Abstract: A developer comprising toner particles containing at least a binder resin and a colorant, an inorganic fine powder whose primary particles have a number-average particle diameter of from 4 nm to 50 nm, and a conductive fine powder whose primary particles have a number-average particle diameter of from 50 nm to 500 nm. The conductive fine powder contains an agglomerated matter of the primary particles. The developer comprises 15% to 60% by number of particles having particle diameters in the range of from 1.00 &mgr;m, inclusive, to 2.00 &mgr;m, exclusive, and 15% to 70% by number of particles having particle diameters in the range of from 3.00 &mgr;m, inclusive, to 8.96 &mgr;m, exclusive, in number-based particle size distribution of particles having particle diameters in the range of from 0.60 &mgr;m, inclusive, to 159.21 &mgr;m, exclusive. Also, an image forming method and a process cartridge are disclosed which make use of the developer.

Abstract: A developer for developing an electrostatic latent image is formed from toner particles each comprising a binder resin and a colorant, inorganic fine powder having a number-average particle size of 4-80 nm based on primary particles, and electroconductive fine powder. The developer is characterized by having a number-basis particle size distribution in the range of 0.60-159.21 &mgr;m including 15-60% by number of particles in the range of 1.00-2.00 &mgr;m, and 15-70% by number of particles in the range of 3.00-8.96 &mgr;m, each particle size range including its lower limit and excluding its upper limit. As a result of inclusion an appropriate amount of the electroconductive fine powder represented by the particle size fraction of 1.00-2.

Abstract: Magnetic toner particles are disclosed. The magnetic toner particles contain at least one polymeric binder and at least one magnetic additive, wherein the surface of the toner particle contains particles of positively chargeable inorganic fine powder particles. The inorganic fine powder particles have a mean volume average particle size of from about 0.5 to about 7 &mgr;m, and a cleaning ratio of from about 0.1 to about 5.0 and a cleaning ratio being the volume fraction of particles between 0 and 1.0 &mgr;m, divided by the volume fraction of particles greater than 1.0 &mgr;m; and the toner particles having on the surface thereof a flowability improving agent having a BET surface area of at least about 30 m2/g. Methods of forming electrostatic images are further disclosed. Also, images formed from the magnetic toner particles are further disclosed and have excellent character void frequency, total void area, and suitable magnetic signal strengths.

Abstract: In a toner T of the present invention, the liberated mother particle ratio is set to be 10% or less and the liberated silica particle ratio is set to be 0.2-10%, thereby reducing the possibility that the liberated mother particles 18′ and the mother particles 18 with silica particles 19 therein will be fused on toner-contact members such as a latent image carrier, a toner carrier, and a toner regulating member, and thus effectively preventing the filming of toner T. Therefore, according to the toner T of the present invention, the durability of the toner-contact members such as the latent image carrier, the toner carrier, and the toner regulating member can be improved.

Abstract: By reducing non-transferred toner on a photosensitive member, image density is sufficiently maintained and fogging in the non-imaged portion is prevented. The developing agent for non-magnetic monocomponent development is a toner comprising toner particles and an external additive adhered on the surface of the toner particles, wherein the external additive comprises inorganic fine particles (A), which are surface-treated with aminosilane and dimethylpolysiloxane and have a polarity reverse to that of the toner, and inorganic fine particles (B) having the same polarity as that of the toner.

Abstract: A positively chargeable toner for two-component development comprising a resin binder; a colorant; a releasing agent comprising a wax having a melting point of 50° to 120° C.; and an external additive comprising a positively chargeable silica, the positively chargeable silica having an absolute deviation of an error of 0.1 or less, against an approximate straight line showing an adhesion state of silicon atoms to carbon atoms, and a free ratio of 5% or less, wherein the positively chargeable toner is usable together with a ferrite carrier having a saturation magnetization of from 40 to 100 Am2/kg. This positively chargeable toner is used for development of an electrostatic latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.

Abstract: Regarding the metal oxide fine powder, which is used as the additive of a powder material and is hydrophobic treated on the surface, the peak of the particle size distribution of the agglomerated particle is made to be less than the same level of average size of the powder material, so that said powder has high dispersibility in the powder material. When this metal oxide fine powder is used as the external additive, such as the toner for the electronic photograph, the standup of the electrostatic charge, the image quality, and the cleaning characteristic are improved remarkably.

Abstract: A magnetic toner for MICR printers is provided with a binder resin, magnetic powder, and metal oxide particles which are in the outer surface of each toner base particle made from the binder resin and the magnetic powder, the metal oxide particles having a volume resistivity of 1×105 to 1×1011 &OHgr;·cm. A developer containing this MICR toner makes it possible to provide superior image density and reading precision, even after 150,000 to 300,000 sheets of A-4 paper have been continuously printed.

Abstract: In a negatively chargeable toner having i) negatively chargeable toner particles containing at least a binder resin, a colorant and a vinyl copolymer and ii) an inorganic fine powder, the negatively chargeable toner has a weight-average particle diameter of from 4 &mgr;m to 12 &mgr;m and contains, in particle size distribution of the toner, less than 50% by volume of particles of 10.1 &mgr;m or more in particle diameter, and the vinyl copolymer is a vinyl copolymer obtained by copolymerizing a monomer composition which contains at least i) a vinyl monomer such as an N-substituted acryl- or methacrylamide or a ring-structure acryl- or methacrylamide and ii) a vinyl monomer having as a functional group a carboxyl group or a carboxyl group made into salt structure. An image-forming method and a process cartridge make use of such a negatively chargeable toner.

Abstract: The invention relates to a static latent image developing toner comprising toner particles, each of the toner particles comprising a toner intermediate particle having inorganic oxide particles on the surface, wherein a surface existence density of the inorganic oxide particle having a feret's diameter of 110 nm to 160 nm on the toner intermediate particle is 5 to 50 per &mgr;m2, and relates to a developer comprising the toner and an image forming method utilizing the toner.

Abstract: An electrostatographic toner composition consists essentially of noncrosslinked linear polymeric toner particles, about 0.7 wt. % to about 4 wt. % of hydrophobic silica particles disposed on the surface of the toner particles, and about 0.1 wt. % to about 2 wt. % of particles of a fatty acid metal salt disposed on the surface of the toner particles, wherein the weight percentages of the hydrophobic silica particles and the particles of a fatty acid metal salt are based on the weight of the polymeric toner particles. An electrostatographic developer is formed by mixing the toner composition so prepared with hard magnetic carrier particles. A process for forming an electrostatographic toner composition comprises: providing noncrosslinked polymeric toner particles of a selected particle size, and dry blending the polymeric toner particles with a mixture consisting essentially of about 0.7 wt. % to about 4 wt. % of hydrophobic silica particles and about 0.1 wt. % to about 2 wt.

Abstract: In a toner T of the present invention, the liberated mother particle ratio is set to be 10% or less and the liberated silica particle ratio is set to be 0.2-10%, thereby reducing the possibility that the liberated mother particles 18′ and the mother particles 18 with silica particles 19 therein will be fused on toner-contact members such as a latent image carrier, a toner carrier, and a toner regulating member, and thus effectively preventing the filming of toner T. Therefore, according to the toner T of the present invention, the durability of the toner-contact members such as the latent image carrier, the toner carrier, and the toner regulating member can be improved.

Abstract: An image is formed by using in combination a photoreceptor having a surface roughness Rz not larger than 1.0 and a developing agent comprising a toner containing toner particles containing a binder resin and a coloring agent, silica particles, and a metal soap, the weight ratio of the silica particles to the metal soap falling within a range of between 10 and 60.

Abstract: A full color image forming method including the steps of developing an electrostatic latent image formed on an image bearing member with a color toner to form a color toner image thereon; first transferring the color developer including a color toner image onto an endless intermediate transfer material while applying a developing bias thereto; repeating the above-mentioned steps a plurality of times using a plurality of different color developers to form a full color toner image on the intermediate transfer material; and second transferring the full color image onto a receiving material, wherein a weight of each of the color toner images formed on the image bearing member is from about 0.4 mg/cm2 to about 1.5 mg/cm2, and each of the color developers has a charge quantity not less than 15 &mgr;C/g in an absolute value, and wherein the following relationship is satisfied with respect to each of the first color toner transferring steps: 5.4×Q1+90<Vb−V1<5.

Abstract: An electrophotographic toner is formed as a blend of toner particles and external additives. The external additives include (1) first inorganic fine particles having an average primary particle size of 80-800 nm of oxide of a metal selected from the group consisting of titanium, aluminum, zinc and zirconium, (2) second inorganic fine particles other than silica having an average primary particle size of below 80 nm and (3) silica fine particles having an average primary particle size of below 30 nm. As a result, the toner can be made free from difficulties, such as melt-sticking onto an image-bearing member in a low humidity environment, roughening of halftone images in a low humidity environment, toner blot-down after storage at high temperatures or in continuous image formation on a large number of sheets, fog in continuous formations of images of low color area percentage in a low humidity environment, and re-transfer in multi-color image formation.

Abstract: An external additives for electrophtographic toner comprising finely divided oxide particulate including a silicon compound and a compound for doping said oxide particulate, wherein particle diameter of the primary particle of said finely divided oxide particulate is in the range of 30 nm to 150 nm, and the primary particle of said finely divided oxide particles is substantially spherical shape having the roundness in the range of 0.95 to 0.996, is provided. And this external additives is capable of evading from the embedding of external additives into toner even if after the toner is held in the storage under the condition of high temperature and high humidity, thereby the additives is capable of showing sufficient functions as fluidizing agent and charge supplement agent, and is capable of inhibiting an abnormal charge elevation even after being stored under the low temperature and low humidity.

Abstract: Development systems and methods for developing using magnetic toner are disclosed. The present invention further discloses developers used in development systems as well as the toner used in developer for magnetic ink character recognition printing. With respect to the development system, a development system is disclosed which includes a supply of dry developer mixture which contains magnetic toner particles and hard magnetic carrier particles. The development system further includes a non-magnetic, cylindrical shell for transporting the developer between the supply and the development zone, wherein the shell can be rotatable or stationary. A rotating magnetic core of a pre-selected magnetic field strength and means for rotating at least the magnetic core to provide for the transport of the toner particles from the shell to an electrostatic image also provided as part of the development system.

Abstract: In order to control the filming, a developer comprises developer primary particles, each comprising at least a resin and a colorant and an additive agent added to the developer primary particles and having a particle diameter smaller than that of the developer primary particles, wherein an extrication amount of the additive agent in the developer primary particles is smaller than 5.2×10−5 part by weight with respect to the developer primary particles.

Abstract: A developer includes developer main particles and abrasive particles added to the developer main particles. The developer main particles include at least a resin material and a coloring material. The abrasive particles and the developer main particles are opposite in polarity when they are charged. The abrasive particles have an average diameter in the range of 50 to 5000 nm and preferably in the range of 150 to 2000 nm. A fluidity-adding agent is added to the developer main particles. The fluidity-adding agent has a diameter in the range of 5 to 40 nm. The fluidity-adding agent is at least 0.1 weight parts with respect to the developer main particles, and the abrasive particles are in the range of 0.02 to 1.2 weight parts.

Abstract: The present invention relates to toners for full color image-forming machine with specific external additives (kind, BET specific surface area etc.) added externally in combination to toner particles prepared by a wet granulation method, and a fixing method suitable for the toner.

Abstract: A toner comprising a resin binder, a colorant, and externally-added inorganic fine particles, comprising large-particle size inorganic particles comprising 50% by volume or more of particles having a particle size of from 100 to 583.9 nm, and having a BET specific surface area of 1 to 40 m2/g. The toner can be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: In an electrophotographic developer and a process for forming an image, an electrophotographic toner used therein contains spherical toner parent particles and two or more kinds of inorganic particles having different average particle diameters, at least one kind of the inorganic fine particles being spherical particles having an average primary particle diameter of about 80 to 300 nm, and the inorganic particles containing the spherical particles being attached to the toner parent particles to provide a structure satisfying the following conditions (1) and (2): (1) the spherical particles have a coverage on a surface of the toner parent particles of about 20% or more; and (2) a proportion of the inorganic particles that are separated from the toner parent particles upon dispersing the toner in an aqueous solution is about 35% or less of a total addition amount of the inorganic particles.

Abstract: A toner includes a resin, colorant, and a silicate component bound to the toner. The silicate component can be a water-soluble cationic complex of at least one of tetraalkylammonium and tetraalkylphosphonium. A method for making the toner includes the surface treatment of the toner with a water-soluble silicate.

Abstract: A toner for developing an electrostatic image, comprising toner particles each containing at least a colorant and a resin, and an external additive present on each of the toner particles, wherein the water wettability of said toner particles without the external additive is W0, wherein the water wettability of the toner is W100, and wherein (W100−W0)/W100 is not greater than 0.3.

Abstract: A toner composition includes a binder, a colorant, and surface-treated sol-gel metal oxide particles surface-treated with a treatment agent.

Abstract: Development systems and methods for developing using magnetic toner are disclosed. The present invention further discloses developers used in development systems as well as the toner used in developer for magnetic ink character recognition printing. With respect to the development system, a development system is disclosed which includes a supply of dry developer mixture which contains magnetic toner particles and hard magnetic carrier particles. The development system further includes a non-magnetic, cylindrical shell for transporting the developer between the supply and the development zone, wherein the shell can be rotatable or stationary. A rotating magnetic core of a pre-selected magnetic field strength and means for rotating at least the magnetic core to provide for the transport of the toner particles from the shell to an electrostatic image also provided as part of the development system.

Abstract: A non-magnetic single-component toner 8 of the present invention has toner mother particles 8a, and external additives 12 comprising: two hydrophobic silicas 13, 14 of which particle diameters are different from each other, i.e. a mean primary particle diameter of 7 nm to 12 nm and a mean primary particle diameter of 40 nm to 50 nm, and a hydrophobic rutile/anatase type titanium oxide 15 having a spindle shape of which major axial diameter is in a range from 0.02 nm to 0.10 nm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, wherein the external additives 12 adhere to the toner mother particles 8a. By the hydrophobic silicas 13, 14 having work function smaller than the work function of the toner mother particles 8a, the negative charging property is imparted to the toner mother particles 8a and the fluidity is also insured.

Abstract: A non-contact type non-magnetic monocomponent toner to develop electrostatic latent images and a developing apparatus using the same. The toner includes toner particles containing a binding resin and coloring agents; and an external additive powder containing silicon oxide powder that has at least two kinds of particle sizes, separate inorganic compound powder, and zinc stearate. After passing a toner layer-regulating member, the toner evenly maintains a toner amount formed on a developing roller and forms a thin toner layer.

Abstract: A full color image forming method including the steps of developing an electrostatic latent image formed on an image bearing member with a color toner to form a color toner image thereon; first transferring the color developer including a color toner image onto an endless intermediate transfer material while applying a developing bias thereto; repeating the above-mentioned steps a plurality of times using a plurality of different color developers to form a full color toner image on the intermediate transfer material; and second transferring the full color image onto a receiving material, wherein a weight of each of the color toner images formed on the image bearing member is from about 0.4 mg/cm2 to about 1.5 mg/cm2, and each of the color developers has a charge quantity not less than 15 &mgr;C/g in an absolute value, and wherein the following relationship is satisfied with respect to each of the first color toner transferring steps: 5.4×Q1+90 <Vb−V1<5.

Abstract: A toner suitable for use in an image forming method including a contact charging step is provided. The toner includes: toner particles comprising at least a binder resin and a colorant, and fine particles. The fine particles comprise: (i) a tungsten-containing tin oxide, or (ii) base particles, and a tungsten-containing tin compound coating the base particles, the fine particles contain tin (Sn) in a weight ratio (Sn/b) of 0.01 to 2.0 with respect to the base particles (B). In the fine particles, tungsten (W) is contained in a mol ratio (W/Sn) of 0.001 to 0.3 with respect to the tin (Sn).

Abstract: The present invention is directed to a non-contact, single-component developing system for electrophotographic machines that effectively reduces the impact of adhesion forces on the development process. The developing system of the present invention utilizes a single-component toner that tends to reduce the adhesion forces that hold the toner particles on a toner support member. Preferably, the toner is combined with large and small silica particles having a concentration by weight that results in an optimum surface coverage of toner particles by large and small silica particles that facilitates a reduction in the adhesion forces holding the toner particles on the toner support member.

Abstract: A silylated silica having an SiOH density per nm2 of less than 0.6, based on the BET-method surface area (DIN 66131 and 66132), is prepared by silylating silica in a process where loading, reacting, and purifying are performed in separate steps.

Abstract: A toner composition includes a binder, a colorant, and surface-treated sol-gel metal oxide particles surface-treated with a treatment agent.

Abstract: The present invention relates to a negatively chargeable toner, comprising:

Abstract: The invention provides a toner which can maintain sufficient image density upon continuous copying in a recycle system even under any environmental conditions without causing troubles such as fogging and toner dusting. The toner for recycle system comprises toner particles which contain, as a binder resin, at least a cycloolefin copolymer resin and, as a releasing agent, at least a polypropylene wax, and fine silica particles adhered to the surface of said toner particles. This toner is used for a toner recycling type developing method, in which the toner remaining on the surface of the photosensitive member is recovered into the developing device and is reused.

Abstract: A two-component developer comprising a toner onto which a hydrophobic silica having an average particle size of 25 nm or more is externally added, and a carrier having a saturation magnetization of from 50 to 95 Am2/kg, wherein the carrier has a ratio of surface resistivity to volume resistivity of from 1×102 to 1×104 m−1 at an electric field strength of 100 V/cm; and a method for development comprising applying the above two-component developer to an electrophotographic device comprising a photoconductor having a peripheral speed of 400 mm/sec or more, and developing a latent image. The two-component developer can be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: A toner comprising a resin binder comprising a crystalline resin; a colorant; and fine inorganic particles, the fine inorganic particles being externally added thereto, wherein a coating ratio of the fine inorganic particles on a surface of the toner is 130 to 300%. The toner can be suitably used for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Abstract: A nonmagnetic black toner comprising a resin binder, a black colorant comprising a metal oxide, and externally-added fine particles having an average particle size of 20 nm to 2.1 &mgr;m, wherein the fine particles are contained in the toner in an amount of 0.2% by weight or more. The nonmagnetic black toner can be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: Provided are a toner and its production, a developer, an image forming method and an image forming apparatus. The toner has excellent fixation characteristics of good releasability, hot offset resistance, folding resistance, surface glossiness, and OHP transparency. The toner contains a binder resin, a colorant, a release agent and an inorganic particles. The inorganic particles therein contain inorganic particles (A) having the mean primary particle size not less than approximately 5 nm and less than approximately 30 nm and inorganic particles (B) having the mean primary particle size not less than approximately 30 nm and less than approximately 200 nm.

Abstract: A toner composition that permits printing of clear-cut and high image quality without developing a fog or a blur is provided.

Abstract: An electrophotographic toner is formed as a blend of toner particles and external additives. The external additives include (1) first inorganic fine particles having an average primary particle size of 80-800 nm of oxide of a metal selected from the group consisting of titanium, aluminum, zinc and zirconium, (2) second inorganic fine particles other than silica having an average primary particle size of below 80 nm and (3) silica fine particles having an average primary particle size of below 30 nm. As a result, the toner can be made free from difficulties, such as melt-sticking onto an image-bearing member in a low humidity environment, roughening of halftone images in a low humidity environment, toner blot-down after storage at high temperatures or in continuous image formation on a large number of sheets, fog in continuous formations of images of low color area percentage in a low humidity environment, and re-transfer in multi-color image formation.

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 toner comprising: a plurality of mother particles; and a plurality of external additive particles to be attached to the mother particles, the external additive particles including external additive particles attached to the mother particle and external additive particles liberated from the mother particles, wherein an inclination (particle sizes of the external additives/particle sizes of the mother particles) of an approximation straight line obtained by approximating distribution of particle sizes of the external additives with respect to the particle sizes of the mother particles by a least-square method is not larger than 0.6. Also, disclosed is an image forming apparatus using the toner.

Abstract: The present invention is directed to a non-contact, single-component developing system for electrophotographic machines that effectively reduces the impact of adhesion forces on the development process. The developing system of the present invention utilizes a single-component toner that tends to reduce the adhesion forces that hold the toner particles on a toner support member. Preferably, the toner is combined with large and small silica particles having a concentration by weight that results in an optimum surface coverage of toner particles by large and small silica particles that facilitates a reduction in the adhesion forces holding the toner particles on the toner support member.

Abstract: Regarding the metal oxide fine powder, which is used as the additive of a powder material and is hydrophobic treated on the surface, the peak of the particle size distribution of the agglomerated particle is made to be less than the same level of average size of the powder material, so that said powder has high dispersibility in the powder material. When this metal oxide fine powder is used as the external additive, such as the toner for the, electronic photograph, the standup of the electrostatic charge, the image quality, and the cleaning characteristic are improved remarkably.

Abstract: A dry, powder electrostatic toner having polyester resin as a binder, pigment as a colorant, charge control ingredients polyethylene wax as a release agent, and extra particulate elements to improve flow and to scrub the doctor blade, one extra particular element is hydrophilic rutile acicular titanium oxide with aluminum oxide surface treatment, two silicas are blended within the bulk of the toner, one of BET surface area of about 30 m2/g and one of BET surface area of about 380 m2/gn; and an organoboron complex negative exchange control agent is blended with a quaternary ammonium salt of an aluminosilicate compound negative charge control agent. Improved functioning as a toner is realized.

Abstract: An electrophotographic color toner containing at least a coloring agent, a binder resin, and light-color or colorless fine particles, wherein toner particles containing particles having particle sizes of at least 1.0 &mgr;m as said fine particles are not more than half of the total toner particles. The electrophotographic color toner has a broad fixable temperature region of the toner and does not cause an image deterioration by preventing the occurrence of the penetration phenomenon into a paper while keeping a high image quality and high coloring even by using paper other than a paper for color copy without deteriorating various characteristics of a toner of prior art.

Abstract: A toner, a developing method and apparatus is provided to satisfy both the low temperature fixation property and the hot offset property and that has a wide range of fixing temperature. The toner for an image formation comprises at least metal materials in a binding resin, wherein the toner is measured by a stand-alone type flow tester, and has a softening temperature of 65˜77.5° C., a flow beginning temperature of 100˜120° C., a melt temperature by a ½ method is 145˜195° C., and an average length of a short axis of a primary particle of the metal materials is 0.01-0.4 &mgr;m.

Abstract: A jump monocomponent development arrangement includes a dielectric photoreceptor belt having an image-bearing surface for receiving an electrostatic charge image and a development station having a supply of toner particles with a mean diameter in a range from 8 microns to 14 microns and including large and small additive particles having mean diameters in size ranges of 6 to 12 nm and 20 to 50 nm, respectively, and in amounts sufficient to provide surface coverage of the toner particles in ranges from about 5 percent to about 50 percent and about 50 percent to about 150 percent, respectively.

Abstract: An external additive for a toner, having an average primary particle diameter not greater than 100 nm and including at least inorganic fine particles and a hydrophobizing agent applied to the surface of the inorganic fine particles, wherein after the external additive is treated with chloroform, pyrolysates of the residual components include a compound having at least one structure selected from organopolysiloxane structures and ring siloxane structures.