Inkjet ink set and method of using same

• US 20040201658A1
• Filed: 01/12/2004
• Published: 10/14/2004
• Est. Priority Date: 01/16/2003
• Status: Abandoned Application

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Jackson, Christian, Wolfe, Michael Stephen
• Application Number:
  US10/755,630
• Publication Number:
  US 20040201658A1
• Time in Patent Office: Days
• US Class Current: 347/100
• CPC Class Codes: B41M 5/0017 Application of ink-fixing material, e.g. mordant, precipitating agent, on the substrate prior to printing, e.g. by ink-jet printing, coating or spraying
• CPC Class Codes: B41M 7/0018 using ink-fixing material, e.g. mordant, precipitating agent, after printing, e.g. by ink-jet printing, coating or spraying
• CPC Class Codes: C09D 11/30 Inkjet printing inks
• CPC Class Codes: C09D 11/40 Ink-sets specially adapted for multi-colour inkjet printing
• CPC Class Codes: C09D 11/54 Inks based on two liquids, one liquid being the ink, the other liquid being a reaction solution, a fixer or a treatment solution for the ink

Abstract

This invention pertains to an ink set for inkjet printing, in particular to an ink set comprising at least one ink containing a self-dispersing pigment colorant and a fixer fluid containing copper salt. The invention also pertains to a method of inkjet printing with this ink set.

Claims

1. An inkjet ink set comprising:

a first ink comprising a self-dispersing pigment colorant dispersed in a first aqueous vehicle; and

a fixing fluid comprising a soluble copper salt in a second aqueous vehicle.

2. The ink set of claim 1, wherein said first ink further comprises a soluble polymer binder.

3. The ink set of claim 2 wherein the soluble polymer binder is a substantially linear, anionic polymer having a number average molecular weight in the range of 1,000 to 20,000.

4. The ink set of claim 1, wherein the first ink further comprises an effective amount of a multivalent cation.

5. The ink set of claim 1, further comprising at least four differently colored aqueous inks, at least one of the colored inks being a first ink.

6. The ink set of claim 5, further comprising at least four differently colored aqueous pigmented inks.

7. The ink set of claim 1, wherein the soluble copper in the fixing fluid is present at a level of at least 0.05 mole/L.

8. The ink set of claim 1, wherein the self-dispersing pigment in said first ink is self-dispersing carbon black pigment comprising anionic hydrophilic moieties.

9. The ink set of claim 7, wherein the anionic hydrophillic moieties on the self-dispersing carbon black pigment are primarily carboxyl groups.

10. A method of inkjet printing a substrate comprising the steps of jetting an ink set onto a substrate, the ink set comprising:

a first ink comprising a self-dispersing pigment colorant dispersed in a first aqueous vehicle; and

a fixing fluid comprising a soluble copper salt in a second aqueous vehicle.

11. The method of claim 10, wherein the fixing fluid is jetted onto the substrate before the first ink, and the area of the substrate covered by the fixing fluid is substantially covered by the first ink.

12. The method of claim 11, wherein the area fill of the fixing fluid is less than the area fill of the first ink.

13. The method of claim 12, wherein the fixing fluid is applied at an area fill of less than about 60% of the area fill of the first ink.

14. The method of claim 10, wherein said first ink further comprises a soluble polymer binder.

15. The method of claim 14, wherein the soluble polymer binder is a substantially linear, anionic polymer having a number average molecular weight in the range of 1,000 to 20,000.

16. The method of claim 10, wherein the first ink further comprises an effective amount of a multivalent cation.

17. The method of claim 10, further comprising at least four differently colored aqueous inks, at least one of the colored inks being a first ink.

18. The method of claim 10, wherein the soluble copper in the fixing fluid is present at a level of at least 0.05 mole/L.

19. The method of claim 10, wherein the self-dispersing pigment in said first ink is self-dispersing carbon black pigment comprising anionic hydrophilic moieties.

20. The method of claim 19, wherein the anionic hydrophillic moieties on the self-dispersing carbon black pigment are primarily carboxyl groups.