White inks

Patent metadata

Field	Value
Publication number	US-10167400-B2
Application number	US-201515544301-A
Country	US
Kind code	B2
Filing date	Apr 27, 2015
Priority date	Apr 27, 2015
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

The present disclosure provides a white ink including an aqueous ink vehicle, from 5 wt % to 50 wt % of a white metal oxide pigment having an average particulate size from 100 nm to 2,000 nm, from 0.02 wt % to 2 wt % of an anionic low molecular weight polymer having a weight average molecular weight of 3,000 Mw to 50,000 Mw and an acid number higher than 100 mg KOH/g based on dry polymer weight, and from 2 wt % to 30 wt % of latex particulates having a glass transition temperature from 0 C to 130 C. Furthermore, the white metal oxide pigment is dispersed by a non-ionic or predominantly non-ionic dispersant having an acid number not higher than 100 mg KOH/g based on dry polymer weight.

First claim

What is claimed is:

1. A white ink, comprising:
an aqueous ink vehicle;
from 5 wt % to 50 wt % of a white metal oxide pigment having an average particulate size from 100 nm to 2,000 nm, and being dispersed by a non-ionic or predominantly non-ionic dispersant having an acid number not higher than 100 mg KOH/g based on dry polymer weight;
from 0.02 wt % to 2 wt % of an anionic low molecular weight polymer having a weight average molecular weight of 3,000 Mw to 50,000 Mw and an acid number higher than 100 mg KOH/g based on dry polymer weight; and
from 2 wt % to 30 wt % of latex particulates having a glass transition temperature from 0° C. to 130° C.

2. The white ink of claim 1 , wherein the white metal oxide pigment includes titanium dioxide particulates, zinc oxide particulates, zirconium oxide particulates, or combinations thereof.

3. The white ink of claim 1 , wherein the white metal oxide pigment has an average particulate size from 150 nm to 500 nm.

4. The white ink of claim 1 , wherein the anionic low molecular weight polymer is present at from 0.05 wt % to 0.9 wt %.

5. The white ink of claim 1 , wherein the anionic low molecular weight polymer has a weight average molecular weight of 4,000 Mw to 10,000 Mw.

6. The white ink of claim 1 , wherein the white metal oxide pigment and latex particulates are present in the white ink at a weight ratio from 6:1 to 1:3.

7. The white ink of claim 1 , wherein the latex particulates have a glass transition temperature from 40° C. to 130° C.

8. The white ink of claim 1 , wherein the non-ionic dispersant has an acid number of 30 mg KOH/g or less.

9. The white ink of claim 1 , wherein the non-ionic or predominantly non-ionic dispersant is a hydrophilic alkoxysilane dispersing agent, a water-hydrolysable silane coupling agents with oligomer length range polyether chains, or a low-to-midrange branched co-polymer of comb-type structure with polyether pendant chains and acidic anchor groups attached to its backbone.

10. The white ink of claim 1 , wherein the white ink is a thermal inkjet ink.

11. A method of making a white ink, comprising:
milling a white metal oxide pigment in a water-based carrier with a non-ionic or predominantly non-ionic dispersing agent to form a white metal oxide pigment dispersion, wherein the non-ionic or predominantly non-ionic dispersant is defined by having an acid number not higher than 100 mg KOH/g based on dry polymer weight; and
admixing with the white metal oxide pigment dispersion: water, organic co-solvent, anionic low molecular weight polymer having a weight average molecular weight of 3,000 Mw to 50,000 Mw and an acid number higher than 100 mg KOH/g based on dry polymer weight, and
latex particulates, to form a white ink.

12. The method of claim 11 , wherein the white ink, comprises:
from 5 wt % to 50 wt % of the white metal oxide pigment having an average particulate size from 100 nm to 2,000 nm;
from 0.02 wt % to 2 wt % of the anionic low molecular weight polymer; and
from 2 wt % to 30 wt % of latex particulates having a glass transition temperature from 0° C. to 130° C.

13. A white thermal inkjet ink, comprising:
an aqueous inkjet ink vehicle;
from 10 wt % to 35 wt % of a TiO 2 pigment having an average particulate size from 150 nm to 500 nm, wherein the TiO 2 pigment is dispersed with a non-ionic or predominantly non-ionic dispersant having an acid number not higher than 30 mg KOH/g based on dry polymer weight; and
from 0.02 wt % to 2 wt % of an anionic low molecular weight polymer having a weight average molecular weight of 3,000 Mw to 50,000 Mw and an acid number higher than 150 mg KOH/g based on dry polymer weight.

14. The white thermal inkjet ink of claim 13 , further comprising from 2 wt % to 30 wt % of latex particulates having a glass transition temperature from 0° C. to 130° C.

15. The white thermal inkjet ink of claim 13 , wherein the anionic low molecular weight polymer is present at from 0.05 wt % to 0.9 wt %, and has a weight average molecular weight of 4,000 Mw to 10,000 Mw.

16. The method of claim 11 , wherein the white metal oxide pigment includes titanium dioxide particulates, zinc oxide particulates, zirconium oxide particulates, or combinations thereof.

17. The method of claim 11 , wherein the white metal oxide pigment includes titanium dioxide particulates.

18. The method of claim 11 , wherein the white metal oxide pigment has an average particulate size from 150 nm to 500 nm.

19. The method of claim 12 , wherein the anionic low molecular weight polymer is present in the white ink at from 0.05 wt % to 0.9 wt %, and has a weight average molecular weight of 4,000 Mw to 10,000 Mw.

20. The white thermal inkjet ink of claim 13 , wherein the white metal oxide pigment and latex particulates are present in the white ink at a weight ratio from 6:1 to 1:3.

Assignees

• Hewlett Packard Development Co
• Hewlett Packard Development Co

Inventors

• Bruinsma Paul Joseph
• Kasperchik Vladek
• Butler Thomas W

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

• C09D11/326

  characterised by the pigment dispersant · CPC title

• C09D17/001

  in aqueous medium (C09D17/003, C09D17/004 take precedence) · CPC title

• C09D11/102

  containing macromolecular compounds obtained by reactions other than those only involving unsaturated carbon-to-carbon bonds · CPC title

• C09D11/322 Primary

  Pigment inks · CPC title