Di-hydrazone based charge transport compounds

1. An organophotoreceptor comprising:

(a) a charge transport compound having the formula

where R 1 and R 2 are, independently, an (N,N-substituted)arylamine group;

R 3 and R 4 are, independently, an alkylsulfonylphenyl group; and

X is a linking group having the formula —(CH 2 ) m —, branched or linear, where m is an integer between 0 and 20, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, urethane, urea, an ester group, a —NR 5 group, a CHR 6 group, or a CR 7 R 8 group where R 5 , R 6 , R 7 , and R 8 are, independently, H, an alkyl group, or aryl group;

(b) a charge generating compound; and

(c) an electrically conductive substrate over which said charge transport compound and said charge generating compound are located.

2. An organophotoreceptor according to claim 1 wherein said organophotoreceptor is in the form of a flexible belt.

3. An organophotoreceptor according to claim 1 wherein said organophotoreceptor is in the form of a drum.

4. An organophotoreceptor according to claim 1 comprising:

(a) a charge transport layer comprising said charge transport compound and a polymeric binder; and

(b) a charge generating layer comprising said charge generating compound and a polymeric binder.

5. An organophotoreceptor according to claim 1 wherein said charge transport compound is selected from the group consisting of:

where R is CH 3 (CH 2 ) m , branched or linear, where n is an integer between 0 and 30, inclusive; and

6. An electrophotographic imaging apparatus comprising:

(a) a plurality of support rollers; and

(b) an organophotoreceptor operably connected to said support rollers with motion of the support rollers resulting in motion of said organophotoreceptor, said organophotoreceptor comprising:

(i) a charge transport compound having the formula

where R 1 and R 2 are, independently, an (N,N-disubstituted)arylamine;

R 3 and R 4 are, independently, an alkylsulfonylphenyl group; and

X is a linking group having the formula —CH 2 ) m —, branched or linear, where m is an integer between 0 and 20, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, urethane, urea, an ester group, a —NR 5 group, a CHR 6 group, or a CR 7 R 8 group where R 5 , R 6 , R 7 , and R 8 are, independently, H, an alkyl group, or aryl group;

(ii) a charge generating compound; and

(iii) an electrically conductive substrate over which said charge transport compound and said charge generating compound are located.

7. The electrophotographic imaging apparatus of claim 6 wherein R 1 and R 2 are, independently, a julolidine group, a triphenyl amine group, or an N-substituted carbazole group.

8. The electrophotographic imaging apparatus of claim 6 further comprising a liquid toner dispenser.

9. The electrophotographic imaging apparatus of claim 6 wherein said organophotoreceptor comprises a drum that supports the electrically conductive substrate.

10. The electrophotographic imaging apparatus of claim 6 wherein said organophotoreceptor comprises a belt that supports the electrically conductive substrate.

11. An electrophotographic imaging process comprising:

(a) applying an electrical charge to a surface of an organophotoreceptor comprising:

(i) a charge transport compound having the formula

where R 1 and R 2 are, independently, an (N,N-disubstituted)arylamine group;

R 3 and R 4 are, independently, an alkylsulfonylphenyl group; and

X is a linking group having the formula —(CH 2 ) m —, branched or linear, where m is an integer between 0 and 20, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, urethane, urea, an ester group, a —NR 5 group, a CHR 6 group, or a CR 7 R 8 group where R 5 , R 6 , R 7 , and R 8 are, independently, H, an alkyl group, or aryl group;

(ii) a charge generating compound; and

(iii) an electrically conductive substrate over which said charge transport compound and said charge generating compound are located;

(b) imagewise exposing said surface of said organophotoreceptor to radiation to dissipate charge in selected areas and thereby form a pattern of charged and uncharged areas on said surface;

(c) contacting said surface with a liquid toner comprising a dispersion of colorant particles in an organic liquid to create a toned image; and

(d) transferring said toned image to a substrate.

12. The electrophotometric imaging process of claim 11 wherein R 1 and R 2 are, independently, a julolidine group, a triphenyl amine group, or a carbazole group.

13. A charge transport compound having the formula

where R 1 and R 2 are, independently, an (N,N-disubstituted)arylamine group;

R 3 and R 4 are, independently, an alkylsulfonylphenyl group; and

X is a linking group having the formula —CH 2 ) m —, branched or linear, where m is an integer between 0 and 20, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, urethane, urea, an ester group, a —NR 5 group, a CHR 6 group, or a CR 7 R 8 group where R 5 , R 6 , R 7 , and R 8 are, independently, H, an alkyl group, or aryl group.

14. The charge transport compound of claim 13 wherein R 1 and R 2 are, independently, a julolidine group, a triphenyl amine group, or a N-substituted carbazole group.

15. The charge transport compound of claim 13 wherein R 1 and R 2 each comprise a julolidine group.

16. The charge transport compound of claim 13 wherein R 1 and R 2 each comprise a triphenyl amine group.

17. The charge transport compound of claim 13 wherein R 1 and R 2 each comprise an N-substituted carbazole group.

18. The charge transport compound of claim 13 wherein R 1 and R 2 are different.