Acrylate ink compositions for ink-based digital lithographic printing

Patent metadata

Field	Value
Publication number	US-9416285-B2
Application number	US-201414573913-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Dec 17, 2014
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

An ink composition, including an ink base and a wax emulsion. A viscosity of the ink composition is between 80 Pa·s and 400 Pa·s at 100 rad/s and 25° C., and a tack of the ink composition is between 32 g-m and 45 g-m at 60 seconds. The total wax content of the ink composition is between 1% and 5% by weight, based on a total weight of the ink composition, and the total water content of the ink composition is between 1% and 15% by weight, based on the total weight of the ink composition.

First claim

The invention claimed is:

1. An ink composition, comprising:
an ink base; and
a wax emulsion,
wherein a viscosity of the ink composition is between 80 Pa·s and 400 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is between 32 g-m and 45 g-m at 60 seconds,
wherein a total wax content of the ink composition is between 1% and 5% by weight, based on a total weight of the ink composition, and
wherein a total water content of the ink composition is between 1% and 15% by weight, based on the total weight of the ink composition.

2. The ink composition of claim 1 :
wherein the ink composition has a viscosity between 90 Pa·s and 300 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is between 35 g-m and 40 g-m at 60 seconds,
wherein a total wax content of the ink composition is between 1% and 4%, and wherein a total water content of the ink composition is between 1% and 10%.

3. The ink composition of claim 2 :
wherein the ink composition has a viscosity of about 150 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is about 38 g-m at 60 seconds,
wherein a total wax content of the ink composition is about 2%, and
wherein a total water content of the ink composition is about 5%.

4. The ink composition of claim 3 , wherein the ink base comprises an acrylate and a pigment.

5. The ink composition of claim 4 , wherein the ink base comprises at least one of an acrylate monomer, acrylate polymer, acrylate oligomer, a trifunctional acrylate monomer, a polyester acrylate, and mixtures thereof.

6. The ink composition of claim 5 , wherein the wax emulsion comprises at least one of a polyethylene wax emulsion, a polypropylene wax emulsion, a carnauba wax emulsion, a paraffin wax emulsion, an ethylene vinyl acetate wax emulsion, chemically modified analogs thereof, or mixtures thereof.

7. The ink composition of claim 5 , wherein the wax emulsion comprises at least one an acidic, non-ionic polyethylene wax emulsion and a basic, non-ionic wax emulsion of an oxidized high density polyethylene wax.

8. The ink composition of claim 4 , further comprising an aqueous solution, wherein the aqueous solution comprises:
water; and
a surfactant.

9. The ink composition of claim 8 , wherein the surfactant comprises at least one of a water-dispersible silicone surfactant, a fluorosurfactant, a coalescing surfactant, and mixtures thereof.

10. The ink composition of claim 8 , further comprising at least one of stabilizers, dispersants, photoinitiators, and rheology additives.

11. The ink composition of claim 1 , further comprising at least one of water, surfactants, stabilizers, dispersants, photoinitiators, pigments, acrylates, and rheology additives, and
wherein the surfactant lowers the surface tension of the aqueous solution to below a surface tension of at least one of the ink base and a mixture of the ink base and the wax emulsion.

12. A method of preparing an ink composition, comprising:
preparing an ink base; and
mixing a wax emulsion with the ink base,
wherein a viscosity of the ink composition is between 80 Pa·s and 400 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is between 32 g-m and 45 g-m at 60 seconds,
wherein a total wax content of the ink composition is between 1% and 5% by weight, based on a total weight of the ink composition, and
wherein a total water content of the ink composition is between 1% and 15% by weight, based on the total weight of the ink composition.

13. The method of claim 12 , further comprising:
dispersing an aqueous solution to the mixture of the ink base and wax emulsion,
wherein the aqueous solution comprises water and a surfactant, and
wherein the aqueous solution is dispersed in the ink composition an inverse emulsion.

14. The method of claim 13 :
wherein the ink composition has a viscosity between 90 Pa·s and 300 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is between 35 g-m and 40 g-m at 60 seconds,
wherein a total wax content of the ink composition is between 1% and 4%, and
wherein a total water content of the ink composition is between 1% and 10%.

15. The method of claim 14 :
wherein the ink composition has a viscosity of about 150 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is about 38 g-m at 60 seconds,
wherein a total wax content of the ink composition is about 2%, and
wherein a total water content of the ink composition is about 5%.

16. The method of claim 14 , wherein the ink base is formed by mixing a pigment composition with at least one of an acrylate monomer, acrylate polymer, acrylate oligomer, a trifunctional acrylate monomer, a polyester acrylate, and mixtures thereof.

17. The method of claim of claim 16 , further comprising introducing at least one of UV stabilizers, dispersants, photoinitiators, and rheology additives to the ink composition.

18. The method of claim 12 , wherein the method further comprises introducing at least one of water, surfactants, UV stabilizers, dispersants, photoinitiators, pigments, acrylates, and rheology additives to the ink composition.

19. A method of printing using a variable data digital lithographic printing device, comprising:
applying an ink composition to a reimageable surface of an imaging member;
evaporating water from the ink composition applied to the reimageable surface of the imaging member; and
transferring the ink composition from the reimageable surface to a substrate,
wherein the ink composition comprises:
an ink base; and
a wax emulsion,
wherein a viscosity of the ink composition is between 80 Pa·s and 400 Pa·s at 100 rad/s and 25° C.,
wherein a tack of the ink composition is between 32 g-m and 45 g-m at 60 seconds,
wherein a total wax content of the ink composition is between 1% and 5% by weight, based on a total weight of the ink composition, and
wherein a total water content of the ink composition is between 1% and 15% by weight, based on the total weight of the ink composition.

20. The method of claim 19 , wherein the ink composition further comprises an aqueous solution, wherein the aqueous solution comprises:
water; and
a surfactant, and
wherein the surfactant lowers the surface tension of the aqueous solution to below a surface tension of at least one of the ink base and a mixture of the ink base and the wax emulsion.

Assignees

• Xerox Corp

Inventors

• Allen C Geoffrey
• Moorlag Carolyn
• Song Guiqin
• Birau Mihaela Maria

Classifications

• C09D11/12 Primary

  based on waxes or bitumen · CPC title

• C09D11/107 Primary

  from unsaturated acids or derivatives thereof · CPC title

• C09D11/037 Primary

  characterised by the pigment · CPC title

• C09D11/03

  characterised by features other than the chemical nature of the binder · CPC title