Abstract: To provide a method for producing a toner, containing a milling step containing finely milling particles and classifying coarse particles by using at least a mill and a cyclone unit, and a classifying step containing classifying pulverized particles by using at least a classifier and a cyclone unit, wherein any of the pulverized particles and other particles, which are classified by the classifier in the classifying step and returned, are returned to the cyclone unit in the milling step, and a toner produced by the method for producing the toner.

Abstract: An air classifier contains a cylindrical casing provided with at an upper part thereof a feed port to feed high pressure air and a powder material, an umbrella-shaped center core in the casing, and an umbrella-shaped separator core arranged downstream of the center core in the casing and including an opening at center thereof. The air classifier has a configuration containing a dispersion chamber to disperse the powder material, being surrounded by an inner wall of the upper part casing and the center core, and a classification chamber to classify the powder material into fine and coarse powders by centrifugation, being surrounded by the center core, separator core and inner wall of the casing. In the dispersion chamber provided are a louver ring containing guide slats circularly arranged at regular intervals, and a space encircling the louver ring and serving as flow passage of the air and powder material.

Abstract: 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.

Abstract: A toner manufacturing process, includes: melting a kneaded composition, to thereby obtain a melted composition; and spraying the melted composition with a high pressure gas, to thereby form a fine particle. The kneaded composition is selected from the group consisting of the following <1>, <2> and <3>: <1> a first kneaded composition including a binder resin, a colorant, and a charge controlling agent, <2> a second kneaded composition including a binder resin, a colorant, a charge controlling agent, and a releasing agent, and <3> a third kneaded composition including a binder resin, a magnetic agent, a charge controlling agent, and a releasing agent.

Abstract: To provide an electrophotographic toner pulverizing apparatus and an electrophotographic toner pulverizing method for preventing reduction in wear resistance of a rotor, a stator, and the like even in long-term pulverizing of toner. The electrophotographic toner pulverizing apparatus according to the present invention has a pulverizing chamber with at least a rotor and a stator disposed therein. The surface of at least one of the rotor and the stator has a chromium plated layer having Cr as a main component and containing Mg, Al, Si, Ti, Mn, Fe, and C elements.

Abstract: A pulverization/classification apparatus includes a plurality of air nozzles, a milling chamber as a space for pulverizing particles by compressed air jetted by the air nozzles, and a rotor installed at an upper part of the milling chamber that classifies powder materials flowing into the rotor from the milling chamber with centrifuging into fine particles and coarse particles. The rotor includes plural blade members, and a width of the blade members within the rotor are set to be 1/50- 2/25 of the rotor's diameter.

Abstract: A toner includes toner particles which have a binder resin and a colorant. The toner has a weight average particle diameter of from 4 to 7 ?m and includes toner particles having a circle equivalent diameter of from 0.6 to 2.0 ?m in an amount not greater than 5% by quantity, toner particles having a particle diameter of from 3.17 to 4.00 ?m in an amount of from 10 to 40% by quantity, toner particles having a diameter of from 4.00 to 5.04 ?m in an amount of from 20 to 40% by quantity, and toner particles having a diameter not less than 12.7 ?m in an amount of from 0 to 1.0% by weight. The toner satisfies the following relationship: 1.04?D4/D1?1.30, wherein D4 represents the weight average particle diameter and D1 represents a number average particle diameter of the toner.

Abstract: To provide a method for producing a toner, containing a milling step containing finely milling particles and classifying coarse particles by using at least a mill and a cyclone unit, and a classifying step containing classifying pulverized particles by using at least a classifier and a cyclone unit, wherein any of the pulverized particles and other particles, which are classified by the classifier in the classifying step and returned, are returned to the cyclone unit in the milling step, and a toner produced by the method for producing the toner.

Abstract: A mixture including at least a binder resin and a colorant and a kneader configured to knead such a mixture. The mixture may include air bubbles having a density from 104 to 108 pieces/cm3 and constituting from 65 to 95% of said mixture by volume. The kneader may be configured to knead the mixture under pressure upon application of heat to the mixture to prepare a kneaded mixture.

Abstract: A fluidized bed pulverizing and classifying apparatus is disclosed having a vessel that includes a pulverizing section having a pulverizing nozzle spraying compressed air to pulverize a powder, a classifying section located over the pulverizing section, including a classifying rotor classifying the powder, and a fluidized bed. The vessel also contains a supply of secondary air.

Abstract: The present invention provides a method for manufacturing particles, where a viscous material is sprayed with a high-pressure gas for atomization while the viscous material is being discharged in a chamber, and cooling air is introduced in the chamber for granulation. The present invention also provides a method for manufacturing a toner, where a mixture containing at least a binding resin and a colorant is melt mixed under pressure or melt mixed with an injection of a supercritical fluid, the obtained melt-mixed substance is sprayed with a high-pressure gas for atomization while the melt-mixed substance is being discharged in a chamber, and cooling air is introduced in the chamber from an air inlet formed on the chamber.

Abstract: The present invention provides a classification apparatus which includes a hopper utiling a container with a vibrating unit allocated in a suspended state on the inner wall of the hopper and a classification means. It also provides a classification method by means of the classification apparatus.

Abstract: A fluidized bed pulverizing and classifying apparatus is disclosed having a vessel that includes a pulverizing section having a pulverizing nozzle spraying compressed air to pulverize a powder, a classifying section located over the pulverizing section, including a classifying rotor classifying the powder, and a fluidized bed. The vessel also contains a supply of secondary air.

Abstract: A fluidized bed pulverizing and classifying apparatus is disclosed having a vessel that includes a pulverizing section having a pulverizing nozzle spraying compressed air to pulverize a powder, a classifying section located over the pulverizing section, including a classifying rotor classifying the powder, and a fluidized bed. The vessel also contains a supply of secondary air.

Abstract: A toner classification device including a casing including at least one classification space. Each of classification includes a classification rotor and a toner discharging outlet. At least a portion of the surface of a part of the inner surface of the toner classification device which toner particles contact includes a blast-treated surface.

Abstract: A pulverization/classification apparatus includes a plurality of air nozzles, a milling chamber as a space for pulverizing particles by compressed air jetted by the air nozzles, and a rotor installed at an upper part of the milling chamber that classifies powder materials flowing into the rotor from the milling chamber with centrifuging into fine particles and coarse particles. The rotor includes plural blade members, and a width of the blade members within the rotor are set to be 1/50- 2/25 of the rotor's diameter.

Abstract: A toner includes toner particles which have a binder resin and a colorant. The toner has a weight average particle diameter of from 4 to 7 ?m and includes toner particles having a circle equivalent diameter of from 0.6 to 2.0 ?m in an amount not greater than 5% by quantity, toner particles having a particle diameter of from 3.17 to 4.00 ?m in an amount of from 10 to 40% by quantity, toner particles having a diameter of from 4.00 to 5.04 ?m in an amount of from 20 to 40% by quantity, and toner particles having a diameter not less than 12.7 ?m in an amount of from 0 to 1.0% by weight. The toner satisfies the following relationship: 1.04?D4/D1?1.30, wherein D4 represents the weight average particle diameter and D1 represents a number average particle diameter of the toner.

Abstract: A toner manufacturing process, includes: melting a kneaded composition, to thereby obtain a melted composition; and spraying the melted composition with a high pressure gas, to thereby form a fine particle. The kneaded composition is selected from the group consisting of the following <1>, <2> and <3>: <1> a first kneaded composition including a binder resin, a colorant, and a charge controlling agent, <2> a second kneaded composition including a binder resin, a colorant, a charge controlling agent, and a releasing agent, and <3> a third kneaded composition including a binder resin, a magnetic agent, a charge controlling agent, and a releasing agent.

Abstract: A method of producing a toner including at least a binder resin and a colorant. The method includes kneading a mixture including the binder resin and the colorant under pressure while injecting a supercritical fluid into the mixture upon application of heat to uniformly disperse the supercritical fluid in the mixture; depressurizing the mixture such that the mixture foams; cooling the mixture to prepare a kneaded mixture including air bubbles; and pulverizing the kneaded mixture.

Abstract: A fluidized bed pulverizing and classifying apparatus is disclosed having a vessel that includes a pulverizing section having a pulverizing nozzle spraying compressed air to pulverize a powder, a classifying section located over the pulverizing section, including a classifying rotor classifying the powder, and a fluidized bed. The vessel also contains a supply of secondary air.