Toner processes

• US 6,756,176 B2
• Filed: 09/27/2002
• Issued: 06/29/2004
• Est. Priority Date: 09/27/2002
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Stegamat, Reza, Veregin, Richard P. N., Farrugia, Valerie M.
• Primary Examiner(s): Goodrow, John L
• Application Number:
  US10/260,377
• Publication Number:
  US 20040063020A1
• Time in Patent Office: 641 Days
• Field of Search: 430/137.14, 430/137.1
• US Class Current: 430/137.14
• CPC Class Codes: C08G 63/6888 Polycarboxylic acids and polyhydroxy compounds in which at least one of the two components contains aliphatic unsaturation
• CPC Class Codes: C08G 63/916 Dicarboxylic acids and dihydroxy compounds
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08L 21/00 Compositions of unspecified rubbers
• CPC Class Codes: C08L 2666/08 Homopolymers or copolymers according to C08L7/00 - C08L21/00; Derivatives thereof
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: G03G 9/0804 whereby the components are brought together in a liquid dispersing medium
• CPC Class Codes: G03G 9/0815 Post-treatment
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/09783 Organo-metallic compounds

Abstract

A process comprising heating a resin latex and a colorant below about the glass transition temperature (Tg) of the resin; adding a metal stearate; and isolating the product; and wherein the heating generates an alkyl carboxylate metal salt component ionically attached to the surface of the product.

Claims

1. A process comprising heating a sulfonated polyester resin latex and a colorant below about the glass transition temperature (Tg) of the sulfonated polyester resin, adding a metal stearate to the resulting slurry, and isolating the product, and wherein said heating generates an alkyl carboxylate metal salt component ionically attached to the surface of said product.

2. A process in accordance with claim 1 wherein said latex is an emulsion comprised of resin, water, and an ionic surfactant, and wherein said colorant is a dispersion containing a colorant, water, and an ionic surfactant.

3. A process in accordance with claim 1 wherein said resin is comprised of a colloidal solution of said sulfonated polyester resin and water, and further including an aqueous solution selected from the group consisting of an alkaline earth metal (II) salt and a transition metal salt to coalesce and ionically complex the sulfonated polyester colloid, colorant, and metal cation resulting from said alkaline earth metal or said transition metal salt.

4. A process in accordance with claim 1 wherein said metal stearate is calcium stearate selected in an amount of from about 0.005 to about 5 weight percent, and wherein said alkyl carboxylate metal salt is calcium carboxylate.

5. A process in accordance with claim 1 wherein said stearate is selected in an amount of from about 0.005 to about 3 weight percent.

6. A process in accordance with claim 1 wherein said stearate is calcium stearate selected in an amount of from about 0.05 to about 1 weight percent.

7. A process in accordance with claim 1 wherein said stearate is calcium stearate added in the form of a fine powder.

8. A process in accordance with claim 1 wherein said stearate is calcium stearate added to the mixture followed by heating.

9. A process in accordance with claim 8 wherein said heating is from about 35°

C. to about 50°

C.

10. A process in accordance with claim 8 wherein said heating is from about 35°

C. to about 45°

C.

11. A process in accordance with claim 8 wherein said calcium stearate is added from a dilute solution thereof.

12. A process in accordance with claim 11 wherein said diluted solution is added at a rate of about 0.5 to about 2 milliliters per minute for each 100 grams of toner solids of resin and colorant.

13. A process in accordance with claim 1 wherein said heating is at about 40°

C., and said stearate is added at a rate of about 0.7 milliliter per minute for each 100 grams of toner solids of resin and colorant.

14. A process in accordance with claim 1 wherein the polyester is present in an amount of from about 80 to about 98 percent by weight of said product and which product is a toner;

the colorant is present in an amount of from about 2 to about 20 weight percent of the toner, and the alkyl carboxylate component is present in an amount of from about 0.005 to about 5 weight percent of the toner.

15. A process in accordance with claim 1 wherein there is added to the mixture a second latex, and which latex is comprised of submicron resin particles suspended in an aqueous phase containing an ionic surfactant, and wherein said second latex is optionally selected in an amount of about 10 to about 40 percent by weight of the initial latex.

16. A process in accordance with claim 1 comprising (i) preparing a colloidal solution of a sulfonated polyester resin by heating in water at a temperature of from about 75°

C. to about 95°

C., and cooling;

(ii) adding thereto a colorant, followed by heating the resulting mixture to a temperature above the polyester resin glass transition temperature;

(iii) adding thereto an aqueous solution of alkaline earth metal (ii) salt or a transition metal salt whereby the coalescence and ionic complexation of sulfonated polyester colloid, colorant, and metal cation is accomplished; and

(iv) chemically treating said resulting toner particles in the resulting heated aqueous slurry at a temperature of about 25°

C. to about 60°

C. with an aqueous solution of said alkyl carboxylate salt which is present in an amount of from about 0.005 to about 5 weight percent of the toner.

17. A process in accordance with claim 1 wherein said temperature below about said sulfonated polyester resin is from about 40°

C. to about 60°

C., thereby resulting in toner aggregates, further heating above about said sulfonated polyester resin Tg, and which heating is from about 65°

C. to about 75°

C.

18. A process in accordance with claim 17 wherein the temperature at which the aggregation is accomplished controls the size of the aggregates, and wherein the product is a toner and is from about 2 to about 15 microns in volume average diameter.

19. A process in accordance with claim 1 wherein the colorant is a pigment.

20. A process in accordance with claim 1 wherein the latex further contains a resin selected from the group consisting of poly(styrene-butadiene), poly(methylstyrene-butadiene), poly(methyl methacrylate-butadiene), poly(ethyl methacrylate-butadiene), poly(propyl methacrylate-butadiene), poly(butyl methacrylate-butadiene), poly(methyl acrylate-butadiene), poly(ethyl acrylate-butadiene), poly(propyl acrylate-butadiene), poly(butyl acrylate-butadiene), poly(styrene-isoprene), poly(methylstyrene-isoprene), poly(methyl methacrylate-isoprene), poly(ethyl methacrylate-isoprene), poly(propyl methacrylate-isoprene), poly(butyl methacrylate-isoprene), poly(methyl acrylate-isoprene), poly(ethyl acrylate-isoprene), poly(propyl acrylate-isoprene), poly(butyl acrylate-isoprene);

poly(styrene-propyl acrylate), poly(styrene-butyl acrylate), poly(styrene-butadiene-acrylic acid), poly(styrene-butadiene-methacrylic acid), poly(styrene-butadiene-acrylonitrile-acrylic acid), poly(styrene-butyl acrylate-acrylic acid), poly(styrene-butyl acrylate-methacrylic acid), poly(styrene-butyl acrylate-acrylononitrile), and poly(styrene-butyl acrylate-acrylononitrile-acrylic acid).

21. A process in accordance with claim 1 wherein the sulfonated polyester (i) is a polyester of poly(1,2-propylene-sodio 5-sulfoisophthalate), poly(neopentylene-sodio 5-sulfoisophthalate), poly(diethylene-sodio 5-sulfoisophthalate), copoly-(1,2-propylene-sodio 5-sulfoisophthalate)-copoly-(1,2-propylene-terephthalatephthalate), copoly-(1,2-propylene-diethylenesodio 5-sulfoisophthalate)-copoly-(1,2-propylene-diethylene-terephthalatephthalate), copoly-(ethylene-neopentylene-sodio or copoly-(propoxylated bisphenol A)-copoly-(propoxylated bisphenol A-sodio 5-sulfoisophthalate).

22. A process in accordance with claim 1 wherein the colorant is carbon black, cyan, yellow, magenta, or mixtures thereof, and the product isolated is a toner of from about 2 to about 25 microns in volume average diameter, and the particle size distribution thereof is optionally from about 1.15 to about 1.30;

and wherein there is added to the surface of the formed toner metal salts, metal salts of fatty acids, silicas, metal oxides, or mixtures thereof, each in an amount of from about 0.1 to about 10 weight percent of the obtained toner.

31. A process in accordance with claim 1 wherein said stearate is calcium stearate, or magnesium stearate.

32. A process in accordance with claim 1 wherein said stearate is aluminum stearate.

33. A process in accordance with claim 1 wherein said alkyl carboxylate is sodium octanoate, lithium palmitate, magnesium stearate, sodium palmitate, calcium 2-ethylhexanoate, sodium butyrate or calcium propionate.

34. A process in accordance with claim 1 wherein said polyester resin is poly(1,2-propylene-sodio 5-sulfoisophthalate).

35. A process in accordance with claim 1 wherein said polyester resin is polyneopentylene-sodio 5-sulfoisophthalate polyester.

38. A process in accordance with claim 1 wherein said product is a toner, and which toner is comprised of said sulfonated polyester resin, said colorant, and said alkyl carboxylate metal salt.

40. A process in accordance with claim 1 wherein said product is a toner and wherein said sulfonated polyester is of the formula

wherein Y is an alkali metal, X is a glycol, and n and m each represent the number of segments.

23. A toner process comprising mixing a sulfonated polyester resin with a colorant;

heating the resulting mixture below the glass transition temperature (Tg) of the sulfonated polyester resin;

heating above the Tg of the sulfonated polyester resin; and

subsequently adding a metal stearate.

24. A process in accordance with claim 23 wherein said colorant is a mixture comprised of about 20 to about 60 weight percent solids of resin and colorant, and which resin is a latex dispersion, and wherein there results a toner containing as an ionically complexed surface additive said stearate.

25. A process in accordance with claim 23 wherein said stearate is calcium stearate.

26. A process in accordance with claim 23 wherein said stearate is magnesium stearate.

27. A process in accordance with claim 23 wherein said stearate is aluminum stearate.

28. A process in accordance with claim 23 wherein said stearate is zinc stearate.

29. A process in accordance with claim 24 wherein said ionically complexed additive is an alkylcarboxylate.

30. A process in accordance with claim 23 wherein said metal stearate is an alkaline earth salt.

36. A process comprising heating a polyester resin, colorant and a metal stearate, which heating includes a first heating at a temperature below the Tg of said resin, and a second heating above the Tg of the polyester resin;

and thereafter optionally isolating the product.

37. A process in accordance with claim 36 wherein said product is a toner, and which toner is isolated.

39. A process in accordance with claim 36 wherein said product is a toner, and which toner is comprised of said sulfonated polyester resin, said colorant, and said alkyl carboxylate metal salt.