Ricoh Company, Ltd.

Noboru Kuroda

Hiroshi Takahashi

Kenichi Uehara

Yasushi Nakamura

Masato Kobayashi

Yasuaki Iwamoto

Yohichiroh Watanabe

Keiko Shiraishi

Tomio Kondou

Kohki Katoh

Kohsuke Suzuki

Yoshihiro Sugiyama

Takahiro Kadota

Ryoichi Ito

Kazuyuki Matsui

Shigeru Emoto

Osamu Uchinokura

Kumi Hasegawa

Satoru Miyamoto

Tomoyuki Satoh

Masahiro Kawamoto

Yoshihiro Suguro

Nobutaka Kinoshita

Shohichi Sugimoto

Hideyuki Ueda

Masashi Miyakawa

Yasuyuki Sanui

Shoichi Sugiyama

Tamotsu Kajihara

Osamu Kouzu

Kifuku Takagi

Osamu Kohzu

A cyclone classifier for classifying a particulate material, including an outer cylinder having a waistless part and an inverted-cone part vertically connected to an underside of the waistless part, and an inner cylinder which includes an exhaust opening such that the inner cylinder has a position-adjustable bottom end.

Cyclone classifier, flash drying system using the cyclone classifier, and toner prepared by the flash drying system

A method of manufacturing a toner including dissolving or dispersing a toner component containing a colorant and a resin in an organic solvent to obtain a liquid solution or dispersion, continuously emulsifying and dispersing the liquid solution or dispersion in an aqueous medium containing a particulate dispersant to obtain emulsified primary particles, controlling cohesion and agglomeration of the emulsified primary particles and removing the organic solvent, such that the ratio (T/T) of the arithmetic mean accumulation time (T) of the emulsified primary particles obtained in the controlling step to the arithmetic mean accumulation time (T) of the emulsified primary particles obtained in the continuously emulsifying and dispersing step is from 1 to 5.

Method of manufacturing toner, the toner produced thereby, developer containing the toner and an image forming apparatus using the toner

A method for producing a toner including dissolving or dispersing a toner constituent mixture including a binder resin and a colorant in an organic solvent to prepare a toner constituent mixture liquid; dispersing the toner constituent mixture liquid in an aqueous medium including a particulate dispersant to prepare an emulsion; and removing the organic solvent from the emulsion while applying a shearing force to the emulsion. A toner manufactured by the method and having a spindle form while satisfying specific particle diameter relationships. An image forming apparatus using the toner. A toner packing method and device in which the toner is fluidized and pressurized to be fed from a fluidizing container to a toner container on which a gas-powder separation sieve is set to discharge air therefrom.

Toner, method for manufacturing the toner, method and device for packing the toner, and image forming apparatus using the toner

Master batch pigment, toner including the master batch pigment and method for manufacturing the toner

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 toner for developing an electrostatic image, including a binder, a coloring agent and a charge controlling agent. When that portion of the toner which has a particle diameter of 5.04 &mgr;m or less accounts for 15-60% of the total number N of the toner, that portion of the toner which provides a number average particle diameter of 4.0 to 4.5 &mgr;m has such a content C1% by weight of the charge controlling agent that gives a ratio of C1/CT of 1.00 to 1.10, where CT is a total amount, in terms of % by weight, of the charge controlling agent in the toner. When that portion of the toner which has a particle diameter of 5.04 &mgr;m or less accounts for 15% or less of the total number N, that portion of the toner which provides a number average particle diameter of 4.2 to 4.8 &mgr;m has such a content C2% by weight of the charge controlling agent that gives a ratio of C2/CT of 1.02 to 1.15.

Toner for developing electrostatic image and process of preparing same

A two-component developer includes a magnetic carrier including magnetic carrier particles with an average particle diameter of 35 &mgr;m to 100 &mgr;m, and a toner including toner particles with a weight-average particle diameter of 6.0 &mgr;m to 11.5 &mgr;m, to which at least one additive is externally added thereto in an amount of 0.3 to 1.5 wt. % to the toner, the toner particles including (a) toner particles with a particle diameter of 5 &mgr;m or less with a content ratio of 15% or less by number, and (b) toner particles with such a particle diameter that is two times or greater than the weight-average particle diameter of the toner particles with a content ratio of 5% or less by volume, the toner particles satisfying a relationship of 0.60&lE;D25/D75&lE;0.85 as defined in the specification. A container in which the two-component developer is contained, and an electrophotographic image formation apparatus in which the container is incorporated are proposed.

Two-component developer, two-component developer holding container, and electrophotographic image formation apparatus equipped with the container

A toner containing toner particles has a particular weight-average particle diameter, containing therein toner particles with another particle diameter in a predetermined number percentage of the number of the toner particles. A releasing agent contained in the toner particles has a particular endotherm ratio (Q/q), that is measured, using a differential scanning calorimeter (DSC), wherein q is the endotherm (&mgr;V&middot;min/mg) of the releasing agent contained in predetermined classified and sampled toner particles, assessed per unit amount of the sampled toner particles, and Q is the endotherm (&mgr;V&middot;min/mg) of the releasing agent contained in the toner particles of the toner in its entirety, assessed per unit amount of the toner particles. A method of producing the toner, and a method of forming images, using the toner, and a toner container or cartridge containing therein the toner are disclosed.

Toner, method of producing the toner, image formation method using the toner, and toner container

A toner is made or toner particles which contains a binder resin and a coloring agent, wherein the toner particles have a weight-average particle size in a range of 6.0 to 11.5 &mgr;m, and contains toner particles (a) with a particle diameter of 5 &mgr;m or less in a content ratio of 1 to 15% by number, and toner particles (b) with a particle diameter of twice or more the weight-average particle size in a content ratio of 5 wt % or less, and the number-average particle size D25 and the number-average particle size D75 respectively obtained when the cumulative number of the toner particles reaches 25% and 75% at the measurement of a cumulative toner particle distribution by number thereof are in the relationship of 0.60&lE;D25/D75&lE;0.95. A two-component developer includes the above-mentioned toner and a carrier.

Toner and two-component developer for electrophotographic process and image formation method and image formation apparatus using the toner

A multi-color toner set includes a plurality of color toners with different colors, each color toner including toner particles, each toner particle including a binder resin, a pigment and a releasing agent, at least part of the releasing agent being present in the form of domains in the binder resin, with a difference between a maximum content and a minimum content of the releasing agent in the form of domains in the binder resin in each of the color toners being in a range of 20% or less. Multi-color images can be formed, using this multi-color toner set.

Multi-color toner set and method of forming multi-color images, using the multi-color toner set

A toner for developing electrostatic latent images which includes at least a binder resin, a colorant and a releasing agent, wherein the releasing agent includes a particulate material capable of absorbing the releasing agent. The particulate material preferably has an absorption rate not less than about 10% by weight in a combination with the releasing agent.

Toner for developing electrostatic latent image

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Izunokuni, Japan

Noboru Kuroda