Novel xerographic plate containing photoinjecting bis-benzimidazole pigments

• US 3,879,200 A
• Filed: 04/05/1973
• Issued: 04/22/1975
• Est. Priority Date: 12/01/1970
• Status: Expired due to Term

• Current Assignee: James J. Jakubowski, Paul J. Regensburger
• Original Assignee: James J. Jakubowski, Paul J. Regensburger
• Inventors: Regensburger, Paul J., Jakubowski, James J.
• Primary Examiner(s): Torchin, Norman G.
• Assistant Examiner(s): Miller, John R.
• Application Number:
  US05/348,398
• Time in Patent Office: 747 Days
• Field of Search: 96/1.5,1.5C 117/201,215,218
• US Class Current: 430/58.6
• CPC Class Codes: G03G 5/047 characterised by the charge-generation layers or charge transport layers G03G5/0433 and G03G5/0436 take precedence
• CPC Class Codes: G03G 5/0659 containing more than seven relevant rings

Abstract

An electrophotographic plate having a photoreceptor comprising a photoinjecting pigment selected from the class of bisbenzimidazole pigments and an active transport material which is substantially transparent in the wavelength region of xerographic use and capable of supporting charge carrier injection from the pigment. The photoinjecting bis-benzimidazole pigments have the property of being efficient both in photogeneration of charge carriers and subsequent injection of the charge carriers into hole and electron transport active transport materials. The photoinjecting pigment and active transport material system may be used in a binder or layer type photoreceptor. The structure may be imaged in the conventional xerographic mode which usually includes charging, exposure to light, and development.

Claims

1. An electrophotographic plate having a photoreceptor member of from about 2 to 100 microns comprising a photoconductive material and an active transport material both of which are compatible so as to support efficient photogenerated charge injection from the photoconductive material, said photoconductive material being a photoinjecting pigment being selected from the class of bis-benzimidazole pigments in an amount between about 0.1 and 5 percent by volume of the active transport layer and said active transport material being a charge transport medium which is substantially nonabsorbing in the wavelength region of from about 4,000 to 6,500 Angstrom Units.

2. the electrophotographic plate of claim 1 in which the photoreceptor member comprises a bis-benzimidazole pigment dispersed in an active binder transport material.

3. The electrophotographic plate of claim 1 in which the photoreceptor member is a layered configuration comprising a bis-benzimidazole pigment single layer in contact with an active transport material overlayer, and wherein said active transport layer has a thickness of from about 5 to 100 microns, said photoconductor layer has a thickness of from 0.05 to 20 microns and the ratio of the thickness of the active transport layer to the photoconductor layer is from about 2:

1 to 200;

1.

4. An electrophotographic plate having a photoreceptor member of from about 2 to 100 microns comprising a photoconductive material and an active transport material both of which are compatible so as to support efficient photogenerated charge injection, said photoconductive material being a photoinjecting pigment being selected from the class of bis-benzimidazole pigments prepared by the reaction of 1,4,5,8-naphthalene tetracarboxylic acid with arylene and heterocyclic diamines in an amount between about 0.1 and 5 percent by volume of the active transport layer and said active transport material being a charge transport medium which is substantially non-absorbing in the wavelength region of from about 4,000 to 6,500 Angstroms.

5. The electrophotographic plate of claim 4 in which the bis-benzimidazole is the trans isomeric reaction product of 1,4,5,8-naphthalene tetracarbonxylic acid with 0-phenylene diamine.

6. The electrophotographic plate of claim 4 in which the bis-benzimidazole is the cis isomeric reaction product of 1,4,5,8-naphthalene tetracarboxylic acid with 0-phenylene diamine.

7. The electrophotographic plate of claim 4 in which the photoreceptor member comprises the bis-benzimidazole pigment dispersed in an active transport binder material.

8. The electrophotographic plate of claim 4 in which the photoreceptor member is a layered configuration comprising a bis-benzimidazole pigment single layer and an active transport overlayer in contact with said pigment layer, wherein the bis-benzimidazole pigment layer has a thickness of from about 0.05 to 20 microns and the active transport overlayer has a thickness of from about 5 to 100 microns, and wherein the ratio of the active transport material layer to the photoconductive layer is from about 2:

1 to 200;

1.

9. The elctrophotographic plate of claim 4 in which the active transport material is selected from the group of hole transport materials consisting of carbaZole, N-ethyl carbazole, N-phenylcarbazole, tetraphenylpyrene, 1-methylpyrene, perylene, chrysene, fluorene, fluorenone, anthracene, tetracene, tetraphene, 1-phenyl-naphthalene, azapyrene, 1-ethylpyrene, acetyl pyrene, 2,3-benzochrysene, 3,4-benzopyrene, 1,4-bromopyrene and phenyl indole, polyvinyl carbazole, polyvinyl pyrene, polyvinyl tetracene, polyvinyl perylene, and polyvinyl tetraphene.

10. The electrophotographic plate of claim 4 in which the active transport material is selected from the group of electron transport substances consisting of 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitrofluorenone, dinitroanthracene, dinitroacridene, tetracyanopyrene, dinitroanthraquinone, and polymeric materials containing said electron transport substance.

11. A method of imaging which comprises:

a. providing an electrophotographic plate having a photoreceptor member of from about 2 to 100 microns comprising a photoconductive material and an active transport material, said photoconductive material being a photoinjecting pigment being selected from the class of bis-benzimidazole pigments in an amount between about 0.1 and 5 percent by volume of the active transport layer, and said active transport material being a charge transport medium which is substantially nonabsorbing in the wavelength region of from about 4,000 to 6,500 Angstroms, b. uniformly charging said plate, and c. exposing said plate to a source of radiation in the wavelength region of from about 4,000 to 6,500 Angstroms whereby an electrostatic image is formed on the surface of said plate.

12. The method of claim 9 which further includes developing said latent image to make it visible.

13. The method of claim 9 in which the substrate is substantially transparent and exposure is carried out through said substrate.

14. The plate of claim 1 wherein the transport material is polyvinyl carbazole.

15. The plate of claim 3 wherein the transport material is polyvinyl carbazole.

16. The method of claim 11 wherein the transport material is polyvinyl carbazole.

17. The plate of claim 1 wherein the transport material is polyvinyl carbazole and the pigment is the cis form of bis-benzimidazodiaza pyrenedione.

18. The plate of claim 1 wherein the transport material is polyvinyl carbazole and the pigment is the trans form of bis-benzimidazodiaza pyrenedione.

19. The plate of claim 3 wherein the transport material is polyvinyl carbazole and the pigment is the cis form of bis-benzimidazodiaza pyrenedione.

20. The plate of claim 3 wherein the transport material is polyvinyl carbazole and the pigment is the trans form of bis-benzimidazodiaza pyrenedione.

21. The method of claim 11 wherein the transport material is polyvinyl carbazole and the pigment is the cis form of bis-benzimidazodiaza pyrenedione.