Abstract: A process for disintegrating an agglomerated mass of silica fine powder comprises introducing the silica fine powder into an impact portion defined by either a rotatory strip and a fixed strip or two rotatory strips, and having a gap therebetween of 0.5 to 10 mm and mechanically impacting the silica fine powder by at the impact portion to disintegrate the agglomerated mass.

Abstract: A separator for classifying powder with air current, comprises a powder feed pipe and a classifying chamber, provided in said separator; a guide chamber provided at the upper part of said classifying chamber to communicate with said powder feed pipe; a plurality of introducing louvers provided between said guide chamber and said classifying chamber, at which the powder is flowed in from said guide chamber to said classifying chamber through the openings between said introducing louvers together with carrying air; an inclined classifying plate raised at its central part, provided at the bottom of said classifying chamber; classifying louvers provided along the side wall of said classifying chamber, through the openings of which the air is flowed to produce a whirling stream by which said powder fed into said classifying chamber together with carrying air is centrifugally separated into fine powder and coarse powder; a discharge opening provide at the central part of said classifying plate and from which the cl

Abstract: A toner for producing electrostatic latent images is produced by smoothing classified resinous particles so that the ratio of the smallest diameter to the largest diameter thereof is 0.70-0.90, mixing the smoothed base particles (A) with modifier particles (B) to attach the modifier particles (B) to the surfaces of the base particles (A), and fixing the modifier particles (B) to the base particles (A) under the action of a mechanical impact force.

Abstract: A toner for producing electrostatic latent images is produced by classifying a pulverized feed material into a coarse powder and a fine powder in a first classifying means, pulverizing and recycling the coarse powder to the first classifying means, introducing the fine powder into a multi-division classifying chamber divided into at least three sections where the fine powder is classified into at least a coarse powder fraction, a medium powder fraction and a fine powder fraction. The medium powder fraction is recovered to provide a toner. The coarse powder fraction is recycled to the first classifying means.

Abstract: A toner for developing electrostatic latent images is produced by a process comprising the steps of: (a) stirring at least water, hardly water-soluble inorganic fine powder and a specific compound thereby to prepare an aqueous dispersion medium; (b) adding a polymerizable monomer composition comprising at least a polymerizable monomer and a polymerization initiator to the aqueous dispersion medium; (c) forming particles of the polymerizable monomer composition in the aquoeus dispersion medium; (d) subjecting the particles of the polymerizable monomer composition to suspension polymerization, thereby to produce toner particles; and (e) removing the hardly water-soluble inorganic fine powder attached to the surfaces of the toner particles by an aqueous alkaline or acidic solution.

Abstract: A process for classifying toner particles supplied through a supply nozzle into at least three fractions in a classifying chamber divided into at least three sections and placed under a reduced pressure under the action of the inertia force of the toner particles supplied together with a gas stream and the centrifugal force of the curved gas stream due to Coanda effect. A first gas introduction pipe and a second gas introduction pipe are disposed above the classifying chamber so as to provide a first inlet and a second inlet opening with the first inlet being disposed closer to the supply nozzle than the second inlet. The absolute values of the static pressures P.sub.1 and P.sub.2 in the first and second gas introduction pipes are controlled so as to satisfy the relations of: .vertline.P.sub.1 .vertline..gtoreq.150 mm.aq., .vertline.P.sub.2 .vertline..gtoreq.40 mm.aq. and .vertline.P.sub.1 .vertline.-.vertline.P.sub.2 .vertline..gtoreq.100 mm.aq.

Abstract: A process for producing toner particles for developing electrostatic latent images, comprising the steps of introducing colored solid particles containing a binder resin into a multi-division classifying zone divided into at least three sections by partitioning means, so that the particles are fallen along curved lines; collecting a coarse powder consisting primarily of coarse particles in a first divided section, a medium powder consisting primarily of particles having a particle size within a defined range in a second divided section and a fine powder consisting primarily of particles having a particle size smaller than the defined range in a third divided section; feeding the classified coarse powder to a pulverizing step; and introducing the pulverized powder into the multi-division classifying zone. An apparatus for practicing the process is also disclosed.