Dye discharge inkjet ink compositions

Patent metadata

Field	Value
Publication number	US-9725848-B2
Application number	US-201314440357-A
Country	US
Kind code	B2
Filing date	Nov 14, 2013
Priority date	Nov 14, 2012
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

A dye discharge composition exhibiting extended shelf life and/or pot life and high suitability for inkjet printing on dyed substrates, is disclosed. The composition comprises a reducing agent such as, for example, a sulfur-based reducing agent, and a chelating agent, such as a sodium salt of a polyamino carboxylic acid chelating agent. Use of the dye discharge composition in combination with a translucent colored composition and an optional opaque underbase composition, for forming an image on a dyed substrate is also disclosed. Processes for inkjet printing of an image on a dyed surface using the dye discharge composition, kits for use in such processes or an ink formulation containing same are also disclosed.

First claim

What is claimed is:

1. A dye discharge composition comprising a reducing agent, a chelating agent and a first carrier, the composition is forming a part of an ink formulation, said ink formulation further comprises a translucent colored composition, said translucent colored composition comprising a colorant, a dispersing agent and a second carrier, the composition is for forming a dye discharged area on a surface of a dyed substrate, wherein said reducing agent is a sulfur-based reducing agent, the composition is having a pH that ranges from 3 to 6.5.

2. The composition of claim 1 , wherein said first carrier is an aqueous carrier.

3. The composition of claim 1 , wherein a concentration of said sulfur-based reducing agent ranges from 300 mM to 700 mM.

4. The composition of claim 1 , wherein said chelating agent is a polyamino carboxylic acid chelating agent.

5. The composition of claim 4 , wherein a concentration of said chelating agent ranges from 300 mM to 700 mM.

6. The composition of claim 1 , wherein a molar ratio of said reducing agent to said chelating agent ranges from 0.8 to 1.2.

7. The composition of claim 1 , wherein said pH is 6.3.

8. The composition of claim 1 , further comprising a colorant which is impervious to said reducing agent.

9. The composition of claim 1 , wherein said translucent colored composition congeals or coagulates upon contact with the dye discharge composition.

10. The composition of claim 1 , wherein said ink formulation further comprises an opaque underbase composition, said opaque underbase composition comprises an opaque white colorant, a dispersing agent and a third carrier.

11. The composition of claim 10 , wherein said opaque white colorant comprises a plurality of metal oxide particles.

12. The composition of claim 10 , wherein said opaque underbase composition congeals or coagulates upon contact with the dye discharge composition.

13. The composition of claim 1 , wherein said ink formulation further comprises an immobilization composition, and wherein said translucent colored composition congeals or coagulates upon contact with said immobilization composition.

14. A kit comprising a packaging material and the dye discharge composition of claim 1 packaged therein.

15. The kit of claim 14 , wherein said reducing agent and said chelating agent are packaged individually within the kit.

16. The kit of claim 15 , wherein said first carrier is packaged together with said chelating agent.

17. The kit of claim 15 , wherein each of said reducing agent, said chelating agent and said first carrier is packaged individually within the kit.

18. The kit of claim 15 , further comprising instructions to mix said reducing agent, said chelating agent and said first carrier, so as to obtain the dye discharge composition.

19. The kit of claim 14 , wherein said reducing agent, said chelating agent and said first carrier are packaged together within the kit.

20. The kit of claim 14 , further comprising a translucent colored composition packaged individually within the kit.

21. The kit of claim 14 , further comprising an opaque underbase composition packaged individually within the kit.

22. The kit of claim 14 , further comprising an immobilization composition packaged individually within the kit.

23. A process of discharging a dye from a portion of a dyed substrate, the process comprising digitally applying, by means of inkjet printing, onto said portion of said dyed substrate the dye discharge composition of claim 1 .

24. The process of claim 23 , further comprising digitally applying substantially over said portion, by means of a plurality of inkjet printheads, a translucent colored composition, thereby forming an image on the dyed substrate.

25. The process of claim 24 , wherein said translucent colored composition congeals or coagulates upon contact with said dye discharge composition.

26. The process of claim 24 , further comprising, prior to said applying said translucent colored composition, digitally applying an opaque underbase composition substantially over said portion.

27. The process of claim 26 , wherein said opaque underbase composition congeals or coagulates upon contact with the dye discharge composition.

Assignees

• Kornit Digital Ltd

Inventors

• Mozel Jacob

Classifications

• C09D11/54

  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 · CPC title

• D06P1/627

  Sulfates · CPC title

• B41M3/006

  Patterns of chemical products used for a specific purpose, e.g. pesticides, perfumes, adhesive patterns; use of microencapsulated material; Printing on smoking articles · CPC title

• B41M3/001

  using chemical colour-formers or chemical reactions, e.g. leuco dyes or acids · CPC title

• D06P1/626

  Sulfocarboxylic acids · CPC title