on the surface of the photoreceptor; and
transferring the toner image onto a receiving material, wherein the photoreceptor comprising an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, wherein the photosensitive layer further comprises one or more water-soluble inorganic salts, and wherein the one or more water-soluble inorganic salts are present in the photosensitive layer in an amount not greater than 1000 ppm relative to total amount of the organic pigment.
50. The image forming method according to claim 49, wherein the organic pigment comprises a titanyl phthalocyanine.
51. The image forming method according to claim 50, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
52. The image forming method according to claim 50, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
53. The image forming method according to claim 50, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
54. The image forming method according to claim 50, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
55. The image forming method according to claim 49, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
56. The image forming method according to claim 55, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
57. An electrophotographic image forming apparatus comprising:
a photoreceptor;
a charger which charges a surface of the photoreceptor;
a light irradiating device which irradiates the surface of the photoreceptor with light to form an electrostatic latent image on the surface of the photoreceptor;
a developing device which develops the electrostatic latent image with a toner to form a toner image on the surface of the photoreceptor; and
a transfer device which transfers the toner image on the photoreceptor to a receiving material,
wherein the photoreceptor comprises an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, and wherein the photosensitive layer further comprises at least one ion selected from the group consisting of K, Na, NO3, HCOO, NO2, Cl, Br, and NH4.
58. The image forming apparatus according to claim 57, wherein the organic pigment comprises a titanyl phthalocyanine.
59. The image forming apparatus according to claim 58, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
60. The image forming apparatus according to claim 58, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
61. The image forming apparatus according to claim 58, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
62. The image forming apparatus according to claim 58, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
63. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a K ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
64. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a Na ion in an amount not greater than 200 ppm relative to total amount of the organic pigment.
65. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a NO3 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
66. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a HCOO ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
67. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a NO2 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
68. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a Cl ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
69. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a Br ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
70. The image forming apparatus according to claim 57, wherein the photosensitive layer comprises a NH4 ion in an amount of from 10 to 300 ppm relative to total amount of the organic pigment.
71. The image forming apparatus according to claim 57, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
72. The image forming apparatus according to claim 71, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
73. The image forming apparatus according to claim 57, wherein the charger charges the photoreceptor while contacting the surface of the photoreceptor.
74. The image forming apparatus according to claim 57, wherein the charger charges the photoreceptor while close to, but not touching, the surface of the photoreceptor.
75. The image forming apparatus according to claim 57, wherein the charger charges the photoreceptor while applying a DC voltage overlapped with an AC voltage to the surface of the photoreceptor.
76. The image forming apparatus according to claim 57, wherein the light irradiating device comprises a light source selected from the group consisting of laser diodes and light emitting diodes.
77. An electrophotographic image forming apparatus comprising:
a photoreceptor;
a charger which charges a surface of the photoreceptor;
a light irradiating device which irradiates the surface of the photoreceptor with light to form an electrostatic latent image on the surface of the photoreceptor;
a developing device which develops the latent image with a toner to form a toner image on the surface of the photoreceptor; and
a transfer device which transfers the toner image on the photoreceptor to a receiving material,
wherein the photoreceptor comprising an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, wherein the photosensitive layer further comprises one or more water-soluble inorganic salts, and wherein the one or more water-soluble inorganic salts are present in the photosensitive layer in an amount not greater than 1000 ppm relative to total amount of the organic pigment.
78. The image forming apparatus according to claim 77, wherein the organic pigment comprises a titanyl phthalocyanine.
79. The image forming apparatus according to claim 78, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
80. The image forming apparatus according to claim 78, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
81. The image forming apparatus according to claim 78, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
82. The image forming apparatus according to claim 78, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
83. The image forming apparatus according to claim 77, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
84. The image forming apparatus according to claim 83, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
85. The image forming apparatus according to claim 77, wherein the charger charges the photoreceptor while contacting the surface of the photoreceptor.
86. The image forming apparatus according to claim 77, wherein the charger charges the photoreceptor while close to, but not touching, the surface of the photoreceptor.
87. The image forming apparatus according to claim 77, wherein the charger charges the photoreceptor while applying a DC voltage overlapped with an AC voltage to the surface of the photoreceptor.
88. The image forming apparatus according to claim 77, wherein the light irradiating device comprises a light source selected from the group consisting of laser diodes and light emitting diodes.
89. A process cartridge comprising a photoreceptor, wherein the process cartridge can be attached to and detached from an electrophotographic image forming apparatus, wherein the photoreceptor comprises an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, and wherein the photosensitive layer further comprises at least one ion selected from the group consisting of K, Na, NO3, HCOO, NO2, Cl, Br, and NH4.
90. The process cartridge according to claim 89, wherein 25 the organic pigment comprises a titanyl phthalocyanine.
91. The process cartridge according to claim 90, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
92. The process cartridge according to claim 90, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.2 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
93. The process cartridge according to claim 90, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
94. The process cartridge according to claim 90, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
95. The process cartridge according to claim 89, wherein the photosensitive layer comprises a K ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
96. The process cartridge according to claim 89, wherein the photosensitive layer comprises a Na ion in an amount not greater than 200 ppm relative to total amount of the organic pigment.
97. The process cartridge according to claim 89, wherein the photosensitive layer comprises a NO3 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
98. The process cartridge according to claim 89, wherein the photosensitive layer comprises a HCOO ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
99. The process cartridge according to claim 89, wherein the photosensitive layer comprises a NO2 ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
100. The process cartridge according to claim 89, wherein the photosensitive layer comprises a Cl ion in an amount not greater than 100 ppm relative to total amount of the organic pigment.
101. The process cartridge according to claim 89, wherein the photosensitive layer comprises a Br ion in an amount not greater than 50 ppm relative to total amount of the organic pigment.
102. The process cartridge according to claim 89, wherein the photosensitive layer comprises a NH4 ion in an amount of from 10 to 300 ppm relative to total amount of the organic pigment.
103. The process cartridge according to claim 89, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
104. The process cartridge according to claim 103, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.
105. A process cartridge comprising at least a photoreceptor, wherein the process cartridge can be attached to and detached from an electrophotographic image forming apparatus, wherein the photoreceptor comprises an electroconductive substrate and a photosensitive layer overlying the electroconductive substrate, wherein the photosensitive layer comprises a charge generation material comprising an organic pigment, wherein the photosensitive layer further comprises one or more water-soluble inorganic salts, and wherein the one or more water-soluble inorganic salts are present in the photosensitive layer in an amount not greater than 1000 ppm relative to total amount of the organic pigment.
106. The process cartridge according to claim 105, wherein the organic pigment comprises a titanyl phthalocyanine.
107. The process cartridge according to claim 106, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.60.2, 24.00.2 and 27.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
108. The process cartridge according to claim 106, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 7.50.2, 25.30.20 and 28.60.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
109. The process cartridge according to claim 106, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.30.2, 13.10.2 and 26.20.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
110. The process cartridge according to claim 106, wherein the titanyl phthalocyanine has an X-ray diffraction spectrum in which main diffraction peaks are observed at Bragg (2 ) angles of 9.00.2, 14.20.2, 23.90.2 and 27.1 0.2 when a specific X-ray of Cu-K having wavelength of 1.514 irradiates the titanyl phthalocyanine.
111. The process cartridge according to claim 105, wherein the photosensitive layer further comprises a charge generation layer comprising the charge generation material and a charge transport layer.
112. The process cartridge according to claim 111, wherein the charge transport layer comprises a polycarbonate resin comprising a triarylamine group in at least one of a main chain or a side chain thereof.