Preparation method of a polyester particle dispersion and polyester particle dispersion prepared by the same

• US 20060115759A1
• Filed: 09/16/2005
• Published: 06/01/2006
• Est. Priority Date: 11/26/2004
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Young-ho, Kim, Sang-woo, Oh, Seong-geun
• Application Number:
  US11/227,083
• Publication Number:
  US 20060115759A1
• Time in Patent Office: Days
• US Class Current: 430/109.400
• CPC Class Codes: G03G 9/0806 whereby chemical synthesis of at least one of the toner components takes place
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/08762 Other polymers having oxygen as the only heteroatom in the main chain
• CPC Class Codes: G03G 9/08791 characterised by the presence of specified groups or side chains
• CPC Class Codes: G03G 9/08793 Crosslinked polymers
• CPC Class Codes: G03G 9/08795 characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants
• CPC Class Codes: G03G 9/08797 characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature

Abstract

A preparation method of a polyester particle dispersion includes: under predetermined depolymerization conditions, mixing a polyester binder resin, a resin dissolvent and a polycondensation catalyst to depolymerize the polyester resin and form a first reaction mixture; adding a first monomer to the first reaction mixture to form a second reaction mixture; under predetermined polymerization conditions, adding a second monomer to the second reaction mixture to polymerize the depolymerized polyester resin and form a third reaction mixture; adding a neutralizing agent to neutralize the polymerized reaction product of the third reaction mixture; (e) adding a reverse-neutralizing agent to reverse neutralize the neutralized mixture; and adding a mixture of an anionic surfactant and a nonionic surfactant to the reverse-neutralized mixture.

Claims

1. A preparation method of a polyester particle dispersion, the method comprising:

under predetermined depolymerization conditions, mixing a polyester resin, a resin dissolvent and a polycondensation catalyst to depolymerize the polyester resin to form a first reaction mixture;

adding a first monomer to the first reaction mixture to form a second reaction mixture;

under predetermined polymerization conditions, adding a second monomer to the second reaction mixture to polymerize the depolymerized polyester resin with the first and second monomers to form a polymerized reaction product;

adding a neutralizing agent to neutralize the polymerized reaction product and form a neutralized mixture;

adding a reverse-neutralizing agent to reverse neutralize the neutralized mixture and form a reverse neutralized mixture; and

adding a mixture of an anionic surfactant and a nonionic surfactant to the reverse-neutralized mixture.

2. The method according to claim 1, wherein the polyester resin is selected from the group consisting of bisphenol A polyester resins and polyethylene terephthalate (PET) polyester resins.

3. The method according to claim 1, wherein the resin dissolvent is selected from the group consisting of gum rosins, wood rosins, tall rosins, rosin esters, and C₅ to C₉ petroleum resins.

4. The method according to claim 1, wherein the polycondensation catalyst is dibutyltinoxide (DBTO).

5. The method according to claim 1, wherein the first and second monomers are polycondensing monomers.

6. The method according to claim 1, wherein the first monomer is selected from the group consisting of maleic acid, phthalic anhydride, isophthalic acid, and terephthalic acid.

7. The method according to claim 1, wherein the second monomer is selected from the group consisting of ethylene glycol, propylene glycol, and bisphenol A alkylene oxide.

8. The method according to claim 1, wherein the neutralizing agent is a basic compound.

9. The method according to claim 8, wherein the basic compound is selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, sodium carbonate, and ammonia.

10. The method according to claim 1, wherein a ratio of the resin dissolvent to the polyester resin ranges from 1:

9 to 9;

1 by weight.

11. The method according to claim 1, wherein the reverse-neutralizing agent is an acid.

12. The method according to claim 11, wherein the acid is hydrochloric acid.

13. The method according to claim 1, wherein the anionic surfactant is selected from the group consisting of sodium dodecyl sulfate, sodium 4-dodecylbenzene sulfonate, and sodium polyoxyethylene lauryl ether sulfate.

14. The method according to claim 1, wherein the nonionic surfactant is selected from the group consisting of polyoxylethylene sorbitan monolaurate and alkylaryl polyester alcohol.

15. A polyester particle dispersion obtained by the preparation method of claim 1.

16. The polyester particle dispersion according to claim 15, wherein the polyester particle dispersion has polyester particles with a diameter from about 50 nm to about 400.

17. The polyester particle dispersion according to claim 15, wherein the dispersion has polyester particles with a glass transition temperature in a range from about 40°

C. to about 100°

C.

18. A method of preparing polyester resin particles for a dry toner, comprising:

mixing a polyester binder resin, a resin dissolvent and a polycondensation catalyst to form a mixture to depolymerize the polyester resin, stirring at approximately 150-350 rpm and reacting at a temperature between 235°

C. and 245°

C. for a predetermined period of time until the mixture becomes transparent;

cooling the mixture to a predetermined temperature in a temperature range between 100°

C. and 200°

C. and adding a first monomer;

performing a secondary depolymerization reaction by heating the mixture with the first monomer at approximately 235°

C. to 245°

C. for a predetermined period of time;

forming a polycondensed product by adding a second monomer to the secondary depolymerization reaction and continuing to heat at approximately 235°

C. to 245°

C. for a predetermined period of time;

cooling the polycondensed product to a predetermined temperature in a temperature range between 50°

C. and 100°

C. and adding a basic solution to neutralize the polycondensed product and stirring for less than an hour at about 300-500 rpm; and

adding, to the neutralized polycondensed product, a mixture of an anionic surfactant and a nonionic surfactant, a predetermined amount of acid, and a predetermined amount of distilled water and stirring in a temperature range of 15°

C. to 35°

C. to prepare a dispersion of particles having a predetermined volume average particle diameter.

19. The method according to claim 18, wherein the polyester binder resin is selected from the group consisting of bisphenol A polyester resins and polyethylene terephthalate (PET) polyester resins.

20. The method according to claim 18, wherein the resin dissolvent is selected from the group consisting of gum rosins, wood rosins, tall rosins, rosin esters, and C₅ to C₉ petroleum resins.

21. The method according to claim 18, wherein the polycondensation catalyst is dibutyltinoxide (DBTO).

22. The method according to claim 18, wherein the first and second monomers are polycondensing monomers.

23. The method according to claim 18, wherein the first monomer is selected from the group consisting of maleic acid, phthalic anhydride, isophthalic acid, and terephthalic acid.

24. The method according to claim 18, wherein the second monomer is selected from the group consisting of ethylene glycol, propylene glycol, and bisphenol A alkylene oxide.

25. The method according to claim 18, wherein the basic solution includes a basic compound selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, sodium carbonate, and ammonia.

26. The method according to claim 18, wherein a ratio of the resin dissolvent to the polyester resin ranges from 1:

9 to 9;

1 by weight.

27. The method according to claim 18, wherein the acid is hydrochloric acid.

28. The method according to claim 18, wherein the anionic surfactant is selected from the group consisting of sodium dodecyl sulfate, sodium 4-dodecylbenzene sulfonate, and sodium polyoxyethylene lauryl ether sulfate.

29. The method according to claim 18, wherein the nonionic surfactant is selected from the group consisting of polyoxylethylene sorbitan monolaurate and alkylaryl polyester alcohol.

30. A polyester particle dispersion obtained by the preparation method of claim 18.

31. The polyester particle dispersion according to claim 30, wherein the polyester particle dispersion has particles with a diameter from about 50 nm to about 400 nm.

32. The polyester particle dispersion according to claim 30, wherein the polyester particle dispersion has particles with a glass transition temperature in a range from about 40°

C. to about 100°

C.