Surface modification of pigments and compositions comprising the same

Patent metadata

Field	Value
Publication number	US-8927648-B2
Application number	US-201313796379-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	May 4, 2012
Publication date	Jan 6, 2015
Grant date	Jan 6, 2015

Abstract

Disclosed herein is a method of making a modified pigment, comprising: reacting, under Mitsunobu conditions: (a) a first reactant comprising a protonated nucleophile having a pK a <15, and (b) a second reactant comprising a hydroxyl-containing organic group, wherein a pigment is attached to either the first or second reactant. The method further comprises forming the modified pigment having attached an organic species comprising the nucleophile bonded to the organic group, with the net elimination of a proton and a hydroxyl. Also disclosed herein are modified pigments, which can have applications in chemical toners, inkjet ink and electrophoretic ink compositions, black matrix materials, color filters, and coatings.

First claim

The invention claimed is:

1. A method of making a modified pigment, comprising:
reacting, under Mitsunobu conditions:
(a) a first reactant comprising a protonated nucleophile having a pK a <15, and
(b) a second reactant comprising a hydroxyl-containing organic group, wherein a pigment is attached to either the first or second reactant, and
forming the modified pigment having attached an organic species comprising the nucleophile bonded to the organic group, with the net elimination of a proton and a hydroxyl.

2. The method of claim 1 , wherein the pigment is attached to the first reactant.

3. The method of claim 1 , wherein the protonated nucleophile is carboxylic acids, phenols, naphthols, or phthalimides.

4. The method of claim 1 , wherein the hydroxyl-containing organic group is primary alcohols or secondary alcohols.

5. The method of claim 1 , wherein the reactant not attached to the pigment comprises a polymer.

6. The method of claim 5 , wherein the polymer is hydroxyl-containing polymers.

7. The method of claim 1 , wherein the nucleophile is bonded to the organic group via linkages wherein the linkages are phenyl ester, phenyl ethers, naphthol esters, naphthol ethers, or phthalimides.

8. The method claim 1 , wherein the Mitsunobu conditions includes reagents comprising:
(a) trialkylphosphines or triarylphosphines, and
(b) azodicarboxylate esters or azodicarboxylate amides.

9. The method of claim 1 , wherein the pigment is carbon black pigments or organic pigments.

10. The method of claim 1 , wherein the pigment is carbon black pigments and the protonated nucleophile is selected from phenols, naphthols, or carboxylic acids.

11. The method of claim 1 , wherein the pigment is an organic pigment and the protonated nucleophile is phenols, naphthols, phthalimides, isoindoline, amides, or imides.

12. The method of claim 11 , wherein the organic pigment is Pigment Yellow 185 or Pigment Red 269.

Assignees

• Cabot Corp

Inventors

• Zhang Qingling
• Larochelle Richard Lynne K

Classifications

• C09B68/41

  Polymers attached to the pigment surface (C09B68/444, C09B68/446 take precedence) · CPC title

• C01P2002/87

  by chromatography data, e.g. HPLC, gas chromatography · CPC title

• C09C1/48

  Carbon black · CPC title

• C01P2004/54

  Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension · CPC title

• C09D5/00

  Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced {(electrically insulating plastics, resins or waxes H01B3/30)}; Filling pastes · CPC title