Method of Making a Core Shell Toner Formulation Including a Styrene Acrylate Polyester Copolymer Used for the Shell

Patent metadata

Field	Value
Publication number	US-2017010547-A1
Application number	US-201514795196-A
Country	US
Kind code	A1
Filing date	Jul 9, 2015
Priority date	Jul 9, 2015
Publication date	Jan 12, 2017
Grant date	—

Abstract

The present invention relates generally to methods to make a chemically prepared toner having a core shell structure for use in electrophotography and more particularly to a method to make an emulsion aggregation chemically prepared core shell toner formulation using a styrene acrylic polyester copolymer for the shell. The styrene acrylic polyester copolymer has a glass transition temperature (Tg) between 55° C. to 65° C., a melt temperature (Tm) between 100° C. to 130° C., a peak molecular weight of about 12,000 and acid value from 10-28.

First claim

What is claimed is:

1 . A method for producing toner, comprising:
combining and agglomerating a first polymer emulsion with a colorant dispersion and a release agent dispersion to form toner cores; adding a borax coupling agent to the toner cores;
combining and agglomerating a second polymer emulsion including a styrene acrylic polyester copolymer with the toner cores having the borax coupling agent to form toner shells around the toner cores; and
fusing the aggregated toner cores and toner shells to form toner particles.

2 . The method of producing toner of claim 1 , wherein the first polymer emulsion include polyester resin or a mixture of different polyester resins.

3 . The method of producing toner of claim 1 , wherein the first polymer emulsion is a styrene acrylate resin or a mixture of different styrene acrylate resins.

4 . The method of producing toner of claim 1 , wherein the first polymer emulsion is a mixture including a styrene acrylate resin and a polyester resin or a mixture of multiple polyester and styrene acrylic resins.

5 . The method of producing toner of claim 1 , wherein the second polymer emulsion including a styrene acrylic polyester copolymer has a glass transition temperature (Tg) between 55° C. to 65° C.

6 . The method of producing toner of claim 1 , wherein the second polymer emulsion including a styrene acrylic polyester copolymer has a melt temperature (Tm) between 100° C. to 130° C.

7 . The method of producing toner of claim 1 , wherein the second polymer emulsion including a styrene acrylic polyester copolymer has a peak molecular weight of about 12,000.

8 . The method of producing toner of claim 1 , wherein the second polymer emulsion including a styrene acrylic polyester copolymer has an acid value from 10-28.

9 . The method of claim 1 , wherein the borax coupling agent is added to the toner cores once the toner cores reach a predetermined size and added at between about 0.1% and about 5.0% by weight of the total polymer binder content in the first polymer emulsion and the second polymer emulsion.

10 . A method for producing toner, comprising:
combining a first polymer emulsion with a colorant dispersion and a release agent dispersion to form toner cores; adjusting the pH of the combination of the first polymer emulsion, the colorant dispersion and the release agent dispersion to promote agglomeration of the toner cores; once the toner cores reach a predetermined size, adding a borax coupling agent to the toner cores; combining a second polymer emulsion including a styrene acrylic polyester copolymer having a glass transition temperature (Tg) between 55° C. to 65° C., a melt temperature (Tm) between 100° C. to 130° C., a peak molecular weight of about 12,000 and acid value from 10-28 with the toner cores having the borax coupling agent and forming toner shells around the toner cores; once a desired toner particle size is reached, adjusting the pH of the mixture of aggregated toner cores and toner shells to prevent additional particle growth; and fusing the aggregated toner cores and toner shells to form toner particles.

11 . The method of claim 10 , wherein the borax coupling agent is added to the toner cores once the toner cores reach a predetermined size and added at between about 0.1% and about 5.0% by weight of the total polymer binder content in the first polymer emulsion and the second polymer emulsion.

12 . The method of producing toner of claim 10 , wherein the first polymer emulsion is a polyester resin or a mixture of different polyester resins.

13 . The method of producing toner of claim 10 , wherein the first polymer emulsion is a styrene acrylate resin or a mixture of different styrene acrylate resins.

14 . The method of producing toner of claim 10 , wherein the first polymer emulsion is a mixture including a styrene acrylate resin and a polyester resin or a mixture of multiple polyester and styrene acrylic resins.

Assignees

• Lexmark Int Inc

Inventors

• Bejat Ligia Aura
• Marin Goggin Claudia Alexandra
• Hammond Cory Nathan
• Jones Rick Owen
• Mcalpine Robert Watson
• Sun Jing X
• Yaron Peter Nikolaivich

Classifications

• G03G9/0806 Primary

  whereby chemical synthesis of at least one of the toner components takes place · CPC title

• G03G9/09321 Primary

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G9/09371

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G9/09392

  Preparation thereof · CPC title

• G03G9/09328

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title