Water-based inkjet yellow ink, ink set, and method for producing printed matter

Patent metadata

Field	Value
Publication number	US-12325802-B2
Application number	US-201917414500-A
Country	US
Kind code	B2
Filing date	Dec 16, 2019
Priority date	Dec 17, 2018
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

Abstract

One embodiment relates to a water-based inkjet yellow ink containing a yellow pigment (A) having a specific partial structure, an organic solvent, a basic organic compound, and water, wherein an amount of the yellow pigment (A) is 1 to 10% by mass of a total mass of the water-based inkjet yellow ink, the basic organic compound contains 0.1 to 1.25% by mass of a basic organic compound (B) having a pKa value of 9.5 or less at 25° C. of the total mass of the water-based inkjet yellow ink, and an amount of an organic solvent having a boiling point of 240° C. or higher under 1 atmosphere is 5% by mass or less of the total mass of the water-based inkjet yellow ink.

First claim

The invention claimed is:

1. A water-based inkjet yellow ink comprising:
a yellow pigment (A) having a partial structure represented by general formula (1), an organic solvent, a basic organic compound, a binder resin, and water, wherein
an amount of the yellow pigment (A) is 1 to 10% by mass of a total mass of the water-based inkjet yellow ink;
the basic organic compound contains 0.1 to 1.25% by mass of a basic organic compound (B) having a pKa value of 9.5 or less at 25° C. of the total mass of the water-based inkjet yellow ink,
an amount of an organic solvent having a boiling point of 240° C. or higher under 1 atmosphere is 5% by mass or less of the total mass of the water-based inkjet yellow ink, and
the binder resin includes olefin resin microparticles, and
if an amine value of the yellow pigment (A) is Am (PA) [mgKOH/g], the amount of the yellow pigment (A) of the total mass of the water-based inkjet yellow ink is C (PA) [% by mass], an acid value of the olefin resin microparticles is Av (RO) [mgKOH/g], and an amount of the olefin resin microparticles of the total mass of the water-based inkjet yellow ink is C (RO) [% by mass], the acid value/amine value ratio represented by formula (8) shown below is 0.5×10 −4 to 15×10 −4 ,

wherein, general formula (1) has at least one bonding site, and
in general formula (1),
X 1 and X 2 represent both ═O or both ═CR 6 R 7 , or X 1 is ═O and X 2 is ═NR 8 ,
each R 1 to R 4 independently represents a hydrogen atom or a halogen atom,
R 5 represents a hydrogen atom or a bonding site,
each R 6 to R 8 represents a bonding site, and
Acid value/amine value ratio={Av(RO)×C(RO)}÷{Am(PA)×C(PA)}  formula (8).

2. The water-based inkjet yellow ink according to claim 1 , wherein
an amount of the basic organic compound (B) having a pKa value of 9.5 or less at 25° C. is 0.1 to 1% by mass of the total mass of the water-based inkjet yellow ink.

3. The water-based inkjet yellow ink according to claim 1 , wherein
the yellow pigment (A) includes C. I. Pigment Yellow 139 and/or C. I. Pigment Yellow 185.

4. The water-based inkjet yellow ink according to claim 1 , wherein
an amount of impurities contained in the yellow pigment (A) is 5% by mass or less of a total mass of the yellow pigment (A).

5. A inkjet ink set comprising:
the water-based inkjet yellow ink according to claim 1 , and
a water-based inkjet magenta ink containing magenta pigment and water.

Assignees

• Artience Co Ltd
• Toyocolor Co Ltd

Inventors

• Yoda Atsushi
• Jonai Kazuhiro
• Suzuki Norio

Classifications

• C09D11/322

  Pigment inks · CPC title

• C09D11/107

  from unsaturated acids or derivatives thereof · CPC title

• C09D11/037

  characterised by the pigment · CPC title

• C09D11/033

  characterised by the solvent · CPC title

• C09B57/04

  Isoindoline dyes · CPC title