Aqueous inkjet pigment dispersion, method for producing same, and aqueous inkjet ink

Patent metadata

Field	Value
Publication number	US-2016369117-A1
Application number	US-201615249478-A
Country	US
Kind code	A1
Filing date	Aug 29, 2016
Priority date	Mar 31, 2014
Publication date	Dec 22, 2016
Grant date	—

Abstract

Provided are a method for producing an aqueous inkjet pigment dispersion, including producing a mixed liquid of water, a pigment, a pigment dispersing polymer, and rosin acid in an amount of from 3% by mass to 30% by mass relative to the total mass of the pigment, and reducing the amount of rosin acid included in the produced mixed liquid, to less than 3.0% by mass relative to the total mass of the pigment; an aqueous inkjet pigment dispersion; and an aqueous inkjet ink.

First claim

What is claimed is:

1 . A method for producing an aqueous inkjet pigment dispersion, the method comprising:
producing a mixed liquid of water, a pigment, a pigment dispersing polymer, and rosin acid in an amount of from 3% by mass to 30% by mass relative to the total mass of the pigment; and reducing the amount of rosin acid included in the produced mixed liquid, to less than 3.0% by mass relative to the total mass of the pigment.

2 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the amount of rosin acid after the reducing of the amount of rosin acid is 0.25% by mass or more and less than 3.0% by mass relative to the total mass of the pigment.

3 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the reducing of the amount of rosin acid involves reducing the amount of rosin acid using ultrafiltration.

4 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , further comprising crosslinking the pigment dispersing polymer, after the producing of a mixed liquid.

5 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the producing of a mixed liquid involves mixing the pigment and rosin acid, and then mixing the resultant with the pigment dispersing polymer.

6 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the acid value of the pigment dispersing polymer is 90 mg KOH/g to 150 mg KOH/g.

7 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the acid value of the pigment dispersing polymer is 100 mg KOH/g to 120 mg KOH/g.

8 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the pigment dispersing polymer has a hydrophilic structural unit and a hydrophobic structural unit.

9 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the pigment dispersing polymer has a hydrophilic structural unit derived from (meth)acrylic acid, and a hydrophobic structural unit derived from at least one selected from C 1 -C 20 alkyl (meth)acrylate and derivatives thereof, benzyl (meth)acrylate and derivatives thereof, and phenoxyethyl (meth)acrylate and derivatives thereof.

10 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein in the producing of a mixed liquid, a compound having an acetylenediol group is further incorporated.

11 . The method for producing an aqueous inkjet pigment dispersion according to claim 1 , wherein the rosin acid is a mixture comprising one or more selected from abietic acid and a salt thereof, neoabietic acid and a salt thereof, dehydroabietic acid and a salt thereof, palustric acid and a salt thereof, levopimaric acid and a salt thereof, pimaric acid and a salt thereof, isopimaric acid and a salt thereof, and citronellic acid and a salt thereof.

12 . An aqueous inkjet pigment dispersion comprising:
water; a pigment coated with a pigment dispersing polymer; and rosin acid in an amount of 0.25% by mass or more and less than 3.0% by mass relative to the total mass of the pigment, wherein the aqueous inkjet pigment dispersion has a polydispersity index of 1.10 to 1.45.

13 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the pigment dispersing polymer has a crosslinked structure.

14 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the acid value of the pigment dispersing polymer is 90 mg KOH/g to 150 mg KOH/g.

15 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the acid value of the pigment dispersing polymer is 100 mg KOH/g to 120 mg KOH/g.

16 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the pigment dispersing polymer has a hydrophilic structural unit and a hydrophobic structural unit.

17 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the pigment dispersing polymer has a hydrophilic structural unit derived from (meth)acrylic acid, and a hydrophobic structural unit derived from at least one selected from C 1 -C 20 alkyl (meth)acrylate and derivatives thereof, benzyl (meth)acrylate and derivatives thereof, and phenoxyethyl (meth)acrylate and derivatives thereof.

18 . The aqueous inkjet pigment dispersion according to claim 12 , further comprising a compound having an acetylenediol group.

19 . The aqueous inkjet pigment dispersion according to claim 12 , wherein the rosin acid is a mixture comprising one or more selected from abietic acid and a salt thereof, neoabietic acid and a salt thereof, dehydroabietic acid and a salt thereof, palustric acid and a salt thereof, levopimaric acid and a salt thereof, pimaric acid and a salt thereof, isopimaric acid and a salt thereof, and citronellic acid and a salt thereof.

20 . An aqueous inkjet ink comprising the aqueous inkjet pigment dispersion according to claim 12 .

Assignees

• Fujifilm Corp

Inventors

• Nishimura Naoko

Classifications

• C09B67/009

  polymeric dispersing agent · CPC title

• C09D17/00

  Pigment pastes, e.g. for mixing in paints (artists' paints C09D5/06) · CPC title

• C09B67/0013

  with polymeric coatings · CPC title

• C09D11/107

  from unsaturated acids or derivatives thereof · CPC title

• C09D11/104

  Polyesters · CPC title