ELECTROPHOTOGRAPHIC PHOTORECEPTOR, IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE THEREFOR USING THE ELECTROPHOTOGRAPHIC PHOTORECEPTOR

• US 20100172670A1
• Filed: 12/18/2009
• Published: 07/08/2010
• Est. Priority Date: 01/06/2009
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Kami, Hidetoshi, OHSHIMA, Kohichi, Fujiwara, Yukio, Egawa, Kazuhiro
• Granted Patent: US 8,420,284 B2
• Time in Patent Office: Days
• US Class Current: 399/111
• CPC Class Codes: G03G 15/751 relating to drum G03G15/757 takes precedence
• CPC Class Codes: G03G 2215/00957 Compositions
• CPC Class Codes: G03G 5/0525 Coating methods
• CPC Class Codes: G03G 5/0596 Macromolecular compounds characterised by their physical properties
• CPC Class Codes: G03G 5/072 comprising pending monoamine groups
• CPC Class Codes: G03G 5/0732 comprising pending alkenylarylamine
• CPC Class Codes: G03G 5/147 Cover layers
• 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

Abstract

An electrophotographic photoreceptor, including an electroconductive substrate; a photosensitive layer, located overlying the electroconductive substrate; and an outermost layer comprising a convexity, wherein each of the outermost layer and the convexity includes a crosslinked body including a structural unit having a same charge transportable structure, and wherein the number of convexity having a height not less than ½×RzJIS is from 30 to 300 in a measurement length of 12 mm, wherein RzJIS is an average of ten-point mean roughness specified in JIS B0601 of 2001 and measured at least 4 random positions in an area the outermost layer is formed on, and wherein the height of the convexity is a distance from the deepest valley to a top of the convexity in the measurement length of 12 mm.

Claims

1. An electrophotographic photoreceptor, comprising:

an electroconductive substrate;

a photosensitive layer, located overlying the electroconductive substrate; and

an outermost layer including a convexity, located overlying the photosensitive layer,

wherein each of the outermost layer and the convexity includes a crosslinked body including a structural unit having a same charge transportable structure, and wherein the number of convexity having a height not less than ½

×

RzJIS is from 30 to 300 in a measurement length of 12 mm, wherein RzJIS is an average of ten-point mean roughness specified in JIS 80601 of 2001 and measured at least 4 random positions in an area the outermost layer is formed on, and wherein the height of the convexity is a distance from the deepest valley to a top of the convexity in the measurement length of 12 mm.

2. The electrophotographic photoreceptor of claim 1, wherein the height of the convexity is from 0.05 to 6 μ

m on average.

3. The electrophotographic photoreceptor of claim 1, wherein the structural unit having a same charge transportable structure is a triarylamine structure.

4. The electrophotographic photoreceptor of claim 1, wherein the crosslinked body is formed by crosslinking a coating liquid compising compound having the following formula (1):

wherein each of d, e and f is 0 or 1;

each of g and h is 0 or an integer of from 1 to 3;

R₁₃ represents a hydrogen atom or a methyl group;

each of R₁₄ and R₁₅ represents an alkyl group having from 1 to 6 carbon atoms, wherein when g is 2 or 3, the groups R₁₄ may be the same as or different from each other, and when h is 2 or 3, the groups R₁₅ may be the same as or different from each other;

Z represents a methylene group, an ethylene group or one of the following groups;

and j is 0 or 1.

5. The electrophotographic photoreceptor of claim 1, wherein the convexity is formed by a spray coating method.

6. An image forming apparatus, comprising:

an electrophotographic photoreceptor;

a charging device configured to charge the electrophotographic photoreceptor;

an irradiating device configured to irradiate the electrophotographic photoreceptor to form an electrostatic latent image thereon;

a developing device configured to develop the electrostatic latent image with a toner to form a toner image on the electrophotographic photoreceptor; and

a transferring device configured to transfer the toner image onto a receiving material,

wherein the electrophotographic photoreceptor is the electrophotographic photoreceptor according to claim 1.

7. The image forming apparatus of claim 6, wherein the toner is a toner prepared by a polymerization method.

8. The image forming apparatus of claim 6, further comprising at least two tandem developing stations each comprising the electrophotographic photoreceptor, the charging device, the irradiating device, the developing device and the transferring device.

9. The image forming apparatus of claim 6, further comprising a process cartridge detachable from the image forming apparatus, comprising:

an electrophotographic photoreceptor;

a developing device; and

a cleaning device.

10. A process cartridge detachable from image forming apparatus, comprising:

an electrophotographic photoreceptor;

a developing device; and

a cleaning device,

wherein the electrophotographic photoreceptor is the electrophotographic photoreceptor according to claim 1.