Cationic modified self-dispersing pigment dispersions

Patent metadata

Field	Value
Publication number	US-10351708-B2
Application number	US-201615570409-A
Country	US
Kind code	B2
Filing date	Apr 27, 2016
Priority date	Apr 30, 2015
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

This invention pertains to self-dispersing pigment dispersions. The self-dispersing pigments are modified with a multivalent cation and an anionic polymer.

First claim

What is claimed is:

1. An aqueous pigment dispersion comprising:
a self-dispersing pigment having at least one type of hydrophilic functional group bonded onto a surface of the self-dispersing pigment, said at least one type of hydrophilic functional group comprising a carboxyl group;
a multivalent cation selected from the group consisting of Mg 2+ , Ca 2+ , Cu 2+ , Al 3+ , Fe 3+ , and mixtures thereof, wherein said multivalent cation is adsorbed onto said self-dispersing pigment via ionic bonds between the multivalent cation and surface acid group on the self-dispersing pigment displacing monovalent cation(s) associating with the carboxyl group on the surface of the self-dispersing pigment, the displaced monovalent cation(s) are removed from the pigment dispersion; and
an anionic polymeric binder.

2. The pigment dispersion of claim 1 , wherein said multivalent cation is present at a level of at least 2 ppm.

3. The pigment dispersion of claim 1 , wherein said multivalent cation is Mg 2+ .

4. The pigment dispersion of claim 1 , wherein said multivalent cation is Cu 2+ .

5. The pigment dispersion of claim 1 , wherein said multivalent cation is Ca 2+ .

6. The pigment dispersion of claim 1 , wherein said multivalent cation is Al 3+ .

7. The pigment dispersion of claim 1 , wherein said anionic polymeric binder is selected from the group consisting of polyurethane, waterborne acrylic copolymer, waterborne polyester, and mixtures thereof.

8. The pigment dispersion of claim 7 , wherein said polyurethane is amphoteric.

9. The pigment dispersion of claim 7 , wherein said polyurethane is an amphoteric polyester.

10. The pigment dispersion of claim 7 , wherein said waterborne acrylic copolymer is a random polymer.

11. The pigment dispersion of claim 7 , wherein said waterborne acrylic copolymer is a block polymer.

12. The pigment dispersion of claim 7 , wherein said waterborne acrylic copolymer is a graft polymer.

Assignees

• Du Pont

Inventors

• Wolfe Michael Stephen
• Berge Charles T
• Tam Loretta L
• Kirkpatrick Cullen

Classifications

• C09B67/0088 Primary

  cationic dispersing agents · CPC title

• C09D11/326

  characterised by the pigment dispersant · CPC title

• C09D17/005

  Carbon black · CPC title

• C09D17/001

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

• C09B67/009

  polymeric dispersing agent · CPC title