Abstract: A ferrite sintered body is composed of an oxide containing, as metal element, at least Fe and Zn and at least one selected from Ni, Cu and Mn. This sintered body contain Fe of 42 to 50 mol % in terms of Fe2O3, and Zn of 15 to 35 mol % in terms of ZnO. When the Zn concentration in the sintered body interior is taken to be 1, the Zn concentration in the surface vicinity is 0.8 to 12. This increases the surface resistance of the ferrite sintered body and lowers its core loss.

Abstract: An Ni—Cu—Zn-based ferrite material contains TiO2 alone as an additive in an amount of 0.1 wt %<x?4.0 wt % in which x denotes a content of the TiO2 and unavoidable impurities. The principal components thereof are 43.0 to 49.8 mol % of Fe2O3, 4.0 to 13.0 mol % of CuO, 5 to 35 mol % of ZnO and the balance of NiO.

Abstract: An NiCuZn-base ferrite of the invention comprises as main components an iron oxide in an amount of 45.0 to 49.0 mol % on Fe2O3 basis, an copper oxide in an amount of 5.0 to 14.0 mol % on CuO basis and a zinc oxide in an amount of 1.0 to 32.0 mol % on ZnO basis with a nickel oxide accounting for the rest mol % on NiO basis. With respect to the main components, a bismuth oxide is contained in an amount of 0.25 exclusive to 0.40% by weight on Bi2O3 basis, and a tin oxide is contained in an amount of 1.00 to 2.50% by weight on SnO2 basis. The invention ensures a leap upward in direct-current bias characteristics.

Abstract: A ferrite core comprising a sintered oxide containing at least 48.6 to 53.9 mol % of Fe on Fe2O3 basis, 12.3 to 35.2 mol % of Ni on NiO basis and 16.4 to 37.0 mol % of Zn on ZnO basis as metal elements, and contains a crystal phase comprising two or more kinds of solid solutions selected from NiFe2O4, ZnFe2O4 and FeFe2O4, wherein full width at half maximum of a diffraction peak, of crystal phase of which diffraction angle 2? is in a range from 34.6 to 36.4° as measured by X-ray diffraction analysis using Cu—K? beam, is 0.4° or less.

Abstract: A composite magnetic material contains first magnetic particles made of a first magnetic material and second magnetic particles made of a second magnetic material, the first and second magnetic particles being mixed with each other. A frequency characteristic of the first magnetic material is different from that of the second magnetic material. The first and second magnetic particles are mixed so that, at a frequency of an intersecting point between a first curve representing a frequency characteristic of a real part of a complex magnetic permeability of the first magnetic material and a second curve representing a frequency characteristic of a real part of a complex magnetic permeability of the second magnetic material, a value of a real part of a complex magnetic permeability of the composite magnetic material is larger than a value of the intersecting point.

Abstract: A magnetic device and method for making it involve a magnetic device specifically constructed of grains in a matrix. The matrix may be cement or plaster. The grains have an average diameter that is greater than their magnetic domains. The device may be applied to shielding applications for frequencies ranging from 100 kHz to 10 GHz. The shielding may be applied to walls of a building, consumer products such as magnetic disks, and the like. The grains may be any ferromagnetic material, including ferrite.

Abstract: An Mn—Zn ferrite includes base components of 44.0 to 49.8 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, 0.8 mol % or less Mn2O3, and the remainder consisting of MnO, and contains 0.20 (0.20 excluded) to 1.00 mass % CaO as additive. Since the Mn—Zn ferrite contains less than 50.0 mol % Fe2O3 and a limited amount (0.8 mol % or less) of Mn2O3, an abnormal grain growth does not occur even if CaO content is more than 0.20 mass %, and a high electrical resistance can be gained thereby realizing an excellent soft magnetism in a high frequency band such as 1 MHz.

Abstract: A Mn—Zn based ferrite having a main component comprised of 51 to 54 mol % of an iron oxide in Fe2O3 conversion, 14 to 21 mol % of a zinc oxide in ZnO conversion and the rest of a manganese oxide, wherein a content (? [ppm]) of cobalt oxide in a CoO conversion with respect to 100 wt % of the main component satisfies a relation formula below. Relation formula: Y1???Y2??(1) Note that Y1 and Y2 are expressed by the formulas below and CoO>0 [ppm]. Y1=(?0.13·B2+1.5·B?15.6A+850)/(0.0003·B+0.0098)?233??(2) Y2=(?0.40·B2+4.6·B?46.7A+2546)/(0.0003·B+0.0098)+1074??(3) The A and B in the above Y1 and Y2 are A=Fe2O3 (mol %) and B=ZnO (mol %).

Abstract: An oxide magnetic material is prepared by wet molding in a magnetic field a slurry containing a particulate oxide magnetic material, water and a polyhydric alcohol having the formula: Cn(OH)nHn+2 wherein n is from 4 to 100 as a dispersant. By improving the orientation in a magnetic field upon wet molding using water, an oxide magnetic material having a high degree of orientation, typically an anisotropic ferrite magnet, is obtained at a high rate of productivity. The method is advantageous from the environmental and economical standpoints.

Abstract: A composite magnetic material contains first magnetic particles made of a first magnetic material and second magnetic particles made of a second magnetic material, the first and second magnetic particles being mixed with each other. A frequency characteristic of the first magnetic material is different from that of the second magnetic material. The first and second magnetic particles are mixed so that, at a frequency of an intersecting point between a first curve representing a frequency characteristic of a real part of a complex magnetic permeability of the first magnetic material and a second curve representing a frequency characteristic of a real part of a complex magnetic permeability of the second magnetic material, a value of a real part of a complex magnetic permeability of the composite magnetic material is larger than a value of the intersecting point.

Abstract: A method for manufacturing single crystal ceramic powder is provided. The method includes a powder supply step for supplying powder consisting essentially of ceramic ingredients to a heat treatment area with a carrier gas, a heat treatment step for heating the powder supplied to the heat treatment area at temperatures required for single-crystallization of the powder to form a product, and a cooling step for cooling the product obtained in the heat treatment step to form single crystal ceramic powder. The method provides single crystal ceramic powder consisting of particles with a very small particle size and a sphericity being 0.9 or higher.

Abstract: Briefly, in accordance with one embodiment of the present invention, a process for making a magnetic composite which comprises providing a polymeric resin and a magnetic powder, the magnetic powder having a mean particle size with a value for standard deviation that is less than the value for the mean particle size of the said magnetic powder, the said magnetic composite being made by mixing said magnetic powder with said polymeric resin and molding the said mixture into a desired shape and a size and said magnetic composite having a magnetic permeability between 30 and 50. In another embodiment the present invention is a composition for a magnetic composite comprising a polymeric resin and a magnetic powder, the said powder having a mean particle size with a value of standard deviation that is less than the value of the mean particle size of the magnetic powder, wherein said magnetic composite has a magnetic permeability between about 30 and about 50.

Abstract: A carrier core material containing at least one metal oxide (MLO) having a melting point of not higher than 1000° C. and at least one metal oxide (MHO) having a melting point of not lower than 1800° C., wherein the metal (MH) for constituting the metal oxide (MHO) has an electrical resistivity of not less than 10−5 &OHgr;·cm. Also disclosed is a two-component developing agent comprising a coated carrier, which comprises the carrier core material coated with a resin, and toner particles. Further disclosed is an image forming method comprising developing an electrostatic latent image formed on a photosensitive member with the two-component developing agent using an alternating electric field. The carrier core material and the coated carrier have high magnetization and are free from occurrence of leakage of electric charge over a wide range of electric field from low electric field to high electric field.

Abstract: A high frequency magnetic material includes a Y or M type hexagonal ferrite, wherein the hexagonal ferrite is expressed by the composition formula (1-a-b)(Ba1-xSrx)O.aMeO.bFe2O3, where Me is at least one selected from the group consisting of Co, Ni, Cu, Mg, Mn and Zn, 0.205≦a≦0.25, 0.55≦b≦0.595, 0≦x≦1, and 2.2≦b/a<3. A high frequency circuit element includes magnetic layers and internal electrode layers, wherein the high frequency circuit element is a sintered compact and the magnetic layers include the high frequency magnetic material.

Abstract: A Ni type ferrite material of a low magnetic loss. The Ni type ferrite material is formed by adding MnO2 in an amount of 0.1 to 10 mol % to a ferrite material of a composition containing Fe2O3 in 40 to 50 mol %, ZnO in 20 to 33 mol %, CuO in 2 to 10 mol %, and NiO in the remainder. Such Ni type ferrite material is adapted for use in a coil component as a core material because of a smaller magnetic loss in comparison with a prior material, and has a high electric resistance to allow direct coil winding on the core, thereby realizing reduction in both size and weight of the coil component.

Abstract: An Mn—Zn ferrite includes base components of 44.0 to 49.8 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, 0.8 mol % or less Mn2O3, and the remainder consisting of MnO, and contains 0.20 (0.20 excluded) to 1.00 mass % CaO as additive. Since the Mn—Zn ferrite contains less than 50.0 mol % Fe2O3 and a limited amount (0.8 mol % or less) of Mn2O3, an abnormal grain growth does not occur even if CaO content is more than 0.20 mass %, and a high electrical resistance can be gained thereby realizing an excellent soft magnetism in a high frequency band such as 1 MHz.

Abstract: A ferrite fine powder having a mean particle size of 0.1 to 30 &mgr;m and made of spherical single-crystal particles. The ferrite fine powder has superior physical properties and excellent magnetic properties desirable for use as a raw material for a dust core of coils, transformers, etc. The powder is prepared by forming a solution or suspension containing a compound or compounds of at least one of the metals forming the ferrite into fine droplets, and thermally decomposing the droplets at elevated temperatures.

Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.

Abstract: A low temperature co-fired ferrite-ceramic (FECERA) composite consisting of two different dielectric materials (Ceramic and Ferrite) can be used to make a diversification combination filter component by the process of a multi-layer passive component, so that the combination filter component can prevent the function of electromagnetic interference (EMI) and has an excellent electromagnetic couple effect.

Abstract: Black magnetic iron oxide particles having an average particle diameter of 0.05 to 1.0 &mgr;m have a three-phase structure comprising: a core portion containing at least one metal element other than Fe selected from the group consisting of Mn, Zn, Cu, Ni, Cr, Cd, Sn, Mg, Ti, Ca and Al in an amount of 0.1 to 10% by weight based on whole Fe contained in the particles; a surface coat portion containing at least one metal element other than Fe selected from the group consisting of Mn, Zn, Cu, Ni, Cr, Cd, Sn, Mg, Ti, Ca and Al in an amount of 0.1 to 10% by weight based on whole Fe contained in the particles; and an intermediate layer disposed between the core portion and the surface coat portion, containing substantially none of the metal elements other than Fe.

Abstract: The Mn—Zn ferrite of the present invention contains basic components of 44.0 to 50.0 mol % (50.0 mol % is excluded) Fe2O3, 4.0 to 26.5 mol % ZnO and the remainder MnO, and has a real part &egr;′ of complex relative permittivity of 20,000 or less at 1 kHz and 50 or less at 1 MHz, thereby maintaining initial permeability in a wide frequency band, showing a low stray capacitance with a coil provided, and ensuring an excellent impedance in a wide frequency band. And a coil using the Mn—Zn ferrite as a magnetic core is also provided.

Abstract: Provided is magnetic ferrite powder in which a peak intensity ratio of Z phase (M3Me2Fe24O41: M=one or more kinds of alkaline-earth metal, Me=one or more kinds from Co, Ni, Mn, Zn, Mg and Cu) of hexagonal ferrite is 30% or higher in X-ray diffraction and a peak value of a grain size distribution is in a range from 0.1 &mgr;m to 3 &mgr;m.

Abstract: There can be provided an NiCuZn-based ferrite material containing an iron oxide, a copper oxide, zinc oxide and a nickel oxide in predetermined amounts as main components and a bismuth oxide, a silicon oxide, magnesium oxide and a cobalt oxide in predetermined amounts as additional components. Due to the predetermined amounts of the additional components, the ferrite material has an extremely good temperature characteristic (a change in permeability along with a change in temperature is small), a high quality coefficient Q and high strength.

Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.

Abstract: This invention relates to the formula and preparation method for a multi-layer chip inductor material used in very high frequencies. The main composition of this material is planar hexagonal soft magnetic ferrite, and ingredient is low temperature sintering aid. Preparation method is a synthetic method of solid phase reaction. The sintering aid is prepared by secondary doping. By the process of ball grinding, drying, pre-calcining, ball grinding, drying, granulating, forming, sintering, and so forth, very high frequency inductor material of superior quality is obtained, realizing low temperature sintering under a temperature lower than 900° C. This invention is of low cost, high performance, suitable for multi-layer chip inductors at very high frequencies of 300M-800 MHz.

Abstract: A Ni type ferrite material of a low magnetic loss. The Ni type ferrite material is formed by adding MnO2 in an amount of 0.1 to 10 mol % to a ferrite material of a composition containing Fe2O3 in 40 to 50 mol %, ZnO in 20 to 33 mol %, CuO in 2 to 10 mol %, and NiO in the remainder. Such Ni type ferrite material is adapted for use in a coil component as a core material because of a smaller magnetic loss in comparison with a prior material, and has a high electric resistance to allow direct coil winding on the core, thereby realizing reduction in both size and weight of the coil component.

Abstract: The subject invention includes a composite material comprising a ferroelectric material and a ferromagnetic material having a loss factor (tan &dgr;) for the composite material which includes a dielectric loss factor of the ferroelectric material and a magnetic loss factor of the ferromagnetic material. The composite material achieves the loss factor of from 0 to about 1.0 for a predetermined frequency range greater than 1 MHz. The ferroelectric material has a dielectric loss factor of from 0 to about 0.5 and the ferromagnetic material has a magnetic loss factor of from 0 to about 0.5 for the predetermined frequency range. The ferroelectric material is present in an amount from 10 to 90 parts by volume based on 100 parts by volume of the composite material and the ferromagnetic material is present in an amount from 10 to 90 parts by volume based upon 100 parts by volume of the composite material such that the amount of the ferroelectric material and the ferromagnetic material equals 100 parts by volume.

Abstract: A fluorescent or luminous composition, comprising a multilayered film-coated powder having at least two coating films on a base particle, and a fluorescent or luminous substance; the composition, wherein at least one layer of the coating films contains the fluorescent or luminous substance; a genuine/counterfeit discrimination object, in which the fluorescent or luminous composition; and a genuine/counterfeit discrimination method, comprising recognizing fluorescence or luminescence by irradiating, with a light, the genuine/counterfeit discrimination object.

Abstract: There is provided a sintered body at least 80% of which is constituted of a Y-type hexagonal ferrite. The sintered body contains, as main components, a cobalt oxide, a copper oxide, an iron oxide and AO (AO is at least one of BaO or SrO) in predetermined amounts in mol %, more preferably contains MO (MO is at least one of NiO, ZnO or MgO) in a predetermined amount in mol % in addition to the above components, and also contains, as additional components, bismuth oxide (Bi2O3), borosilicate glass, borosilicate zinc glass or bismuth glass in predetermined amounts in wt %. Thus, a sintered body which exhibits good magnetic properties and is usable up to a high frequency band ranging from several hundred megahertz to gigahertz, contains as few hetero phases other than a Y-type hexagonal ferrite as possible and can be calcined at a temperature of not higher than 1,000° C., particularly about 900° C., and a high-frequency circuit component using the sintered body can be provided.

Abstract: In a composition for a plastic magnet, containing an Nd—Fe—B based alloy powder and a ferrite magnetic material powder mixed to a resin material, the Nd—Fe—B based alloy powder has particle sizes distributed in a range of 100 to 400 &mgr;m, and the ferrite magnetic material powder has an average particle size of approximately 1 &mgr;m. The weight ratio of the Nd—Fe—B based alloy powder to the ferrite magnetic material powder is in a range of 30:70 to 70:30. Further, the ratio of the total weight of the Nd—Fe—B based alloy powder 2 and the ferrite magnetic material powder 3 to the weight of the resin material is in a range of 90:10 to 80:20. Thus, in a plastic magnet 1 formed using the composition, peripheries of particles of the Nd—Fe—B based alloy powder 2 are surrounded by particles of the ferrite magnetic material powder 3 and the resin material.

Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.

Abstract: A high frequency magnetic material ceramic composition including materials having the general formula (Ca, A)zCuxB8−x−zO12 is prepared. A represents Y and/or at least one element selected from the rare earth elements excluding Y; B represents metal elements which are different from A and include at least Fe and V. x has a value of 0.002<x<0.2; and z is a value of 3.0<z≦3.09. The Ca/V ratio is 2.0<Ca/V≦2.4. A irreversible circuit component containing center electrodes electrically insulated from each other in a ferrite member made of the high frequency magnetic material ceramic is provided.

Abstract: A ferrite with a high permeability and a high dielectric constant is introduced. Raw material powders, such as TiO2, Fe2O3 and the oxide of Mn, Ni, Cu, Mg, Li or Zn is prepared and combined in the proportion Tix(MFe2O4+2x/y)y, where x+y=1 and 0<×<1. M is any one of a mixture of metals selected from Mn, Ni, Cu, and Zn. The ratio between x and y can be adjusted according to practical needs to obtain ferrites with different permeabilities and dielectric constants. The ferrite can simultaneously be a magnetic material and a dielectric material in an electronic element. This can avoid the possible drawbacks due to sintering of two different materials in the prior art.

Abstract: The subject invention includes a composite material comprising a ferroelectric material and a ferromagnetic material having a loss factor (tan &dgr;) for the composite material which includes a dielectric loss factor of the ferroelectric material and a magnetic loss factor of the ferromagnetic material. The composite material achieves the loss factor of from 0 to about 1.0 for a predetermined frequency range greater than 1 MHz. The ferroelectric material has a dielectric loss factor of from 0 to about 0.5 and the ferromagnetic material has a magnetic loss factor of from 0 to about 0.5 for the predetermined frequency range. The ferroelectric material is present in an amount from 10 to 90 parts by volume based on 100 parts by volume of the composite material and the ferromagnetic material is present in an amount from 10 to 90 parts by volume based upon 100 parts by volume of the composite material such that the amount of the ferroelectric material and the ferromagnetic material equals 100 parts by volume.

Abstract: Ni—Cu—Zn based oxide magnetic materials, in that not only the internal conductor is stabilized at very low firing temperatures, but also the characteristics in the high frequency zones of 100 MHz or higher are excellent. The oxide magnetic materials comprises, Fe2O3: 35.0 to 51.0 mol %, CuO: 1.0 to 35 mol %, NiO: 38.0 to 64.0 mol %, ZnO: 0 to 10.0 mol % (including 0%) and Ca: 0.3 wt % or lower (not including 0%), and, optionally, CoO: 0.7 wt % or lower.

Abstract: There is provided a sintered body at least 80% of which is constituted of a Y-type hexagonal ferrite. The sintered body contains, as main components, a cobalt oxide, a copper oxide, an iron oxide and AO (AO is at least one of BaO or SrO) in predetermined amounts in mol %, more preferably contains MO (MO is at least one of NiO, ZnO or MgO) in a predetermined amount in mol % in addition to the above components, and also contains, as additional components, bismuth oxide (Bi2O3), borosilicate glass, borosilicate zinc glass or bismuth glass in predetermined amounts in wt %. Thus, a sintered body which exhibits good magnetic properties and is usable up to a high frequency band ranging from several hundred megahertz to gigahertz, contains as few hetero phases other than a Y-type hexagonal ferrite as possible and can be calcined at a temperature of not higher than 1,000° C., particularly about 900° C., and a high-frequency circuit component using the sintered body can be provided.

Abstract: This invention relates to the formula and preparation method for a multi-layer chip inductor material used in very high frequencies. The main composition of this material is planar hexagonal soft magnetic ferrite, and ingredient is low temperature sintering aid. Preparation method is a synthetic method of solid phase reaction. The sintering aid is prepared by secondary doping. By the process of ball grinding, drying, pre-calcining, ball grinding, drying, granulating, forming, sintering, and so forth, very high frequency inductor material of superior quality is obtained, realizing low temperature sintering under a temperature lower than 900° C. This invention is of low cost, high performance, suitable for multi-layer chip inductors at very high frequencies of 300M-800 MHz.

Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.

Abstract: A high frequency magnetic material ceramic composition including materials having the general formula (Ca, A)zCuxB8-x-zO12 is prepared. A represents Y and/or at least one element selected from the rare earth elements excluding Y; B represents metal elements which are different from A and include at least Fe and V. x has a value of 0.002<x<0.2; and z is a value of 3.0<z≦3.09. The Ca/V ratio is 2.0<Ca/V≦2.4. A irreversible circuit component containing center electrodes electrically insulated from each other in a ferrite member made of the high frequency magnetic material ceramic is provided.

Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.

Abstract: A magnetic composition comprised of cobalt ferrite nanoparticles dispersed in an ionic exchange resin.

Abstract: This invention provides a Mn—Zn ferrite which has a high electrical resistance and can sufficiently satisfy the use in a high frequency region exceeding 1 MHz. This invention further provides a production process of the Mn—Zn ferrite in which mixed powder whose components are adjusted so as to have a basic component composition containing 44.0 to 50.0 mol% Fe2O3, 4.0 to 26.5 mol % ZnO, 0.1 to 8.0 mol % one or two from TiO2 and SnO2 and the remainder consisting of MnO, and further to contain 0.01 to 2.00 mass % one or more of CoO, NiO, and MgO as additive is pressed, then sintered and cooled in the air or in an atmosphere containing some amount of oxygen.

Abstract: A ferrite material based on nickel, copper and zinc has the following formula: NixZnyCuzCo&egr;Fe2±&dgr;O4 in which: x+y+Z+&egr;=1±&dgr; &dgr;≦0.05 0.04≦&egr; 0.05≦z≦0.35 A material of this kind has the advantage of showing reduced losses.

Abstract: Granule for forming ferrite is provided by mixing powders of ferrite raw material, polyvinyl alcohol as a binder and polyethylene glycol added as plasticizer and having molecular weight being 1000 to 6000, and forming granules.

Abstract: The present invention relates to methods of producing synthetic crystals (typically minerals) or comparable inorganic compounds by reactions of metal salts and metal oxyhydroxides under near-critical, critical or supercritical solvent conditions, avoiding thereby many of the difficulties associated with conventional solid state or wet chemistry synthesis. The metal oxyhydroxides are typically divalent or trivalent metals and the preferred solvent is typically (but not exclusively) water under near-critical, critical or supercritical conditions. The crystals so produced have a controlled particle size distribution. The crystals produced by the present invention also have morphologies with favorable properties for compaction into green bodies for subsequent sintering into near-net-shapes, approaching maximum theoretical densities. Avoidance of noxious by-products is another advantage of the present synthetic methods.

Abstract: Provided are a method for preparing an Ni—Cu—Zn ferrite powder having excellent sinterability at a lower temperature, and a method for producing a laminated chip inductor from the above ferrite powder. The method for preparing the ferrite powder is a method for the preparation of a soft magnetic ferrite powder composed of Fe, Ni, Cu and Zn as main components, and comprises the step of allowing an organic additive to be present in a slurry containing a calcined product of a starting powder and water, wherein the organic additive is an organic compound having a hydroxyl group and a carboxyl group or a neutralization salt or lactone thereof, or the organic additive is an organic compound having a hydroxymethylcarbonyl group, an organic compound having an enol type hydroxyl group dissociable as an acid or a salt thereof.

Abstract: The present invention can provide a MgCuZn-based ferrite sintered compact which is constituted by having as substantial main component compositions 7.5 to 23.0 mole % of magnesium oxide, 7.0 to 20.0 mole % of copper oxide, 19.0 to 24.2 mole % of zinc oxide and 48.5 to 50.3 mole % of ferric oxide, and the average particle diameter of the ferrite sintered compact is in a range of 1.10 to 7.30 &mgr;m while the standard deviation &sgr; of the size distribution is in a range of 0.60 to 10.00, resulting in the ferrite sintered compact which has a high impedance with a frequency of not less than 50 MHz and is capable of efficiently cutting of radiant noise by selecting inexpensive materials.

Abstract: To use a media agitating mill of a wet internal circulation type when grinding materials, and offer oxide magnetic materials and coils in which influences of ZrO2 and Y2O3 mixing when using partially stabilized zirconia as media beads are improved. The magnetic materials and coils are characterized in that Fe2O3, ZnO, NiO and CuO are main components, and Y2O3, ZrO2 and Bi2O3 are contained with respect to these main components, where an amount of Y2O3 is 0.007 to 0.028 wt % for the total amount, an amount of ZrO2 is 0.12 to 0.55 wt % therefor and an amount of Bi2O3 is 0.03 to 10.12 wt % for the same.

Abstract: Magnetic ceramic compositions include a Fe compound, a Zn compound, a Ni compound and a Cu compound as primary components, and also includes a bismuth compound and a cobalt compound as additive components. The primary component composition ratio (Fe2O3, ZnO, NiO+CuO) represented by molar percent of Fe2O3, ZnO, and (NiO and CuO), is in the region enclosed by point A (48.0, 0.5, 51.5), point B (48.0, 1.5, 50.5), point C (45.5, 4.0, 50.5), point D (44.0, 4.0, 52.0), and point E (44.0, 0.5, 55.5) in a ternary diagram. About 8.0 to 14.0 molar percent of the Cu compound is included in 100 molar percent of the primary components as Fe2O3, ZnO, NiO, and CuO. About 0.25 to 1.0 part by weight of the bismuth compound as Bi2O3 and about 0.25 to 3.0 parts by weight of the cobalt compound as Co3O4 with respect to 100 parts by weight of the primary components are included.

Abstract: The present invention relates to a method for preparing multi-purpose magnetized and sintered ceramics, comprising the steps of adding water to a mixture of Maek-Ban Stone and soft sericite, stirring and maturing at a room temperature, sintering, and irradiating with a magnetic field. The ceramics obtained by the present invention produce various effects such as keeping food fresh, deodorization and purification.