Kao Corporation

Tatsuya Yamada

Nobumichi Kamiyoshi

Kunihiro Kano

Akito Itoi

Yoko Hanada

Shingo Takada

Yuri Nannichi

Taiki Yamamoto

Hiromi Ito

A liquid developer containing a resin binder, a colorant, a dispersant, and an insulating liquid, wherein the resin binder contains a resin having an acidic group, and wherein the dispersant contains a dispersant X having at least one basic nitrogen-containing group selected from the group consisting of an amino group, an imino group, a cyano group, an azo group, a diazo group, and an azide group, and wherein a melting point of the dispersant X is 34&#xb0; C. or higher; and a method for printing a fused image using the liquid developer. The liquid developer of the present invention is suitably used in development or the like of latent images formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method or the like.

Liquid developer

A liquid developer containing toner particles containing a resin binder containing a polyester-based resin and a colorant, a dispersant, and an insulating liquid, wherein the dispersant contains a dispersant X having an adsorbing group having a nitrogen-containing group represented by the formula (I): wherein each of R, R, and R, which may be identical or different, is an alkylene group having 1 or more carbon atoms and 22 or less carbon atoms, an alkenylene group having 2 or more carbon atoms and 22 or less carbon atoms, an alkynylene group having 2 or more carbon atoms and 22 or less carbon atoms, or an arylene group having 6 or more carbon atoms and 22 or less carbon atoms, and a dispersing group having a hydrocarbon group having a number-average molecular weight of 500 or more, and wherein the dispersant X has a mass ratio of the adsorbing group to the dispersing group (adsorbing group/dispersing group) of 1/99 or more and 42/58 or less, and a proportion of the dispersing group having a hydrocarbon group having a number-average molecular weight of 500 or more in all the dispersing groups of 55% by mass or more. The liquid developer of the present invention is suitably used in development or the like of latent images formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method or the like.

A liquid developer containing toner particles containing a resin and a pigment, wherein the toner particles are dispersed in an insulating liquid, wherein the resin contains a resin H having a softening point of 100&#xb0; C. or higher and a resin L having a softening point of 93&#xb0; C. or lower, wherein the resin H is a composite resin HC of a polyester resin and a styrenic resin, and the resin L is a polyester resin LP or a composite resin LC of a polyester resin and a styrenic resin, wherein the composite resin HC and the composite resin LC are each a resin in which a polyester resin and a styrenic resin are chemically bonded via a dually reactive monomer, and a method for producing the same. The liquid developer of the present invention is suitably used in development or the like of latent images formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method or the like.

A liquid developer containing toner particles containing a resin containing a polyester and a pigment, wherein the toner particles are dispersed in an insulating liquid in the presence of a dispersant, wherein the insulating liquid has a boiling point of 300&#xb0; C. or lower, and wherein the insulating liquid has a peak intensity ratio of a methyl group calculated by the formula (1): wherein A is a peak intensity ascribed to CHstretching vibration when measured with a Fourier transform infrared spectrometer, B is a total peak intensity ascribed to CHstretching vibration and CH stretching vibration,of 25% or more, or wherein the insulating liquid contains a polyisobutene.

A liquid developer containing toner particles containing a resin containing a polyester and a pigment, wherein the toner particles are dispersed in an insulating liquid in the presence of a dispersant, wherein the insulating liquid has an evaporation rate after holding at 40&#xb0; C. for 30 minutes of less than 0.26% by mass; and a method for producing a liquid developer containing toner particles containing a resin containing a polyester and a pigment, wherein the toner particles are dispersed in an insulating liquid in the presence of a dispersant, including: step 1: melt-kneading a resin containing a polyester and a pigment, and pulverizing a kneaded product obtained, to provide toner particles; step 2: adding a dispersant to the toner particles obtained in the step 1, and dispersing the toner particles in an insulating liquid to provide a dispersion of toner particles, and step 3: subjecting the dispersion of toner particles obtained in the step 2 to wet-milling, to provide a liquid developer, wherein the insulating liquid has an evaporation rate after holding at 40&#xb0; C. for 30 minutes of less than 0.26% by mass. The liquid developer of the present invention is suitably used, for example, in development or the like of latent images formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

A liquid developer containing toner particles containing a resin binder and a pigment, wherein the toner particles are dispersed in an insulating liquid in the presence of a dispersant, wherein the resin binder contains a polyester resin P having a glass transition temperature of 35&#xb0; C. or higher, obtained by polycondensing raw material monomers containing an alcohol component comprising an aliphatic diol having 2 or more carbon atoms and 6 or less carbon atoms in an amount of 70% by mol or more and 100% by mol or less, and a carboxylic acid component, and wherein the dispersant contains a copolymer C prepared by polymerizing a monomer A having an amino group and a monomer B represented by the formula (I): wherein Ris a hydrogen atom or a methyl group; and Ris an alkyl group having 1 or more carbon atoms and 22 or less carbon atoms or an alkenyl group having 2 or more carbon atoms and 22 or less carbon atoms, each of which may have a substituent, wherein a molar ratio of the monomer A to the monomer B (monomer A/monomer B) is 2/98 or more and 50/50 or less; and a method for producing the same. The liquid developer of the present invention is suitably used in development or the like of latent images formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

A liquid developer containing toner particles containing a resin and a basic dispersant in an insulating liquid, wherein the resin contains a polyester A having a furan ring. The liquid developer of the present invention is suitably used in development and the like of latent images formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.

A liquid developer containing toner particles containing a resin and a pigment, and an insulating liquid, the toner particles being dispersed in the insulating liquid, wherein the insulating liquid contains an olefin having 12 carbon atoms or more and 18 carbon atoms or less in an amount of 10% by mass or more. The liquid developer of the present invention can be suitably used in developing latent images formed in, for example, an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.

A method for producing a liquid developer containing toner particles containing a resin containing a polyester and a pigment, and an insulating liquid, wherein the toner particles are dispersed in the insulating liquid, including: step 1: melt-kneading the resin and the pigment, and pulverizing a melt-kneaded mixture to provide toner particles; step 2: dispersing the toner particles obtained in the step 1 in the insulating liquid in the presence of a basic dispersant to provide a dispersion of toner particles; and step 3: wet-milling the dispersion of toner particles obtained in the step 2 to provide a liquid developer, wherein the basic dispersant is an amide compound obtained by a reaction between a polyethyleneimine and a polyester (D) obtained by self-condensation of 12-hydroxystearic acid. The liquid developer obtained by the method of the present invention can be suitably used in development of latent images formed in, for example, an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.

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Wakayama, Japan

Tatsuya Yamada