US 7,683,108 B2 · Microencapsulated pigment, production process therefor, aqueous dispersion, and ink jet recording ink

Abstract

Provided are ink jet ink excellent in dispersion stability and ejection stability and capable of forming images with fastness, abrasion resistance, color developability, and high density with little feathering; a microencapsulated pigment (MCP) providing the ink and a process of making the same; and an aqueous dispersion of the MCP. The MCP comprises pigment particles having a hydrophilic group on their surface (hydrophilized pigment particles) and coated with a polymer by emulsion polymerization. The process comprises emulsion polymerization in the presence of the hydrophilized pigment particles. The ink essentially contains the MCP and water.

Claims26

Dependent claims

A microencapsulated pigment comprising a plurality of pigment particles, each of the pigment particles having a hydrophilic group on the surface thereof and being coated with a polymer to form a polymer coating, wherein the polymer is prepared by polymerizing at least one of a polymerizable surface active agent having a hydrophilic group, a hydrophobic group and a polymerizable group, and a hydrophilic monomer in the presence of a polymeric azo initiator comprising a repeating unit represented by formula (I):

wherein D represents a portion having at least a hydrophobic segment;
L1 and L2, which may be the same or different, each represent a linking group;
R1, R2, R3, and R4 each represent an alkyl group having 1 to 4 carbon atoms or a cyano group;
and n represents an integer of 1 or greater.

1 more element

A process for producing a microencapsulated pigment, comprising

coating pigment particles having a hydrophilic group on the surface thereof with a polymer to form a polymer coating,
wherein said polymer is prepared by polymerizing at least one of a polymerizable surface active agent having a hydrophilic group, a hydrophobic group and a polymerizable group, and a hydrophilic monomer in the presence of a polymeric azo initiator comprising a repeating unit represented by formula (I):
wherein D represents a portion having at least a hydrophobic segment;
L1 and L2, which may be the same or different, each represent a linking group;
R1, R2, R3, and R4 each represent an alkyl group having 1 to 4 carbon atoms or a cyano group;
and n represents an integer of 1 or greater.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

11/373,680Filed 10 Mar 2006 · division

Priority

JP P.2001-25602527 Aug 2001

Published

US 2006/0155008 A113 Jul 2006

Granted

23 Mar 2010

Term ends

Not estimatedThe source records don’t support an estimate.

Classification24 codes

C09C 1/56
Carbon black: treatment of carbon black ; Purification
B01J 13/04
Making microcapsules or microballoons: by physical processes, e.g. drying, spraying
B01J 13/14
By phase separation: polymerisation; cross-linking
C09B 67/0013
With organic coatings: with polymeric coatings

Microencapsulated pigment, production process therefor, aqueous dispersion, and ink jet recording ink

Life of this patent

Microencapsulated pigment, production process therefor, aqueous dispersion, and ink jet recording ink

Life of this patent

Abstract

Claims26