Ink, ink set, ink cartridge, recording unit, image recording apparatus and image recording method

• US 6,280,513 B1
• Filed: 03/17/1999
• Issued: 08/28/2001
• Est. Priority Date: 03/20/1998
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yakushigawa, Yuko, Sanada, Mikio, Osumi, Koichi, Mishina, Shinya, Takizawa, Yoshihisa, Teraoka, Hisashi, Hattori, Yoshifumi
• Primary Examiner(s): KLEMANSKI, HELENE G
• Application Number:
  US09/271,248
• Time in Patent Office: 895 Days
• Field of Search: 106/31.6, 106/31.75, 106/31.86
• US Class Current: 106/31.6
• CPC Class Codes: B41J 2/01 Ink jet
• CPC Class Codes: C09D 11/38 characterised by non-macromolecular additives other than solvents, pigments or dyes
• CPC Class Codes: C09D 11/40 Ink-sets specially adapted for multi-colour inkjet printing

Abstract

Provided is a black ink capable of mitigating the dependency on image quality of recording media and giving a high quality image stably, which comprises at least one salt selected from the group consisting of (M1)₂SO₄, CH₃COO(M1), Ph_COO(M1), (M1)NO₃, (M1)Cl, (M1)Br, (M1)I, (M1)₂SO₃ and (M1)₂CO₃, where M1 is an alkali metal, ammonium or organo-ammonium and Ph is a phenyl group, and a self dispersible carbon black.

Claims

1. An ink for forming a print image having an optical density on a recording medium by an ink-jet method, wherein the ink comprises at least one salt selected from the group consisting of (M1)₂SO₄, CH₃COO(M1), Ph—

COO(M1), (M1)NO₃, (M1)Cl, (M1)Br, (M1)I, (M1)₂SO₃, and (M1)₂CO₃, wherein M1 is an alkali metal, ammonium or organic ammonium and Ph is a phenyl group, and a self dispersing carbon black; and

wherein the concentration of the carbon black is such that the optical density of the image cannot be obtained when no salt is contained in the ink.

2. The ink according to claim 1, wherein the salt is contained in an amount of from 0.05 to 10% by weight relative to the whole weight of ink.

3. The ink according to claim 2, wherein the salt is contained in an amount of from 0.1 to 5% by weight relative to the whole weight of ink.

4. The ink according to claim 1, wherein the carbon black has at least one hydrophilic group bonded directly or via another atomic group to the surface.

5. The ink according to claim 4, wherein the hydrophilic group is at least one selected from the group consisting of —

COO(M2), —

SO₃(M2)₂, —

PO₃H(M2), —

NH₃⁺, —

NR₃⁺, —

SO₂N⁺H₄, —

SO₂N⁺H_sCOR,

where M2 in the formulae is a hydrogen atom, an alkali metal, ammonium or organo-ammonium and R is an alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted phenyl group or substituted or unsubstituted naphthyl group.

6. The ink according to claim 4, wherein the another atomic group is an alkylene group having 1 to 12 carbon atoms, a substituted or unsubstituted phenylene group or substituted or unsubstituted naphthylene group.

7. The ink according to claim 4, wherein the hydrophilic group is at least one selected from the group consisting of —

COO(M2), —

SO₃(M2)₂ and —

PO₃H(M2)₂ where M2 is the same as M1.

8. The ink according to claim 1, wherein the ink further comprises a stabilizer.

9. The ink according to claim 8, wherein the stabilizer is a surfactant.

10. The ink according to claim 9, wherein the surfactant is an ionic surfactant.

11. The ink according to claim 8, wherein the stabilizer is dodecylbenzenesulfonate.

12. The ink according to claim 8, wherein the stabilizer is contained in an amount of from 0.02 to 0.1% by weight.

13. The ink according to claim 1, wherein the ink has a pH of from 9 to 12.

14. The ink according to claim 13, wherein the ink has a pH of from 9 to 11.

15. The ink according to claim 1, wherein the ink further comprises an antioxidant.

16. The ink according to claim 15, wherein the antioxidant is contained in an amount of from 0.02 to 10% by weight.

17. Ink as set forth in claim 15, wherein the antioxidant is at least one selected from the group consisting of sulfites, ascorbates and hydrogensulfite.

18. The ink according to claim 1, wherein the ink further comprises a water-soluble polymer compound.

19. The ink according to claim 18, wherein the water-soluble polymer compound has a weight average molecular weight of from 1,000 to 5000.

20. The ink according to claim 18, wherein the water-soluble polymer compound is contained in an amount of from 0.02 to 2% by weight relative to the whole weight of ink.

21. The ink according to claim 18, wherein the water-soluble polymer compound is contained in an amount of from 0.1 to 1% by weight relative to the whole weight of ink.

22. The ink according to claim 1, wherein Ka value measured by the Bristow method is not more than 1.5.

23. The ink according to claim 22, wherein the Ka value measured by the Bristow method is within a range of from 0.2 to 1.5.

24. An ink set comprising a combination of aqueous ink comprising at least one coloring material selected from coloring materials for cyan, for magenta, for yellow, for red, for green and for blue and the ink according to claim 1.

25. The ink set according to claim 24, wherein the coloring material is an acid dye or a direct dye.

26. The ink set according to claim 24, wherein the coloring material is a pigment.

27. An ink cartridge comprising an ink tank for storing the ink therein according to claim 1.

28. A recording unit comprising an ink storing section for storing the ink according to claim 1 and a head section for ejecting the ink.

29. An image recording apparatus comprising:

an ink cartridge having the ink tank for storing ink according to claim 1, a recording head for ejecting the ink and supply means for supplying the ink to the recording head from the ink cartridge.

30. An image recording apparatus comprising:

an ink storing section for storing the ink according to claim 1, and a recording unit equipped with the section for ejecting the ink.

31. An image recording apparatus comprising:

an ink storing section for storing aqueous ink comprising at least one coloring material selected from coloring materials for cyan, for magenta, for yellow, for red, for green and for blue, an ink storing section for storing the ink according to claim 1 and head sections for respectively ejecting the ink stored in individual ink storing sections.

32. An image recording apparatus comprising:

an ink cartridge equipped with an ink storing section for storing aqueous ink comprising at least one coloring material selected from coloring materials for cyan, for magenta, for yellow, for red, for green and for blue,

an ink cartridge equipped with an ink storing section for storing the ink according to claim 1, head sections for respectively ejecting the ink stored in individual ink storing sections, and

supply means for supplying individual types of the ink from the respective ink cartridges to the respective head sections.

33. An image recording method comprising the steps of ejecting the ink according to claim 1, toward a recording medium surface and depositing the ink on the recording medium surface for the recording of an image.

34. The image recording method according to claim 33, wherein energy for ejecting the ink is thermal energy.

35. The image recording method according to claim 33, wherein energy for ejecting the ink is mechanical energy.

36. A color image forming method comprising the steps of:

ejecting a first aqueous ink comprising at least one coloring material selected from coloring materials for cyan, for magenta, for yellow, for red, for green and for blue toward a surface of a recording medium and depositing the ink to the surface; and

ejecting a second ink according to any one of claim 1 toward a surface of a recording medium and depositing the ink to the surface.

37. The method according to claim 33 or 36, wherein the recording medium is plain paper.