Abstract: An image forming method using a dry toner and exhibiting good quick-start and power economization characteristics is provided. The image forming method includes a heat-pressure fixing step using a rotatable electromagnetic induction heat-generation type heating member. The toner used therein is characterized by a moisture content of at most 3.00 wt. %, and viscoelasticities as represented by a storage modulus at 110° C. of G′ (110° C.) and a storage modulus at 140° C. of G′ (140° C.) satisfying: G′ (110° C.)≦1.00×106 dN/m2, and G′ (140° C.)≧7.00×103 dN/m3.

Abstract: A magnetic toner exhibiting stable performances under various environmental conditions is formed of toner particles each comprising at least a binder resin and iron oxide dispersed therein. Relative to the dry specific gravity (A) of the magnetic toner, the magnetic toner is characterized by a specific gravity distribution of toner particle fractions obtainable through wet sedimentation and including: at most 15 wt. % of a fraction having a specific gravity of above (A)×1.000 and at most (A)×1.025, 0.1-20 wt. % of a fraction having a specific gravity of above (A)×0.975 and at most (A)×1.000, at least 30 wt. % of a fraction having a specific gravity of above (A)×0.950 and at most (A)×0.975, 0.1-20 wt. % of a fraction having a specific gravity of above (A)×0.925 and at most (A)×0.950, and at most 15 wt. % of a fraction having a specific gravity of above (A)×0.900 and at most (A)×0.925.

Abstract: A magnetic toner includes: magnetic toner particles each comprising at least a binder resin and magnetic toner, and inorganic fine powder. The magnetic toner has an average circularity of at least 0.970, and a magnetization of 10-50 Am2/kg at a magnetic field of 79.6 kA/m. The magnetic powder comprises at least magnetic iron oxide. The magnetic toner particles retain carbon in an amount of A and iron in an amount of B at surfaces thereof as measured by X-ray photoelectron spectroscopy, satisfying: B/A<0.001. The binder resin comprises a resin formed by polymerization of a monomer comprising at least styrene monomer. The magnetic toner has a residual styrene monomer content of less than 300 ppm, and contains at least 50% by number of toner particles satisfying a relationship of: D/C≦0.

Abstract: A toner is formed of toner particles each comprising a binder resin and iron oxide particles dispersed therein. The toner particles are characterized by uniform but non-surface-exposed dispersion of the iron oxide particles within the toner particles as represented by (i) a carbon content (A) and an iron content (B) giving a ratio B/A<0.001 at surfaces of the toner particles as measured by X-ray photoelectron spectroscopy, (ii) an average circularity of at least 0.970, and (iii) at least 50% by number of toner particles satisfying D/C≦0.02, wherein C denotes a projection area-equivalent circular diameter of each toner particle and D denotes a minimum distance of iron oxide particles from a surface of the toner particle, based on a sectional view of the toner particle as observed through a transmission electron microscope (TEM).

Abstract: In an image forming system, an image-bearing member having a photoconductor layer comprising an Si-based non-single crystal material is charged at a relatively low potential of 250 to 600 volts by a contact charging member in the presence of electroconductive fine powder. An electrostatic latent image formed on the image-bearing member is developed with a magnetic toner which includes magnetic toner particles comprising at least a binder resin and a magnetic iron oxide, and inorganic fine powder and electroconductive fine powder present at the surface of the magnetic toner particles. The magnetic toner has a weight-average particle size of 3-10 &mgr;m and an average circularity of 0.950 to 0.995, and contains 0.05 to 3.00 % of isolated iron-containing particles.

Abstract: A magnetic toner capable of exhibiting stable chargeability regardless of environmental change is formed of magnetic toner particles each comprising at least a binder resin, an iron oxide and a sulfur-containing polymer, and inorganic fine powder blended with the magnetic toner particles. The magnetic toner is also provided with good developing performance and high transferability by satisfying a weight-average particle size (D4) of 3-10 &mgr;m, an average circularity of at least 0.970, and a magnetization of 10-50 Am2/kg (emu/g) at a magnetic field of 79.6 kA/m (1000 oersted). The magnetic toner is further characterized in that the magnetic toner particles retain carbon in an amount of A and iron in an amount of B at surfaces thereof as measured by X-ray photoelectron spectroscopy, satisfying: B/A<0.001, and the magnetic toner contains at least 50% by number of magnetic toner particles satisfying a relationship of D/C≦0.

Abstract: An image forming method using a dry toner and exhibiting good quick-start and power economization characteristics is provided. The image forming method includes a heat-pressure fixing step using a rotatable electromagnetic induction heat-generation type heating member. The toner used therein is characterized by a moisture content of at most 3.00 wt. %, and viscoelasticities as represented by a storage modulus at 110° C. of G′ (110° C.) and a storage modulus at 140° C. of G′ (140° C.) satisfying: G′ (110° C.)≦1.00×106 dN/m2, and G′ (140° C.)≧7.00×103 dN/m3.

Abstract: A magnetic toner includes: magnetic toner particles each comprising at least a binder resin and magnetic toner, and inorganic fine powder. The magnetic toner has an average circularity of at least 0.970, and a magnetization of 10-50 Am2/kg at a magnetic field of 79.6 kA/m. The magnetic powder comprises at least magnetic iron oxide. The magnetic toner particles retain carbon in an amount of A and iron in an amount of B at surfaces thereof as measured by X-ray photoelectron spectroscopy, satisfying: B/A<0.001. The binder resin comprises a resin formed by polymerization of a monomer comprising at least styrene monomer. The magnetic toner has a residual styrene monomer content of less than 300 ppm, and contains at least 50% by number of toner particles satisfying a relationship of: D/C≦0.

Abstract: A magnetic toner comprising magnetic toner particles containing at least a binder resin, a magnetic material containing a magnetic ion oxide, and a release agent. The magnetic toner has a weight-average particle diameter of from 3 &mgr;m to 10 &mgr;m, a magnetization intensity (saturation magnetization) of from 10 Am2/kg to 50 Am2/kg (emu/g) under application of a magnetic field of 79.6 kA/m (1,000 oersteds), an average circularity of 0.970 or more, a ratio of weight-average particle diameter to number-average particle diameter, of 1.40 or less, iron and an iron compound which stand liberated from the magnetic toner particles at a liberation percentage of from 0.05% to 3.00%, and a resin component having a tetrahydrofuran-insoluble matter in an amount of from 3% by weight to 60% by weight. Also disclosed is an image-forming method making use of the magnetic toner.

Abstract: A toner has toner particles and an external additive. The toner particles have a weight-average particle diameter of from 4 &mgr;m to 9 &mgr;m. The external additive has (i) first, small-particle-diameter hydrophobic fine silica particles (A) having a BET specific surface area of from 100 m2/g to 350 m2/g, having been treated with a silane, (ii) second, large-particle-diameter hydrophobic fine silica particles (B) having a BET specific surface area of from 15 m2/g to 80 m2/g, having been treated with a silicone oil, and (iii) fine alumina particles (C) having a BET specific surface area of from 50 m2/g to 150 m2/g.

Abstract: An electrophotographic toner is formed of toner particles each comprising at least a binder resin, a colorant and a release agent, and a low-crystalline aromatic metal compound present at surfaces of the toner particles. The toner has an average circularity of at least 0.955, and the low-crystalline aromatic metal compound has an X-ray diffraction characteristic free from peaks exhibiting a measurement intensity of at least 10000 cps and a half-value half-width of at most 0.3 deg. in a range of measurement angles 2&thgr; of 6 to 40 deg. Because of the low crystallinity, the aromatic metal compound is uniformly applied onto the toner particle surfaces to stabilize the chargeability and transferability of the toner.

Abstract: A toner is comprised of toner particles containing at least a binder resin and a colorant, and an external additive fine powder. The toner particles have a specific circularity distribution and a specific particle size distribution. The external additive fine powder has an inorganic fine powder having as primary particles a specific number-average particle length, and a non-spherical inorganic fine powder formed by coalescence of particles and having a specific shape factor and a specific number-average particle length.

Abstract: A toner is disclosed which has toner particles and an external additive. The toner has (a) in circularity distribution of particles measured with a flow type particle image analyzer, an average circularity of from 0.920 to 0.995, containing particles with a circularity of less than 0.950 in an amount of from 2% by number to 40% by number; and (b) a weight-average particle diameter of from 2.0 .mu.m to 9.0 .mu.m as measured by Coulter method. The external additive has, on the toner particles, at least (i) an inorganic fine powder (A) present in the state of primary particles or secondary particles and having an average particle length of from 10 m.mu.m to 400 m.mu.m and a shape factor SF-1 of from 100 to 130 and (ii) a non-spherical inorganic fine powder (B) formed by coalescence of a plurality of particles and having a shape factor SF-1 of greater than 150. Also, a two-component developer and an image forming method, using the toner, are disclosed.

Abstract: In an image forming method for forming multi-color images or full-color images, first to third or fourth toners are used, and the amount of cross-linking agent contained in each of the toners becomes larger in the order of the toners laid on a recording sheet. Each of the toners has a color different from the others, the color selected from yellow, cyan, magenta and black.

Abstract: A toner for developing an electrostatic image is constituted by at least toner particles and an additive. The toner particles have a shape factor SF-1 of 100-160, a phase factor SF-2 of 100-140 and a weight-average particle size of 4-10 .mu.m as measured by a Coulter counter. The toner contains particles having circle-equivalent diameters in a range of 0.6-2.0 .mu.m and satisfying the following conditions (i)-(iii): (i) a first value C.sub.1 of 3-50% by number as measured by a flow particle image analyzer after application of a ultrasonic wave of 20 kHz for 5 min., (ii) a second value C.sub.2 of 2-40% by number as measured by the flow particle image analyzer after application of a ultrasonic wave of 20 kHz for 1 min., and (iii) a value C of 105-150 obtained according to the following equation: C=(C.sub.1 /C.sub.2).times.100 The toner is effective in improving image-forming characteristics in a continuous image formation on a large number of sheets.