Dispersed white inks

Patent metadata

Field	Value
Publication number	US-9714352-B2
Application number	US-201415118023-A
Country	US
Kind code	B2
Filing date	Mar 31, 2014
Priority date	Mar 31, 2014
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A dispersed white ink contains TiO 2 , wherein the TiO 2 includes particles contained in a thermoplastic polymer resin matrix and wherein the particles have a maximum interparticle distance of less than 1.0 μm and exhibit a statistical variance of less than 0.02. A process for manufacturing the dispersed white ink is also provided.

First claim

What is claimed is:

1. A dispersed white ink containing TiO 2 , wherein the TiO 2 comprises particles contained in a thermoplastic polymer resin matrix and wherein the particles have a maximum interparticle distance of less than 1.0 μm and exhibiting a statistical variance of less than 0.02.

2. The dispersed white ink of claim 1 , wherein the thermal polymer resin matrix comprises a thermoplastic composition that is colorless and translucent to at least visible radiation.

3. The dispersed white ink of claim 1 , wherein the ink has a non-volatile solids content within a range of 1 to 10 wt %.

4. The dispersed white ink of claim 1 , wherein the ink has a composition:

thermoplastic resin
11 to 89
wt %;

TiO 2
10 to 65
wt %;

secondary pigment
0 to 3
wt %;

aluminum stearate
0 to 1
wt %;

other additives
1 to 5
wt %;

silicone oil
0 to 5
wt %;

charge director
0.1 to 10
wt %; and

isoparaffinic liquid
balance.

5. A process for manufacturing a dispersed white ink containing TiO 2 pigment, the process including:
integrating components for the white ink;
reducing particle size and dispersing particles in an ink carrier fluid to form a semi-solid mixture; and
grinding the semi-solid mixture to form the dispersed white ink.

6. The process of claim 5 , wherein the process further includes forming pellets of solids containing the integrated component after integrating the components for the white ink.

7. The process of claim 5 , wherein components for the white ink include solid materials comprising about 20 to 100 wt % of the total composition and liquid materials comprising 0 to about 80 wt % of the total composition.

8. The process of claim 7 , wherein the components include the TiO 2 pigment, a thermoplastic polymer resin, and the ink carrier fluid.

9. The process of claim 8 , wherein the components include:

thermoplastic resin
11 to 89
wt %;

TiO 2
10 to 65
wt %;

secondary pigment
0 to 3
wt %;

aluminum stearate
0 to 1
wt %;

other additives
1 to 5
wt %;

silicone oil
0 to 5
wt %;

charge director
0.1 to 10
wt %; and

isoparaffinic liquid
balance.

10. The process of claim 5 , wherein integrating the components is performed with an extruder two or more mixing zones, a first zone for dispersing TiO 2 pigment into a melted thermoplastic extrusion resin to form a polymer-pigment combination and a second zone for mixing the polymer-pigment composition with the ink carrier fluid.

11. The process of claim 5 , wherein reducing the particle size is performed by milling, grinding, or a combination of milling and grinding.

12. The process of claim 5 , wherein dispersing the particles in the ink carrier fluid by homogenizing, microfluidizing, or a combination of homogenizing and microfluidizing.

13. The process of claim 5 , wherein grinding the semi-solid mixture is performed in a bead mill or attritor with beads having a size ranging from 2 to 10 mm at a rate of 100 to 1000 rpm for 5 to 50 hours to form the dispersed white ink.

14. The process of claim 13 , wherein the dispersed white ink is diluted with additional ink carrier fluid to a concentration of about 1 to 10 wt % non-volatile solids.

15. The process of claim 5 , wherein the ink carrier fluid comprises an isoparaffinic liquid.

Assignees

• Hewlett Packard Development Co Lp

Inventors

• Chun Doris
• Ng Hou T
• Teishev Albert

Classifications

• C09D11/10

  based on artificial resins · CPC title

• C09D11/037 Primary

  characterised by the pigment · CPC title

• C09D11/108

  Hydrocarbon resins · CPC title