Konica Minolta Business Technologies, Inc.

Konica Minolta, Inc.

Mikihiko Sukeno

Tatsuya Nagase

Tomomi Oshiba

Tomoko Mine

Saburou Hiraoka

Ken Ohmura

Hajime Tadokoro

Kenji Hayashi

Masahiro Anno

Chiaki Yamada

Hitomi Motani

Takanori Tanaka

Yoshiaki Kobayashi

Kosuke Nakamura

Tsuyoshi Uchida

Hiroyuki Kozuru

Yoshiyasu Matsumoto

Takanari Kayamori

Masaharu Shiraishi

Masaaki Oka

Yuya Iwagoe

Michiaki Ishikawa

A liquid developer includes an insulating liquid and toner particles which are dispersed in the insulating liquid and contain a resin and a coloring agent. The resin contains a first resin which is a crystalline urethane-modified polyester resin resulting from increase in chain length of a component derived from a polyester resin by a compound containing an isocyanate group. The toner particles have a peak in a DSC curve in temperature increase at 55&#xb0; C. or higher, have a peak in the DSC curve in temperature decrease at 30&#xb0; C. or higher, and have a storage elastic modulus at 80&#xb0; C., not lower than 1&#xd7;10Pa and not higher than 1&#xd7;10Pa.

Liquid developer

An electrostatic latent image developer of the present invention includes a resin, a colorant and a colorant dispersant, wherein the colorant dispersant contains a first polymer compound containing a constitutional unit derived from a monomer A, a constitutional unit derived from a monomer B and a constitutional unit derived from a monomer C, the monomer A is 4-vinylpyridine, the monomer B is CH&#x2550;CR&#x2014;COOR(where Rrepresents hydrogen or a methyl group; and Rrepresents an alkyl group having 1 to 10 carbon atoms), and the monomer C is CH&#x2550;CR&#x2014;COOR(where Rrepresents hydrogen or a methyl group; Rrepresents (CHCHO)CHor (CHCHO)CHCH; and n represents an integer of 12 to 18).

Electrostatic latent image developer

The toner for electrostatic image development has excellent charge properties, by which excellent toner particle size-controlling ability is achieved, and moreover the sharpening of a particle size distribution is achieved. The toner is composed of toner particles containing a binder resin. The process has an aggregating step of adding an aggregating agent containing a transition element into an aqueous medium of dispersed fine binder resin particles to aggregate the fine binder resin particles, and an aggregation-stopping step of adding an aggregation stopper composed on a sulfur atom-containing compound exhibiting a reducing action on the aggregating agent. The aggregating agent is a salt of a bivalent or higher metal selected from Sr, Ti, V, Cr, Mn, Fe, Co, Ni and Cu.

Production process of toner for electrostatic image development

A toner comprising toner particles containing a binder resin comprising a crystalline polyester resin, a non-crystalline polyester resin and an acryl resin having a cross-link structure, and the acryl resin having a cross-link structure has a cross-link site derived from a crosslinking agent represented by the following formula (1):CH&#x2550;CR&#x2014;C(&#x2550;O)O&#x2014;Z&#x2014;OC(&#x2550;O)&#x2014;CR&#x2550;CH&#x2003;&#x2003;Formula (1)wherein Rand Rare each a hydrogen atom or an alkyl group of 1 to 3 carbon atoms, and Z is a hydrocarbon group of 2 to 90 carbon atoms, provided that the hydrocarbon group may include an ether linkage, an ester linkage, a heterocyclic ring or a substituent.

Toner for electrostatic latent image development and production method thereof

Provided is a method of manufacturing toner by which the toner capable of forming high quality images and reproducing high density gradation, which exhibits an excellent high-temperature offsetting property together with excellent low-temperature fixability, and provides appropriate gloss with respect to images to be formed, can be stably prepared; and also provided is the toner. After conducting a step in which particles made of at least a crystalline polyester resin are coagulated to form core coagulated particles, and an unsaturated amorphous polyester resin particle is attached onto the surface of each of the core coagulated particles to form core-shell type coagulated particles, radical polymerization reaction is conducted by acting a radical polymerization initiator on the foregoing core-shell type coagulated particles to conduct a step in which a layer made of a crosslinking amorphous polyester resin is formed on the surface of each of the core coagulated particles.

Electrostatic charge image developing toner and method of manufacturing the same

A method of producing an electrostatic image developing toner comprising toner particles comprising a binder resin containing at least a non-crystalline polyester resin having a crosslinking structure and a crystalline polyester resin, the method comprising the steps of (a-1) preparing a crystalline polyester resin particle aqueous dispersion liquid; (a-2) preparing a polymerizable unsaturated non-crystalline polyester resin aqueous dispersion liquid; (b) preparing crosslinking non-crystalline polyester resin particles by adding a radical polymerization initiator to the aqueous dispersion liquid of particles containing the non-crystalline polyester resin having a polymerizable unsaturated bond; (c) preparing core particles by aggregating at least the particles containing the crystalline polyester resin in an aqueous medium; and (d) preparing a shell layer containing the non-crystalline polyester resin having a crosslinking structure by fusing the particles containing the non-crystalline polyester resin having a crosslinking structure on surfaces of the core particles in an aqueous medium.

Electrostatic image developing toner and producing method of the same

A two-component developer is disclosed, composing a toner comprising parent toner particles with an attached external additive and a carrier provided with a resin covering layer on a surface of a core particle, wherein the resin covering layer comprises a binder resin comprising an acrylic resin and when the resin covering layer is divided in half to a core particle side and a surface side, a nitrogen element content of the core particle side is larger than a nitrogen element content of the surface side.

Two-component developer

A method of producing a toner comprising toner particles containing a binder resin composed of a non-crystalline polyester resin having a crosslinked structure and a crystalline polyester resin is disclosed, the method comparing steps of;

Producing method of toner for developing static image

A toner bottle containing a cylindrical toner container having therein a toner comprising at least a resin, a colorant and an external additive, the toner container having a toner discharge port on an end thereof and a rotation axis along the cylindrical toner container, and the toner container being installable in an image forming apparatus, wherein the toner container has plural protrusions which are intermittently provided in an interior of the cylindrical container, the protrusions having a function to convey the toner toward the toner discharge port when the toner container is rotated around the rotation axis; an X-ray intensity ratio of titanium to silicon (Ti/Si) determined via X-ray fluorescence spectrometry of the toner is 1.0 to 3.0; and a conveyance index of the toner is 2.0 to 10.0 mg/sec.

Toner bottle for electrostatic latent image developing

Disclosed is an electrostatic charge image developing toner containing external additives possessing at least amorphous silica and a crystallized metal oxide selected from titanium oxide, aluminum oxide, zirconium oxide, or calcium oxide, wherein the amorphous silica is placed as a nucleus, and the crystallized metal oxide is present on the silica surface.

Electrostatic charge image developing toner

Disclosed is an electrostatic charge image developing toner containing external additives comprising at least amorphous silica and a crystallized metal oxide selected from titanium oxide, aluminum oxide, zirconium oxide, or calcium oxide, wherein the amorphous silica is present on the crystallized metal.

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Hyogo, Japan

Mikihiko Sukeno