Sharp Kabushiki Kaisha Corporation

Yoritaka Tsubaki

Keiichi Kikawa

Yoshitaka Kawase

Yoshiaki Akazawa

Takashi Hara

Yoshinori Mutoh

Yasuhiro Shibai

Yasuo Imura

Tadayuki Sawai

Keigo Mitamura

Osamu Wada

Shintaro Fukuoka

Yui Kawano

Atsushi Ide

Hiroshi Onda

Saori Yamada

Takeshi Katoh

Yuya Kondo

Hideo Matsuda

Satoru Ariyoshi

Masao Yamamoto

Tadanori Kano

Kazumi Irie

Hiroki Maeda

Shoji Nakai

Maiko Nagaoka

The peak top molecular weight of the tetrahydrofuran-soluble component of the toner, as measured by gel permeation chromatography, is 4,000 or more and 6,500 or less. The tetrahydrofuran-insoluble component of the toner is 10% by weight or more and 30% by weight or less. When the endothermic peak temperature T1 in the heating process and the exothermic peak temperature T2 during the cooling process originating from the ester wax is measured using a differential scanning calorimeter, the value T1-T2 is 15° C. or more and 30° C. or less.

Toner and two-component developer

A two-component developerincludes a carrierand a toner. The carriersatisfies the relationships 100&#x2264;&#x3b1;&#x2264;220 and 300&#x2264;&#x3b2;&#x2264;480 when a voltage is applied in 1 V steps by a bridge resistance measurement method, where &#x3b1; (V) is a carrier voltage value obtained when a current value flowing through the carrierreaches 1.0(A), and &#x3b2; (V) is a carrier voltage value obtained when the current value reaches 1.0(A).

Two-component developer, developing device, and image forming device

A toner contains at least a crystalline polyester resin and an amorphous linear polyester resin that uses diethylene glycol as an alcohol component, and a monoester wax and a montan ester wax as release agent components, wherein 6&#x2264;&#x3b1;&#x2264;8 and 14&#x2264;mw/&#x3b1;&#x3c;30 are satisfied, where &#x3b1; represents an amount of the crystalline polyester resin added relative to 100 parts by weight of the amorphous linear polyester resin and mw represents an amount of the montan ester wax added.

Toner, two-component developer, and method for producing toner

The toner including a crystalline polyester resin dispersed in an amorphous polyester resin obtained by polymerizing a bivalent alcohol component and a dicarboxylic component, the crystalline polyester resin containing a linear saturated aliphatic polyester unit and being dispersed by a monoester-based wax added as a detaching agent, wherein the crystalline polyester resin in the toner has a dispersion diameter of 100 nm or more and 500 nm or less, and the monoester-based wax has a dispersion diameter of 200 nm or more and 1,000 nm or less.

Toner

Toner of one aspect of the present invention has a weight average molecular weight Mw of 30,000&#x2266;Mw&#x2266;95,263 as determined from a molecular weight distribution based on GPC, includes a THF-insoluble gel component at a weight proportion of less than 5%, and includes components each having a molecular weight of 500 to 1500 which components have an area occupancy of 4% to 10% on a chart of the molecular weight distribution based on GPC.

Method for producing ground toner

A two-component color developer containing a toner and a resin-coated carrier, the toner containing at least a polyester resin as a binding resin, an organic pigment as a colorant and inorganic fine particles as an external additive, wherein the inorganic fine particles have a negative polarity, the toner has a volume resistivity of 40&#xd7;10to 220&#xd7;10&#x3a9;cm and a negative polarity, and the carrier has a coat durability of 90% or greater.

Two-component color developer and image formation device using same

Toners of respective colors of a full-color toner set each contain a binder resin which is polyester resin; and a release agent dispersing aid which is styrene acrylic copolymer resin having at least one of an &#x3b1;-methylstyrene structure and a styrene structure. The styrene acrylic copolymer resin is contained in an amount of 7 parts by weight to 14 parts by weight with respect to 100 parts by weight of the polyester resin. The full-color toner set has a sum of resistivities of the toners of the respective colors of 410&#xd7;10to 510&#xd7;10(&#x3a9;&#xb7;cm).

Full-color toner set, full-color developer set, image-formation method using same, and image-formation device

A method for manufacturing a capsule toner having improved preservability with no deterioration in low-temperature fixability is provided. The method for manufacturing a capsule toner includes a mixed fine resin particle adhering step of adhering mixed fine resin particles including crystalline polyester fine resin particles and amorphous fine resin particles to surfaces of toner base particles to form mixed fine resin particle-adhered particles, a spraying step of spraying a mixed solution of a liquid for plasticizing the toner base particles and the mixed fine resin particles and a crystal nucleating agent, while fluidizing the mixed fine resin particle-adhered particles, and a film-forming step of making a film of the mixed fine resin particles by impact force so that the film is a resin coating layer on the surfaces of the toner base particles.

Method for manufacturing capsule toner

There are provided a capsule toner, a two-component developer, and a capsule toner manufacturing method. The capsule toner in which a resin coating layer made of fine release-agent particles and fine resin particles is made on the surfaces of toner base particles, and thus excellent offset resistance without impairing blocking resistance can be obtained. The capsule toner includes toner base particles containing a binder resin and a colorant, and a resin coating layer made of fine release-agent particles and fine resin particles, for covering the surfaces of the toner base particles. The fine release-agent particles are dispersed in the resin coating layer.

Capsule toner, method of manufacturing the same, and two-component developer

A capsule toner capable of enhancing low temperature fixation property without impairing preservation property under a high temperature environment, a two-component developer, and an image forming apparatus are provided. The capsule toner is constituted of toner particles having toner base particles and a coating layer for coating the surface thereof. The toner base particle includes styrene-acrylic resin or polyester resin as a binder resin, and the coating layer includes styrene-acrylic resin or polyester resin. The capsule toner contains 0.05% by weight or more and 0.70% by weight or less of volatile plasticizer based on a total amount of the capsule toner.

Capsule toner, two-component developer, and image forming apparatus

A method for manufacturing a capsule toner, capable of obtaining a capsule toner including a coating layer having uniform thickness at high yield is provided. The method for manufacturing a capsule toner includes a fine resin particle adhering step of adhering fine resin particles to surfaces of toner base particles, a spraying step of spraying a spray liquid for plasticizing the toner base particles and the fine resin particles, while fluidizing the toner base particles and the fine resin particles, and a film-forming step of fluidizing the toner base particles and the fine resin particles until the fine resin particles adhered to the surfaces of the toner base particles are softened to form a film. In the spraying step, ultrasonic vibration is applied to set a number average liquid-droplet diameter of the spray liquid to less than 10 &#x3bc;m.

A toner manufacturing method is provided. The toner manufacturing method includes a step of adhering fine resin particles whose volume average particle size is 5% or more and 17% or less of a volume average particle size of toner base particles, to surfaces of the toner base particles; and a step of plasticizing the toner base particles and the fine resin particles by adding mechanical impact thereto while spraying lower alcohol, and fusing the fine resin particles to the surfaces of the toner base particles to form a plurality of projections of the fine resin particles, on the surfaces of the toner base particles. Surface coverage of the surfaces of the toner base particles with the projections is 10% or more and 50% or less.

Toner manufacturing method

There is provided a toner which can be manufactured in a simple production method and which is excellent in preservation stability and anti-offset property with uniformly-charging performance. The toner is formed of aggregate of resin-containing particles which are obtained by forming amorphous resin particles into slurry and further finely granulating the amorphous resin particles in form of the slurry followed by aggregation of the amorphous resin particles and which contains a binder resin, a colorant, a release agent, and a release agent-dispersing aid, the resin-containing particles having a volume average particle diameter in a range of from 0.4 &#x3bc;m to 1.0 &#x3bc;m.

Toner and method of manufacturing the same

A manufacturing apparatus provided with a rotary stirring section and a powder passage is used to manufacture the resin-layer coated carrier. At a fine resin particle adhering step, a magnetic base particle and a fine resin particle are inputted into the powder passage with the rotary stirring section rotating and the fine resin particle is adhered onto the surface of the magnetic base particle. At a spraying step, at least a liquid that plasticizes the fine resin particles is sprayed with spray gas from a spraying section on the magnetic base particle and the fine resin particle which are in a fluidized state in the powder passage. At a film-forming step, rotation by the rotary stirring section is continued to fluidize the magnetic base particles and the fine resin particles until the fine resin particles adhered to the magnetic base particles are softened to form a film.

Method of manufacturing resin-layer coated carrier, resin-layer coated carrier, developer, developing device, and image forming apparatus

A capsule toner achieving both low temperature fixability and hot offset resistance, and a method of manufacturing the capsule toner are provided. A capsule toner includes a toner base particle containing a binder resin and a colorant, and a resin coating layer formed on a surface of the toner base particle. The resin coating layer includes a film of plural fine resin particles having different complex viscosities. The plural fine resin particles include first fine resin particles having complex viscosity at a softening temperature of the toner base particles of 5.0&#xd7;10Pa&#xb7;s or more and 1.0&#xd7;10Pa&#xb7;s or less, and second fine resin particles having complex viscosity at a softening temperature of the toner base particles of 1.0&#xd7;10Pa&#xb7;s or more and 1.0&#xd7;10Pa&#xb7;s or less.

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Osaka, Japan

Yoritaka Tsubaki