# US 8,784,550 B2 · Oxide pigment dispersion for inkjet ink

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,784,550 B2
- Document ID: US8784550B2
- Status: Granted
- Kind: B2
- Application number: 13/819,962
- Filed: 2010-10-22
- Published: 2013-06-27
- Granted: 2014-07-22
- Earliest claimed: 2010-10-22
- Assignees: Hewlett-Packard Development Company, L.P.
- Applicants: Vladek Kasperchik
- Inventors: Vladek Kasperchik
- Web page: https://patentgrep.com/patent/US8784550B2

## CPC

- C09C 3/12: Treatment with organosilicon compounds {(C09C3/006 takes precedence)}
- B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites
- C09C 1/3684: {Treatment with organo-silicon compounds}
- C09D 11/322: Pigment inks
- C09D 11/326: characterised by the pigment dispersant
- C01P 2004/62: Submicrometer sized, i.e. from 0.1-1 micrometer
- C01P 2004/64: Nanometer sized, i.e. from 1-100 nanometer
- C09C: TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES (treatment of materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone C04B14/00, C04B18/00, C04B20/00); PREPARATION OF CARBON BLACK {; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS}
- B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS

## Abstract

An oxide pigment dispersion comprised of nano-sized particles of inorganic oxide and a reactive dispersant, and an inkjet ink based on this dispersion.

## Claims

### Claim 1

An oxide pigment dispersion, consisting of:
a. inorganic oxide particles having a particle size of less than about 150 nm;
b. a polyether alkoxysilane reactive dispersant represented by the following general Formula (I):
wherein R1, R2 and R3 are hydroxyl, linear or branched alkoxy groups that undergo hydrolysis in water to form a reactive silanol group that attaches to a hydroxyl group on a surface of the inorganic oxide particles; PE is a polyether oligomer chain segment of the structural formula: [(CH2)n—CHR—O—]m, wherein n is an integer ranging from 0 to 3, wherein m is an integer superior or equal to 2, and wherein R is H or a chain alkyl group; and wherein R4 is hydrogen, or a linear or branched alkyl group; and
c. the water.

### Claim 2 (depends on 1)

The oxide pigment dispersion of claim 1, wherein the polyether alkoxysilane reactive dispersant of Formula (I), at least one of R1, R2 and R3 group is a linear or branched alkoxy group.

### Claim 3 (depends on 1)

The oxide pigment dispersion of claim 1 wherein the inorganic oxide particles are made of metal oxide or semi-metal oxide.

### Claim 4

An oxide pigment dispersion, consisting of:
a. inorganic oxide particles having a particle size less than about 150 nm and
b. a polyether alkoxysilane reactive dispersant represented by the following general Formula (II):
wherein R′, R″ and R′″ are linear or branched alkyl groups that undergo hydrolysis in water to form a reactive silanol group that attaches to a hydroxyl group on a surface of the inorganic oxide particles; PE is a polyether oligomer chain segment of the structural formula: [(CH2)n—CHR—O—]m, wherein n is an integer ranging from 0 to 3, wherein m is an integer superior or equal to 2, and wherein R is H or a chain alkyl group having from 1 to 3 carbon atoms; and R4 is H or a linear or branched alkyl group having from 1 to 5 carbon atoms; and
c. the water.

### Claim 5 (depends on 4)

The oxide pigment dispersion of claim 4, wherein R′, R″ and R′″ are linear or branched alkyl groups having from 1 to 3 carbon atoms in chain length.

### Claim 6 (depends on 1)

The oxide pigment dispersion of claim 1, wherein m is an integer from 2 to 30.

### Claim 7 (depends on 1)

The oxide pigment dispersion of claim 1, wherein R4 is CH3 or C2H5.

### Claim 8 (depends on 1)

The oxide pigment dispersion of claim 1, wherein PE is a polyethylene glycol (PEG) chain segment (—CH2CH2—O—)m, or a polypropylene glycol (PPG) chain segment (—CH2—CH2—CH2—O—)m, or a mixture thereof.

### Claim 9 (depends on 1)

The oxide pigment dispersion of claim 1, wherein PE is a PEG chain (—CH2CH2—O—)m and m is an integer from 2 to 30.

### Claim 10 (depends on 4)

The oxide pigment dispersion of claim 4, wherein the inorganic oxide particles are made of metal oxide or semi-metal oxide.

### Claim 11 (depends on 1)

The oxide pigment dispersion of claim 1, wherein the inorganic oxide particles have the particle size in the range of about 5 nm to about 100 nm.

### Claim 12 (depends on 1)

An ink for inkjet printing, the ink comprising:
the oxide pigment dispersion of claim 1;
an aqueous carrier including water and at least one water soluble organic co-solvent; and
a surfactant;
wherein an amount of the at least one water soluble organic co-solvent in the ink is greater than 0% and up to 50%, an amount of the surfactant in the ink is greater than 0% and up to 5%, an amount of metal oxide particles in the ink is the range of greater than 0% and up to 20% by weight, and a balance of the ink is the water.

### Claim 13 (depends on 4)

An ink for inkjet printing, the ink comprising:
the oxide pigment dispersion of claim 4;
an aqueous carrier including water and at least one water soluble organic co-solvent; and
a surfactant;
wherein an amount of the at least one water soluble organic co-solvent in the ink is greater than 0% and up to 50%, an amount of the surfactant in the ink is greater than 0% and up to 5%, an amount of metal oxide particles in the ink is the range of greater than 0% and up to 35% by weight, and a balance of the ink is the water.

### Claim 14

A method for making an oxide pigment dispersion, said method comprising:
forming a mixture consisting of an inorganic oxide pigment, water, and a polyether alkoxysilane reactive dispersant to form a starting aqueous dispersion, said polyether alkoxysilane reactive dispersant having the following general Formula II:
wherein
a) R′, R″ and R′″ are linear or branched alkyl groups;
b) PE is a polyether oligomer chain segment of the structural formula: [(CH2)n—CHR—O—]m, wherein n is an integer ranging from 0 to 3, wherein m is an integer superior or equal to 2, and wherein R is H or a chain alkyl group having from 1 to 3 carbon atoms;
c) R4 is H or a linear or branched alkyl group having from 1-5 carbon atoms; and
milling the aqueous starting dispersion to reduce the particle size of the inorganic oxide pigment;
whereby the polyether alkoxysilane reactive dispersant dissolve in the water and undergo hydrolysis to form a hydrolyzed polyether alkoxysilane reactive dispersant having a silanol group that reacts with a hydroxyl group on the inorganic oxide pigment to attach the hydrolyzed polyether alkoxysilane reactive dispersant to the inorganic oxide pigment.

### Claim 15 (depends on 14)

The method of claim 14, wherein milling is carried out in a bead mill provided with fine beads having diameter of less than 1.0 mm as the grinding medium.

### Claim 16 (depends on 4)

The oxide pigment dispersion of claim 4, wherein m is an integer from 2 to 30.

### Claim 17 (depends on 4)

The oxide pigment dispersion of claim 4, wherein R4 is CH3 or C2H5.

### Claim 18 (depends on 4)

The oxide pigment dispersion of claim 4, wherein PE is a polyethylene glycol (PEG) chain segment (—CH2CH2—O—)m, or a polypropylene glycol (PPG) chain segment (—CH2—CH2—CH2—O—)m, or a mixture thereof.

### Claim 19 (depends on 4)

The oxide pigment dispersion of claim 4, wherein PE is a PEG chain (—CH2CH2—O—)m and m is an integer from 2 to 30.

### Claim 20 (depends on 4)

The metal oxide pigment dispersion of claim 4, wherein the inorganic oxide particles have the particle size in the range of about 5 nm to about 100 nm.

### Claim 21 (depends on 4)

The oxide pigment dispersion of claim 4, wherein R4 is H.

### Claim 22 (depends on 1)

The oxide pigment dispersion of claim 1 wherein a ratio of the polyether alkoxysilane reactive dispersant to the inorganic oxide pigments ranges from 0.3 to 2.0.