Microsuspension processes for toner compositions

• US 5,290,654 A
• Filed: 07/29/1992
• Issued: 03/01/1994
• Est. Priority Date: 07/29/1992
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Kmiecik-Lawrynowica, Grazyna, Sacripante, Guerino G., Duff, James M., Patel, Raj D.
• Primary Examiner(s): RODEE, CHRISTOPHER D
• Application Number:
  US07/921,165
• Time in Patent Office: 580 Days
• Field of Search: 430/137, 430/111, 523/322, 523/335, 523/339
• US Class Current: 430/137.14
• CPC Class Codes: C08J 3/215 at least one additive being also premixed with a liquid phase
• CPC Class Codes: G03G 9/0804 whereby the components are brought together in a liquid dispersing medium

Abstract

A process for the preparation of toner compositions which comprises dissolving a polymer, and optionally a pigment in an organic solvent; dispersing the resulting solution in an aqueous media containing a surfactant, or mixture of surfactants; stirring the mixture with optional heating to remove the organic solvent thereby obtaining suspended particles of about 0.05 micron to about 2 microns in volume diameter; subsequently homogenizing the resulting suspension with an optional pigment in water and surfactant; followed by aggregating the mixture by heating thereby providing toner particles with an average particle volume diameter of from between about 3 to about 21 microns when said pigment is present.

Claims

1. A process for the preparation of toner compositions consisting essentially of dissolving a polymer, and a pigment in an organic solvent;

dispersing the resulting solution in an aqueous media containing a surfactant, or mixture of surfactants;

stirring the mixture with optional heating to remove the organic solvent thereby obtaining suspended particles of about 0.05 micron to about 2 microns in volume diameter;

subsequently homogenizing the resulting suspension with pigment in water and surfactant;

followed by aggregating the resulting suspension by heating thereby providing toner particles with an average particle volume diameter of from between about 3 to about 21 microns.

2. A process in accordance with claim 1 wherein the polymer is a styrene acrylate, a styrene methacrylate, a styrene butadiene, or a polyester.

3. A process in accordance with claim 1 wherein the pigment is carbon black, magnetite, or mixtures thereof.

4. A process in accordance with claim 1 wherein the pigment is cyan, magenta, yellow, or mixtures thereof.

5. A process in accordance with claim 1 wherein the organic solvent is an alkylene halide, an ether or an alkyl acetate.

6. A process in accordance with claim 1 wherein the organic solvent is methylene chloride, diethyl ether or ethyl acetate.

7. A process in accordance with claim 6 wherein the surfactant is present in an amount of from about 0.01 to about 3 weight percent.

8. A process in accordance with claim 1 wherein the surfactant is polyethylene oxide, polyacrylic acid, polypropylene oxide, polybutylene oxide, poly(oxyethylene-nonyl phenyl) ether, methyl cellulose, ethyl cellulose, sodium dodecylsulfate, sodium dodecylbenzenesulfonate, dialkylbenzene alkylammonium chloride, or mixtures thereof.

9. A process in accordance with claim 1 wherein the dispersion temperature is from about 20°

C. to about 80°

C.

10. A process in accordance with claim 1 wherein the temperature employed for heating to remove the organic solvent is from about 20°

C. to about 80°

C.

11. A process in accordance with claim 10 wherein the homogenization is for a duration of from about 2 minutes to about 720 minutes.

12. A process in accordance with claim 1 wherein the aggregation temperature is from about 30°

C. to about 95°

C.

13. A process in accordance with claim 1 wherein the homogenization is from about 500 revolutions per minute to about 4,000 revolutions per minute.

14. A process in accordance with claim 1 wherein there is added to the toner product surface additives of metal salts, metal salt of fatty acids, silicas, or mixtures thereof.

15. A process in accordance with claim 1 wherein the amount of the polymer dissolved in the organic solvent is from about 5 to about 95 weight percent.

16. A process for the preparation of toner compositions consisting essentially of dissolving a polymer, in an organic solvent;

dispersing the resulting solution in an aqueous media containing nonionic surfactant;

stirring the mixture with heating to remove the organic solvent thereby obtaining suspended particles of about 0.05 micron to about 2 microns in volume diameter;

subsequently homogenizing the resulting suspension with a pigment in water and nonionic surfactant;

followed by aggregating the suspension by heating thereby providing toner particles with an average particle volume diameter of from between about 3 to about 21 microns.

17. A process in accordance with claim 16 wherein the pigment is carbon black, magnetite, or mixtures thereof;

or cyan, magenta, yellow, or mixtures thereof; and

the surfactant is polyethylene oxide, polyacrylic acid, polypropylene oxide, polybutylene oxide, poly(oxyethylene-nonyl phenyl) ether, methyl cellulose, or ethyl cellulose, sodium dodecylsulfate, chloride, dialkylbenzene alkylammonium chloride, or mixtures thereof.

18. A process for the preparation of toner compositions which comprises dissolving a polymer and a pigment in an organic solvent;

dispersing the resulting solution in an aqueous media containing nonionic surfactant;

stirring the mixture with heating to remove the organic solvent and obtaining suspended particles of about 0.05 micron to about 2 microns in volume diameter;

subsequently homogenizing the resulting suspension with a nonionic surfactant;

followed by aggregating the suspension by heating thereby providing toner particles with an average particle volume diameter of from between about 3 to about 21 microns.

19. A process in accordance with claim 18 wherein the pigment is carbon black, magnetite, or mixtures thereof;

or cyan, magenta, yellow, or mixtures thereof; and

the surfactant is polyethylene oxide, polyacrylic acid, polypropylene oxide, polybutylene oxide, poly(oxyethylene-nonyl phenyl), ether, methyl cellulose, or ethyl cellulose, sodium dodecylsulfate, chloride, dialkylbenzene alkylammonium chloride, or mixture thereof.