Ink set and image forming method

• US 10,639,919 B2
• Filed: 08/16/2017
• Issued: 05/05/2020
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Arai, Takuya, Hokazono, Hirohisa
• Primary Examiner(s): Klemanski, Helene
• Application Number:
  US15/678,139
• Publication Number:
  US 20180056691A1
• Time in Patent Office: 993 Days
• Field of Search: None
• CPC Class Codes: B41M 5/0023 Digital printing methods characterised by the inks used inks per se C09D11/00
• CPC Class Codes: B41M 7/0081 using electromagnetic radiation or waves, e.g. ultraviolet radiation, electron beams
• CPC Class Codes: B41M 7/009 using thermal means, e.g. infrared radiation, heat
• CPC Class Codes: C09D 11/101 Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing
• CPC Class Codes: C09D 11/106 containing macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C09D 11/12 based on waxes or bitumen
• CPC Class Codes: C09D 11/322 Pigment inks
• CPC Class Codes: C09D 11/324 containing carbon black
• CPC Class Codes: C09D 11/38 characterised by non-macromolecular additives other than solvents, pigments or dyes
• CPC Class Codes: C09D 11/40 Ink-sets specially adapted for multi-colour inkjet printing
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: C09D 11/54 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

Abstract

The invention provides an ink set and an image forming method in which excellent glossiness is obtained in a case where a surface of an image recording material on which an image is formed using an acidic pre-treatment liquid is overcoated. Namely, the invention provides an ink set and an image forming method using the same, the ink set including: an ink composition which includes a colorant and water; a pre-treatment liquid which contains an acid and water; and an overcoat liquid which includes water and particles of a resin, the resin containing an acidic group selected from the group consisting of a sulfo group, a salt of a sulfo group, a phosphonic acid group, a salt of a phosphonic acid group, a phosphoric acid group, and a salt of a phosphoric acid group.

Claims

1. An ink set, comprising:

an ink composition comprising a colorant and water;

a pre-treatment liquid comprising an organic acidic compound containing a carboxy group, and water; and

an overcoat liquid comprising water and particles of a resin, the resin comprising a first acidic group selected from the group consisting of a sulfo group, a salt of a sulfo group, a phosphonic acid group, a salt of a phosphonic acid group, a phosphoric acid group, and a salt of a phosphoric acid group,

wherein the particles respectively comprise, in at least a part of a surface thereof, a surfactant comprising a second acidic group selected from the group consisting of a sulfo group, a salt of a sulfo group, a phosphonic acid group, a salt of a phosphonic acid group, a phosphoric acid group, and a salt of a phosphoric acid group,

wherein a total content A of the first acidic group is in a range of from 0.10 mmol to 1.8 mmol per 1 g of the resin,

wherein a total content B of the second acidic group is in a range of from 0.02 mmol to 0.30 mmol per 1 g of the resin, and

wherein a ratio of the total content B to the total content A is in a range of from 0.1 to 0.8.

2. The ink set according to claim 1, wherein the acidic group included in the resin includes at least one selected from the group consisting of a sulfo group and a salt of a sulfo group.

3. The ink set according to claim 1, wherein the acidic group contained in the surfactant is a sulfo group or a salt of a sulfo group.

4. The ink set according to claim 1, wherein the resin contained in the particles does not contain a carboxy group.

5. An image forming method, comprising:

applying a pre-treatment liquid comprising an organic acidic compound containing a carboxy group, and water to an image recording material;

applying, to a surface of the image recording material to which the pre-treatment liquid is applied, an ink composition comprising a colorant and water to form an image; and

applying, to at least a part of a side of the image recording material on which the image is formed, an overcoat liquid comprising water and particles of a resin, the resin comprising a first acidic group selected from the group consisting of a sulfo group, a salt of a sulfo group, a phosphonic acid group, a salt of a phosphonic acid group, a phosphoric acid group, and a salt of a phosphoric acid group,

wherein the particles respectively comprise, in at least a part of a surface thereof, a surfactant comprising a second acidic group selected from the group consisting of a sulfo group, a salt of a sulfo group, a phosphonic acid group, a salt of a phosphonic acid group, a phosphoric acid group, and a salt of a phosphoric acid group,

wherein a total content A of the first acidic group is in a range of from 0.10 mmol to 1.8 mmol per 1 g of the resin,

wherein a total content B of the second acidic group is in a range of from 0.02 mmol to 0.30 mmol per 1 g of the resin, and

wherein a ratio of the total content B to the total content A is in a range of from 0.1 to 0.8.