Aqueous ink, ink cartridge and ink jet recording method

Patent metadata

Field	Value
Publication number	US-11492483-B2
Application number	US-202016914554-A
Country	US
Kind code	B2
Filing date	Jun 29, 2020
Priority date	Jul 1, 2019
Publication date	Nov 8, 2022
Grant date	Nov 8, 2022

Abstract

Provided is an aqueous ink for ink jet, containing a resin particle, and a cyclic amide-based, water-soluble organic solvent. The resin particle has a core portion that contains a cyano group-containing unit, and a shell portion that contains an aromatic group-containing unit, an anionic group-containing unit and a unit derived from a crosslinking agent, but free of cyano group-containing unit. Ink jet recording using the aqueous ink can record images that excel in abrasion resistance and gloss clarity.

First claim

What is claimed is:

1. An aqueous ink for ink jet comprising:
a resin particle; and
a water-soluble organic solvent,
wherein the resin particle has a core portion that comprises a cyano group-containing unit, and a shell portion that comprises an aromatic group-containing unit, an anionic group-containing unit, and a unit derived from a crosslinking agent, but free of cyano group-containing unit, and
wherein the water-soluble organic solvent comprises a cyclic amide.

2. The aqueous ink according to claim 1 , wherein the resin particle has a glass transition temperature of 95° C. or more, and a minimum film forming temperature of 30° C. or less.

3. The aqueous ink according to claim 1 , wherein a percentage (% by mass) of the cyano group-containing unit in the core portion is 10% by mass or more to 60% by mass or less.

4. The aqueous ink according to claim 1 , wherein the cyano group-containing unit is a unit derived from at least one of acrylonitrile or methacrylonitrile.

5. The aqueous ink according to claim 1 , wherein the cyclic amide is at least one selected from the group consisting of 2-pyrrolidone, N-methyl-2-pyrrolidone, 1-(2-hydroxyethyl)-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and 1,3-bis(2-hydroxyethyl)-5,5-dimethylhydantoin.

6. The aqueous ink according to claim 1 , wherein the content (% by mass) of the cyclic amide, when expressed in mass ratio relative to the content (% by mass) of the resin particle, is 0.5 times or more to 2.5 times or less.

7. The aqueous ink according to claim 1 , further comprising a water-soluble resin having an acid value of 100 mgKOH/g or more to 180 mgKOH/g or less.

8. The aqueous ink according to claim 1 , further comprising a coloring material.

9. An ink cartridge comprising an ink, and an ink storage portion that stores the ink,
the ink being the aqueous ink as defined in claim 1 .

10. An ink jet recording method by which an image is recorded on a recording medium with an ink ejected from a recording head of an ink jet system,
the ink being the aqueous ink as defined in claim 1 .

Assignees

• Canon Kk

Inventors

• Kishi Hiromitsu
• Okamura Daiji
• Miyamachi Naotoshi
• Inui Keisuke
• Yuasa Hirohiko
• Shimomura Naofumi

Classifications

• C09D133/20 Primary

  Homopolymers or copolymers of acrylonitrile (C09D155/02 takes precedence) · CPC title

• C09D151/003

  grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds (C09D151/04, C09D151/06 take precedence) · CPC title

• C08L2207/53

  Core-shell polymer · CPC title

• B41J2/17553

  Outer structure · CPC title

• C09D11/30

  Inkjet printing inks · CPC title