Abstract: The present application relates to a composition, a 3D printing method using the same, and a three-dimensional shape comprising the same, and provides a composition capable of embodying a precise formation of a three-dimensional shape using a ceramic material and a uniform curing property of the three-dimensional shape.

Abstract: A magnetic toner is provided, which has a magnetic toner particle containing a binder resin, a wax, and a magnetic body, wherein, when Dn is a number-average particle diameter of the toner, CV1 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?0.500 to +0.500, and CV2 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?1.500 to ?0.500, a relationship CV2/CV1?1.00 is satisfied; an average brightness of the toner in the range of Dn ?0.500 to +0.500 is 30.0 to 60.0; and when, in a cross section of the toner observed using a transmission electron microscope, which is divided with a square grid having a side of 0.8 ?m, coefficient of variation CV3 of an occupied area percentage for the magnetic body is 40.0 to 80.0%.

Abstract: The present invention relates to a process for producing a toner for development of electrostatic images, including step (1): subjecting a polyhydric alcohol component and a polycarboxylic acid component to polycondensation reaction in the presence of a hydroxy group- or carboxy group-containing hydrocarbon wax (W1) to obtain a non-crystalline resin (A) containing a constitutional component derived from the hydrocarbon wax (W1) and also containing a polyester moiety; step (2): dispersing the non-crystalline resin (A) obtained in the step (1) in an aqueous medium to obtain an aqueous dispersion of resin particles (X); step (3): aggregating the resin particles (X) obtained in the step (2) in an aqueous medium in the presence of a crystalline polyester (B) to obtain aggregated particles; and step (4): coalescing the aggregated particles obtained in the step (3).

Abstract: An object of the present invention is to provide a carrier in which decrease in specific gravity is achieved and a volatile organic compound (VOC) is reduced and to provide an electrophotographic developer using the carrier. There is provided a carrier including a core material coated with a resin, the core material including a magnetic component and a nonmagnetic component, wherein the sum total of volatile organic compounds is 1 ppb or more and 1.5 ppm or less. There is also provided an electrophotographic developer using the carrier.

Abstract: A method for applying flame treatments to a print surface on an object in an inkjet printer includes activating a hydrogen torch within the inkjet printer to generate a flame through a nozzle of the hydrogen torch and operating an actuator to move at least one of the print surface or the nozzle in a predetermined direction to apply the flame from the nozzle to the print surface. The method further includes adjusting a rate of fuel flow to the nozzle of the hydrogen torch to change a thermal output level of the flame with reference to a change in distance between the nozzle of the hydrogen torch and the print surface during the operating of the actuator.

Abstract: A composite charge control agent for use in electrostatic imaging comprises porous, inorganic core particles of at least 0.08 microns in diameter, impregnated with 2% to 50% by weight of one or more charge control chemicals and up to 50% by weight of one or more additional compounds such as a polymer, a wax, a dye, or other organic chemicals.

Abstract: Ferrite particles have, as a main component, a material represented by a composition formula MxFe3?xO4 (where M is at least one type of metal selected from a group made of Mg, Mn, Ca, Ti, Cu, Zn, Sr and Ni, 0<x<1), where the maximum height Rz of the particles falls within a range of 1.40 ?m to 1.90 ?m, and the degree of distortion Rsk of the particles falls within a range of ?0.25 to ?0.07. In this way, when the ferrite particles are used as the carrier of an electrophotographic image forming apparatus, even if an image formation speed is increased, the occurrence of a failure is reduced for a long period of time.

Abstract: The toner comprising a toner particle containing a binder resin and a colorant, an iron oxide particle and an organic-inorganic composite fine particle, wherein the organic-inorganic composite fine particle comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which is exposed at surface of the organic-inorganic composite fine particle; the organic-inorganic composite fine particle has convexes derived from the inorganic fine particles, and wherein: a coverage ratio of the surface of the organic-inorganic composite fine particle with the inorganic fine particle is 20-70%; and the content of the iron oxide particle present on a surface of the toner particle is 0.1-5.0 mass % based on the mass of the toner particle.

Abstract: A method for making an impact-absorptive material is introduced. The method involves mixing silicon dioxide (SiO2) particles, polydimethylsiloxane (PDMS), and an appropriate amount of an additive, allowing the mixture to settle until tiny bubbles in the mixture are evenly distributed, thereby forming a colloidal solution raw material, adding a crosslinking agent to the colloidal solution raw material to form a colloidal solution plastic material, filling a die with the colloidal solution plastic material, heating the colloidal solution plastic material in the die such that it takes shape and forms an effective impact absorbing material, quickly and at low costs, for use in physical education, medicine, transportation, and safety-enhancing equipment.

Abstract: Provided are a toner and a two-component developer each of which: shows a small fluctuation in charge quantity and a small fluctuation in image density even under a high-temperature and high-humidity environment; and does not cause any member contamination even after endurance and hence can stably output an image. The toner and the two-component developer each have a feature in that positively chargeable strontium titanate fine particles are added to toner particles having fixed thereto negatively chargeable silica fine particles.

Abstract: The present invention relates to a method for producing a suspension of agglomerates of magnetic alkoxysilane-coated metal nanoparticles, wherein an aqueous suspension of magnetic metal nanoparticles is incubated with alkoxysilane, wherein the incubation is carried out essentially in the absence of an organic solvent. The present invention further relates to suspension of agglomerates of magnetic alkoxysilane-coated metal containing nanoparticles obtainable by the method of the present invention and to a composition comprising agglomerates of magnetic alkoxysilane-coated metal nanoparticles, wherein the agglomerates have an average size of 30 to 450 nm, preferably of 50 to 350 nm and especially of 70 to 300 nm as determined by light scattering.

Abstract: Provided are a toner containing at least a binder resin and a colorant, the toner having a specific hue angle and an absorbance at a specific wavelength in reflectance spectrophotometry, and a full-color image-forming method involving the use of the toner, the method including the steps of: forming an electrostatic image on a charged electrostatic image bearing member; developing the formed electrostatic image with the toner to form a toner image; transferring the formed toner image onto a transfer material; and fixing the transferred toner image to the transfer material to form a fixed image.

Abstract: A method for the reduction of caking of excess liquid developer dispersion that remains present on the surface of a member after transfer of liquid developer dispersion from one member to another member in a digital printing apparatus, comprising the step of adding a dispersing composition to the excess liquid developer dispersion, wherein the dispersing composition comprises a dispersing agent.

Abstract: There is provided an electrostatic image developing toner less likely to cause image degradation even when used for a long period, by controlling CCA particles present on surfaces of toner particles and thereby keeping an amount of tribocharge generated between the toner and a magnetic carrier or the like constant. A charge control agent composition for external addition for controlling charge amount of toner particles includes: at least two types of carrier particles different in average particle size of primary particles; and a charge control agent (CCA), and an electrostatic image developing toner is constituted of a mixture of toner particles and the aforesaid charge control agent composition for external addition.

Abstract: Provided is a magnetic toner which exhibits a high degree of blackness and high tinting strength, and in which scraping of a toner carrying member surface by the magnetic toner is not caused, and image defects such as fogging and tailing are suppressed. A magnetic toner comprising a magnetic toner particle that contains a binder resin and a magnetic iron oxide particle, wherein, the number-average particle diameter of the magnetic iron oxide particle ranges from 0.05 ?m to 0.15 ?m, and a relationship between the number-average particle diameter (?m) of the magnetic iron oxide particle and the specific surface area (m2/g) of the magnetic iron oxide particle satisfies Expression (1) below. [Number?average particle diameter]×[specific surface area]?1.

Abstract: To obtain a toner which has excellent charge rise and stability, tends to have a sharp charge distribution, has excellent pigment dispersion properties, exhibits no disarray in an image even during a high-speed copying operation, and can stably output high-resolution images. A toner comprising toner particle containing a binder resin, a colorant, resin PA, and resin PB, wherein the resin PA has unit A represented by Formula (1), the resin PB has unit B represented by Formula (2), a content “a” of the unit A in the toner particle is 2.00 ?mol/g or more, and a molar ratio b/a of the content “a” and a content “b” of the unit B in the toner particle is 0.10 or more and 10.00 or less.

Abstract: An electrostatic image developer includes a toner containing an external additive having a volume-average particle size of about 80 to 400 nm and an average circularity of about 0.7 to 0.85. The developer is used in an image forming apparatus including an image-carrying member having a top surface layer containing fluorocarbon resin particles, and a developer-carrying member that faces the image-carrying member and carries an electrostatic image developer, in which a value obtained by dividing the amount of developer on the developer-carrying member [g/m2] by a shortest distance between the image-carrying member and the developer-carrying member [?m] is about 0.8 to 1.8, and a peripheral velocity ratio of the developer-carrying member to the image-carrying member is about 1.5 to 5.0 or the developer-carrying member moves in a direction opposite to the image-carrying member in a facing portion.

Abstract: The present invention provides a magnetic carrier for an electrophotographic developer which has an excellent durability and a stable charging property and is free from occurrence of spent toner thereonto, and a two-component system developer comprising the magnetic carrier for an electrophotographic developer and a toner. The present invention relates to a core material of a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 ?m, a resin index of the spherical composite particles being within the range of 35 to 80%, and a magnetic carrier obtained by coating a surface of respective particles of the magnetic carrier core material with a resin.

Abstract: A method and system for printing documents with one or more embedded security features is provided. Security features are embedded in the document by co-printing magnetic and non-magnetic toner on a receiver before fixation by a fixing station. The combination of magnetic and non-magnetic toners in the image results in image elements that easily show alteration or are undetectable by visual means.

Abstract: The positively chargeable magnetic toner contains a binder resin and a magnetic powder with a specified octahedral shape, in which a frictional charged amount of the magnetic powder with a ferrite carrier, and a particle number of the magnetic powder exposed on a surface of the positively chargeable magnetic toner per 1 ?m2 area of the positively chargeable magnetic toner in an electron microscope image, are defined as values within predetermined ranges.

Abstract: Provided is a two-component developer having excellent developing performance and little change in image concentration, and achieving long-term suppression of image defects such as transfer failure and fogging. Provided is a two-component developer containing a magnetic carrier and a toner, wherein the magnetic carrier has magnetic carrier particles comprising a silicone resin B coated on the surfaces of filled core particles in which pores of porous magnetic core particles are filled with a silicone resin A, the silicone resin A is a silicone resin cured in the presence of a non-metal catalyst or without a catalyst, while the silicone resin B is a silicone resin cured in the presence of a metal catalyst having titanium or zirconium, and the toner contains a binder resin, a release agent and a colorant, and has an average circularity of 0.940 or more.

Abstract: Provided is a magnetic toner capable of preventing electrostatic offset while attaining a high image quality by a high speed machine. The magnetic toner comprises magnetic toner particles, each of which contains a binder resin and a magnetic material, and a fine inorganic powder, in which the binder resin contains a polyester unit, and the magnetic toner has a dielectric loss factor at 40° C. and 100 kHz of 0.40 pF/m or more but 1.00 pF/m or less and a dielectric loss factor at 150° C. and 100 kHz of 0.50 pF/m or more but 4.00 pF/m or less.

Abstract: Provided is a magnetic toner capable of providing a stable image by suppressing sleeve contamination even under a high-temperature and high-humidity environment and under a normal-temperature and low-humidity environment and further suppressing large-particle fogging caused after the toner is left alone for a week. The magnetic toner contains toner particles, each of which contains a binder resin and a magnetic iron oxide particle, in which the binder resin has a polyester unit, the toner has i) a dielectric loss factor at 40° C. and 100 kHz of 0.50 pF/m or more but 0.90 pF/m or less, and ii) a true specific gravity of 1.50 g/cm3 or more but 1.85 g/cm3 or less.

Abstract: A porous ferrite core material for an electrophotographic developer wherein the apparent density thereof is 1.5 to 1.9 g/cm3, the shape factor SF-2 thereof is 101 to 110 and the magnetization as measured with a VSM at 1K·1000/4?·A/m is 40 to 60 Am2/kg, a resin-coated ferrite carrier for an electrophotographic developer obtained by coating the surface of the porous ferrite core material with a resin, and an electrophotographic developer using the ferrite carrier.

Abstract: A carrier for electrostatic image development, and a developer, an image formation method and an image formation apparatus using the carrier. The carrier is carrier particles. When the carrier particles each have a coating layer on a magnetic particle, the carrier has a total energy amount of 1500 to 3000 mJ. When the carrier particles each have a coating layer on a magnetic powder-dispersed particle, the carrier has a total energy amount of 1000 to 1500 mJ. The total energy amount is measured with a powder rheometer at a tip end speed of a rotor of 100 mm/s and a helix angle of the rotor of ?5°. The total energy amount is a value of a portion of the carrier in a measurement container which portion is contained in the region between the packed surface of the carrier and a surface disposed under the packed surface by 70 mm.

Abstract: A magnetic toner has magnetic toner particles, each of the magnetic toner particles containing a binder resin and a magnetic material, and an inorganic fine powder. The magnetic material is prepared by treating the surface of magnetic iron oxide with a silane compound. When the magnetic iron oxide is dispersed in an aqueous solution of hydrochloric acid and dissolved until the dissolution proportion of the iron element reaches 5% by mass based on the total amount of the iron element contained in the magnetic iron oxide, the amount of silicon eluted by that point of time is 0.05% by mass or more and 0.50% by mass or less based on the magnetic iron oxide. The magnetic material has a moisture adsorption amount per unit area of 0.30 mg/m2 or less.

Abstract: The present invention relates to a toner composition for forming a masking pattern for use e.g. in connection with a method of building up a three-dimensional body from a large number of mutually connected layers of powder particles that are bonded to each other using radiant heat. The toner composition consists of powder particles that arc able to withstand a temperature of at least 200° C. without sticking together. It also relates to a developer that comprises the toner composition and carrier particles and a method in connection with the production of a volume body by using a toner composition or a developer according to the invention.

Abstract: The present disclosure provides carriers for use with toner compositions. In embodiments, a carrier may include a core, having a dry powder polymer coating. In embodiments, the coating may also include a colorant, such as carbon black. Processes for coating such carriers with the dry powder polymer coatings are also provided.

Abstract: Provided is a magnetic toner capable of providing a stable image by suppressing sleeve contamination even under a high-temperature and high-humidity environment and under a normal-temperature and low-humidity environment and further suppressing large-particle fogging caused after the toner is left alone for a week. The magnetic toner contains toner particles, each of which contains a binder resin and a magnetic iron oxide particle, in which the binder resin has a polyester unit, the toner has i) a dielectric loss factor at 40° C. and 100 kHz of 0.50 pF/m or more but 0.90 pF/m or less, and ii) a true specific gravity of 1.50 g/cm3 or more but 1.85 g/cm3 or less.

Abstract: The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical magnetic composite particles comprising a phenol resin as a binder and ferromagnetic iron oxide particles bonded to each other through the phenol resin, wherein the spherical magnetic composite particles have a ten-point mean roughness Rz of 0.3 to 2.0 ?m. The magnetic carrier for an electrophotographic developer according to the present invention exhibits an excellent durability against peeling-off and abrasion of coating resins formed thereon and a high stability to mechanical stress exerted onto the carrier, is free from occurrence of spent toner, can be stably held over a long period of time without occurrence of fogging and unevenness in density of toner images, and can keep high-quality images with an excellent gradation for a long period of time.

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: The present invention relates to black magnetic iron oxide particles comprising magnetite as a main component, wherein when the black magnetic iron oxide particles are molded into a tablet shape, an electric resistance value of the tablet in an alternating current electric field is controlled to produce an impedance of not less than 2×106 ?cm as measured in a characteristic frequency range thereof. The black magnetic iron oxide particles according to the present invention can provide a toner capable of exhibiting a good charging performance and a uniform charging property under the high-temperature and high-humidity conditions, so that when developing an electrostatic latent image therewith, it is possible to obtain toner images having a high resolution or definition, and further the use of heavy metal elements in the black magnetic iron oxide particles can be minimized.

Abstract: The object of the present invention is to provide a magnetic toner enabling an image with high image density and excellent image reproducibility to be obtained, which is excellent in fluidity, charging stability, and charging uniformity, even for long-term use, and also enabling an image whose fogging, ghost, and scattering are suppressed to be obtained. The magnetic toner has at least a binder resin and a magnetic material, where, the magnetic material is an magnetic iron oxide whose dielectric breakdown voltage of the magnetic material is 160 to 1600 V/cm, and the dielectric loss tangent (tan ?) of the magnetic toner at 100 kHz and 40° C. is 2.0×10?3 to 1.0×10?2.

Abstract: A method and system for printing documents with one or more embedded security features is provided. Security features are embedded in the document by co-printing magnetic and non-magnetic toner on a receiver before fixation by a fixing station. The combination of magnetic and non-magnetic toners in the image results in image elements that easily show alteration or are undetectable by visual means.

Abstract: An object of the present invention is to provide a toner excellent in ability to prevent electrostatic offset and fixation tailing. Provided is a toner including toner particles each containing at least a binder resin, a wax, and a magnetic iron oxide, and inorganic fine particles, in which the magnetic iron oxide contains at least a Ti component, an Al component, an Si component, and an Fe component; and the each component has some particular characteristics.

Abstract: A magnetic toner has magnetic toner particles, each of the magnetic toner particles containing a binder resin and a magnetic material, and an inorganic fine powder. The magnetic material is prepared by treating the surface of magnetic iron oxide with a silane compound. When the magnetic iron oxide is dispersed in an aqueous solution of hydrochloric acid and dissolved until the dissolution proportion of the iron element reaches 5% by mass based on the total amount of the iron element contained in the magnetic iron oxide, the amount of silicon eluted by that point of time is 0.05% by mass or more and 0.50% by mass or less based on the magnetic iron oxide. The magnetic material has a moisture adsorption amount per unit area of 0.30 mg/m2 or less.

Abstract: A toner which can efficiently induce high-frequency magnetic induction heating by Neel relaxation and/or Brown relaxation is provided. A toner including a core particle containing a thermoplastic polymer material and superparamagnetic ferrite fine particles having a particle diameter of less than 100 nm which adhere to the surfaces of the core particle is manufactured by directly forming the superparamagnetic ferrite fine particles having a particle diameter of less than 100 nm on the surfaces of the core particle so that the superparamagnetic ferrite fine particles having a particle diameter of less than 100 nm are not in contact with each other. As a result, the toner is prevented from being scattered due to the influence of a magnetic field, so that a high quality image is formed.

Abstract: In the formation of images by a two-component development system, provided is a magnetic carrier that can be used to output an image which has sufficient density, in which few white spots are present in a low-density portion located near the boundary between a high-density region and a low-density region, and in which the low-density portion has good graininess. The magnetic carrier contains magnetic carrier particles each of which has resin and a magnetic particle. The magnetic particle contains ferrite phases and phases comprising a perovskite-structured compound. The ferrite phases and phases comprising a perovskite-structured compound are combined.

Abstract: A magnetic toner is disclosed having magnetic toner particles containing a binder resin and a magnetic iron oxide. The magnetic toner has a specific saturation magnetization and a specific residual magnetization in ascertain magnetic field. The binder resin includes a polyester component polymerized with an aromatic carboxylic acid titanium compound as a catalyst.

Abstract: A magnetic toner is disclosed including magnetic toner particles containing at least a binder resin and a magnetic powder. The magnetic powder contains a specific amount of phosphorus elements, and a specific amount of silicon elements, based on the iron element, with the ratio of the phosphorous element to the silicon elements being in a specific range, and has a specific volume-average particle diameter, a specific saturation magnetization in a specific magnetic field, and a specific residual magnetization. The magnetic toner can realize high image density and reduce fog and spots around line images regardless of environmental variation, and is superior in durability, and besides, can achieve small toner consumption.

Abstract: Provided is a two-component developer containing: a magnetic carrier obtained by coating a magnetic core with a resin; and toner, in which: the magnetic core contains at least a ferrite component and at least one kind of an oxide selected from the group consisting of SiO2 and Al2O3; the content of the oxide is 4.0 mass % or more and 40.0 mass % or less with respect to the magnetic core; the magnetic core has a specific resistance of 5.0×104 ?·cm or more and 5.0×108 ?·cm or less at the time of the application of 1,000 V/cm; the magnetic carrier has an intensity of magnetization in 79.6 kA/m of 40.0 Am2/kg or more and 65.0 Am2/kg or less, and a residual magnetization after the application of an external magnetic field of 79.6 kA/m of 3.0 Am2/kg or less; and the toner has a weight-average particle diameter (D4) of 3.0 gin or more and 10.0 ?m or less and an average circularity of 0.940 or more and 0.990 or less.

Abstract: A developing apparatus is provided which can suppress a fluctuation in image density in a discontinuous printing mode provided with a pause period. The developing apparatus includes a developer for developing an electrostatic latent image on a photosensitive drum, a developer bearing member for carrying and conveying the developer and a developer layer thickness-regulating unit placed close to the developer bearing member for regulating the amount of the developer carried and conveyed by the developer bearing member, the developer layer thickness-regulating unit being. As the developer, a negatively chargeable, one-component, magnetic toner is used having magnetic toner particles containing a binder resin and a magnetic iron oxide particle, and has a specific saturation magnetization, specific weight-average particle diameter and specific composition.

Abstract: A positively chargeable developer is provided which is capable of providing stable image quality without causing any image defect even in long-term use. The developer includes at least positively chargeable toner particles each containing at least a binder resin and magnetic iron oxide, silica and an inorganic fine powder. A unconfined yield strength at a major consolidation stress of 5 kPa of the developer is in the range of 0.1 to 2.5 kPa, and a unconfined yield strength at a major consolidation stress of 20 kPa of the developer is in the range of 2.5 to 5.5 kPa.

Abstract: A magnetic carrier is provided which uses a toner having high coloring power and enables development to be performed at low electric field intensity and can form high quality images while keeping gradation characteristics. The magnetic carrier includes magnetic carrier particles including at least porous magnetic core particles and a resin. The electric field intensity just before the break-down of the magnetic carrier is 1,300 V/cm or more and 5,000 V/cm or less.

Abstract: The invention relates to an image forming media composition including an infrared reflecting pigment. The infrared reflecting pigment may be one that substantially absorbs light in the visible spectrum of about 400-700 nanometers and reflects greater than about 5.0% of light within the wavelength of about 700-2500 nanometers. The infrared reflecting pigment may therefore be combined with pigments such as carbon black in a toner formulation and provide the ability to control toner thickness level within a device such as a toner patch sensor.

Abstract: An object of the present invention is to provide a toner excellent in ability to prevent electrostatic offset and fixation tailing. Provided is a toner including toner particles each containing at least a binder resin, a wax, and a magnetic iron oxide, and inorganic fine particles, in which the magnetic iron oxide contains at least a Ti component, an Al component, an Si component, and an Fe component; and the each component has some particular characteristics.

Abstract: It is contemplated to provide irregular shaped ferrite carrier which has a lower resistance, a high specific surface area, a low specific gravity and a longer operational life, and an electrophotographic developer comprising the ferrite carrier which prevents the toner scattering, has a high image density, and is responsive to high-speed and color imaging. The irregular shaped ferrite carrier is characterized in that the carrier particles are irregular shaped, and 40 percent by number or more of the particles have a rock candy sugar shape and/or an oyster shell shape, and that the shape factor (SF-1=R2/S×?/4×100, wherein R is a maximum length and S is a projected area.) is 140 to 250, and the distribution width (?) is 60 or less.

Abstract: Magnetic toner involves magnetic powder 1 having the particle shape of an octahedron 2 that is a convex polyhedron surrounded by eight triangles as a basis, each of the vertexes and edges of the octahedron being in a curved surface shape, and having a portion 3 that can be taken as a straight line on the outer periphery of its projected image. Therefore, the magnetic toner is superior in both two contradictory properties, that is the property of making it easy for a charging amount to quickly rise as well as improving the charging amount and the property of making it difficult for charge-up to occur, thereby making it possible to form a good image under a wide environment. In an image forming method, an electrostatic latent image is developed into a toner image by a magnetic one-component jumping developing method using the magnetic toner.

Abstract: A magnetic toner having magnetic toner particles containing at least a binder resin and a magnetic material, wherein, in the test of dissolution level of the magnetic material, the dissolution percentages S3 (% by mass), S15 (% by mass) and S30 (% by mass), and the dissolution level proportion Sc satisfy the following expressions: 0.5?S3?10, 40?S15?80, 1.2?Sc[=(S15?S3)/(S30?S15)]?10; and the magnetic toner has a dielectric loss factor (tan ?) at 25° C. and at a frequency 1.0×104 Hz, within the range of from 2.0×10?3 or more to 1.5×10?2 or less.

Abstract: An object of the present invention is to suppress the adhesion of a carrier to an image bearing member and the generation of a flaw in the surface layer of the image bearing member, and to improve the dot reproducibility of an electrostatic latent image, and soon. The object is achieved by a two-component developer containing a magnetic carrier, which contains resin-containing magnetic particles, in which the packed bulk density ?1 is 0.80 to 2.40 and ?1/?2 (?2 represents true density) is 0.20 to 0.42 of the porous magnetic core particles, and a specific resistance of the porous magnetic core particles, an average breaking strength of the magnetic carrier and a toner surface tension constant in a 45-vol % aqueous solution of methanol measured by a capillary suction time method fall into the specific range, respectively.