# US 12,595,386 B2 · Aqueous ink, ink cartridge and ink jet recording method

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- Number: US 12,595,386 B2
- Document ID: US12595386B2
- Status: Granted
- Kind: B2
- Application number: 18/071,666
- Filed: 2022-11-30
- Published: 2023-06-08
- Granted: 2026-04-07
- Earliest claimed: 2021-12-07
- Assignees: Canon Kabushiki Kaisha
- Applicants: Canon Kabushiki Kaisha
- Inventors: Katsuhiro Hayashi; Keiichi Ito; Tsuyoshi Furuse
- Web page: https://patentgrep.com/patent/US12595386B2

## CPC

- C09D 11/32: characterised by colouring agents
- B41J 2/01: Ink jet
- B41J 2/2107: {characterised by the ink properties (supplying ink in a solid state B41J2/17593)}
- C09D 11/104: Polyesters
- C09D 11/322: Pigment inks
- C09D 11/326: characterised by the pigment dispersant
- 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)
- B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS

## Abstract

Provided is an aqueous ink for ink jet containing coloring material-particle and resin particle. The resin particle is formed from a crystalline polyester resin having carboxylic acid groups. A difference between a 50% cumulative particle diameter (D50C) in a volume-based particle size distribution of the coloring material-particle and a 50% cumulative particle diameter (D50R) in a volume-based particle size distribution of the resin particle (D50C−D50R) is 10 nm or more. In addition, an ink cartridge and an ink jet recording method using this aqueous ink are provided.

## Claims

### Claim 1

An aqueous ink for ink jet comprising a coloring material-particle and a resin particle,
wherein the resin particle is formed of a crystalline polyester resin having a carboxylic acid group; and
wherein a difference (D50C−D50R) of a 50% cumulative particle diameter (D50C) in a volume-based particle size distribution of the coloring material-particle minus a 50% cumulative particle diameter (D50R) in a volume-based particle size distribution of the resin particle is 10 nm or more.

### Claim 2 (depends on 1)

The aqueous ink according to claim 1, wherein the D50C−D50R is 150 nm or less.

### Claim 3 (depends on 1)

The aqueous ink according to claim 1, wherein the D50C−D50R is 100 nm or less.

### Claim 4 (depends on 1)

The aqueous ink according to claim 1, wherein the D50R is 5 nm or more to 30 nm or less.

### Claim 5 (depends on 1)

The aqueous ink according to claim 1, wherein a ratio of the D50R to a 90% cumulative particle diameter (D90R) in the volume-based particle size distribution of the resin particle is 0.6 times or more.

### Claim 6 (depends on 1)

The aqueous ink according to claim 1, wherein a mass ratio of a content (% by mass) of the coloring material-particle to a content (% by mass) of the resin particle is 1.0 times or more to 100.0 times or less.

### Claim 7 (depends on 1)

An ink cartridge comprising an ink and an ink storage portion that stores the ink therein, wherein the ink comprises the aqueous ink according to claim 1.

### Claim 8 (depends on 7)

The ink cartridge according to claim 7, wherein the D50C−D50R is 150 nm or less.

### Claim 9 (depends on 7)

The ink cartridge according to claim 7, wherein the D50C−D50R is 100 nm or less.

### Claim 10 (depends on 7)

The ink cartridge according to claim 7, wherein the D50R is 5 nm or more to 30 nm or less.

### Claim 11 (depends on 7)

The ink cartridge according to claim 7, wherein a ratio of the D50R to a 90% cumulative particle diameter (D90R) in the volume-based particle size distribution of the resin particle is 0.6 times or more.

### Claim 12 (depends on 7)

The ink cartridge according to claim 7, wherein a mass ratio of a content (% by mass) of the coloring material-particle to a content (% by mass) of the resin particle is 1.0 times or more to 100.0 times or less.

### Claim 13 (depends on 1)

An ink jet recording method comprising recording an image onto a recording medium by ejecting an ink from an ink jet recording head, wherein the ink comprises the aqueous ink according to claim 1.