Charge-transporting compound, electrophotographic photoreceptor, image-forming apparatus, and process cartridge

1. An electrophotographic photoreceptor comprising:

a conductive support;

a photosensitive layer comprising a charge generating layer and a charge transporting layer; and

a functional layer over said photosensitive layer that serves as a protective layer, the functional layer comprises a curable resin and at least one of: a first compound represented by formula (I); and a second compound derived from the first compound:

wherein F represents a hole-transporting, n-valent organic group;

R independently represents —CH 2 —R 4 or —(CH 2 ) r —O—R 5 , where

R 4 represents a C 1 -C 17 organic group,

R 5 represents a C 1 -C 6 hydrocarbon group, and

r represents an integer from 1-12;

T represents an alkylene group;

m indicates 1; and

n indicates an integer of from 1 to 4,

wherein the functional layer has a cross-linked structure formed by a crosslinking reaction between the curable resin and at least one of the first compound represented by formula (I) and the second compound derived from the first compound.

2. The electrophotographic photoreceptor as claimed in claim 1 , wherein the first compound is represented by formula (II):

wherein Ar 1 to Ar 4 may be the same or different, each representing a substituted or unsubstituted aryl group;

Ar 5 represents a substituted or unsubstituted aryl or arylene group;

each c independently indicates 0 or 1;

k indicates 0 or 1;

D represents a monovalent organic group represented by formula (III); and

the sum of c is from 1 to 4:

wherein R independently represents —CH 2 —R 4 or —(CH 2 ) r —O—R 5 , where

R 4 represents a C 1 -C 17 organic group,

R 5 represents a C 1 -C 6 hydrocarbon group, and

r represents an integer from 1-12;

T represents an alkylene group; and

m indicates 1.

3. The electrophotographic photoreceptor as claimed in claim 1 , wherein the functional layer is on the side of the photosensitive layer remotest from the conductive support.

4. The electrophotographic photoreceptor as claimed in claim 1 , wherein the curable resin is at least one selected from a group consisting of phenolic resin, melamine resin, benzoguanamine resin, siloxane resin and urethane resin.

5. The electrophotographic photoreceptor as claimed in claim 1 , wherein the functional layer further comprises a material comprising a fluorine element or a silicon element.

6. The electrophotographic photoreceptor as claimed in claim 1 , wherein the functional layer further comprises at least one or more antioxidants.

7. The electrophotographic photoreceptor as claimed in claim 1 , wherein the functional layer further comprises at least one or more types of fine particles.

8. The electrophotographic photoreceptor as claimed in claim 1 , wherein the functional layer has an oxygen transmission coefficient at 25° C. of 4×10 12 fm/s·Pa or less.

9. The electrophotographic photoreceptor as claimed in claim 1 , wherein a charge-transporting material in the photosensitive layer is different from the first compound represented by formula (I) in the functional layer.

10. The electrophotographic photoreceptor as claimed in claim 1 , wherein a charge-transporting material in the photosensitive layer is selected from the group consisting of compounds (IV-1), (IV-2), and (IV-3):

wherein:

R 14 represents a hydrogen atom or a methyl group;

n indicates 1 or 2;

Ar 6 and Ar 7 each independently represent a substituted or unsubstituted aryl group, —C 6 H 4 —C(R 18 )═C(R 19 )(R 20 ) or —C 6 H 4 —CH═CH—CH═C(Ar) 2 , and the substituent for these is a halogen atom, an alkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, or a substituted amino group substituted with an alkyl group having from 1 to 3 carbon atoms;

R 18 , R 19 and R 20 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; and

Ar represents a substituted or unsubstituted aryl group;

wherein:

R 15 and R 15′ each independently represent a hydrogen atom, a halogen atom, an alkyl group having from 1 to 5 carbon atoms, or an alkoxy group having from 1 to 5 carbon atoms;

R 16 , R 16′ , R 17 and R 17′ each independently represent a halogen atom, an alkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, an amino group substituted with an alkyl group having 1 or 2 carbon atoms, a substituted or unsubstituted aryl group, —C 6 H 4 —C(R 18 )═C(R 19 )R 20 ) or —C 6 H 4 —CH═CH—CH═C(Ar) 2 ;

R 18 , R 19 and R 20 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group;

Ar represents a substituted or unsubstituted aryl group;

and m and n each independently indicate an integer of from 0 to 2;

wherein:

R 21 represents a hydrogen atom, an alkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, a substituted or unsubstituted aryl group, or —CH═CH—CH═C(Ar) 2 ;

Ar represents a substituted or unsubstituted aryl group;

R 22 and R 23 each independently represent a hydrogen atom, a halogen atom, an alkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, an amino group substituted with an alkyl group having 1 or 2 carbon atoms, or a substituted or unsubstituted aryl group.

11. The electrophotographic photoreceptor as claimed in claim 1 , wherein the curable resin is a silicone resin.

12. The electrophotographic photoreceptor according to claim 1 , wherein T represents a methylene, ethylene, or propylene group.

13. An image-forming apparatus comprising:

an electrophotographic photoreceptor comprising: a conductive support; a photosensitive layer comprising a charge generating layer and a charge transporting layer; and a functional layer over said photosensitive layer that serves as a protective layer, the functional layer comprises a curable resin and at least one of: a first compound represented by formula (I); and a second compound derived from the first compound;

a charging device that charges the electrophotographic photoreceptor;

an exposing device that exposes the charged electrophotographic photoreceptor to light to form an electrostatic latent image thereon;

a developing device that develops the electrostatic latent image to form a toner image; and

a transfer device that transfers the toner image onto a transfer medium,

wherein F represents a hole-transporting, n-valent organic group;

R independently represents —CH 2 —R 4 or —(CH 2 ) r —O—R 5 , where

R 4 represents a C 1 -C 17 organic group,

R 5 represents a C 1 -C 6 hydrocarbon group, and

r represents an integer from 1-12;

T represents an alkylene group;

m indicates 1; and

n indicates an integer of from 1 to 4,

wherein the functional layer has a cross-linked structure formed by a crosslinking reaction between the curable resin and at least one of the first compound represented by formula (I) and the second compound derived from the first compound.

14. The image-forming apparatus as claimed in claim 13 , comprising:

a photoreceptor unit comprising at least the electrophotographic photoreceptor; and

a developing unit comprising at least the developing device,

wherein the photoreceptor unit and the developing unit are separated from each other.

15. The image-forming apparatus as claimed in claim 13 , further comprising a blade cleaner as a cleaning device that removes a remaining toner on the electrophotographic photoreceptor after a transfer step.

16. The image-forming apparatus as claimed in claim 15 , wherein the electrophotographic photoreceptor is fixed to the image-forming apparatus and the blade cleaner is detachably fixed to the image-forming apparatus.

17. The image-forming apparatus as claimed in claim 13 , wherein the electrophotographic photoreceptor is fixed to the image-forming apparatus and the charging device is detachably fixed to the image-forming apparatus.

18. The image-forming apparatus as claimed in claim 13 , further comprising a fibrous member fittable to the electrophotographic photoreceptor.

19. The image-forming apparatus as claimed in claim 13 , comprising a plurality of image-forming units each of which comprises: the electrophotographic photoreceptor; the charging device; the exposing device; and the developing device,

wherein the transfer device comprises an intermediate transfer medium that primarily transfers the toner image formed on the electrophotographic photoreceptor and secondarily transfers the primarily-transferred image onto the transfer medium, and

wherein said plurality of image-forming units are located on the intermediate transfer medium.

20. The image-forming apparatus as claimed in claim 13 , wherein the exposing device is a multi-beam surface-emitting laser.

21. The image-forming apparatus as claimed in claim 13 , further comprising:

a lubricant supplying device the supplies a lubricant to the electrophotographic photoreceptor.

22. A process cartridge comprising:

an electrophotographic photoreceptor comprising: a conductive support; a photosensitive layer comprising a charge generating layer and a charge transporting layer; and a functional layer over said photosensitive layer that serves as a protective layer, the functional layer comprises a curable resin and at least one of: a first compound represented by formula (I); and a second compound derived from the first compound; and

at least one selected from: a charging device that charges the electrophotographic photoreceptor; a developing device that develops an electrostatic latent image formed through exposing the charged electrophotographic photoreceptor to form a toner image; and a cleaning device that removes a toner that remains on the electrophotographic photoreceptor after transfer,

wherein F represents a hole-transporting, n-valent organic group;

R independently represents —CH 2 —R 4 or —(CH 2 ) r —O—R 5 , where

R 4 represents a C 1 -C 17 organic group,

R 5 represents a C 1 -C 6 hydrocarbon group, and

r represents an integer from 1-12;

T represents an alkylene group;

m indicates 1; and

n indicates an integer of from 1 to 4,

wherein the functional layer has a cross-linked structure formed by a crosslinking reaction between the curable resin and at least one of the first compound represented by formula (I) and the second compound derived from the first compound.

23. An electrophotographic photoreceptor comprising:

a conductive support;

a photosensitive layer comprising a charge generating layer and a charge transporting layer; and

a functional layer over said photosensitive layer that serves as a protective layer, wherein

the functional layer comprises a curable resin and at least one of: a first compound represented by formula (I), and a second compound derived from the first compound:

wherein F represents a hole-transporting, n-valent organic group;

R independently represents —CH 2 —R 4 or —(CH 2 ) r —O—R 5 , where

R 4 represents a C 1 -C 17 organic group,

R 5 represents a C 1 -C 6 hydrocarbon group, and

r represents an integer from 1-12;

T represents an alkylene group;

m indicates 1; and

n indicates an integer of from 1 to 4; and

the functional layer has a cross-linked structure comprising the at least one of the first compound represented by the formula (I) and the second compound derived from the first compound, and the curable resin bonded to the at least one of a first compound represented by the formula (I) and the second compound derived from the first compound.