Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer comprises a cured phenolic resin and a charge-transporting compound having at least one group selected from the group consisting of hydroxyalkyl groups, hydroxyalkoxy groups and hydroxyphenyl groups capable of having a substituent.

Abstract: A toner for developing an electronic latent image, including toner particles containing a binder resin and a colorant, and an external additive, is provided. The external additive contains silica formed by a sol-gel method of which the surface is subjected to hydrophobic treatment and which has an average primary particle size of 80 to 300 nm, a water content of 3 to 15% and a volume resistivity of 1×1013 &OHgr;cm or more. The invention further provides an image forming method and an image forming apparatus using the same. The toner for developing an electrostatic latent image is good in transferability over a long period of time and gives a high image quality without causing an image defect.

Abstract: A two-component developer comprises a toner which contains at least a resin and a colorant and to which an external additive is added, and a carrier. The toner has a number average molecular weight (Mn) not greater than 3,000 and contains particles having a molecular weight not greater than 1,000 in an amount not less than 40 number %. The carrier satisfies the relation 3,000,000≦&sgr;1000×Dc3≦20,000,00  (1) where &sgr;1000 represents a magnetization (emu/g) of the carrier at 1,000 oersted, and Dc represents a volume average particle diameter (&mgr;m) of the carrier.

Abstract: A process involving, for example, providing or generating an emulsion latex comprised of sodio sulfonated polyester resin particles by adding with shearing to the latex a colorant dispersion comprising from about 20 to about 50 percent of a predispersed colorant in water, followed by the addition of an organic or an inorganic acid; heating the resulting mixture at a temperature of from about 45° C. to about 65° C. followed by the addition of an water insoluble metal salt or water insoluble metal oxide thereby releasing metal ions and permitting aggregation and coalescence, resulting in toner particles; and optionally cooling the mixture and isolating the product.

Abstract: To provide a Si photosensitive member and an image forming apparatus which prevents toner adherence at the time of cleaning and forms an excellent image, an electrophotographic photosensitive member comprising a photoconductive layer including amorphous Si and a surface protective layer which are formed on an electroconductive substrate has a difference in the height of concave and convex corresponding to 90% and 50% of a cumulative frequency of the height of concave and convex with respect to the most deepest point of surface roughness concave and convex within a range of 10 &mgr;m×10 &mgr;m of the photosensitive member as a standard which is set within a range of 3 nm to 200 nm.

Abstract: A function separated laminated electrophotography photosensitive body is equipped with at least a charge generating layer and a charge transport layer on top of a conductive substrate. A contact angle &thgr; of pure water on the charge transport layer satisfies the equation &thgr;>=94°. The resulting organic electrophotography photosensitive body prevents contamination of the photosensitive body surface resulting from component migration from the developing roller and achieves a stable image quality.

Abstract: A toner can be produced by dispersing a colorant in a dispersion medium essentially composed of a polymerizable monomer by using a media-type dispersing device at a tip speed of a stirring body of 3 to 20 m/s with a residence time being 0.03 to 0.5 hour to obtain a monomer composition A; dispersing or dissolving a charge control agent in a dispersion medium to obtain a monomer composition B; dispersing or dissolving a parting agent in a dispersion medium to obtain a monomer composition C; mixing or dispersing the monomer composition A, the monomer composition B and the monomer composition C in a dispersion medium to obtain a polymerizable composition D; and homogenizing the composition D in an aqueous dispersion medium containing a dispersion stabilizer to generate droplets; polymerizing the droplets to obtain colored polymer particles; and attaching an outer-additive on the colored polymer particles.

Abstract: A toner, particularly a color toner suitable for full-color image formation through a substantially oil-less heat-pressure fixing device, is formed from at least a binder resin, a colorant and a wax. The binder resin comprises a polyester-based resin selected from the group consisting of (a) a polyester resin, (b) a hybrid resin having a polyester unit and a vinyl polymer unit, and (c) a mixture of these resins. The wax is characterized by including a structural unit including an OH group, an amide, or an ester group at a specific position.

Abstract: The present invention relates to a mono-component developing device, which develops an electrostatic latent image formed on an electrostatic latent image-supporting member with a toner having a weight-average particle size of from 4 to 10 &mgr;m, a compression rate of not more than 32% and an angle of repose of not more than 38°, and a toner used for the mono-component developing device. Even in the case when a comparatively great stress is imposed on the toner particles, the toner of the present invention maintains superior fluidity and makes it possible to provide a high-quality image.

Abstract: An electrophotographic developer is provided that attains improvement in reliability by improvement in cleaning property and reduction in wear of a photoreceptor in a well-balanced manner without impairing high transfer efficiency and high image quality of a spherical toner. The electrophotographic developer contains a toner and a carrier, the toner containing spherical colored particles having an average shape factor (ML2/A) of about from 100 to 135 and irregular-shaped non-colored particles having a volume average particle diameter of about from 1 to 10 &mgr;m, a charge distribution of the developer having a peak value Q/Ma ascribable to the spherical colored particles and a peak value Q/Mb ascribable to the irregular-shaped non-colored particles, and the peak value Q/Ma and the peak value Q/Mb satisfying both the following formulae (1) and (2): 20 &mgr;C/g≦|Q/Ma|≦85 &mgr;C/g  (1) −0.7 Q/Ma≦Q/Mb≦0.5 Q/Ma  (2).

Abstract: An electrographic process for making a base construction useful for making retroreflective graphic articles is provided.

Abstract: A toner for electrophotography comprising Resin (A) and Resin (B), wherein Resin (A) comprises Resin (C) and a wax dispersed therein, wherein a difference between the softening point of Resin (C) and the melting point of the wax is within 20° C., and the softening point of Resin (B) is higher than the softening point of Resin (C), which can be used for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing, toner jetting and the like.

Abstract: A toner for developing an electrostatic latent image comprising a resin, a colorant and a releasing agent is disclosed. The releasing agent comprises a mixture of a plurality of compounds represented by formula (1) having difference carbon number of carbon atoms in R2 R1—(OCO—R2)n  (1) wherein n represents an integer of 1 to 8 carbon atoms which may has a substituent, R1 is a hydrocarbon group having from 1 to 40, R2 is a hydrocarbon group having from 8 to 40 carbon atoms which may has a substituent.

Abstract: Disclosed are a phthalocyanine composition suitable for use in an electrophotographic photoreceptor that exhibits a high charge potential and a high sensitivity and which exhibits stable performances without causing a change in various properties in repeated use, a process for the production thereof, and an electrophotographic photoreceptor to which the above phthalocyanine composition is applied. The present invention provides a phthalocyanine composition comprising a oxytitanium phthalocyanine and a metal-free phthalocyanine and having a crystal form having peaks at Bragg angles (2&thgr;±0.2°) of 7.0°, 9.0°, 14.1°, 18.0°, 23.7° and 27.3°, and having no peak at a Bragg angle (2&thgr;±0.2°) of 9.5°, in CuK&agr; 1.

Abstract: A process for the preparation of a latex polymer consistent with E/A (emulsion/aggregation/coalescence) toner manufacture. The process utilizes a standard (universal) latex composition and involves chain-transfer agent partitioning, emulsion polymerization that provides a latex polymer with a wide range of molecular properties. In particular, the process customizes a wide range Mw (weight average molecular weight) latex, without substantially varying the Mn (number average molecular weight) and hence, without substantially varying Tg (glass transition temperature) such that good toner performance is maintained. In a preferred process, a latex polymer is prepared by mixing a seed particle latex, generated by aqueous emulsion polymerization of a first portion of a monomer emulsion, with a second portion of the monomer emulsion and at least one chain-transfer agent.

Abstract: A toner including a binder resin; a colorant; and an external additive, wherein the external additive includes a particulate inorganic material, and a silicone oil, wherein the silicone oil is present on the particulate inorganic material in an amount of Ws by weight and present as a free silicone oil in an amount of Wfs by weight, and a free silicone degree defined as a ratio Wfs/Ws is from 10 to 70%.

Abstract: A two-step process for the production of a toner for developing electrostatic images, including a first pulverizing step wherein a toner composition containing a binder and a coloring agent is pulverized to obtain preliminarily pulverized particles having a weight average particle diameter of 20-100 &mgr;m and containing no more than 50% by weight of particles having roundness of 0.90 or less, and a second pulverizing step wherein the preliminarily pulverized particles are finely pulverized to obtain finely pulverized particles having a weight average particle diameter of 5-13 &mgr;m and containing no more than 30% by weight of particles having roundness of 0.90 or less and no more than 15%, based on the total number of particles of the finely pulverized particles, of particles having a particle diameter of 5 &mgr;m or less.

Abstract: Member for a printer, a fax machine, a copier or a toner cartridge, in which said member has a face in contact with toner particles, said face being provided with a top layer in contact with toner particles, said top layer comprising substantially spherical particles with a Mohs hardness of more than 3 or equal to 3 and an average particle size lower than 100 &mgr;m.

Abstract: An electrophotographic developer and a process for forming an image are provided in that the fixing can be conducted at a lower temperature than the conventional technique, and that are excellent in the powder storage stability, the anti-blocking property and the image storage stability after fixing without impairing the density, the coloring property and the transparency of the image after fixing, and further have appropriate electric charging property without any problem of fogging or cloud with excellent maintenance property of electric charge. The electrophotographic developer contains a toner for developing an electrostatic image containing a coloring agent and a binder resin containing, as a main component, a crystalline resin having a melting point of about from 60 to 120° C., and a carrier having a resin film containing a nitrogen-containing resin on a surface thereof. The process for forming an image is carried out by using the electrophotographic developer.

Abstract: In a toner containing at least a binder resin, a pigment and a pigment dispersant, the pigment dispersant has a structure wherein a quinacridone molecular skeleton which is readily adsorptive on the colorant pigment and an oligomer or polymer which has good affinity for the solvent and for the resin serving as a toner binder are covalently bonded. Also disclosed is a process for producing the toner.