Toner particles of controlled morphology

• US 6,482,562 B2
• Filed: 08/31/2001
• Issued: 11/19/2002
• Est. Priority Date: 03/10/1999
• Status: Expired due to Fees

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Ezenyilimba, Matthew C., Regan, Michael T., Zion, Todd C., Smith, Dennis E., Yoon, Hichang
• Primary Examiner(s): Dote, Janis L.
• Application Number:
  US09/944,583
• Publication Number:
  US 20020068233A1
• Time in Patent Office: 445 Days
• Field of Search: 430/137.1, 430/137.14, 430/137.19, 430/137
• US Class Current: 430/137.14
• CPC Class Codes: G03G 9/08 with toner particles
• CPC Class Codes: G03G 9/0804 whereby the components are brought together in a liquid dispersing medium

Abstract

A method for the preparation of electrostatographic toner comprising the steps of: a) dissolving a polymer material in an organic solvent to form an organic phase; b) dispersing the organic phase in an aqueous phase comprising a particulate stabilizer to form a dispersion and homogenizing the resultant dispersion wherein a flocculating agent is added to the aqueous phase before or after homogenization; c) evaporating the organic solvent and recovering a resultant product; and d) washing and drying the resultant product.

Claims

1. A method for the preparation of electrostatographic toner comprising the steps of:

A) dissolving a polymer material in an organic solvent to form an organic phase;

B) dispersing the organic phase in an aqueous phase comprising a flocculating agent and a particulate stabilizer to form a dispersion and homogenizing the resultant dispersion, wherein the particulate stabilizer is selected from the group consisting of highly cross-linked latex polymeric material, and SiO₂ and wherein flocculating agent is a cationic compound that is an ammonium salt having the general form

 

where X is H₂PO₄, OH, or Cl, each R₁ is individually selected from the form (CH₂)_nY, where Y is either

 

or —

H, and R₂ has the form (CH₂)_nZ, where Z is —

NHOOC(CH₂)_pCH₃, each n is individually selected from the integers ranging from 0 to 5, and each p is individually selected from an integer from 0 to 20;

or said cationic flocculating agent is a product of condensation polymerization between one or more dicarboxylic acids and an aminoalcohol, diamine, or diol, wherein at least one group contained in an organic dicarboxylic acid chain carries a positive charge, thereby forming dispersed particles, and

C) evaporating the organic solvent from the dispersed particles formed in step (B) and recovering resultant product.

2. The method of claim 1 wherein the polymer material is selected from the group consisting of polyethylene, polypropylene, polyisobutylene, polyisopentylene, polytrifluorolefins, polyamides, acrylic resins, ethylene-methylacrylate copolymers, ethylene-ethyl acrylate copolymers, ethylene-ethyl methacrylate copolymers, polystyrene and copolymers of styrene with unsaturated monomers, polyesters, polyvinyl resins and ethylene-vinyl alcohol copolymers.

3. The method of claim 1 wherein a charge control agent is added in step (A).

4. The method of claim 1 wherein a pigment is added in step (A).

5. The method of claim 1 wherein a promoter is added in the dispersing step in (B).

6. The method of claim 1 wherein the solvent is selected from the group consisting of chloromethane, dichloromethane, ethyl acetate, n-propyl acetate, iso-propyl acetate, vinyl chloride, trichloromethane, carbon tetrachloride, ethylene chloride, trichloroethane, toluene, xylene, cyclohexanone and 2-nitropropane.

7. The method of claim 1 wherein the amount of particulate stabilizer is between 1 to 15 parts based by weight on 100 parts of total solids in the toner.

8. The method of claim 1 wherein the ratio of the aqueous phase to the organic phase, by volume, ranges from 1:

1 to. 9;

1.

9. The method of claim 1 wherein the organic phase contains lubricants.

10. The method of claim 1 wherein the organic phase contains waxes.

11. The method of claim 1 wherein the polymer material is selected from the group consisting of polytetrafluoroethylene, polytrifluorochloroethylene, polyhexamethylene adipamide, polyhexamethylene sebacamide, polycaprolactam, polymethylmethacrylate, polymethylacrylate, polyethylmethacrylate and styrene-methylmethacrylate.

12. The method of claim 1 wherein the polymer material is polyester.

13. The method of claim 1 wherein the polymer material is butyl acrylate-styrene copolymer.