Sakata Inx Corporation

Sakata Ink Corp.

Takaaki Yodo

Hideo Shibata

Koji Iwase

Hirohito Maeda

Masanori Kano

Kazunori Itoh

Katsutoshi Okamoto

Naoyuki Kitaoka

Naoya Inazumi

The present invention provides a method for producing a liquid developer for electrophotography or electrostatic recording obtained by a coacervation method, which sufficiently maintains the charging property and has good dispersion stability of colored resin particles, as well as a liquid developer obtained by the method. A method for producing a liquid developer by a coacervation method,

Method for producing liquid developer

Production process for a liquid developer for use in electrophotograph or electrostatic recording by coacervation method. The process can produce a liquid developer in which a coloring agent (e.g., a pigment) is included completely within a resin particle by distillation of a solvent while retaining the state where the coloring agent is finely dispersed and the resulting colored resin particle is small in particle size with excellent dispersion stability, and excellent optical properties.

Process for production of liquid developer, and liquid developer produced by the process

An object of the present invention is to provide a carbodiimide type compound having high dispersibility and dispersion stability of pigments, fine resin particles, and pigment-resin composite fine particles particularly in a silicone dispersion medium; a pigment dispersion composition and a pigment-resin composite fine particles-containing dispersion composition preferably usable in a wide range of fields such as inks for solvent ink jet, liquid developers, and the like by using the compound; and a liquid developer using such a pigment dispersion composition and/or pigment-resin composite fine particles-containing dispersion composition. The present invention provides a carbodiimide type compound obtained by introducing a polysiloxane chain by reaction of a functional group of a polysiloxane chain-containing compound having the functional group reactive with a carbodiimide group with a carbodiimide group of a carbodiimide compound having a carbodiimide equivalent weight of 100 to 50000.

Carbodiimide compound and use thereof

It is an object of the present invention to provide a liquid developer in which in liquid developers for electrophotography or electrostatic recording obtained using the coacervation method, electric resistance of the liquid developer and the electrophoretic property or the charging characteristic of the toner particles are adequately maintained, and the dispersibility of a pigment and the dispersion stability of the toner particles are good. A liquid developer formed by dispersing colored resin particles comprising at least a pigment, a dispersant and a resin in a hydrocarbon insulating medium using a coacervation method,

Liquid developer

A pigment dispersion composition which can be suitably applied in such fields as color filters, black matrices and ink jet recording where it is necessary to finely disperse pigments still with retention of good dispersion stability and temporal stability even when the total amount a pigment derivative, pigment intermediate, colorant derivative and colorant intermediate, and/or a pigment dispersant is small. Another object is a pigment dispersion-based resist composition which can give color filters high in permeability, excellent in contrast and causing no bleeding or black matrices high in light-shielding and insulating properties, and causing no bleeding. And a pigment dispersion composition which is prepared by dispersing a pigment using a pigment derivative, pigment intermediate, colorant derivative and/or colorant intermediate each having a functional group reactive with a carbodiimide group and having adsorption ability on the pigment surface, and a carbodiimide compound containing at least one carbodiimide group.

Pigment dispersion composition, use thereof and compound for pigment treatment

A treated pigment and a dispersion composition thereof having preferable dispersion stability and fluidity in a dispersion medium even the pigment has no functional group reactive with a carbodiimide group on the surface thereof, and further to provide a resist composition exerting very excellent developing characteristics when forming color filters, black matrices and the like patterns. Furthermore, the invention also provides a compound for pigment treatment suited for the treatment of such pigment. A treated pigment which is producible by the treatment with a carbodiimide-based compound having at least one side chain selected from the group consisting of polyester side chains, polyether side chains and polyacrylic side chains and at least one basic nitrogen-containing group within the molecule.

Treated pigment, use thereof, and compound for pigment treatment

The present invention provides a treated pigment produced by treating at least one pigment selected from the group consisting of organic pigments and carbon black each having a functional group reactive with a carbodiimide group with a carbodiimide compound having one or more carbodiimide groups, said carbodiimide compound having, within the molecule thereof, at least one side chain selected from the group consisting of polyester side chains, polyether side chains and polyacrylic side chains, with a carbodiimide equivalent of 100 to 50,000.

Growing community of inventors

Osaka, Japan

Takaaki Yodo