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 ?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: 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 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 provides an electrophotographic toner comprising at least a binder resin and a near-infrared light absorbing material containing inorganic material particles, wherein the rate of absorption in the visible region of the electrophotographic toner is 15% or less and the average dispersion diameter of the near-infrared light absorbing material is in a range from 50 nm to 800 nm. The invention also provides an electrophotographic developer comprising the above photographic toner and a carrier. Further, the invention provides an image forming method using the above electrophotographic toner.

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 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 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: 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 black toner comprises a binder resin and black composite particles having an average particle diameter of 0.005 to 0.30 ?m, and comprising: extender pigments as core particles; a gluing agent-coating layer formed on surface of the respective core particles; and a black pigment coat uniformly formed on the gluing agent-coating layer in an amount of 1 to 500 parts by weight based on 100 parts by weight of the extender pigments. Such a black toner using black composite particles having not only excellent blackness, fluidity and light resistance, but also an excellent dispersibility in binder resins, which toner also exhibits excellent blackness, fluidity and light resistance.

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: The present invention provides toners of different colors in which coloring agents of at least four unicolors are internally added to, respectively, and hydrophobic silica particles and metallic soap particles are externally added to toner mother particles, wherein color superposition of the toners is conducted during development of latent images on a latent image carrier or during transfer to a recording medium after the development, being characterized in that the difference (absolute value) between the work functions of two of said toners is 0.02 eV or more, the color superposition is conducted with the toners sequentially from the toner having the largest work function in descending order of work function of the toners, and the difference (absolute value) between the work function of the toner mother particles and the work function of the metallic soap particles is 0.

Abstract: The present invention relates to a magnetic toner composition, and more particularly to a magnetic toner composition having an improved chargeability and excellent uniform chargeability, and that is capable of reducing a difference in electrostatic charge between a toner remaining in a cartridge or in a developing unit and that of a newly supplied toner. A magnetic toner composition of the present invention comprises magnetic toner particulate comprising a binder resin and a magnetic substance, a conductive fine powder having a specific surface area of 30 to 300 m2/g, a hydrophobic silica having a specific surface area of 100 to 240 m2/g, and an inorganic fine powder having an average diameter of 0.1 to 4.O&mgr;m.

Abstract: A nonmagentic one-component toner for an electrophotographic image forming apparatus includes a toner with toner particles, a binder resin having a coloring agent, a charging control agent, and a release agent, and an external additive added to the toner particles. The external additive includes approximately 0.1 to 3.0 wt % of silica having a charge opposite to the toner particles, approximately 0.1 to 3.0 wt % of silica having a same charge as the toner particles, and approximately 0.1 to 4.0 wt % of titanium dioxide.

Abstract: An electrophotographic developer comprising at least one element selected from the group consisting of boron and phosphorus in a content of 0.1 to 100 ppm, which the developer is excellent in flowability and shelf stability, does not give image defects such as occurrence of white stripes and attains almost constant image quality even when the ambient conditions including temperature and humidity fluctuate. A production process of a polymerized toner used in the developer, a production process of the developer, and an image forming process.

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: The present invention provides a toner containing toner mother particles containing a binder resin and a colorant having added thereinto external additives, e.g., positively electrifiable silica fine particles, negatively electrifiable silica fine particles, titanium oxide fine particles and a long chain fatty acid or a salt thereof, wherein the external additives are added by multistage process, thereby is low in desorption of external additives, has the electrification property for a long period of time, shows high flowability and transfer efficiency, and is not accompanied by the reduction of image density.

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: A toner for electrostatic latent image development having coloring particles containing at least a binding resin, a coloring agent and a release agent, and an external additive, wherein a variation in a number average particle diameter of the coloring particles is 25 or less, an average circularity of the coloring particles is 0.975 or more, and a variation in a circularity of the coloring particles is 2.5 or less.

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: By simultaneously atomizing a siloxane and two organometallic compounds of different metals M1 and M2 exclusive of silicon in a flame for combustion, spherical amorphous ternary complex oxide fine particles are obtained which are substantially free of chlorine, have a particle size of 10-500 nm, and have a silica content A of 1-99 wt %, a M1 oxide content B of 1-90 wt % and a M2 oxide content C of 1-90 wt %, all based on the weight of oxides excluding carbon, provided that A+B+C≈100. An electrostatic image developer comprising the fine particles is improved in fluidity and cleanability and bears a uniform and stable quantity of electric charge.

Abstract: The present invention provides a toner: comprising a binder resin comprising a polyester unit, a colorant, a releasing agent, and inorganic fine particles; has a weight average particle diameter of 3.0-6.5 &mgr;m; has an average circularity of particles in the toner each having a circle-equivalent diameter of 2 &mgr;m or more of 0.920-0.945; has a BET specific surface area of 2.1-3.5 m2/g; and has a permeability of light of a wavelength of 600 nm in a liquid having dispersed the toner in a 45 vol % methanol aq. of 30-80%. The present invention also provides a two-component developer: comprising the toner and a magnetic carrier comprising magnetic core particles coated by a coating layer; and has a number average particle diameter of 15-80 &mgr;m. Using the toner and the two-component developer enables a high-quality image to be formed at a high speed even in an oilless fixing system.

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 having toner particles containing a binder resin and a colorant; and a first external additive having 0.1 to 3.0 wt % of large silica particles with an average particle size of 20 to 200 nm; a second external additive having 0.1 to 3.0 wt % of small silica particles with an average particle size of 5 to 20 nm; a third external additive having 0.1 to 2.0 wt % of hydrophobic titanium dioxide microparticles with a resistance of 105 to 1012 &OHgr;cm; and a fourth external additive having at least one of 0.1 to 2.0 wt % of conductive titanium dioxide particles with a resistance of 1 to 105 &OHgr;cm and 0.1 to 2.0 wt % of positively chargeable aluminum oxide particles. Therefore, a thin toner layer with a uniform toner amount is formed on a toner carrier and stable charge distribution and toner flowability are maintained for a long time, thereby resulting in prevention of fog and toner scattering, and improvements in developing efficiency and toner durability.

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: A toner including toner particles including a binder resin and a release agent, wherein when the toner is molded into a plate upon application of a pressure of 478 kg/cm2, the toner plate has a surface having a coefficient of static friction of from 0.20 to 0.40. An image forming apparatus including an image bearing member, an image developer to form a toner image on the image bearing member, an image transferer configured to transfer the toner image on a receiving material and a fixer configured to fix the toner image thereon, wherein the apparatus has a waiting time not longer than 15 seconds, and a maximum power consumption not greater than 1.5 KW and 30 W in an image forming state and in a standby state, respectively, wherein the toner is the toner mentioned above.

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.

Abstract: An image-forming process, which comprises steps of developing an electrostatic latent image on an inorganic photoreceptor with an electrostatic image developer containing 0.1 to 5.0% by weight, based on the toner particles, of silicon carbide fine powder of 0.2 to 1.5 &mgr;m in average primary particle size, 10 to 50 m2/g in specific surface area and 10 to 60% in amount of agglomerated particles, said silicon carbide fine powder being contained in an amount of 0.1 to 5.0% by weight, transferring the developed image to a transfer member, then removing residual toner particles on the photoreceptor by means of a cleaning blade.

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: 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 toner for MICR comprises at least a binder resin, magnetite particles comprising a mixture of granular magnetite and acicular magnetite, and a wax, wherein a ratio by weight of said acicular magnetite in said magnetite particles is 0.1-0.5 to the granular magnetite of 1.0, said magnetite particles are contained in an amount of 15-50% by weight in the toner, said granular magnetite has residual magnetization of 5-15 emu/g and saturation magnetization of 70-95 emu/g, and said acicular magnetite has residual magnetization of 20-50 emu/g and saturation magnetization of 70-95 emu/g.

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 having high mechanical strength and being capable of exhibiting a sufficient fixing property in a wide temperature range is provided. Further, a fixing device and an image forming apparatus in which such a toner can be suitably used are provided. The toner contains polyester-based resin as a main resin component, and the acid value of the toner is 8.0 KOHmg/g or less. The polyester-based resin includes block polyester mainly composed of a block copolymer, and amorphous polyester having crystallinity lower than that of the block polyester. The block polyester has a crystalline block obtained by the condensation of a diol component with a dicarboxylic acid component and an amorphous block having crystallinity lower than that of the crystalline block.

Abstract: In a toner kit having i) a non-magnetic black toner having at least carbon black and ii) color toners, the black toner has a weight-average particle diameter represented by D4b and a one-point method BET specific surface area represented by Sb, and the color toners, other than the black toner, each have a weight-average particle diameter represented by D4c and a one-point method BET specific surface area represented by Sc, where the black toner and color toners satisfy the following relations (1) and (2):

Abstract: The present invention provides a silica fine particle capable of preventing a charging member or an image bearing member from being contaminated with toner when the toner contains the particle and also capable of providing the toner with a stable developing property. The silica fine particle of the present invention has been hydrophobic treated. Furthermore, the particle has a peak in a range of 0.04 &mgr;m to 1 &mgr;m and a peak in the range of 1 &mgr;m to 100 &mgr;m in a volume-basis particle diameter distribution. The particle has a frequency ratio of 10 to 80% for the particles with a particle diameter of 0.04 &mgr;m to 1 &mgr;m to a total of all the peaks, and the particles has the frequency ratio of less than 16% for the particles with a particle diameters of 20 &mgr;m to 2000 &mgr;m to the total of all the peaks.

Abstract: A toner including toner particles including a binder resin and a colorant, wherein particles of the toner have such a rolling property as to relatively easily roll in one direction compared to other directions. It is preferable that the toner particles preferably have a spindle form and satisfies the following relationships: 0.5≦(r2/r1)≦0.8, 0.7≦(r3/r2)≦1.0, and r3≦r2≦r1, wherein r1, r2 and r3 represent an average major axis particle diameter, an average minor axis particle diameter and an average thickness of the toner particles. An image forming apparatus including at least an image bearing member; a developing device configured to develop an electrostatic latent image with a developer including the above-mentioned toner; a transferring device configured to transfer a toner image onto a receiving material; and a cleaning device configured to clean a surface of the image bearing member.

Abstract: A toner composition, comprising a binder resin, a wax, a copolymer and a colorant;

Abstract: The present invention provides a toner which ensures large mean charging amount and excellent transfer efficiency with no or little amount of reversely charged toner and provides an image forming apparatus using the same. The toner is produced by adding external additives to resin particles containing a coloring agent, wherein the external additives are silica particles and modified silica particles of which outer surfaces are modified with oxide or hydroxide of at least one metal selected from a group consisting of titanium, tin, zirconium, and aluminum, the amount of the modified silica particles being 1.5 times or less of the amount the silica particles. The image forming apparatus uses the toner.

Abstract: An electrostatic developing toner which can effectively suppress image fogging*1 by setting a ratio (d/D) of the average particle diameter D of the toner and the average particle diameter d of iron oxide particles contained in the toner as a colorant to within a predetermined range, and by setting the value of a ratio (&sgr;r/&sgr;s) between the residual magnetization rr and saturation magnetization &sgr;s of the iron oxide particles to a predetermined value or less, is provided. The value of the ratio (d/D) of the average particle diameter D of the toner and the average particle diameter d of iron oxide particles contained in the toner as a colorant is set to within the range of 0.01-0.03, and the value of the ratio (&sgr;r/&sgr;s) between the residual magnetization &sgr;r and saturation magnetization &sgr;s of the iron oxide particles is set to 0.3 or less.

Abstract: A toner of the present invention comprises at least a binder resin comprising as a main component a polyester resin, a wax, and a colorant, in which in case of measuring a wettability of the toner with respect to a mixed solvent of methanol and water in terms of an optical transimittance at an optical wavelength of 780 nm, a methanol concentration of the mixed solvent is in a range of 45 to 65% by volume when an optical transmittance is 80% and 10%, respectively; a melt index (MI) is of 0.1 to 10 g/10 min at a temperature of 125° C.

Abstract: A developer, which includes a base toner containing at least a binding resin and a coloring agent; and inorganic fine particles; wherein the base toner satisfies 105≦SF-1≦130 and 120≦SF-2≦180, wherein SF-1=((absolute maximum length of a particle of the base toner)2/area of the particle of the base toner)×(&pgr;/4)×100, wherein SF-2=(peripheral length of the particle of the base toner)2/(area of the base toner)×(¼&pgr;)×100, wherein the inorganic fine particles have an average particle diameter that ranges between 30 nm to 160 nm.

Abstract: An external additive for a toner for electrophotography which contains oxide fine particles which contain silicon, in which the oxide fine particles have a primary particle diameter of 30 nm to 300 nm in number average, a standard deviation &sgr; of a particle size distribution of the primary particle diameter satisfies a relation of: R/4≦&sgr;≦R in which the R expresses the primary particle diameter,

Abstract: A toner comprising a resin binder, a colorant, and fine inorganic particles having a BET specific surface area of 30 m2/g or less, wherein the fine inorganic particles are added as an external additive, wherein the toner has a storage modulus at 100° C. using a 25 mm parallel plate of 7×104 Pa or less, a storage modulus at 60° C. using a 7.9 mm parallel plate of from 3×108 to 1×109 Pa, and a storage modulus at 70° C. using a 7.9 mm parallel plate of from 7×106 to 3×108 Pa; and a two-component developer comprising the toner. 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: A toner composition including toner particles; and an external additive located on the surface of the toner particles and including Si, wherein the toner composition satisfies the following relationship, (PSi2p (1 min)−PSi2p (30 min))≦0.8 eV, wherein PSi2p (1 min) and PSi2p (30 min) represent positions of the Si2p peaks of the Si element of the toner composition when the toner composition is subjected to an X-ray photoelectron spectroscopy analysis after the toner composition is mixed with a carrier for 1 minute or 30 minutes using a TURBULA mixer at a revolution of 20 rpm, respectively.

Abstract: A toner for developing a latent electrostatic image including a base of toner particle which contains a binder resin and a coloring agent, and an external additive. Herein, a plurality of the base of toner particle has a volume average particle diameter (Dv) of 3 &mgr;m to 7 &mgr;m, a ratio (Dv/Dn) of the volume average particle diameter (Dv) to a number average particle diameter (Dn) is 1.01 to 1.25, a plurality of the base of toner particle contains 15% by number or less of the base of toner particle having a particle diameter of 0.6 &mgr;m to 2.0 &mgr;m, a plurality of the base of toner particle has a circularity of 0.930 to 0.990 on average, the binder resin contains a modified polyester resin, and the toner contains 0.3 parts by weight to 5.0 parts by weight of the external additive, relative to 100 parts by weight of the base of toner particle.

Abstract: A non-magnetic single-component toner comprises: silica A having a specific surface area of 30 to 70 m2/g as determined by a BET method, and having a surface which is at least treated with aminosilane, silica B having a specific surface area of 100 m2/g or more, and having a surface which is treated with silicone oil, silicone oil, and toner particles containing a binder resin and a colorant wherein silica A, silica B, silicon oil are adhered to surfaces of the toner particles, so that the toner that has suitable charging properties and anti-fusing and long life under all environmental atmosphere, and allows the obtaining of stable images having minimal back ground fogging, proper image density, no image density unevenness, and no voids in image (particularly on thick paper), and superior solid black reproducibility.

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: According to the present invention, there is provided an image forming apparatus including developing units which develop latent images formed on image carriers for colors of yellow, magenta, cyan, and black using toners of the corresponding colors, transfer units which transfer toner images in the respective colors formed on the image carriers onto the same transfer body, and a fixing unit which fixes the toner images, and toner preferably used in the image forming apparatus. The developing unit performs development using toner in which, out of five materials of silica, titania, barium sulfate, fine polymer particles, and a lubricant, materials not including either fine polymer particles or barium sulfate are fixed as an external additive, in order to avoid poor transfer and toner filming, improve the cleaning properties, and form an excellent image.

Abstract: An electrophotographic toner containing: a fixing resin, a colorant, and wax. The wax at least contains hydrocarbon wax having a number-average molecular weight of not higher than 600, and polyethylene wax having a number-average molecular weight of not higher than 600, a melting viscosity of lower than 15 mPa·s at 140° C. and a crystallinity of lower than 95%. A ratio of the hydrocarbon wax to the polyethylene wax is in a range of from 1:10 to 2:1. A maximum of absorption peaks in a heat-up time absorption calorie curve in a DSC curve of the toner measured by a differential scanning calorimeter is at a temperature not higher than 75° C. An onset temperature in absorption of heat is not higher than 65° C.

Abstract: To provide a toner which exhibits excellent performances for image characteristics, and also has excellent performances for charging property even if the toner is used in a cleaning simultaneous with developing system having a direct injection charging mechanism. The toner of the present invention comprises toner particles and non-magnetic metallic-compound fine particles. The weight average particle diameter of the toner is 3.0 &mgr;m to 12.0 &mgr;m. The metallic-compound fine particles are conductive metallic-compound fine particles having a specific surface area (cm2/cm3) of 5×105 to 100×105; a medium diameter (D50) of 0.4 &mgr;m to 4.0 &mgr;m with respect to a volume-basis particle diameter distribution, the medium diameter (D50) being smaller than a weight average particle diameter of the toner; and a 90% particle diameter D90 of 6.0 &mgr;m or less with respect to a volume-basis particle diameter.

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.