Abstract: A toner for developing an electrostatic latent image, a process for producing the same, and a developer for developing an electrostatic latent image using the same are provided, in which the toner flowability, the charging property, the developing property, the transferring property and the fixing property are simultaneously satisfied in a long period of time. The toner for developing an electrostatic latent image comprising a colored particles containing a binder resin, a coloring agent and a releasing agent, and an external additive, the external additive containing a monodisperse spherical inorganic oxide having a true specific gravity of from 1.3 to 1.9 and a volume average particle diameter of from 80 to 300 nm. It is preferred that the inorganic oxide is silica, the colored particles have a shape coefficient of 125 or less, and the external additive further contains a reaction product of metatitanic acid and a coupling agent, which has an electric resistance of 1010 &OHgr;·cm or more.

Abstract: A toner including a resin and a colorant which is dispersed in the toner and which has an average major particle diameter not greater than about 0.5 &mgr;m, wherein the following relationships are satisfied: Ta≦100 (° C.), and (Tb−Ta)≧7.0 (° C.), wherein Ta represents a temperature at which the toner has a melt viscosity of 50,000 Pa·sec and Tb represents a temperature at which the toner has a melt viscosity of 5,000 Pa·sec.

Abstract: A cylindrical electrophotographic photoreceptor is disclosed. The layer thickness decreasing amount &Dgr;Hd (in &mgr;m) is 0≦&Dgr;Hd<5×10−6 per rotatio,n and residual potential variation amount per cm2 is 0≦&Dgr;Vr<100 (in V) for 1 A of an electric current generated by charging and exposure.

Abstract: A toner for electrophotography is disclosed. The resin binder is obtained by fusing fine resin particles comprising a crystalline material and amorphous polymer in a water-based medium. The crystalline material preferably has a melting point of 60 to 130° C., a number average molecular weight of 1,500 to 15,000, and a melt viscosity at the melting point +20° C. of not more than 100 Pa·s, and the amorphous polymer is preferably composed of a radically polymerizable monomer.

Abstract: 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.

Abstract: A process for forming toner particles includes aggregating the toner particles by adding an aggregating agent to a latex emulsion of resin having a colorant mixed therein, the adding being done under adding conditions of agitation and a temperature above a glass transition temperature of the resin, wherein the adding of the aggregating agent comprises first introducing at least about 40% by weight of a total amount of aggregating agent to be added at a rapid introduction rate and subsequently adding a remaining portion of the aggregating agent at a continuous addition rate slower than the rapid introduction rate. The particles are subsequently cooled to a temperature below the glass transition temperature of the resin when particles have been grown to the desired size.

Abstract: An electrophotographic photoreceptor having a bipolar charge transport layer with a hole-transporting property and an electron-transporting property, the bipolar charge transport layer containing a block copolymer or a graft copolymer, and a process cartridge and an electrophotographic apparatus using the electrophotographic photoreceptor. The electrophotographic photoreceptor has a high performance and a long life and can provide various properties required for a photoreceptor by forming, the bipolar charge transport layer which is excellent in hole- and electron-transporting properties, mechanical strengths, a discharge product resistance and a coating dispersion stability, and the process cartridge and the electrophotographic apparatus using the electrophotographic photoreceptor can provide a high performance and a high durability.

Abstract: A dry toner of polymerization type for electronic photography for forming an image on a recordable medium is synthesized during a polymerization process by adding a hydrophobic silica system compound having both hydrophobic groups and hydrophilic groups and having the following chemical structure formula: the silica system compound being a stabilizer in a polymerization composition.

Abstract: An apparatus including: a grinder adapted to grind toner particles; a classifier in communication with the grinder adapted to separate sized toner particles from unsized toner particles; a conduit in communication with the classifier which conduit is adapted to convey the sized toner particles away from the grinder; a heater adapted to heat and smooth the surface of the sized toner particles received from the conduit; and a particle separator adapted separate the resulting mixture of smooth surface toner particles and debris particles received from the heater.

Abstract: A full color electrophotographic toner including toner particles containing at least a binder resin, a colorant and a wax, and external additives, at least one of the external additives being rutile titanium oxide having a volume resistivity of 1×1014 to 1×1018 &OHgr;cm, and a dispersion absolute deviation a of rutile titanium oxide being 0.17 or less, and a full color electrophotographic developer and an image forming method using the same are provided. In the full color electrophotographic toner, the full color electrophotographic developer and the image forming method of the invention, a retransfer phenomenon of the transferred toner can be prevented, a chargeability and a transferability are not problematic at all, a charging amount of the toner in long-term use can be rendered appropriate and stable, and a fluidity is also excellent.

Abstract: A non-magnetic mono-component toner includes a toner and barium titanate having a surface area of 0.5 to 3 m2/g as measured in accordance with a BET method in an amount of 0.2 to 5 parts by weight per 100 parts by weight of the toner. The toner can form images of a high density and suppress fog in the background simultaneously.

Abstract: This invention pertains to an electrographic photosensitive material comprising a blocking layer, an electroconductive substrate layer and a charge generation layer, where the blocking layer comprises TiO2 with an average particle size less than about 50 nm and a quaternary ammonium salt, and where the quaternary ammonium salt is uniformly distributed in the blocking layer and is less than about 5 wt % of the blocking layer. In another aspect, this invention pertains to an image forming apparatus for forming images on a recording medium comprising an imaging light having a wavelength and an organic photoreceptor having a blocking layer, an electroconductive substrate layer, and a charge generation layer, where the blocking layer comprises TiO2 particles and a quaternary ammonium salt, and where the quaternary ammonium salt is uniformly distributed in the blocking layer and is less than about 5 wt % of the blocking layer.

Abstract: A developing material is obtained by performing melting and kneading steps, and then a milling step, for a particulate binder resin material having an average particle size of 250 to 600 &mgr;m and a magnetic powder having an apparent bulk density of 0.3 g/cm3 or more and a compacted bulk density of 2.5 g/cm3 or less.

Abstract: A developing agent comprising a toner particle containing a magnetic powder and a binder resin, the kinetic resistance of the developing agent being not higher than 200 M&OHgr;, and the absolute value of the difference &Dgr;V between the maximum value and the minimum value of the surface potential of the developing agent layer on a developing sleeve being not larger than 5V, is used for obtaining satisfactory developing agent image high in image density and low in fogging.

Abstract: A honing means produces sonic waves that suspend and propel a honing medium against a surface of a substrate. The honing medium impinges on the surface of the substrate and alters the substrate's surface roughness. The substrate and the honing means are positioned relative to each other to ensure substantial surface roughness uniformity.

Abstract: An electrophotographic imaging member with a charge generation section having separate layers of benzimidazole perylene photoconductive pigment and hydroxygallium ptalocyanine photoconductive pigment.

Abstract: A method for drying a porous solid saturated with a fluid including the steps of subjecting the saturate porous image to an ultrasonic signal to release the fluid from the saturated porous image layer; removing the fluid from said saturated porous solid, said subjecting step includes applying a predefined acoustic slow wave frequency based upon the particle sizes in said porous image layer thereby causing the fluid to move from an interior of said porous particulate image to an outer surface of said porous image, where fluid can be removed by conventional image.

Abstract: A solid freeform fabrication method and related apparatus for fabricating a three-dimensional object from successive layers of a primary body-building powder material and a binder powder in accordance with a computer-aided design of the object, the method including: (a) providing a work surface; (b) feeding a first layer of the primary body-building powder material to the work surface; (c) operating an electrophotographic powder deposition device to create a binder powder image in accordance with this design; (d) transferring this binder powder image to the first layer of body-building powder; (e) applying energy sources to fuse the binder powder, forming a binder fluid to permeate through the first layer of body-building powder for bonding and consolidating the powder particles to form a first cross-section of the object; (f) feeding a second layer of the primary body-building powder onto the first layer and repeating the operating, transferring, and applying steps to form a second cross-section of the objec

Abstract: Added to magnetic toner particles are 0.5 to 5% by weight based on the total weight of the toner particles of a magnetic powder and 0.01 to 0.5% by weight based on the total weight of the toner particles of stearate particles having an average particle diameter of 1 &mgr;m to 5 &mgr;m.

Abstract: A printing plate useful in lithographic printing is prepared by the process comprising: (a) applying an alkali soluble composition comprising at least one polymer composition to a hydrophilic surface on a substrate to provide the surface face with at least one layer which is alkali soluble at a pH in the range of about 6.0 to 14.0; (b) imaging the coated substrate electrostatically with a toner composition; (c) heating the imaged substrate a first time to a temperature greater than the glass transition temperature of the toner composition; (d) contacting the imaged substrate with an aqueous alkaline solution having a pH in the range of about 6.0 to about 14.0; and (e) heating the imaged substrate a second time to a temperature greater than the glass transition temperature of the toner composition. This printing plate is capable of long runs on press with good image quality and advantageously minimizes the occurrence of undesirable background toner “specking” on press.