Pigment dispersion and ink composition, curable composition and curable ink composition making use of the same

• US 8,912,248 B2
• Filed: 03/02/2010
• Issued: 12/16/2014
• Est. Priority Date: 03/23/2009
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Shimohara, Norihide
• Primary Examiner(s): Blackwell, Gwendolyn
• Assistant Examiner(s): Zhang, Ruiyun
• Application Number:
  US12/715,414
• Publication Number:
  US 20100240830A1
• Time in Patent Office: 1,750 Days
• Field of Search: 523/160, 523/161, 524/589
• US Class Current: 523/160
• CPC Class Codes: C08G 18/2865 Compounds having only one primary or secondary amino group; Ammonia
• CPC Class Codes: C08G 18/3215 containing aromatic groups or benzoquinone groups
• CPC Class Codes: C08G 18/38 having heteroatoms other than oxygen C08G18/32 takes precedence
• CPC Class Codes: C08G 18/4277 Caprolactone and/or substituted caprolactone
• CPC Class Codes: C08G 18/622 Polymers of esters of alpha-beta ethylenically unsaturated carboxylic acids
• CPC Class Codes: C08G 18/6511 compounds of group C08G18/3203
• CPC Class Codes: C08G 18/664 with compounds of group C08G18/3203
• CPC Class Codes: C08G 18/8116 esters of acrylic or alkylacrylic acid having only one isocyanate or isothiocyanate group
• CPC Class Codes: C09B 69/101 containing an anthracene dye
• CPC Class Codes: C09B 69/109 containing other specific dyes
• 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 11/326 characterised by the pigment dispersant
• CPC Class Codes: C09D 17/003 containing an organic pigment process features in the making of dye stuff preparations C09B67/00

Abstract

The present invention provides a pigment dispersion, containing (a) a pigment; and (b) a polymer having a polyurethane bond in a main chain, having at least one polymer chain selected from the group consisting of a polyester, a polyacrylate, a polymethacrylate and a polyalkylene oxide at a side chain of the polymer, and having a partial skeleton that is different from a partial skeleton included in a chemical structure of the pigment, as a pendant of the main chain.

Claims

1. A pigment dispersion, comprising:

(a) a pigment; and

(b) a polymer having a polyurethane backbone, the polymer comprising;

at least one polymer side chain selected from the group consisting of a polyester, a polyacrylate, a polymethacrylate and a polyalkylene oxide; and

a pendant, of a polyurethane part of a main chain of the polymer, comprising a partial skeleton, the partial skeleton being different from a partial skeleton included in a chemical structure of the pigment;

wherein the pigment is selected from the group consisting of azo pigment, diketopyrrolopyrrole pigment, dioxazine violet pigment, phthalocyanine pigment, and carbon black pigment; and

when the pigment is an azo pigment, the partial skeleton of the pendant is selected from the group consisting of an acridone structure, a naphthalimide structure and an anthraquinone structure,

when the pigment is a diketopyrrolopyrrole pigment, the partial skeleton of the pendant is a naphthalimide structure or an acridone structure,

when the pigment is a dioxazine violet pigment, the partial skeleton of the pendant is a naphthalimide structure,

when the pigment is a phthalocyanine pigment, the partial skeleton of the pendant is a naphthalimide structure or an acridone structure, and

when the pigment is a carbon black pigment, the partial skeleton of the pendant is an acridone structure.

2. The pigment dispersion of claim 1, wherein an average particle size of the pigment is from 0.01 to 0.4 μ

m.

3. The pigment dispersion of claim 1, wherein a content of the pigment in the pigment dispersion is from 1 to 40% by weight in terms of solid content.

4. The pigment dispersion of claim 1, wherein a weight average molecular weight of the polymer is from 5,000 to 200,000.

5. An ink composition comprising the pigment dispersion of claim 1 and a liquid medium having affinity with the polymer of the pigment dispersion.

6. A curable composition comprising the pigment dispersion of claim 1 and (c) a polymerizable compound.

7. A curable ink composition comprising the curable composition of claim 6.

8. The pigment dispersion of claim 1, wherein the polymer is obtained by a reaction of compounds including a first compound having one or two hydroxyl groups or one or two isocyanate groups together with the partial skeleton which is different from the partial skeleton included in the chemical structure of the pigment, a second compound which is selected from a polyester, a polyacrylate, a polymethacrylate and a polyalkylene oxide, all of which having one or two hydroxyl groups, and a third compound having at least two isocyanate groups, which is different from the first compound, and the reaction is conducted in the presence of a polymerizable compound.

9. The curable ink composition of claim 7, wherein the curable ink composition is solventless.

10. A pigment dispersion, comprising:

(a) a pigment; and

(b) a polymer having a polyurethane backbone, the polymer comprising;

at least one polymer side chain selected from the group consisting of a polyester, a polyacrylate, a polymethacrylate and a polyalkylene oxide; and

a pendant, of a polyurethane part of a main chain of the polymer, comprising a partial skeleton, the partial skeleton being different from a partial skeleton included in a chemical structure of the pigment;

wherein the pigment is selected from the group consisting of diketopyrrolopyrrole pigment, dioxazine violet pigment, phthalocyanine pigment, and carbon black pigment; and

when the pigment is a diketopyrrolopyrrole pigment, the partial skeleton of the pendant is a naphthalimide structure or an acridone structure,

when the pigment is a dioxazine violet pigment, the partial skeleton of the pendant is a naphthalimide structure,

when the pigment is a phthalocyanine pigment, the partial skeleton of the pendant is a naphthalimide structure or an acridone structure, and

when the pigment is a carbon black pigment, the partial skeleton of the pendant is an acridone structure.

11. The pigment dispersion of claim 10, wherein (b) the polymer having a polyurethane backbone has at least one polymer chain selected from a polyacrylate or a polymethacrylate at a side chain of the polymer.