Abstract: The present invention is to provide a positively-chargeable toner for developing electrostatic images, which is excellent in reproductivity of thin lines and in durability and has a stable charging ability and flowability over time. A positively-chargeable toner comprises a colored resin particle and external additives, wherein a spherical colloidal silica particle having a number average primary particle diameter of 30 to 80 nm and a triboelectric charge amount of ?50 to +300 ?C/g, and a fumed silica particle having a number average primary particle diameter of 5 to 25 nm are contained as the external additives, and wherein a content of the spherical colloidal silica particle is in the range from 0.3 to 2 parts by weight and a content of the fumed silica particle is in the range from 0.1 to 1 parts by weight with respect to 100 parts by weight of the colored resin particle.

Abstract: Coated phosphorescent pigments are provided which may be utilized in toner compositions. In embodiments, the phosphorescent pigment may be coated by a powder coating process. The large pigment particles may be dry blended with dried resin latex particles, thereby coating the pigment surface, followed by heating and shearing in a rotary kiln or extruder to melt the toner resin and fuse it to the pigment surface. The resulting coated particles may be utilized with other toners, in embodiments color toners, to provide phosphorescent images.

Abstract: To provide a developer and an image forming method with each of which a high-resolution, high-definition image can be stably obtained over a long time period irrespective of an environment. The present invention provides a developer including at least: toner particles each containing at least a binder resin; and a composite inorganic fine powder, the developer being characterized in that: the composite inorganic fine powder has a peak at a Bragg angle (2?±0.20 deg) of each of 32.20 deg, 25.80 deg, and 27.50 deg in a CuK? characteristic X-ray diffraction pattern; and the half width of the X-ray diffraction peak at a Bragg angle (2?±0.20 deg) of 32.20 deg is 0.20 to 0.30 deg.

Abstract: The toner of the present invention, comprising a colored resin particle and an external additive, wherein said external additive contains a silica fine particle (A) having a Dv50/Dv10 of 1.8 or more, in which Dv10 represents a particle diameter at which a volume cumulative total from small particle diameter side is 10% and Dv50 represents a particle diameter at which the mentioned volume cumulative total is 50%, a volume average particle diameter in the range from 0.1 to 1.0?, and a sphericity in the range from 1 to 1.3. The toner of the present invention cause less fog, and excellent resolution on the printed image, excellent in cleaning property, and cause less filming.

Abstract: A toner including toner particles including a binder resin, a colorant and a release agent, and an external additive including a first particulate inorganic material having a formula of MgxSiyOx+2y where each of x and y is an integer, and a number average secondary particle diameter of from 0.02 ?m to 2 ?m, wherein the first atomic ratio (Mg/Si)s in a surface portion of the first particulate inorganic material is not greater than (preferably less than) the second atomic ratio (Mg/Si)e in the entire first particulate inorganic material. Alternatively, a toner including toner particles including a binder resin and a colorant, and an external additive which includes a particulate inorganic material having a formula of MgxSiyOx+2y where each of x and y is an integer and which has a surface treated with a fatty acid.

Abstract: The present invention aims at providing non-magnetic toner which is excellent in fixing property and charge property and capable of inhibiting occurrence of scumming, as well as an image forming apparatus and a process cartridge using the non-magnetic toner. A non-magnetic toner comprising: a toner base particle which comprises a binding resin, and a colorant; and external additives, wherein a surface of the toner base particle contains at least a resin having at least silanol group, and the external additives contain at least particles composed of silicon oxide.

Abstract: In an image forming method including a charging step, an exposure step, a development step using a developing roll, a transfer step, a fixing step and a cleaning step of removing a toner remaining on the surface of a photosensitive member after the transfer step, the developing roll has a surface brightness of 30 to 220 and a surface roughness Rz of 1 to 20 ?m, the cleaning blade is a cleaning blade made of a polyurethane elastomer and having a peak value of at most 0.95, a peak temperature of ?15 to 10° C. and a width at half maximum of at least 25° C. in viscoelasticity tan ?, the toner has a volume average particle diameter of 4 to 10 ?m and an average circularity from 0.950 to 0.995, the charge level of the toner on the surface of the photosensitive member is 10 to 80 ?C/g in terms of an absolute value, and the pH of a water extract of the toner is 3 to 8.

Abstract: Hydrophobic inorganic fine particles are provided which: does not cause melt adhesion of toner to a photosensitive member and contamination of a contact charging member; imparts excellent flowability, charging performance and durability to toner even after the toner is stored in a high-temperature, high-humidity environment over a long time period; and does not cause dripping of toner and contamination with the toner. The hydrophobic inorganic fine particles are obtained by subjecting inorganic fine particles to surface treatment with silicone oil and then with a silane compound and/or a silazane compound, or by subjecting inorganic fine particles to surface treatment with a silane compound and/or a silazane compound in the presence of silicone oil, and further subjecting the inorganic fine particles thus surface-treated to surface treatment with silicone oil.

Abstract: A toner particle for use in electrostatic printing of a semiconducting electronic device, the particle comprising: a resin; and non-organic semiconductor particles dispersed in the resin.

Abstract: The present invention relates to a crystalline polyester for toner, obtained by a process comprising the step of polymerizing raw material monomers in the presence of a wax, wherein the crystalline polyester has a number-average molecular weight of from 3000 to 10000 and a weight-average molecular weight of from 150000 to 8000000. The toner containing the crystalline polyester of the present invention can be used, for example, for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method, and the like.

Abstract: A toner which combines excellent cleaning ability, image quality and durability, as well as a developer and an image forming method using the toner are provided. A toner comprising a toner base particle which comprises at least a binding resin and a colorant, and an external additive, wherein an external additive is a non-spherical amorphous silica particle and a major axis of the silica particle is 40 nm to 180 nm. An aspect wherein the non-spherical amorphous silica particle has a true specific gravity of 1.8 to 2.3 and the silica particle is hydrophobilized and a hydrophobilization degree is 40 or more, and an aspect wherein the non-spherical amorphous silica particle is produced by a dry system and a mass reduction rate is 5% by mass or less when the silica particle is heated from 30° C. up to 250° C. are preferable.

Abstract: The present invention provides an image forming apparatus capable of stably producing high quality images with time, without causing missing a central part of a thin line, however, with keeping an appropriate flowability of a toner. The toner used in the image forming apparatus is a toner which contains a binder resin, a colorant, and a laminar inorganic mineral in which at least part of an ion in layers is modified with an organic ion, the toner is granulated in an aqueous system, the volume average particle diameter Dv of the toner is in the range of 3.0 ?m<Dv<6.5 ?m, the aspect ratio of the toner is 0.81 to 0.89, and the surface of the toner is externally added with a plurality of types of fine particles.

Abstract: A toner for electrostatic charge image development has toner mother particles including a release agent, a colorant, and a binder resin including a crystalline resin, and an external additive to the toner mother particles including at least metatitanic acid and at least one selected from the group consisting of silicon oxide and fluoropolymer particles, and the addition weight ratio of the metatitanic acid to the at least one selected from the group consisting of silicon oxide and fluoropolymer particles is from 1:0.08 to 1:8.30 is provided.

Abstract: A developer has a molecular weight distribution of its tetrahydrofuran soluble portion measured by a gel permeation chromatography. In the molecular weight distribution, the main peak is in a range from 2×103 to 3×104 weight-average molecular weight (Mw), the shoulder peak is in a range from 200 to 500 Mw, and a half-value width of the main peak is equal to or less than 50000. A glass-transition temperature Tg of the developer is a range from 55° C. to 80° C.

Abstract: Environmentally friendly toner particles are provided which may, in embodiments, include a bio-based amorphous polyester resin, optionally in combination with another amorphous resin and/or a crystalline resin. Toner particles may, in embodiments, have a core-shell configuration, with the shell formed of the bio-based amorphous polyester resin, the amorphous polyester resin, the crystalline polyester resin, or combinations thereof.

Abstract: An electrostatic image developing toner includes a toner mother particle that contains a binder resin and a releasing agent; and an external additive that contains a zinc compound particle and a silica particle, wherein the zinc compound particle has a number average particle diameter of from about 2.0 ?m to about 10.0 ?m, the silica particle has a number average particle diameter of from about 60 nm to about 250 nm, the number of free zinc compound particles in all toner particles is from about 0.2% by number to about 1.0% by number, and the free zinc compound particle has an average circularity of about 0.6 or less.

Abstract: An electrophotographic toner including a latex, a coloring agent, and a release agent, wherein a difference between an average circularity of toner having a particle size of D16p or less (S16) and an average circularity of toner having a particle size of D50p or less (S50) is about 0.01 or less, wherein the circularity is measured using a flow particle image analyzer (FPIA), and the ratio of an area of wax to a total cross-sectional area of the toner having a particle size of D16p or less is about 8/100 or greater, and wherein the area is measured using a transmission electron microscope (TEM).

Abstract: A two-component developer containing a magenta toner and a magnetic carrier, wherein the magenta toner has the characteristics: (i) when the concentration of the magenta toner in a solution of the magenta toner in chloroform is represented by Cm (mg/ml) and the absorbance of the solution at a wavelength of 538 nm is represented by A538, a relationship between Cm and A538 satisfies the relationship of 2.00<A538/Cm<6.55; (ii) the lightness L* and chroma C* of the magenta toner determined in a powder state satisfy the relationships of 35?L*?45 and 60?C*?72; and (iii) the absolute value for the triboelectric charge quantity of the magenta toner measured by a two-component method using the magenta toner and the magnetic carrier is 50 mC/kg or more and 120 mC/kg or less.

Abstract: Toner particles, preferably emulsion aggregation toner particles, have improved relative humidity sensitivity through inclusion therein of silicate clay particles such as kaolin clay. The toner particles include a binder, preferably an acrylate-containing binder, at least one colorant, and silicate clay particles distributed in the binder. In a core-shell embodiment, the silicate particles are distributed in the core, the shell layer, or both. Developers of the toner in combination with carrier particles are also described.

Abstract: The object of the invention is to provide a toner enabling excellent transferring properties, cleanability, and fixability and forming a high-precision image without substantially degraded image quality even after printed on a number of sheets of paper. The invention also provides the toner-production method, an image forming apparatus, an image forming method, and a process cartridge. To this end, the present invention provides a toner which comprises toner-base particles containing a binder resin and a filler, and inorganic fine particles, in which the filler is included in a filler-layer in the vicinity of surfaces of the toner-base particles, the number average particle diameter of the primary particles of the inorganic fine particles is 90 nm to 300 nm, and the average circularity of the toner is 0.95.

Abstract: A positively charged developer for development of electrostatic images, comprising positively charged toner particles and an external additive, wherein the positively charged toner particles are colored resin particles composed of aggregated and fusion-bonded particles of fine binder resin particles and fine colorant particles and having a shape factor SF-1 of 115 to 150 and a shape factor SF-2 of 110 to 140, and the external additive is an external additive containing positively charged inorganic particles subjected to a hydrophobization treatment with an amino group-containing compound, and a production process thereof.

Abstract: To provide a toner containing at least a toner base containing a binder resin and a colorant, and an inorganic fine particle, wherein the inorganic fine particle contains a compound oxide expressed by the following Composition Formula (1): [M1]aSibOc??Composition Formula (1) where “M1” represents a metal element selected from Sr, Mg, Zn, Co, Mn and Ce, “a” and “b” each represents an integer of 1 to 9 and “c” represents an integer of 3 to 9, wherein an average primary particle diameter of the compound oxide is 0.02 ?m to 1.5 ?m, and an average secondary particle diameter of the compound oxide is 0.08 ?m to 3.5 ?m, where the secondary particle is an aggregate of the primary particles.

Abstract: A two-component developer containing a cyan toner and a magnetic carrier, wherein the cyan toner has the characteristics: (i) when the concentration of the cyan toner in a solution of the cyan toner in chloroform is represented by Cc (mg/ml) and the absorbance of the solution at a wavelength of 712 nm is represented by A712, a relationship between Cc and A712 satisfies the relationship of 2.00<A712/Cc<8.15; (ii) the lightness L* and chroma C* of the cyan toner determined in a powder state satisfy the relationships of 25.0?L*?40.0 and 50.0?C*?60.0; and (iii) the absolute value for the triboelectric charge quantity of the cyan toner measured by a two-component method using the cyan toner and the magnetic carrier is 50 mC/kg or more and 120 mC/kg or less.

Abstract: Disclosed are a toner for developing an electrostatic latent image and a method of preparing the same. The toner may include latex, a pigment and a releasing agent. The lowest crossover temperature of the toner at which the storage modulus (G?) and the loss modulus (G?) of the toner are substantially equal to each other may be in the range of about 65 to about 80° C. The weight average molecular weight (Mw) of the toner may be in the range of about 65,000 to about 75,000. The z-average molecular weight (Mz) of the toner may be in the range of about 110,000 to about 220,000.

Abstract: Disclosed are a toner for developing an electrostatic latent image and a method of preparing the toner. The toner may include a latex, a colorant and a releasing agent, and may further include sulfur (S), iron (Fe) and silicon (Si). The [S]/[Fe] ratio may be within the range between about 5.0×10?4 and about 5.0×10?2. The [Si]/[Fe] ratio may be within the range of between about 5.0×10?4 and about 5.0×10?2. [S], [Fe] and [Si] are the amounts of S, Fe and Si measured by X-ray fluorescence spectrometry, respectively.

Abstract: A developer of the present invention includes a toner and a carrier. The toner contains a charge control agent, and the carrier has on its surface a coating layer to which a charge control agent and electrically conductive particles are added. All of constituent elements of one of the charge control agent of the toner and the charge control agent of the carrier are contained in constituent elements of the other one of the charge control agents. With the configuration, the developer of the present invention is capable of stably maintaining a toner charge amount and outputting high-quality images for long periods.

Abstract: An electrophotographic toner includes toner parent particles containing a binder resin, a colorant and a charge control agent; and an external additive added to the surface of the toner parent particles. The toner further includes positively chargeable silica and polymer beads in addition to large particle diameter silica, small particle diameter silica and titanium oxides. Thus, the toner can maintain its charge quantity and distribution stably even during environmental changes and after long image printing times, thereby preventing the contamination of the non-image part and the filming.

Abstract: A developer includes a toner containing toner mother particles and external additives added to the toner mother particles. The toner mother particles contain at least a resin and a coloring agent. 1.5 to 3.0 weight parts of the external additives are added to 100 weight parts of the toner mother particles. The toner has a mean volume diameter in a range from 6.5 to 8.0 ?m, and a surface roughness Rzjis in a range from 75.3 to 236.9 nm as measured using a scanning probe microscope.

Abstract: A polymerized toner is provided. The polymerized toner comprises a reactive anionic surfactant having at least one reactive functional group. The reactive anionic surfactant is added simultaneously with a dispersant to prepare an aqueous dispersion or is added within 2 hour after a polymerization reaction of a monomer mixture is initiated in an aqueous dispersion. This simultaneous or rapid addition allows the reactive anionic surfactant to be dispersed on the surface of the toner particles. The reactive anionic surfactant is located over the entire surface of the toner particles to increase the surface charge density of the toner, achieving good charge stability and excellent imaging characteristics.

Abstract: A toner is provided. The toner includes toner particles, and silica particles and inorganic fine particles that are externally added to the toner particles, the inorganic fine particles having an average primary particle size smaller than that of the silica particles. The toner particles have a shape factor SF-1 of 130 or more and 140 or less, a shape factor SF-2 of 120 or more and 130 or less, and a volume average particle size of 5 ?m or more and 8 ?m or less. The silica particles have an average primary particle size of 80 nm or more and 150 nm or less, and an amount of water of 1.5% by weight or less. A particle size distribution of the silica particles is a logarithmic normal distribution, and a value of geometric standard deviation ?g of the particle size of the silica particles is less than 1.30.

Abstract: A toner is provided which has toner particles and a fine silica powder mixed by external addition to the toner particles. The toner has a weight average particle diameter of 4.0 to 9.0 ?m. The fine silica powder is subjected to hydrophobic treatment with dimethylsilicone oil, and has, in particle size distribution based on volume, a peak at which cumulative frequency is largest, in the measurement range of 0.02 ?m to 1,000.00 ?m; the cumulative frequency of 0.10 ?m to less than 1.00 ?m being 7.0% or less, and, the fine silica powder fulfills the following conditions: 1) A+B?93.0; 2) 0.45?A/B?6.00; and 3) the value of [(carbon content of the treated fine silica powder)/(BET specific surface area of fine silica powder before hydrophobic treatment)] is 0.030 or more to 0.055 or less.

Abstract: The present invention relates to controlling the mass flow of toner in an image forming device or a toner cartridge. The toner composition includes extra particulate additives including a conductive additive. The extra particulate additives may also include relatively small silica particles or relatively large silica.

Abstract: A toner, and an electrophotographic apparatus and an electrophotographic process cartridge using the toner are provided having excellent charge stability without adversely affecting electric properties of the toner even when used for a long period of time and having excellent image density stability without bringing about image deletion and blurring. The toner includes colored particles containing at least a binder resin and a colorant, and two or more external additives. At least one of the external additives includes hydrophobic treated mesoporous particles, and the mesoporous particles are inorganic particles of at least one type selected from the group consisting of silica, titanium oxide, alumina, cerium oxide, and strontium titanate.

Abstract: A paper sizing or coating composition is provided, which includes: a first binder resin, which is compatible with dry toner binder resin; a second binder resin, which is compatible with liquid toner binder resin, and which is different from the first binder resin; a first pigment, which has a BET surface area of from greater than zero to about 35 m2/g; and a second pigment, which has a BET surface area of about 35 m2/g or greater, and which is different from the first pigment. Recording sheets which include the composition, methods of making the composition and recording sheets, and methods for making an image are provided.

Abstract: A two-component developer and an image formation method for two-component development type are provided. With this developer and this method, even if toners have a small grain diameter and a high density of pigments for economizing the toner consumption, cracking and toner spent caused by the stress from carriers are suppressed, so that less deteriorated and stabler images can be obtained throughout a long time period. The two-component developer includes toner particles containing at least a binding resin and a pigment. A mean volume particle diameter of the toner particles is between 5.5 ?m and 7 ?m. A number percent of the toner particles with a mean volume particle diameter of 5 ?m or below, and a volume percent of the toner particles with a mean volume particle diameter between 8 ?m and 12.7 ?m, with respect to the total toner particles, respectively, are set to be within a predetermined range. Density of the pigment in the toner particles is between 8 weight percent and 20 weight percent.

Abstract: A toner for electrostatic image development containing (a) a toner matrix particle containing a resin binder, and (b) an external additive added to the toner matrix particles, wherein the resin binder contains a polyester A obtained by polycondensing an alcohol component and a carboxylic acid component containing isophthalic acid and/or an ester thereof, and wherein the external additive contains fine silica particles containing a metal or a metal oxide; and A method of forming fixed images including the step of applying the toner for electrostatic image development to an image-forming apparatus according to a non-contact fusing method. The toner for electrostatic image development of the present invention is suitably used in developing latent images formed in, for example, electrophotography, an electrostatic recording method, an electrostatic printing method, or the like.

Abstract: An embodiment of toner for electrostatic development may include toner base particles, and resin fine particles. Further, some embodiments may include external additives, such as hydrophobic silica. In some embodiments, the resin fine particles may include a polymer having an isobornyl group-containing acrylate monomer.

Abstract: A toner composition and method of providing such composition which may be used in a printer or printer cartridge. The composition may include toner particles mixed with silica particles having a primary particle size in the range of 30 nm to 60 nm present in the range of 0.1 to 2.0% by weight of the toner composition and silica particles having a primary particle size in the range of 60 nm to 150 nm present in the range of 0.1 to 2% by weight of the toner composition.

Abstract: When color images are printed on a substantially transparent substrate, such as a transparency film, or on a highly colored substrate, the color properties of image may be compromised. When color images are printed on a substantially transparent substrate, the images do not have the maximum possible color saturation because a large portion of the incident light is not reflected back. As a result, images appear to be dull and lower in contrast. When color images are printed on highly colored substrates, the color properties of the image are also influenced by the color of the substrate. In order to enable printing on such substrates, an opaque toner was developed which comprises predispersed inorganic filler with a refractive index of greater than 1.75.

Abstract: Hydrophobic inorganic fine particles are provided which: does not cause melt adhesion of toner to a photosensitive member and contamination of a contact charging member; imparts excellent flowability, charging performance and durability to toner even after the toner is stored in a high-temperature, high-humidity environment over a long time period; and does not cause dripping of toner and contamination with the toner. The hydrophobic inorganic fine particles are obtained by subjecting inorganic fine particles to surface treatment with silicone oil and then with a silane compound and/or a silazane compound, or by subjecting inorganic fine particles to surface treatment with a silane compound and/or a silazane compound in the presence of silicone oil, and further subjecting the inorganic fine particles thus surface-treated to surface treatment with silicone oil.

Abstract: A toner is provided which has toner particles and a fine silica powder mixed by external addition to the toner particles. The toner has a weight average particle diameter of 4.0 to 9.0 ?m. The fine silica powder is subjected to hydrophobic treatment with dimethylsilicone oil, and has, in particle size distribution based on volume, a peak at which cumulative frequency is largest, in the measurement range of 0.02 ?m to 1,000.00 ?m; the cumulative frequency of 0.10 ?m to less than 1.00 ?m being 7.0% or less, and, the fine silica powder fulfills the following conditions: 1) A+B?93.0; 2) 0.45?A/B?6.00; and 3) the value of [(carbon content of the treated fine silica powder)/(BET specific surface area of fine silica powder before hydrophobic treatment)] is 0.030 or more to 0.055 or less.

Abstract: Disclosed are an electrophotographic toner and a method of preparing the same. The electrophotographic toner includes latex; a colorant; and a releasing agent. The absolute value of a differential value of complex viscosity with respect to temperature, ( ? ? ? ? T ? ) of the electrophotographic toner in a temperature range of 100° C.-160° C. is in a range of about 0.03 to about 0.06, and complex viscosity (?) of the electrophotographic toner at 140° C. is in a range of about 1.0×102 Pa·s to about 6.0×102 Pa·s.

Abstract: A toner including stabilized magnetic single-crystal nanoparticles, wherein the value of the magnetic anisotropy of the magnetic nanoparticles is greater than or equal to 2×104 J/m3. The magnetic nanoparticle may be a ferromagnetic nanoparticle, such as FePt. The toner includes a magnetic material that minimizes the size of the particle, resulting in excellent magnetic pigment dispersion and dispersion stability, particularly in emulsion/aggregation toner processes. The smaller sized magnetic particles of the toner also maintains excellent magnetic properties, thereby reducing the amount of magnetic particle loading required in the toner.

Abstract: A two-component developer suppresses burying of an external additive into toner particles and a change in charging performance of a toner with time, and secures stable development performance. The two-component developer includes a toner and a carrier and is adjusted so that a rate of change ?A % in BET specific surface area A (m2/g) of the toner (=((A120?A1)/A1)×100) and a rate of change ?C % in charge quantity C (?C/g) of the carrier (=((C120?C1)/C1)×100) when a mixture of the toner and the carrier is stirred and mixed are both within 10 %. A1and A120 indicate BET specific surface areas of the toner when the mixture of the toner and the carrier is stirred and mixed for 1 minute and 120 minutes, and C1 and C120 indicate charge quantities of the carrier when the mixture is stirred and mixed for 1 minute and 120 minutes.

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 ? of a particle size distribution of the primary particle diameter satisfies a relation of: R/4???R, in which the R expresses the primary particle diameter, the oxide fine particles are substantially spherical having a circularity SF1 defined as equation (1) of 100 to 130 and a circularity SF2 defined as equation (2) of 100 to 125; SF1=(L2/A)×(?/4)×100??equation (1) SF2=(P2/A)×(1/4?)×100??equation (2), in the equations, “L” expresses the absolute maximum length of the oxide fine particles; “A” expresses a projected area of the oxide fine particles; and “P” expresses a maximum perimeter of the oxide fine particles.

Abstract: A developer used in an image forming apparatus, the developer containing: a toner, and a carrier that charges the toner, the toner containing a core toner, and an external additive that is added to a surface of the core toner, the core toner containing a colorant, a binder resin, a releasing agent, and a charge controlling agent containing Al and Mg, an amount of the charge controlling agent on the surface of the core toner being from 0.2 to 4.0 cps/eV in terms of a Mg amount measured by EDX, the core toner having a circularity of from 0.880 to 0.930, the external additive having a primary particle diameter of from 70 to 200 nm, an amount of the external additive being from 0.2 to 3.0% by weight based on the core toner.

Abstract: Toner compositions have a post-blended particulate additive which comprises aluminum oxide and aluminum hydroxide with, optionally, a third component such as silica or a wax, which is a tribo-charging additive which, upon tribo-charging of the toner particles, shifts the charge distribution in either the positive or negative direction. As well as providing toner compositions having adequate fluidity, the use of pre-extrusion charge-control additives can be avoided. There are also advantages, for example, in terms of charge distribution characteristics, stability of charge distribution, and avoidance of matting effects. Developer compositions are formed by admixture with suitable carrier particles.

Abstract: The invention relates to a developer for developing electrostatic images. The developer includes magnetic carrier particles at a loading of from 60 to 99 weight percent of the developer. Toner particles are at a loading of 1 to 40 weight percent of the developer. The toner particles include a resin core particle having an outer surface and 0.05 to 5 weight percent a first metal oxide powder is substantially fixed to the outer surface. The toner particles further include 0.05 to 2 weight percent of a second metal oxide powder that is substantially free to transfer between outer surface of the toner particles and an outer surface of the magnetic carrier surface.

Abstract: Carrier particles for forming a wiring circuit pattern by an electrophotographic developing method which are used for directly forming a circuit shape on an insulating layer, with any of a metal powder, an inorganic compound powder, or a mixed raw material powder thereof used as a toner powder for forming a circuit, the toner powder for forming a circuit being adhered to a surface of the carrier particles by electrostatic force and then transported to a surface of the insulating layer, wherein the carrier particles include a resin coated layer of an acrylic resin composition containing an amino-group-containing polymer on the surface of the carrier core material particles, the coating amount of the acrylic resin composition is 0.3 to 3.0% by weight based on a carrier core material weight of 100% by weight, and a shape factor SF-1 of the carrier core material particles is 100 to 110.

Abstract: According to an embodiment of the invention, an electrophotographic toner contains 100 parts by weight of a toner resin, from 0.01 to 10 parts by weight of a cyclodextrin compound, first silica having an average particle diameter of from 20 to 40 nm, and second silica having an average particle diameter of from 8 to 14 nm.