ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

• US 20090324282A1
• Filed: 09/08/2009
• Published: 12/31/2009
• Est. Priority Date: 09/10/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tanaka, Takakazu, Kaku, Kenichi, Ogaki, Harunobu, Yoshida, Akira
• Granted Patent: US 7,927,774 B2
• Time in Patent Office: Days
• US Class Current: 399/111
• CPC Class Codes: G03G 5/056 Polyesters
• CPC Class Codes: G03G 5/14752 Polyesters

Abstract

An object of the present invention is to provide an electrophotographic photosensitive member having high durability and hardly causing sensitivity decrease even if short wavelength light, particularly light having a wavelength of 380 to 450 nm is used as exposure light, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member. The present invention includes an electrophotographic photosensitive member comprising a support and a photosensitive layer which is provided on the support and contains a charge generation material and a charge transport material, characterized in that the surface layer of the electrophotographic photosensitive member contains an aliphatic dicarboxylic acid polyester resin with a weight average molecular weight of 80,000 or more having a specific repeating structural unit, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

Claims

1. An electrophotographic photosensitive member comprising a support and a photosensitive layer which is provided on the support and contains a charge generation material and a charge transport material, characterized in that the surface layer of the electrophotographic photosensitive member contains an aliphatic dicarboxylic acid polyester resin with a weight average molecular weight of 80,000 or more having a repeating structural unit represented by the following formula (1):

wherein R¹¹ to R¹⁸ are each independently a hydrogen atom, an alkyl group, an alkoxy group or an aryl group, X¹¹ is a substituted or unsubstituted alkylene group having 3 to 10 carbon atoms in the main chain, a substituted or unsubstituted cycloalkylene group having 5 to 10 carbon atoms in the ring or a substituted or unsubstituted bicycloalkylene group having 5 to 10 carbon atoms in the ring, and Y¹¹ is a single bond, a Group 16 element or a divalent group having a structure represented by the following formula (2);

wherein R²¹ and R²² are each independently a hydrogen atom, an alkyl group, a fluoroalkyl group, an alkoxy group or an aryl group, or R²¹ and R²² are bonded together to form a cycloalkylidene group or a fluorenylidene group.

2. The electrophotographic photosensitive member according to claim 1, wherein at least one of R¹¹ to R¹⁸ is an alkyl group, an alkoxy group or an aryl group, and Y¹¹ is a single bond.

3. The electrophotographic photosensitive member according to claim 1, wherein Y¹¹ is an oxygen atom or a sulfur atom.

4. The electrophotographic photosensitive member according to claim 1, wherein at least one of R¹¹ to R¹⁸ is an alkyl group, an alkoxy group or an aryl group, Y¹¹ is a divalent group having a structure represented by the formula (2) and R²¹ and R²² are each independently an alkyl group or a fluoroalkyl group.

5. The electrophotographic photosensitive member according to claim 1, wherein at least one of R¹¹ to R¹⁸ is an alkyl group, an alkoxy group or an aryl group, Y¹¹ is a divalent group having a structure represented by the formula (2) and R²¹ and R²² are bonded together to form a cyclohexylidene group.

6. The electrophotographic photosensitive member according to claim 1 wherein X¹¹ is a substituted or unsubstituted butylene group, a substituted or unsubstituted pentylene group, a substituted or unsubstituted hexylene group, a substituted or unsubstituted heptylene group, a substituted or unsubstituted octylene group or a substituted or unsubstituted cyclohexylene group.

7. The electrophotographic photosensitive member according to claim 1 wherein the photosensitive layer is a multi-layer type photosensitive layer comprising a charge generation layer containing the charge generation material and a charge transport layer containing the charge transport material, the charge transport layer being the surface layer of the electrophotographic photosensitive member.

8. A process cartridge comprising the electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of a charging means, a developing means, a transferring means and a cleaning means, which are integrally held, characterized in that the process cartridge is detachably attached to a body of an electrophotographic apparatus.

9. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging means, an exposure means, a developing means and a transferring means.

10. The electrophotographic apparatus according to claim 9, wherein the exposure means is for irradiating the electrophotographic photosensitive member with light having a wavelength of 380 to 450 nm as exposure light.

11. The electrophotographic apparatus according to claim 10, wherein the exposure means has a laser with an oscillation wavelength in the range of 380 to 450 nm.