Inverse emulsion acrylate ink compositions for ink-based digital lithographic printing

Patent metadata

Field	Value
Publication number	US-10113076-B2
Application number	US-201414501071-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2014
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

The disclosed embodiments are directed to a composition of an inverse emulsion acrylate ink for use in variable data digital lithographic image forming devices and methods for preparing and using the ink. The disclosed inverse emulsion acrylate ink includes an acrylate monomer, oligomer, polymer, or mixtures thereof that is a continuous phase, and water dispersed as an emulsion in the continuous acrylate phase. The disclosed inverse emulsion acrylate ink includes one or more of a color pigment component, a rheology modifying agent, a stabilizing agent, and a photoinitiator component. The water may be supplemented with a surfactant to lower a surface tension of the water.

First claim

What is claimed is:

1. An ink composition useful for variable data digital lithographic printing, comprising:
an acrylate ink base formulation comprising:
a) a color pigment component,
b) at least one of an acrylate monomer, oligomer or polymer, or a mixture thereof, forming a continuous acrylate phase, and
c) a free radical photoinitiator component comprising at least one of a type I photoinitiator and a type II photoinitiator; and

an aqueous solution consisting of water and a single surfactant in an amount of from about 1.0 ppm to about 2.0 ppm, wherein the aqueous solution is dispersed in the continuous acrylate phase of the acrylate ink base to provide an inverse emulsion ink composition having a viscosity in the range of from about 1E+05 centipoise to about 1E+06 centipoise at a temperature of from about 20 degrees Celsius to about 50 degrees Celsius,
wherein the surfactant lowers a surface tension of the water to below a surface tension of the acrylate ink base formulation, and
wherein the at least one of the acrylate monomer, oligomer or polymer, or a mixture thereof comprises a high-viscosity, di-functional acrylated polyester oligomer.

2. The ink composition of claim 1 , wherein the acrylate ink base formulation further comprises:
a rheology modifying agent; and
a UV stabilizing agent.

3. The ink composition of claim 1 , wherein the inverse emulsion comprises 5% or less by weight of the aqueous solution.

4. The ink composition of claim 1 , wherein the ink composition comprises a total water content in an amount ranging from about 1% to about 10%.

5. The ink composition of claim 1 , wherein a shear thinning index (50/5) of the ink composition is from about 0.35 to about 0.65.

6. A method for preparing an ink composition for use in digital printing, comprising:
a) preparing an acrylate ink base formulation comprising mixing a color pigment component and a free radical photoinitiator component with at least one of an acrylate monomer, acrylate oligomer, acrylate polymer or a mixture thereof, wherein the free radical photoinitiator component comprises at least one of a type I photoinitiator and a type II photoinitiator, wherein at least one of an acrylate monomer, acrylate oligomer, acrylate polymer or a mixture thereof forms a continuous acrylate phase; and
b) preparing an aqueous solution by mixing water and a single surfactant and
c) dispersing the aqueous solution in the continuous acrylate phase of the acrylate ink base to form an inverse emulsion ink composition having a viscosity in the range of from about 1E+05 centipoise to about 1E+06 centipoise at a temperature of from about 20 degrees Celsius to 50 degrees Celsius,
wherein the inverse emulsion comprises a total water content in an amount ranging from about 1% to about 10% and
wherein the at least one of the acrylate monomer, oligomer or polymer, or a mixture thereof comprises a high-viscosity, di-functional acrylated polyester oligomer.

7. The method of claim 6 , wherein the at least one acrylate monomer, acrylate oligomer, acrylate polymer or the mixture thereof constitutes a continuous phase and the aqueous solution is dispersed as an emulsified liquid within the continuous phase.

8. The method of claim 6 , wherein preparing the acrylate ink base formulation further comprises introducing at least one of a rheology modifying agent and a stabilizing agent into the acrylate ink base formulation.

9. The method of claim 6 , wherein the surfactant lowers the surface tension of the water to below a surface tension of the acrylate ink base formulation.

10. The method of claim 6 , wherein a shear thinning index (50/5) of the ink composition is from about 0.35 to about 0.65 after evaporating water from the ink composition.

11. An ink composition useful for variable data digital lithographic printing, comprising:
an acrylate ink base formulation comprising:
a) a color pigment component,
b) at least one of an acrylate monomer, oligomer or polymer, or a mixture thereof, forming a continuous acrylate phase, and
c) a free radical photoinitiator component comprising at least one of a type I photoinitiator and a type II photoinitiator; and

an aqueous solution comprising water and from 0.5 ppm to 2 ppm of a single surfactant, wherein said aqueous solution is dispersed in the continuous acrylate phase of the acrylate ink base to provide an inverse emulsion ink composition having a viscosity in the range of from about 1E+05 centipoise to about 1E+06 centipoise at a temperature of from 20 degrees Celsius to 50 degrees Celsius,
wherein the inverse emulsion comprises 5% or less by weight of the aqueous solution, and
wherein the at least one of the acrylate monomer, oligomer or polymer, or a mixture thereof comprises a high-viscosity, di-functional acrylated polyester oligomer.

12. The ink composition of claim 11 , wherein the surfactant lowers a surface tension of the water to below a surface tension of the acrylate ink base formulation.

13. The ink composition of claim 11 , wherein the ink composition comprises a total water content in an amount ranging from about 1% to about 10%.

14. The ink composition of claim 1 , wherein the acrylate ink base formulation comprises more than one of the acrylate monomer, oligomer and polymer.

15. The ink composition of claim 1 , wherein the high-viscosity di-functional acrylated polyester oligomer has a viscosity of at least 11,000 cps at 60° C.

16. The ink composition of claim 1 wherein the high-viscosity di-functional acrylated polyester oligomer has a viscosity of at least 11,000 cps at 60° C.

Assignees

• Xerox Corp

Inventors

• Moorlag Carolyn
• Breton Marcel
• Allen C Geoffrey
• Eliyahu Jenny

Classifications

• C09D11/104

  Polyesters · CPC title

• B41M5/395

  Macromolecular additives, e.g. binders · CPC title

• C09D11/107 Primary

  from unsaturated acids or derivatives thereof · CPC title

• C09D11/023 Primary

  Emulsion inks · CPC title

• C09D11/106

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