Patent ID: 6835512
Filing Date: 2004-12-28
Classification: G03G

Abstract:
An electrophotographic photosensitive member comprising, in this order, a photosensitive layer and a protective layer on a conductive substrate, the photosensitive layer comprising a binder resin, a charge-generating material and a first charge transport material and the protective layer comprising a cured resin and a second charge transport material, the photosensitive layer and the protective layer being in contact with each other, wherein the electrophotographic photosensitive member has Vsl(0.2) and Vsl(0.5) which are surface potentials of the electrophotographic photosensitive member, respectively, 0.2 second and 0.5 second after irradiation of the electrophotographic photosensitive member which has been charged to âˆ’700V with white light in a quantity of 10 lux.sec under a 23Â° C. and 75% RH environment and wherein Vsl(0.2) and Vsl(0.5) satisfy the following formulas (1) and (2),20(V)&lE;|Vsl(0.2)|&lE;80(V)â€ƒâ€ƒ(1) 10(V)&lE;|Vsl(0.2)âˆ’Vsl(0.5)|&lE;30(V)â€ƒâ€ƒ(2) and wherein the second charge transporting material is at least one compound represented by any one of the following formulas (2) to (7): wherein R21, R22 and R23 are each independently a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; benzene rings &agr;, &bgr; and &ggr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; and a, b, d, m and n are each independently 0 or 1, wherein R31, R32 and R33 are each independently a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; benzene rings &dgr; and &egr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; e, f and g are each independently 0 or 1; p, q and r are each independently 0 or 1 provided that all of them are not 0 at the same time; and Z31 and Z32 are each independently a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group, or are combined together to form a ring, wherein R41, R42, R43 and R44 are each independently a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; benzene rings &zgr;, &eegr;, &thgr; and &igr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; h, i, j, k, s, t and u are each independently 0 or 1; and Z41 and Z42 are each independently a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group, or are combined together to form a ring, wherein R51 is a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; R52 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted phenyl group; Ar51 and Ar52 are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; Ar53 is a divalent, substituted or unsubstituted aromatic hydrocarbon ring group or a divalent, substituted or unsubstituted aromatic heterocyclic group; v and w are each independently 0 or 1 provided that when v is 0, w is 0; and benzene rings &kgr; and &lgr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group, wherein R61 is a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; Ar61 and Ar62 are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; x is 0 or 1; benzene rings &mgr; and &ngr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group, or may be combined together to form a ring through a substituent; wherein R71 and R72 are each independently a divalent, branched or unbranched hydrocarbon group having 1 to 8 carbon atoms; Ar71 is a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group; y and z are each independently 0 or 1; benzene rings &xgr;, &pgr;, &rgr; and &sgr; may each independently have a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aromatic hydrocarbon ring group or a substituted or unsubstituted aromatic heterocyclic group, or the benzene rings &xgr; and &pgr; and the benzene rings &rgr; and &sgr; may be each independently combined together to form a ring through a substituent.