Ink dispersion

• US 8,764,894 B2
• Filed: 10/29/2010
• Issued: 07/01/2014
• Est. Priority Date: 10/29/2010
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Ng, Hou T., Bhattacharyya, Manoj K., Tom, Howard S.
• Primary Examiner(s): Faison, Veronica F
• Application Number:
  US12/916,141
• Publication Number:
  US 20120103542A1
• Time in Patent Office: 1,341 Days
• Field of Search: 106/31.59, 106/31.89, 106/31.58, 106/31.86
• US Class Current: 106/31.59
• CPC Class Codes: C09D 11/32 characterised by colouring agents
• 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
• 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
• CPC Class Codes: D21C 5/02 Working-up waste paper mechanical part D21B1/08, D21B1/32
• CPC Class Codes: Y02W 30/64 Paper recycling

Abstract

An ink dispersion includes an ink vehicle and a colorant dispersed in the ink vehicle. The ink vehicle includes a non-ionic surfactant and a solvent. The non-ionic surfactant has an HLB value ranges from about 5 to about 16, and is chosen from: i) a material represented by one of the formulas R₁—O—(OR₂)_n—H, R₁—(OR₂)_n—OH or R₁—C₆H₄—(OR₂)_n—OH, wherein: R₁ is chosen from a) a linear or cyclic alkyl group including from 3 to 20 carbon atoms, or b) a substituted or non-substituted alkyl group including from 6 to 18 carbon atoms, R₂ is chosen from CH₂CH₂ or CH₂CH₂CH₂, and n is an integer chosen from 2 to 100; or ii) a diester having at least one ethylene oxide repeating unit; or iii) an octylphenol having at least one ethylene oxide repeating unit.

Claims

1. An ink dispersion, consisting of:

an ink vehicle, consisting of;

a non-ionic surfactant having an HLB value ranging from about 5 to about 16, the non-ionic surfactant being selected from the group consisting of polyethylene glycol hexadecyl ether (C₁₆H₃₃—

(OCH₂CH₂)₂OH), polyethylene glycol stearate CH₃(CH₂)₁₆COO(CH₂CH₂O)₈H, and combinations thereof;

water as a solvent; and

optionally an additive selected from the group consisting of a biocide, a buffering agent, a chelating agent, and combinations thereof; and

a colorant dispersed in the ink vehicle;

wherein the non-ionic surfactant is a displector, and wherein the displector, when combined with a frother from a waste paper recycling system, enables deinking of the colorant from a medium on which the colorant is established.

2. The ink dispersion as defined in claim 1 wherein the biocide is present in an amount ranging from about 0.01 wt % to about 0.2 wt % of a total weight percent of the ink dispersion.

3. The ink dispersion as defined in claim 1 wherein the colorant is chosen from at least one of a pigment or a dye, and wherein the colorant is present in an amount ranging from about 3 wt % to about 6 wt % of a total weight percent of the ink dispersion.

4. The ink dispersion as defined in claim 3 wherein the pigment is chosen from a self-dispersed pigment, a polymer-attached pigment, a surfactant-absorbed pigment, a polymer-coated pigment, or combinations thereof.

5. The ink dispersion as defined in claim 3 wherein the dye is chosen from a water-soluble dye, a pigment-coated dye, or combinations thereof.

6. An ink system, comprising:

a printing system, including;

at least one ink chamber for storing an ink dispersion, the ink dispersion consisting of;

an ink vehicle, consisting of;

a non-ionic surfactant having an HLB value ranging from about 5 to about 16, the non-ionic surfactant being selected from the group consisting of polyethylene glycol hexadecyl ether (C₁₆H₃₃—

(OCH₂CH₂)₂OH), polyethylene glycol stearate CH₃(CH₂)₁₆COO(CH₂CH₂O)₈H, and combinations thereof;

water as a solvent; and

optionally an additive selected from the group consisting of a biocide, a buffering agent, a chelating agent, and combinations thereof; and

a colorant dispersed in the ink vehicle;

at least one fluid ejector for depositing, onto a medium, a portion of the ink dispersion retrieved from the at least one ink chamber; and

the medium upon which the portion of the ink dispersion is to be deposited;

wherein the non-ionic surfactant is a displector, and wherein the displector, when combined with a frother from a waste paper recycling system, enables deinking of the colorant from the medium.

7. The ink system as defined in claim 6 wherein the printing system is a digital printing system that uses thermal inkjet printing or piezoelectric inkjet printing.

8. The ink system as defined in claim 6 wherein the HLB value of the non-ionic surfactant ranges from about 8 to about 13.

9. A method of deinking a printed medium, comprising:

converting the printed medium into a slurry, the slurry including pulp and an ink that was printed on the medium, wherein the ink consists of;

an ink vehicle, consisting of;

a non-ionic surfactant being a deinking component and having an HLB value ranging from about 5 to about 16, the non-ionic surfactant being selected from the group consisting of polyethylene glycol hexadecyl ether (C₁₆H₃₃—

(OCH₂CH₂)₂OH), polyethylene glycol stearate CH₃(CH₂)₁₆COO(CH₂CH₂O)₈H, and combinations thereof;

water as a solvent; and

optionally an additive selected from the group consisting of a biocide, a buffering agent, a chelating agent, and combinations thereof; and

a colorant dispersed in the ink vehicle;

wherein the non-ionic surfactant is a displector, and wherein the displector, when combined with a frother from a waste paper recycling system, enables deinking of the colorant from a medium on which the colorant is established; and

separating the ink from the slurry by interacting the deinking component of the ink with the colorant that is present in the ink.

10. The method as defined in claim 9 wherein the printed medium includes digital printed papers.

11. The method as defined in claim 9, further comprising removing the separated ink from the slurry by incorporating a frother into the slurry.

12. An ink dispersion, consisting of:

an ink vehicle, consisting of;

polyethylene glycol hexadecyl ether (C₁₆H₃₃—

(OCH₂CH₂)₂OH) as a non-ionic surfactant having an HLB value of 5;

a solvent; and

optionally an additive selected from the group consisting of a biocide, a buffering agent, a chelating agent, a latex, a co-solvent, and combinations thereof; and

a colorant dispersed in the ink vehicle;

wherein the non-ionic surfactant is a displector, and wherein the displector, when combined with a frother from a waste paper recycling system, enables deinking of the colorant from a medium on which the colorant is established;

and wherein the ink dispersion is a water-based dispersion.