White pigment dispersions

Patent metadata

Field	Value
Publication number	US-9878920-B2
Application number	US-201314908009-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Sep 27, 2013
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A white pigment dispersion includes 10 to 60 wt % of low effective density TiO2, 1 to 40 wt % of a latex, and the balance a dispersing medium. Inks using the low effective density TiO2 and methods for preparing the low effective density TiO2 are also disclosed.

First claim

What is claimed is:

1. A white pigment dispersion, comprising:
10 to 60 wt % of porous, low effective density TiO 2 ;
1 to 40 wt % of a latex; and
a balance of a dispersing medium;
wherein the effective density of porous, low effective density TiO 2 is less than 4.

2. The white pigment dispersion of claim 1 wherein the effective density of the porous, low effective density TiO 2 is within a range of about 2.5 to 3.8.

3. The white pigment dispersion of claim 1 wherein the latex is selected from the group consisting of styrene-acrylic latex, polyurethane latex, polyvinyl acetate, acrylonitrile butadiene styrene (ABS) latex, acrylic polymers, and poly(ethylene acrylic acid).

4. The white pigment dispersion of claim 1 wherein the dispersing medium is selected from the group consisting of water and an alcohol having from 2 to 6 carbon atoms and mixtures thereof.

5. An ink including a white pigment dispersion, including:
10 to 60 wt % of a white pigment dispersion, the white pigment dispersion comprising:
10 to 60 wt % of porous, low effective density TiO 2 ,
1 to 40 wt % of a latex, and
a balance of a dispersing medium;
wherein the effective density of the porous, low effective density TiO 2 is less than 4;

1 to 10 wt % of co-solvent; and
up to 10 wt % of a component selected from the group consisting of surfactants, biocides, fungicides, sequestering agents, buffering agents and anti-kogation agents, and mixtures thereof.

6. The ink of claim 5 wherein the porous, low effective density TiO 2 has a particle size within a range of about 100 to 300 nm.

7. A method for manufacturing porous, low effective density TiO 2 , comprising:
providing a template having a surface;
coating the template surface with a titanium-containing compound that can be reduced to TiO 2 at high temperature; and
removing the template, thereby forming porous TiO 2 particles;
wherein the effective density of the porous TiO 2 particles is less than 4;
and wherein the porous, low effective density TiO 2 particles are included in a white pigment dispersion, comprising:
10 to 60 wt. % of porous, low effective density TiO 2 ;
1 to 40 wt. % of a latex; and
a balance of a dispersing medium.

8. The method of claim 7 wherein the titanium-containing compound is selected from the group consisting of titanium oxysulfate, titanium diisopropoxide bis(acetylacetonate), titanium(IV) ethoxide, and tetrakis(diethylamido) titanium(IV).

9. The method of claim 7 , comprising:
forming the template comprising a polymer emulsion with carboxylate groups;
coating the template surface with the titanium-containing compound; and
removing the polymer template, thereby forming the porous TiO 2 particles.

10. The method of claim 7 comprising:
providing a bubble nucleating agent;
combining the titanium-containing compound with the bubble nucleation agent and stirring to form the template, which comprises oxygen bubbles, coated with TiO(OH) 2 ;
removing water; and
removing the oxygen bubble template, thereby forming the porous TiO 2 particles.

11. The method of claim 10 wherein the bubble nucleating agent comprises a mixture of hydrogen peroxide, urea, and water.

12. The method of claim 7 wherein the effective density of the porous TiO 2 particles is within a range of about 2.5 to 3.8.

13. The method of claim 7 wherein the template is removed by calcining at a temperature of at least 500° C. for a period of time of at least 5 hours.

14. The white pigment dispersion of claim 2 wherein the porous, low effective density TiO 2 has a porosity of about 50%.

Assignees

• Hewlett Packard Development Co Lp

Inventors

• Zhao Yan
• Tom Howard S
• Ng Hou T

Classifications

• C09D5/028

  Pigments; Filters · CPC title

• C01P2004/62

  Submicrometer sized, i.e. from 0.1-1 micrometer · CPC title

• C09D11/023

  Emulsion inks · CPC title

• C01G23/0532

  by hydrolysing sulfate-containing salts · CPC title

• C09C1/00

  Treatment of specific inorganic materials other than fibrous fillers (tenebrescent materials C09K9/00; luminescent materials C09K11/00); Preparation of carbon black · CPC title