Non-newtonian inkjet inks

Patent metadata

Field	Value
Publication number	US-2016355696-A1
Application number	US-201415119087-A
Country	US
Kind code	A1
Filing date	Mar 6, 2014
Priority date	Mar 6, 2014
Publication date	Dec 8, 2016
Grant date	—

Abstract

The present disclosure provides non-Newtonian inkjet inks and related methods. In one example, a non-Newtonian inkjet ink can comprise a dispersion of metal oxide particles in an amount ranging from 0.1% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; a salt in an amount of 0.05% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; and an organic solvent. Additionally, the metal oxide can form a structured network in a presence of the salt and the inkjet ink can have a dynamic viscosity ranging from 25 cps to 10,000 cps at shear rate of 5 s−1 and a dynamic viscosity ranging from 1 cps to 50 cps at a shear rate of 10,000 s−1.

First claim

What is claimed is:

1 . A non-Newtonian inkjet ink, comprising:
a metal oxide in an amount ranging from 0.1% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; a salt in an amount of 0.05% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; and an organic solvent; wherein the metal oxide forms a structured network in the presence of the salt, and wherein the inkjet ink has a dynamic viscosity ranging from 25 cps to 10,000 cps at shear rate of 5 s −1 and a dynamic viscosity ranging from 1 cps to 50 cps at a shear rate of 10,000 s −1 , measured at 25° C.

2 . The non-Newtonian inkjet ink of claim 1 , wherein the metal oxide is selected from the group consisting of aluminum oxide, silicon dioxide, zinc oxide, iron oxide, titanium dioxide, indium oxide, zirconium oxide, and mixtures thereof; and the salt includes a cation selected from the group consisting of sodium, lithium, potassium, magnesium, and calcium; and an anion selected from the group consisting of nitrate, chloride, sulfate, and acetate.

3 . The non-Newtonian inkjet ink of claim 1 , wherein the structured network is free of polymer.

4 . The non-Newtonian inkjet ink of claim 1 , wherein the organic solvent is a network participating solvent selected from the group consisting of ethylhydroxy-propanediol, glycerol, 1,5 pentanediol, ethylene glycol, triethylene glycol, and mixtures thereof; or the organic solvent is a network non-participating solvent selected from the group consisting of 2-pyrrolidinone, 1,2 pentanediol, 2-methyl-1,3-propanediol, 1,2 hexanediol, and mixtures thereof.

5 . The non-Newtonian inkjet ink of claim 1 , wherein the organic solvent comprises only network participating solvent, or a mixture of network participating solvent and network non-participating solvent.

6 . The non-Newtonian inkjet ink of claim 1 , wherein the metal oxide is present in an amount ranging from 1% to 5% by weight based on the total weight of the non-Newtonian inkjet ink, and the salt is present in an amount ranging from 0.5% to 4% by weight based on the total weight of the non-Newtonian inkjet ink.

7 . The non-Newtonian inkjet ink of claim 1 , wherein the non-Newtonian inkjet ink is an aqueous inkjet ink, and the organic solvent is present in an amount ranging from 5% to 50% by weight based on the total weight of the non-Newtonian inkjet ink.

8 . The non-Newtonian inkjet ink of claim 1 , wherein the metal oxide and the salt are present at a metal oxide to salt ratio ranging from 0.5:1 to 5:1 by weight and the metal oxide has a an average particle size ranging from 5 to 50 nm.

9 . The non-Newtonian inkjet ink of claim 1 , further comprising a colorant.

10 . The non-Newtonian inkjet ink of claim 1 , wherein the dynamic viscosity is 25 cps to 2,000 cps at shear rate of 5 s −1 and is 1 cps to 15 cps at a shear rate of shear rate of 10,000 s −1 , measured at 25° C.

11 . A method of manufacturing a non-Newtonian inkjet ink, comprising:
dispersing a metal oxide in an aqueous liquid vehicle; dissolving a salt in the aqueous liquid vehicle; and adding an organic solvent to the aqueous liquid vehicle, wherein the metal oxide, the salt and the organic solvent are present in amounts sufficient to form a structured network and provide a dynamic viscosity ranging from 25 cps to 10,000 cps at a shear rate of 5 s −1 and a dynamic viscosity ranging from 1 cps to 50 cps at a shear rate of 10,000 s −1 , measured at 25° C.

12 . The method of claim 11 , wherein the metal oxide is present in an amount ranging from 0.1% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; the salt is present in an amount of 0.05% to 10% by weight based on the total weight of the non-Newtonian inkjet ink; and the organic solvent is present in an amount ranging from 20% to 40% by weight based on the total weight of the non-Newtonian inkjet ink.

13 . The method of claim 11 , further comprising mixing a colorant into the non-Newtonian inkjet ink.

14 . The method of claim 11 , wherein the structured network is free of polymers.

15 . A method of printing a non-Newtonian inkjet ink, comprising:
shearing a non-Newtonian inkjet ink within a printhead of an inkjet printing apparatus at a shear rate of 10,000 s −1 or more to provide a dynamic viscosity ranging from 1 cps to 50 cps, wherein the non-Newtonian inkjet ink comprises water, a metal oxide, a salt, and an organic solvent, and wherein the metal oxide and the salt form a structured network; and ejecting droplets of the non-Newtonian inkjet ink.

Assignees

• Hewlett Packard Development Co Lp

Inventors

• Adamic Raymond Jr
• Kasperchik Vladek

Classifications

• C09D11/38 Primary

  characterised by non-macromolecular additives other than solvents, pigments or dyes · CPC title

• C09D11/36

  based on non-aqueous solvents · CPC title

• C09D11/322

  Pigment inks · CPC title

• B41M5/0023

  Digital printing methods characterised by the inks used (inks per se C09D11/00) · CPC title

• B41J2/01

  Ink jet · CPC title