Sulfonated polyester ink

Patent metadata

Field	Value
Publication number	US-10604668-B2
Application number	US-201816000401-A
Country	US
Kind code	B2
Filing date	Jun 5, 2018
Priority date	Jun 5, 2018
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

An aqueous ink composition including water, an optional co-solvent, a sulfonated polyester, and a polyurethane dispersion, and process of making thereof.

First claim

What is claimed is:

1. An ink composition comprising:
water;
an optional co-solvent;
a sulfonated polyester having a degree of sulfonation of from about 3.5 mole percent to about 7.5 mole percent; and
a polyurethane dispersion, and wherein the sulfonated polyester comprises a terephthalate-diol unit, a sulfonated terephthalate-diol unit and a crosslinker unit having the following structures:

wherein
each R 1 and each R 2 is independently an alkylene of from 2 to about 25 carbon atoms;
each R 3 is independently a branched or unbranched alkyl group of from 1 to 15 carbon atoms;
each R′ is independently an arylene of from about 6 to about 36 carbon atoms;
each X + is independently Na + , Li+, or K+;
n is from about 40 to about 48 mole percent;
p is from about 7.5 to about 15 mole percent; and
q is from about 0.1 to about 2.5 mole percent.

2. The ink composition of claim 1 , wherein the sulfonated polyester comprises a branched polymer.

3. The ink composition of claim 1 , wherein the sulfonated polyester comprises a linear polymer.

4. The ink composition of claim 1 , wherein the sulfonated polyester comprises a sodium sulfonated polyester.

5. The ink composition of claim 1 , wherein the sulfonated polyester comprises a polyol monomer unit selected from the group consisting of trimethylolpropane, 1,2-propanediol, diethylene glycol, and combinations thereof; and
further wherein the sulfonated polyester comprises a diacid monomer unit selected from the group consisting of terephthalic acid, sulfonated isophthalic acid, and combinations thereof.

6. The ink composition of claim 1 , wherein the sulfonated polyester is water-dissipatible.

7. The ink composition of claim 1 , wherein the sulfonated polyester is present in the ink composition in an amount of from about 10 to about 60 percent by weight based upon the total weight of the ink composition.

8. The ink composition of claim 1 , wherein the polyurethane dispersion is present in the ink composition in an amount of from about 2 to about 40 percent by weight based upon the total weight of the ink composition.

9. The ink composition of claim 1 , wherein water is present in the ink composition in an amount of from about 55 to about 85 percent by weight based upon the total weight of the ink composition.

10. The ink composition of claim 1 , wherein the co-solvent is selected from the group consisting of ethylene glycol, diethylene glycol, N-methylpyrrolidone, methoxylated glycerol, ethoxylated glycerol, sulfolane, methyl ethyl ketone, isopropanol, 2-pyrrolidinone, polyethylene glycol, and mixtures thereof.

11. The ink composition of claim 1 , wherein the co-solvent is present in the ink composition in an amount of from about 0 to about 40 percent by weight based upon the total weight of the ink composition.

12. The ink composition of claim 1 , wherein the water to co-solvent ratio is from about 100:0 to about 30:70.

13. The ink composition of claim 1 , wherein the ink composition further comprises a surfactant.

14. The ink composition of claim 1 , wherein the ink composition is substantially free of pigment.

15. The ink composition of claim 1 , wherein the ink exhibits a viscosity of from about 2 to about 100 cps at 25° C.

16. A process for digital offset printing, the process comprising:
applying an ink composition onto a re-imageable imaging member surface at an ink take up temperature, the re-imageable imaging member having dampening fluid disposed thereon;
forming an ink image; and
transferring the ink image from the re-imageable surface of the imaging member to a printable substrate at an ink transfer temperature;

wherein the ink composition comprises:
water;
an optional co-solvent;
a sulfonated polyester having a degree of sulfonation of from about 3.5 mole percent to about 7.5 mole percent; and
a polyurethane dispersion, and wherein the sulfonated polyester comprises a terephthalate-diol unit, a sulfonated terephthalate-diol unit and a crosslinker unit having the following structures:

wherein
each R 1 and each R 2 is independently an alkylene of from 2 to about 25 carbon atoms;
each R 3 is independently a branched or unbranched alkyl group of from 1 to 15 carbon atoms;
each R′ is independently an arylene of from about 6 to about 36 carbon atoms;
each X + is independently Na + , Li+, or K+;
n is from about 40 to about 48 mole percent;
p is from about 7.5 to about 15 mole percent; and
q is from about 0.1 to about 2.5 mole percent.

17. The process of claim 16 , wherein the ink composition is substantially free of pigment.

Assignees

• Xerox Corp

Inventors

• Chopra Naveen
• Claridge Rob
• Abraham Biby Esther
• Moorlag Carolyn
• Lee Jonathan Siu-Chung
• Sacripante Guerino

Classifications

• C09D11/104 Primary

  Polyesters · CPC title

• C08G63/688 Primary

  containing sulfur · CPC title

• B41M5/382

  Contact thermal transfer or sublimation processes (sublistatic printing using a pre-formed image B41M5/035; ink-, dye- or pigment-receptive coatings B41M5/52) · CPC title

• C09D11/102

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

• B41M5/025

  by transferring ink from the master sheet · CPC title