Abstract: Provided is a developer capable of providing an excellent image without causing a charging failure even after a long-term and repeated use.

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: There is provided a swing type multi-way switch in which light irradiated from a light source built therein sufficiently illuminates substantially all over the rear surface of an operation knob. The switch comprises: a box-like operation knob; a square frame-shaped holder disposed in the inside of the operation knob; a case having an outer square tube-like member and an inner square tube-like member coaxially formed; and a base plate on which a light source and a plurality of switch elements are to be mounted. The operation knob is rotatably supported by the holder disposed in the inside of the operation knob, and the holder is rotatably supported by the inner square tube-like member of the case by a second axis for rotating movement orthogonal to the axis for rotating movement of the operation knob.

Abstract: Outer ends of link members supported to a case and having their inner ends coupled to each other are coupled to a slider. A membrane sheet and a pusher are disposed one after the other on the slider, and a knob having molded therewith a surface sheet is fixed to the slider. On a bottom plate are mounted a tactile push-button switch and a light source. No matter which press area is depressed, the slider is uniformly translated by the link mechanism to actuate the push-button switch. The link mechanism, the slider, the membrane sheet except conductor portions, and the pusher are formed of a light transmitting material.

Abstract: A carrier for electrophotography and a two component type developer using the carrier. The carrier is composed of magnetic particles of a magnetic ferrite component represented by Formula: (Fe2O3)X(MnO)Y(A)Z. An image forming method is also disclosed which uses the two component type developer.

Abstract: A magnetic toner is formed of magnetic toner particles each comprising a binder resin, an iron oxide, a sulfur-containing polymer, and inorganic fine powder blended with the magnetic toner particles, the toner having a weight-average particle size (D4) of 3-10 &mgr;m, and either (a) 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), or (b) toner particles which retain carbon in an amount of A and iron in an amount of B at surfaces thereof, satisfying: B/A<0.001, and containing at least 50% by number of magnetic toner particles of D/C≦0.02, wherein C represents a particle projection area-equivalent circle diameter and D represents a minimum distance between a surface of the magnetic toner particle and iron oxide particles contained therein.

Abstract: A toner is comprised of a binder resin, a colorant and a wax. The binder resin has a polycarbonate resin in an amount of from 0.1% by weight to 50.0% by weight and a resin other than the polycarbonate resin in an amount of from 50.0% by weight to 99.9% by weight, based on the weight of the binder resin. In molecular weight distribution as measured by gel permeation chromatography of tetrahydrofuran-soluble matter, the toner contains in an amount of 15.0% by weight or less based on the weight of the toner a component which has in its structure a repeating unit of the polycarbonate resin and is contained in components having a molecular weight of 1,000 or less.

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: A magnetic toner comprising magnetic toner particles containing at least a binder resin, a magnetic material containing a magnetic iron 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: Magnetic particles for charging means disposed in contact with an electrophotographic photosensitive member for charging the electrophotographic photosensitive member based on a voltage applied thereto are provided as particles of a ferrite component represented by the following formula (1): (Fe2O3)X(A)Y(B)Z  (1), wherein A denotes at least one metal oxide component selected from the group consisting of Li2O, MnO and MgO, B denotes at least one metal oxide component different from A; X, Y and Z denote numbers representing mol ratios and satisfying the following conditions: 0.2<X<0.95, 0.01<Y<0.5, X+Y≦1, and 0≦Z<0.79. The magnetic particles show an excellent charging performance, particularly in injection charging, without causing a difficulty, such as soiling or pinhole leakage of the photosensitive member.

Abstract: A carrier for electrophotography and a two component type developer using the carrier. The carrier is composed of magnetic particles of a magnetic ferrite component represented by Formula: (Fe2O3)X(MnO)Y(A)Z. An image forming method is also disclosed which uses the two component type developer.

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: A carrier for electrophotography and a two component type developer using the carrier.

Abstract: A toner is comprised of a binder resin, a colorant and a wax. The binder resin has a polycarbonate resin in an amount of from 0.1% by weight to 50.0% by weight and a resin other than the polycarbonate resin in an amount of from 50.0% by weight to 99.9% by weight, based on the weight of the binder resin. In molecular weight distribution as measured by gel permeation chromatography of tetrahydrofuran-soluble matter, the toner contains in an amount of 15.0% by weight or less based on the weight of the toner a component which has in its structure a repeating unit of the polycarbonate resin and is contained in components having a molecular weight of 1,000 or less.

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 carrier for electrophotography and a two component type developer using the carrier. The carrier is composed of magnetic particles of a magnetic ferrite component represented by Formula: (Fe2O3)X(MnO)Y(A)Z. An image forming method is also disclosed which uses the two component type developer.

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.