Photoreceptors

• US 20060236893A1
• Filed: 04/22/2005
• Published: 10/26/2006
• Est. Priority Date: 04/22/2005
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Wu, Jin, Lin, Liang-Bih, Chambers, John S., Lopez, Francisco Jose
• Granted Patent: US 7,169,920 B2
• Time in Patent Office: Days
• US Class Current: 106/410
• CPC Class Codes: C09B 67/0035 Mixtures of phthalocyanines
• CPC Class Codes: G03G 5/0696 Phthalocyanines

Abstract

Methods for preparing phthalocyanine co-crystals are provided. The phthalocyanine co-crystals include titanyl phthalocyanines and metal free phthalocyanines.

Claims

1. A method which comprises:

contacting a metal phthalocyanine and a metal free phthalocyanine with at least one solvent; and

recovering said phthalocyanine product as a cocrystal.

2. The method of claim 1 wherein the metal phthalocyanine is selected from the group consisting of titanyl phthalocyanine, hydroxygallium phthalocyanine, cholorogallium phthalocyanine and zirconyl phthalocyanine.

3. The method of claim 1 wherein the metal phthalocyanine comprises titanyl phthalocyanine.

4. The method of claim 1 wherein the metal phthalocyanine comprises hydroxygallium phthalocyanine.

5. The method of claim 1 wherein the solvent is selected from the group consisting of protonic acids, aromatic solvents, ethers, pyrrolidinones, alkyl halides, alkylene halides, and mixtures thereof.

6. The method of claim 1 wherein the solvent is selected from the group consisting of trifluoroacetic acid, toluene, tetrahydrofuran, N-methylpyrrolidinone, chloroform, methylene chloride, and mixtures thereof.

7. The method of claim 1 wherein the solvent comprises a mixture of trifluoroacetic acid and methylene chloride, optionally at a ratio of from about 1:

10 parts by volume to about 10;

1 parts by volume.

8. The method of claim 1, further comprising adding the solution obtained subsequent to the mixing to a nonsolvent selected from the group consisting of alcohols, water, alkylene halides, ketones and mixtures thereof, wherein the nonsolvent enables the precipitation of the phthalocyanine co-crystals.

9. The method of claim 8 wherein the nonsolvent comprises a mixture of methanol and methylene chloride.

10. The method of claim 1 wherein the phthalocyanine co-crystals are separated from the solution by filtration.

11. The method of claim 1, further comprising converting the phthalocyanine co-crystals to a photosensitive pigment by adding the phthalocyanine co-crystals to an aromatic solvent selected from the group consisting of aromatic hydrocarbons, aromatic nitro compounds, aromatic halogen compounds, and phenols.

12. The method of claim 11 wherein the aromatic solvent further comprises an alcohol solvent.

13. The method of claim 1 wherein the phthalocyanine co-crystal comprises a metal phthalocyanine and metal free phthalocyanine at a weight ratio ranging from about 99:

1 to about 10;

90.

14. A phthalocyanine co-crystal produced by the method of claim 1.

15. A method for the preparation of phthalocyanine co-crystals which comprises:

contacting a titanyl phthalocyanine and a metal free phthalocyanine to a solvent comprising trifluoroacetic acid and methylene chloride;

contacting the resulting solution with a nonsolvent selected from the group consisting of selected from the group consisting of alcohols, water, alkylene halides, ketones and combinations thereof to precipitate the phthalocyanine co-crystals;

contacting the precipitated co-crystal phthalocyanine with an aromatic solvent; and

recovering the phthalocyanine co-crystals.

16. The method of claim 15 wherein the ratio of trifluoroacetic acid to methylene chloride ranges from about 1:

10 parts by volume to about 10;

1 parts by volume.

17. The method of claim 15 wherein the nonsolvent comprises a mixture of methanol and methylene chloride at a ratio ranging from about 95:

5 parts by volume to about 5;

95 parts by volume.

18. The method of claim 15 wherein the phthalocyanine co-crystal precipitated product is separated from the nonsolvent by filtration.

19. The method of claim 15, wherein the aromatic solvent is selected from the group consisting of aromatic hydrocarbons, aromatic nitro compounds, aromatic halogen compounds, and phenols.

20. The method of claim 15 wherein the aromatic solvent further comprises an alcohol solvent, optionally at a ratio of aromatic solvent to alcohol solvent ranging from about 99:

1 to about 1;

99.

21. The method of claim 15 wherein the phthalocyanine co-crystal comprises a titanyl phthalocyanine and a metal free phthalocyanine at a weight ratio ranging from about 99:

1 to about 10;

90.

22. A phthalocyanine co-crystal produced by the method of claim 15.

23. A phthalocyanine co-crystal comprising a titanyl phthalocyanine and a metal free phthalocyanine wherein the weight ratio of the titanyl phthalocyanine to the metal free phthalocyanine is from about 99:

1 to about 10;

90.

24. The phthalocyanine co-crystal of claim 23 wherein the weight ratio of the titanyl phthalocyanine to the metal free phthalocyanine is from about 95:

5 to about 50;

50.