Ink set and method for producing printed matter

Patent metadata

Field	Value
Publication number	US-11453797-B2
Application number	US-201816630583-A
Country	US
Kind code	B2
Filing date	Jul 13, 2018
Priority date	Jul 14, 2017
Publication date	Sep 27, 2022
Grant date	Sep 27, 2022

Abstract

An ink set containing an inkjet ink and a treatment liquid, wherein the inkjet ink contains a pigment, a water-soluble organic solvent, a surfactant and water, the water-soluble organic solvent contains an alkyl diol (A) of 2 to 8 carbon atoms, the weighted average boiling point of the water-soluble organic solvent at one atmosphere is from 175 to 240° C., the surfactant contains an acetylenediol-based surfactant, the treatment liquid contains a coagulant, calcium nitrate is included as the coagulant in an amount of 6.8 to 20.8% by mass relative to the total mass of the treatment liquid, and the pH of the treatment liquid is from 2 to 11.

First claim

The invention claimed is:

1. An ink set comprising an inkjet ink, and a treatment liquid used in combination with the inkjet ink, wherein
the inkjet ink comprises a pigment, a water-soluble organic solvent, a surfactant and water,
the water-soluble organic solvent comprises an alkyl diol (A) of 2 to 8 carbon atoms, and a weighted average boiling point of the water-soluble organic solvent at one atmosphere is within a range from 175 to 240° C.,
the surfactant comprises an acetylenediol-based surfactant,
the treatment liquid comprises a coagulant,
calcium nitrate is included as the coagulant in an amount of 6.8 to 20.8% by mass relative to a total mass of the treatment liquid, and
a pH of the treatment liquid is within a range from 2 to 11.

2. The ink set according to claim 1 , wherein a pH of the treatment liquid is from 3.5 to 11.

3. The ink set according to claim 1 , wherein
the treatment liquid further comprises an organic solvent, and
the organic solvent comprises less than 10% by mass of organic solvent having a boiling point at one atmosphere of at least 240° C. relative to a total mass of the treatment liquid.

4. The ink set according to claim 1 , wherein the inkjet ink further comprises a pigment dispersing resin.

5. The ink set according to claim 4 , wherein an acid value of the pigment dispersing resin is within a range from 30 to 300 mgKOH/g.

6. The ink set according to claim 4 , wherein an acid value of the pigment dispersing resin is from 100 to 300 mgKOH/g.

7. The ink set according to claim 4 , wherein the pigment dispersing resin comprises a water-soluble pigment dispersing resin, and a weight average molecular weight (Mw) of the water-soluble pigment dispersing resin satisfies 10,000≤Mw≤40,000.

8. The ink set according to claim 1 , wherein the alkyl diol (A) has 3 to 6 carbon atoms.

9. The ink set according to claim 1 , wherein the treatment liquid also comprises a pH adjuster.

10. The ink set according to claim 1 , wherein a viscosity of the treatment liquid is within a range from 5 to 100 mPa·s.

11. The ink set according to claim 1 , wherein an amount of the calcium nitrate is within a range from 7.0 to 20.5% by mass relative to a total mass of the treatment liquid.

12. A method for producing inkjet ink printed matter that uses the ink set according to claim 1 , the method comprising:
a step of applying the treatment liquid to a recording medium formed from a paper substrate or a synthetic paper substrate, and
a step of applying the inkjet ink by one-pass printing to a portion to which the treatment liquid has been applied.

13. The method for producing inkjet ink printed matter according to claim 12 , wherein the step of applying the treatment liquid is conducted so that an amount of calcium ions on a surface of the recording medium is within a range from 0.5 to 5 mmol/m 2 .

14. A Printed matter obtained by printing the ink set according to claim 1 to a recording medium.

Assignees

• Toyo Ink Sc Holdings Co Ltd
• Toyocolor Co Ltd

Inventors

• Okamoto Mayuko
• Jonai Kazuhiro
• Yoda Atsushi
• Suzuki Norio

Classifications

• C09D11/54 Primary

  Inks based on two liquids, one liquid being the ink, the other liquid being a reaction solution, a fixer or a treatment solution for the ink · CPC title

• C09D11/322

  Pigment inks · CPC title

• C08K3/28

  Nitrogen-containing compounds · CPC title

• C09D11/106

  containing macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C08K5/053

  Polyhydroxylic alcohols · CPC title