Toner compositions comprising polyester resin and poly (3,4-ethylenedioxythiophene)

• US 6,730,450 B1
• Filed: 11/28/2000
• Issued: 05/04/2004
• Est. Priority Date: 11/28/2000
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Moffat, Karen A., Carlini, Rina, Hays, Dan A., McDougall, Maria N. V., LeStrange, Jack T.
• Primary Examiner(s): Dote, Janis L.
• Application Number:
  US09/724,064
• Time in Patent Office: 1,253 Days
• Field of Search: 430/108.5, 430/110.2, 430/137.14, 430/137.12, 430/137.19, 430/137.2, 430/109.4, 430/110, 430/137.11
• US Class Current: 430/108.5
• CPC Class Codes: G03G 9/0804 whereby the components are brought together in a liquid dispersing medium
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/08771 Polymers having sulfur in the main chain, with or without oxygen, nitrogen or carbon only

Abstract

Disclosed is a toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent image by contacting the imaging member with charged toner particles comprising a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process.

Claims

1. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein the toner particles comprise a core comprising the polyester resin and optional colorant and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the polyester resin is a sulfonated polyester, and wherein the sulfonated polyester resin acts as a dopant for the poly(3,4-ethylenedioxythiophene).

2. A toner according to claim 1 wherein the toner particles have an average particle diameter of no more than about 13 microns.

3. A toner according to claim 1 wherein the sulfonated resin is a salt of a poly(1,2-propylene-5-sulfoisophthalate), a poly(neopentylene-5-sulfoisophthalate), a poly(diethylene-5-sulfoisophthalate), a copoly(1,2-propylene-5-sulfoisophthalate)-copoly-(1,2-propylene-terephthalate phthalate), a copoly(1,2-propylene-diethylene-5-sulfoisophthalate)-copoly-(1,2-propylene-diethylene-terephthalate phthalate), a copoly(ethylene-neopentylene-5-sulfoisophthalate)-copoly-(ethylene-neopentylene-terephthalate-phthalate), a copoly(propoxylated bisphenol A)-copoly-(propoxylated bisphenol A-5-sulfoisophthalate), a copoly(ethylene-terephthalate)-copoly-(ethylene-5-sulfo-isophthalate), a copoly(propylene-terephthalate)-copoly-(propylene-5-sulfo-isophthalate), a copoly(diethylene-terephthalate)-copoly-(diethylene-5-sulfo-isophthalate), a copoly(propylene-diethylene-terephthalate)-copoly-(propylene-diethylene-5-sulfoisophthalate), a copoly(propylene-butylene-terephthalate)-copoly(propylene-butylene-5-sulfo-isophthalate), a copoly(propoxylated bisphenol-A-fumarate)-copoly(propoxylated bisphenol A-5-sulfo-isophthalate), a copoly(ethoxylated bisphenol-A-fumarate)-copoly-(ethoxylated bisphenol-A-5-sulfo-isophthalate), a copoly(ethoxylated bisphenol-A-maleate)-copoly(ethoxylated bisphenol-A-5-sulfo-isophthalate), a copoly(propylene-diethylene terephthalate)-copoly(propylene-5-sulfoisophthalate), a copoly(neopentyl-terephthalate)-copoly-(neopentyl-5-sulfoisophthalate), or a mixture thereof.

4. A toner according to claim 1 wherein the resin is present in the toner particles in an amount of at least about 75 percent by weight of the toner particles and wherein the resin is present in the toner particles in an amount of no more than about 99 percent by weight of the toner particles.

5. A toner according to claim 1 wherein the toner particles further comprise a pigment colorant.

6. A toner according to claim 1 wherein the toner particles contain a colorant, said colorant being present in an amount of at least about 1 percent by weight of the toner particles, and said colorant being present in an amount of no more than about 25 percent by weight of the toner particles.

7. A toner according to claim 1 wherein the emulsion aggregation process comprises (1) shearing a first ionic surfactant with a latex mixture comprising (a) a counterionic surfactant with a charge polarity of opposite sign to that of said first ionic surfactant, (b) a nonionic surfactant, and (c) the sulfonated polyester resin, thereby causing flocculation or heterocoagulation of formed particles of resin to form electrostatically bound aggregates;

and (2) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter.

8. A toner according to claim 1 wherein the emulsion aggregation process comprises (1) preparing a colorant dispersion in a solvent, which dispersion comprises a colorant and a first ionic surfactant;

(2) shearing the colorant dispersion with a latex mixture comprising (a) a counterionic surfactant with a charge polarity of opposite sign to that of said first ionic surfactant, (b) a nonionic surfactant, and (c) the sulfonated polyester resin, thereby causing flocculation or heterocoagulation of formed particles of colorant and resin to form electrostatically bound aggregates; and

(3) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter.

9. A toner according to claim 1 wherein the emulsion aggregation process comprises (1) shearing an ionic surfactant with a latex mixture comprising (a) a flocculating agent, (b) a nonionic surfactant, and (c) the sulfonated polyester resin, thereby causing flocculation or heterocoagulation of formed particles of colorant and resin to form electrostatically bound aggregates;

and (2) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter.

10. A toner according to claim 1 wherein the emulsion aggregation process comprises (1) preparing a colorant dispersion in a solvent, which dispersion comprises a colorant and an ionic surfactant;

(2) shearing the colorant dispersion with a latex mixture comprising (a) a flocculating agent, (b) a nonionic surfactant, and (c) the sulfonated polyester resin, thereby causing flocculation or heterocoagulation of formed particles of colorant and resin to form electrostatically bound aggregates; and

(3) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter.

11. A toner according to claim 1 wherein the emulsion aggregation process comprises (1) preparing a colloidal solution comprising the sulfonated polyester resin and the optional colorant, and (2) adding to the colloidal solution an aqueous solution containing a coalescence agent comprising an ionic metal salt to form toner particles.

12. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is formed from monomers of the formula

wherein each of R₁, R₂, R₃, and R₄, independently of the others, is a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, an alkylaryloxy group, or a heterocyclic group.

13. A toner according to claim 12 wherein R₁ and R₃ are hydrogen atoms and R₂ and R₄ are (a) R₂=H, R₄=H;

(b) R₂=(CH₂)_nCH3 wherein n=0-14, R₄=H;

(c) R₂=(CH₂)_nCH3 wherein n=0-14, R₄=(CH₂)_nCH3 wherein n=0-14;

(d) R₂=(CH₂)_nSO₃⁻

Na⁺ wherein n=1-6, R₄=H;

(e) R₂=(CH₂)_nSO₃⁻

Na⁺ wherein n=1-6, R₄=(CH₂)_nSO₃⁻

Na⁺ wherein n=1-6;

(f) R₂=(CH₂)_nOR₆ wherein n=0-4 and R₆=(i) H or (ii) (CH₂)_mCH3 wherein m=0-4, R₄=H;

or (g) R₂=(CH₂)_nOR₆ wherein n=0-4 and R₆=(i) H or (ii) (CH₂)_mCH3 wherein m=0-4, R₄=(CH₂)_nOR₆ wherein n=0-4 and R₆=(i) H or (ii) (CH₂)_mCH₃ wherein m=0-4.

14. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is of the formula

wherein each of R₁, R₂, R₃, and R₄, independently of the others, is a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, an olkylaryloxy group, or a heterocyclic group, D⁻

is a dopant moiety, and n is an integer representing the number of repeat monomer units.

15. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) has at least about 3 repeat monomer units.

16. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) has at least about 6 repeat monomer units and wherein the poly(3,4-ethylenedioxythiophene) has no more than about 100 repeat monomer units.

17. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is doped with iodine, molecules containing sulfonate groups, molecules containing phosphate groups, molecules containing phosphonate groups, or mixtures thereof.

18. A toner according to claim 1 wherein the poly(3,3-ethylenedioxythiophene) is doped with sulfonate containing anions of the formula RSO₃—

wherein R is an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, an alkylaryloxy group, or mixtures thereof.

19. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is doped with anions selected from p-toulene sulfonate, camphor sulfonate, benzene sulfonate, naphthalene sulfonate, dodecyl sulfonate, dodecylbenzene sulfonate, dialkyl benzenealkyl sulfonates, para-ethylbenzene sulfonate, alkyl naphthalene sulfonates, poly(styrene sulfonate), or mixtures thereof.

20. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is doped with anions selected from p-toulene sulfonate, camphor sulfonate, benzene sulfonate, naphthalene sulfonate, dodecyl sulfonate, dodecylbenzene sulfonate, 1,3-benzene disulfonate, para-ethylbenzene sulfonate, 1,5-naphthalene disulfonate, 2-naphthalene disulfonate, poly(styrene sulfonate), or mixtures thereof.

21. A toner according to claim 1 wherein the poly(3,4-ethylenedioxythiophene) is present in an amount of at least about 5 weight percent of the toner particle mass and wherein the poly(3,4-ethylenedioxythiophene) is present in an amount of no more than about 20 weight percent of the toner particle mass.

22. A toner according to claim 1 wherein the toner particles have an average particle diameter of no more than about 10 microns.

23. A toner according to claim 1 wherein the toner particles have a particle size distribution of GSD equal to no more than about 1.25.

24. A toner according to claim 1 wherein the toner particles have an average bulk conductivity of no more than about 10⁻

12 Siemens per centimeter.

25. A toner according to claim 1 wherein the toner particles have an average bulk conductivity of no more than about 10⁻

13 Siemens per centimeter, and wherein the toner particles have an average bulk conductivity of no less than about 10<sup>−

16</sup> Siemens per centimeter.

26. A toner according to claim 1 wherein the toner particles have an average bulk conductivity of no less than about 10⁻

11 Siemens per centimeter.

27. A toner according to claim 1 wherein the toner particles have an average bulk conductivity of no less than about 10⁻

7 Siemens per centimeter.

28. A toner according to claim 1 wherein said toner particles are nonmagnetic.

30. A toner according to claim 23 wherein the polyester resin is polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polypentylene terephthalate, polyhexalene terephthalate, polyheptadene terephthalate, polyoctalene-terephthalate, poly(propylene-diethylene terephthalate), poly(bisphenol A-fumarate), poly(bisphenol A-terephthalate), copoly(bisphenol A-terephthalate)-copoly(bisphenol A-fumarate), poly(neopentyl-terephthalate), or mixtures thereof.

29. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein the poly(3,4-ethylenedioxythiophene) is doped with a dopant present in an amount of at least about 0.1 molar equivalent of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer and present in an amount of no more than about 5 molar equivalents of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer.

31. A toner according to claim 29 wherein the poly(3,4-ethylenedioxythiophene) is doped with a dopant present in an amount of at least about 0.25 molar equivalent of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer and present in an amount of no more than about 4 molar equivalents of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer.

32. A toner according to claim 29 wherein the poly(3,4-ethylenedioxythiophene) is doped with a dopant present in an amount of at least about 0.5 molar equivalent of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer and present in an amount of no more than about 3 molar equivalents of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer.

33. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles ore prepared by on emulsion aggregation process, wherein the toner particles comprise a core comprising the polyester resin and optional colorant, said core having a surface, and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the polyester resin is a sulfonated polyester resin, and wherein the sulfonated polyester resin anchors the poly(3,4-ethylenedioxythiophene) to the core surface.

34. A toner according to claim 33 wherein the sulfonated polyester resin is a salt of a poly(1,2-propylene-5-sulfoisophthalate), a poly(neopentylene-5-sulfoisophthalate), a poly(diethylene-5-sulfoisophthalate), a copoly(1,2-propylene-5-sulfoisophthalate)-copoly-(1,2-propylene-terephthalate phthalate), a copoly(1,2-propylene-diethylene-5sulfoisophthalate)-copoly-(1,2-propylene-diethylene-terephthalate phthalate), a copoly(ethylene-neopentylene-5-sulfoisophthalate)-copoly-(ethylene-neopentylene-terephthalate-phthalate), a copoly(propoxylated bisphenol A)-copoly-(propoxylated bisphenol A-5-sulfoisophthalate), a copoly(ethylene-terephthalate)-copoly-(ethylene-5-sulfo-isophthalate), a copoly(propylene-terephthalate)-copoly-(propylene-5-sulfo-isophthalate), a copoly(diethylene-terephthalate)-copoly-(diethylene-5-sulfo-isophthalate), a copoly(propylene-diethylene-terephthalate)-copoly-(propylene-diethylene-5-sulfoisophthalate), a copoly(propylene-butylene-terephthalate)-copoly(propylene-butylene-5-sulfo-isophthalate), a copoly(propoxylated bisphenol-A-fumarate)-copoly(propoxylated bisphenol A-5-sulfoisophthalate), a copoly(ethoxylated bisphenol-A-fumarate)-copoly(ethoxylated bisphenol-A-5-sulfo-isophthalate), a copoly(ethoxylated bisphenol-A-maleate)-copoly(ethoxylated bisphenol-A-5-sulfo-isophthalate), a copoly(propylene-diethylene terephthalate)-copoly(propylene-5-sulfoisophthalate), a copoly(neopentyl-terephthalate)-copoly-(neopentyl-5-sulfoisophthalate), or a mixture thereof.

35. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein the emulsion aggregation process comprises (1) shearing a first ionic surfactant with a latex mixture comprising (a) a counterionic surfactant width a charge polarity of opposite sign to that of said first ionic surfactant, (b) a nonionic surfactant, and (c) the polyester resin, thereby causing flocculation or heterocoagulation of formed particles of resin to form electrostatically bound aggregates;

and (2) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter, wherein the toner particles comprise a core comprising the polyester resin and optional colorant, said core having a surface, and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the ionic surfactant has a sulfonate group thereon, wherein the ionic surfactant remains on the core surface, and wherein the ionic surfactant acts as a dopant for the poly(3,4-ethylenedioxythiophene).

36. A toner comprising particles of a polyester resin, a colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by on emulsion aggregation process, wherein the emulsion aggregation process comprises (1) preparing a colorant dispersion in a solvent, which dispersion comprises the colorant and a first ionic surfactant;

(2) shearing the colorant dispersion with a latex mixture comprising (a) a counterionic surfactant with a charge polarity of opposite sign to that of said first ionic surfactant, (b) a nonionic surfactant, and (c) the polyester resin, thereby causing flocculation or heterocoagulation of formed particles of colorant and resin to form electrostatically bound aggregates; and

(3) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter, wherein the toner particles comprise a core comprising the polyester resin and colorant, said core having a surface, and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the ionic surfactant has a sulfonate group thereon, wherein the ionic surfactant remains on the core surface, and wherein the ionic surfactant acts as a dopant for the poly(3,4-ethylenedioxythiophene).

37. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein the emulsion aggregation process comprises (1) shearing an ionic surfactant with a latex mixture comprising (a) a flocculating agent, (b) a nonionic surfactant, and (c) the polyester resin, thereby causing flocculation or heterocoagulation of formed particles of resin to form electrostatically bound aggregates;

and (2) heating the electrostatically bound aggregates to form a aggregates of at least about 1 micron in average particle diameter, wherein the toner particles comprise a core comprising the polyester resin and optional colorant, said core having a surface, and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the ionic surfactant has a sulfonate group thereon, wherein the ionic surfactant remains on the core surface, and wherein the ionic surfactant acts as a dopant for the poly(3,4-ethylenedioxythiophene).

38. A toner comprising particles of a polyester resin, a colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein the emulsion aggregation process comprises (1) preparing a colorant dispersion in a solvent, which dispersion comprises the colorant and an ionic surfactant;

(2) shearing the colorant dispersion with a latex mixture comprising (a) a flocculating agent, (b) a nonionic surfactant, and (c) the polyester resin, thereby causing flocculation or heterocoagulation of formed particles of colorant and resin to form electrostatically bound aggregates; and

(3) heating the electrostatically bound aggregates to form aggregates of at least about 1 micron in average particle diameter, wherein the toner particles comprise a core comprising the polyester resin and colorant, said core having a surface, and, coated on the core, a coating comprising the poly(3,4-ethylenedioxythiophene), wherein the ionic surfactant has a sulfonate group thereon, wherein the ionic surfactant remains on the core surface, and wherein the ionic surfactant acts as a dopant for the poly(3,4-ethylenedioxythiophene).

39. A toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxythiophene), wherein said toner particles are prepared by an emulsion aggregation process, wherein said poly(3,4-ethylenedioxythiophene) has no more than about 100 repeat monomer units, wherein the poly(3,4-ethylenedioxythiophene) is doped with a dopant present in an amount of at least about 0.1 molar equivalent of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer and present in an amount of no more than about 5 molar equivalents of dopant per molar equivalent of 3,4-ethylenedioxythiophene monomer, wherein said poly(3,4-ethylenedioxythiophene) has at least about 3 repeat monomer units.

40. A toner according to claim 39 wherein said poly(3,4-ethylenedioxythiophene) has at least about 6 repeat monomer units.