Electrophotographic photoreceptor

In the invention, there is provided an electrophotographic photoreceptor comprising a conductive substrate and a photosensitive layer formed thereon, said photosensitive layer containing an arylamine hydrazone compound represented by the following formula �I!. ##STR1##

What is claimed is:

1. An electrophotographic photoreceptor comprising a conductive substrate and a photosensitive layer formed thereon, the said photosensitive layer containing an arylamine hydrazone compound represented by the following formula �I!: ##STR30## wherein n is an integer of 2 or more; R.sup.1, R.sup.2 and R.sup.3 represent independently a hydrogen atom, an alkyl group which may have one or more substituent groups, an aryl group which may have one or more substituent groups, or a heterocyclic group which may have one or more substituent groups, and R.sup.1 's and R.sup.2 's in each repeating unit may be different from each other;

P has formula �II!: ##STR31## wherein Ar.sup.1 and Ar.sup.2 represent independently an alkyl group which may have one or more substituent groups, with the exclusion of benzyl or substituted benzyl an aryl group which may have one or more substituent groups, or a heterocyclic group which may have one ore more substituent groups, and Ar.sup.1 and Ar.sup.2 may be identical or different; Ar.sup.3 represents an arylene group which may have one or more substituent groups or a heterocyclic group which may have one or more substituent groups; dotted line 1, dotted line 2 and dotted line 3 indicate that Ar.sup.1 and Ar.sup.2, Ar.sup.1 and Ar.sup.3, and Ar.sup.2 and Ar.sup.3 may be coupled directly or via a linking group, respectively;

Q has formula �III!: ##STR32## wherein R.sup.4 and R.sup.5 represent independently an aryl group which may have one or more substituent groups, a heterocyclic group which may have one or more substituent groups, an alkyl group which may have one or more substituent groups, or an aralkyl group which may have one or more substituent groups,

provided that a compound where P in formula �I! having formula �IV! is excluded: ##STR33## wherein A, B and C benzene rings may independently have one or more substituent groups which may be identical or different; and D has one of formula �V!, �VI! or �VII!: ##STR34## wherein, in the formula �V!, Z represents an alkylene group which may have one or more substituent groups, and Ar.sup.4 represents an aryl group which may have one or more substituent groups or a heterocyclic group which may have one or more substituent groups; in the formula �VI!, R.sup.6 represents an alkyl group which may have one or more substituent groups, an aryl group which may have one or more substituent groups, a heterocyclic group which may have one or more substituent groups or an aralkyl group which may have one or more substituent groups; and in the formula �VII!, R.sup.7, R.sup.8, R.sup.9, R.sup.10 and R.sup.11 represent independently a hydrogen atom, an alkyl group which may have one or more substituent groups, an aryl group which may have one or more substituent groups or a heterocyclic group which may have one or more substituent groups.

2. An electrophotographic photoreceptor according to claim 1, wherein P in the formula �I! is a group having formula �VIII!: ##STR35## wherein A, B and C benzene rings may independently have one or more substituent groups which may be identical or different.

3. An electrophotographic photoreceptor according to claim 2, wherein A, B and C benzene rings in the formula �VIII! may independently be substituted by a methyl group or an ethyl group.

4. An electrophotographic photoreceptor according to claim 1, wherein R.sup.4 and R.sup.5 in the group represented by Q in the formula �I! are each an aryl group which may have one or more substituent groups.

5. An electrophotographic photoreceptor according to claim 1, wherein n in the formula �I! is an integer of 2 to 6.

6. An electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains a carrier transport material and a carrier generation material, said carrier transport material being an arylamine hydrazone compound represented by the formula �I!.

7. An electrophotographic photoreceptor according to claim 6, wherein the photosensitive layer comprises of a carrier generation layer containing a carrier generation material and a carrier transport layer containing a carrier transport material, said carrier transport material being an arylaminehydrazone compound represented by the formula �I!.

8. An electrophotographic photoreceptor according to claim 7, wherein the carrier transport layer contains a binder polymer.

9. An electrophotographic photoreceptor according to claim 6, wherein the carrier generation material is an azo pigment or a metal-containing phthalocyanine.

10. An electrophotographic photoreceptor according to claim 9, wherein the carrier generation material is an azo pigment having a coupler of the following structure �IX!: ##STR36##