Ricoh Company, Ltd.

Satoru Miyamoto

Hiroshi Yaguchi

Nobutaka Kinoshita

Masami Tomita

Emi Kita

Yasuo Asahina

Makoto Yasuda

Tomomi Suzuki

Junichi Terai

Mugijirou Uno

Keiko Matsumoto

Yoshihiro Suguro

Maiko Koeda

Kiyonori Tsuda

Yasuaki Iwamoto

Koichi Sakata

Mitsuo Aoki

Osamu Uchinokura

Hiroyuki Fushimi

Maiko Kondo

Nobuyasu Makino

Kumi Hasegawa

Tetsuya Tanaka

Noboru Kuroda

Shohichi Sugimoto

Yasushi Nakamura

Hideyuki Ueda

Mutsumi Takahashi

Tamotsu Kajihara

Shinji Hirata

Tomio Kondo

A method for loading a replenishment developer into a developer accommodating container such that when the replenishment of the replenishment developer inside the loaded developer accommodating container is started, the developer composed of a toner and a carrier, or a toner is discharged from a developer discharge port of the developer accommodating container, wherein when a premix toner that is a replenishment developer composed of a replenishment toner and a replenishment carrier is loaded into a toner bottle serving as the developer accommodating container, the replenishment carrier is loaded and then the replenishment toner is loaded.

Developer loading method, loaded developer accommodating container, developer replenishment device, and image forming apparatus

A developing agent storage device for storing a refill developing agent includes toner particles, carrier particles, an inner layer of the developing agent storage device. The toner particles and carrier particles compose the refill developing agent. The inner layer is provided as a wall contacting the refill developing agent. An electrostatic chargeability level of the toner particles, the carrier particles, and the inner layer is set in an order of toner, inner layer, and carrier from any one of a negative charge side and a positive charge side.

Developing agent storage device and image forming apparatus having same in which the chargeability level of the toner, storage device, and carrier have a specific relationship

A conveying device includes a guiding member that has a contact portion that comes into contact with an inner peripheral surface of a conveying belt in which a plurality of suction holes is formed, and an endless conveying belt that has ridges to hold a recording medium lest the recording medium come into contact with the suction holes. A plurality of slits is formed in the contact portion to attract the recording medium to the endless conveying belt through the suction holes. The slits are formed to prevent the conveying belt from falling in the slits when the conveying belt is pressed due to suction.

Conveying device and image forming apparatus

A developing device and image forming apparatus that can satisfy stability over time in relation to amount of developer carried, and prevent developer retention, deterioration of developer and developing sleeve adhesion, wherein the amount of developer carried per unit area on the developer carrier in the developing region is 30 mg/cmto 60 mg/cm; the weight mean particle diameter of the toner is 4.5 &#x3bc;m to 8.0 &#x3bc;m; the ratio Dw/Dn of the toner weight mean particle diameter (Dw) and the number mean particle diameter (Dn) is 1.20 or less; an irregular roughness pattern having the maximum height Rz of the surface roughness of 20 to 40 &#x3bc;m and the mean space Sm of the roughness of 100 to 200 &#x3bc;m is formed on the surface of the developer carrier; and the relationship between the developing gap PG and the gap DG between the developer restricting member and the developer carrier is 1.0&#x2266;(DG/PG)&#x2266;3.0.

Developing device and image forming apparatus comprising the same

A pulverization/classification apparatus including a cylindrical vessel having an inner wall, on a surface of which a layer including a release agent is located; a pulverizer configured to pulverize a material such as toner raw materials in the cylindrical vessel using a compressed air to prepare a particulate material; and a classifier configured to classify the particulate toner material to prepare a powder of the material. Alternatively, the inner wall of the cylindrical vessel has a circumferentially projected portion. A method for manufacturing a powder such as toners using the pulverization/classification apparatus is also provided.

Pulverization/classification apparatus for manufacturing powder, and method for manufacturing powder using the pulverization/classification apparatus

In a developing device of the present invention, the ratio of the volume of a two-ingredient type developer to the capacity of a space storing the developer is selected to range from 40% to 75%. A carrier, forming part of the developer, is made up of a core and a resinous coating layer formed on the core. The resinous coating layer contains conductive particles each having a tin dioxide layer formed on a core and an indium oxide layer formed on the tin dioxide layer and containing tin dioxide. The conductive particles are provided with an oil absorbing amount ranging from 10 ml/100 g to 300 ml/100 g.

Developing device, process cartridge and image forming apparatus including the same

An image forming apparatus and process cartridge that achieves extended operating life of a two-component developer without generating such problems as toner scattering, etc. either in the initial period or over time. The gap between the image support member and the developer support member is set to 0.3&#xb1;0.1 mm. A substance having a resin cover layer on the surface of a core material is used as the carrier. The resin cover layer provides a conductive covering layer having a tin dioxide layer on the surface of base particles and an indium oxide layer, and contains conductive particles formed such that the oil adsorption is 10 to 300 mL/100 g. A substance that provides a bonding resin including a hybrid resin having vinyl polymers and polyester polymers is used as the toner. The amount of hybrid resin contained in relation to the amount of releasing agent is set to the range of 0.5 to 3.

Image forming apparatus and process cartridge for use therewith

A full color image forming method including the steps of developing an electrostatic latent image formed on an image bearing member with a color toner to form a color toner image thereon; first transferring the color developer including a color toner image onto an endless intermediate transfer material while applying a developing bias thereto; repeating the above-mentioned steps a plurality of times using a plurality of different color developers to form a full color toner image on the intermediate transfer material; and second transferring the full color image onto a receiving material, wherein a weight of each of the color toner images formed on the image bearing member is from about 0.4 mg/cm to about 1.5 mg/cm , and each of the color developers has a charge quantity not less than 15 &mgr;C/g in an absolute value, and wherein the following relationship is satisfied with respect to each of the first color toner transferring steps: 5.4&times;Q &plus;90<Vb&minus;V <5.4&times;Q &plus;150, wherein Vb represents the developing bias voltage (V), V represents a potential (V) of a background area of the electrostatic latent image, on which the color toner image is not to be formed, and Q is the charge quantity (&mgr;C/g) of the color developer.

Full color image forming method, and toner and intermediate transfer material for the method

A full color image forming method including the steps of developing an electrostatic latent image formed on an image bearing member with a color toner to form a color toner image thereon; first transferring the color developer including a color toner image onto an endless intermediate transfer material while applying a developing bias thereto; repeating the above-mentioned steps a plurality of times using a plurality of different color developers to form a full color toner image on the intermediate transfer material; and second transferring the full color image onto a receiving material, wherein a weight of each of the color toner images formed on the image bearing member is from about 0.4 mg/cm to about 1.5 mg/cm , and each of the color developers has a charge quantity not less than 15 &mgr;C/g in an absolute value, and wherein the following relationship is satisfied with respect to each of the first color toner transferring steps: 5.4&times;Q1&plus;90<Vb&minus;V1<5.4&times;Q1&plus;150, wherein Vb represents the developing bias voltage (V), V1 represents a potential (V) of a background area of the electrostatic latent image, on which the color toner image is not to be formed, and Q1 is the charge quantity (&mgr;C/g) of the color developer.

A toner including toner particles including at least a binder resin having a first melting point and a first solubility parameter, a colorant and a particulate release agent having a second melting point lower than the first melting point and a second solubility parameter different from the first solubility parameter, wherein the particulate release agent dispersed in the toner particles has an average needle-shape degree LD/SD of not less than 1.6, where LD is a diameter of a particle of the release agent dispersed in the toner in a major axis direction thereof and SD is a diameter of the particle in a minor axis direction.

Electrophotographic toner and image forming method using the toner

A color toner comprises a binder resin, a coloring agent, a release agent and a charge controlling agent, wherein the release agent dispersed in the binder resin has an average particle diameter of from about 0.1 to about 2 &mgr;m and wherein a fixed color toner image, which is developed and fixed using the toner, has a Haze factor less than about 20% when the image has an image density of 1.5. The color toner produces images having good image qualities such as good color reproducibility.

Color toner and manufacturing method thereof and image forming method using the color toner

A color toner comprises a binder resin, a coloring agent, a release agent and a charge controlling agent, wherein the release agent dispersed in the binder resin has an average particle diameter of from about 0.1 to about 2 .mu.m and wherein a fixed color toner image, which is developed and fixed using the toner, has a Haze factor less than about 20% when the image has an image density of 1.5. The color toner produces images having good image qualities such as good color reproducibility.

Color toner and manufacturing method thereof and image forming method

An apparatus for pulverizing solid particles including an impact-type pulverizing device, a mechanical-type pulverizing device and a piping system connected to the pulverizing devices such that the solid particles may be selectively pulverized in the impact-type pulverizing device and in the mechanical-type pulverizing device successively in this or reverse order.

Pulverizing apparatus

A yellow toner for full-color electrophotography is made of yellow toner particles, each toner particle containing a binder resin and C.I. Pigment Yellow 62 and/or C.I. Pigment Yellow 168 as a yellow coloring agent. The above-mentioned yellow toner is used in combination with a carrier to prepare a two-component yellow developer.

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Kanagawa, Japan

Satoru Miyamoto