Abstract: A coil component including a core part and a coil part formed by winding a conductor in a coil form, in which the coil part is inside of the core part. The core part has a center pole part positioned in an area surrounded by an inner diameter of the coil part. The center pole part includes a first center pole part and a second center pole part each having different predetermined configurations, or the center pole part includes soft magnetic metal particles having predetermined deflection angles and aspect ratios.

Abstract: A coil device, in which an air-core coil of a cylindrical shape is buried in a core including a magnetic powder and a resin, showing, CV value of the below described cross sectional areas, SA1 to SA5, 0.55 or less, when an outer diameter of the air-core coil is “a1”, an inner diameter of the same is “a2”, and a distance between a surface of the core perpendicular to a direction of winding axis and an end of the air-core coil in the direction of winding axis is “h”, is provided. The coil device is superior in DC superimposing characteristic while suppressing the magnetic saturation.

Abstract: A coil device, in which an air-core coil of a cylindrical shape is buried in a core including a magnetic powder and a resin, showing, CV value of the below described cross sectional areas, SA1 to SA5, 0.55 or less, when an outer diameter of the air-core coil is “a1”, an inner diameter of the same is “a2”, and a distance between a surface of the core perpendicular to a direction of winding axis and an end of the air-core coil in the direction of winding axis is “h”, is provided. The coil device is superior in DC superimposing characteristic while suppressing the magnetic saturation.

Abstract: A coil device including: a core, including a magnetic powder and a resin; an air-core coil; a lead, led from the air-core coil; and a terminal, in which at least the entire air-core coil is buried inside the core, an outer shape of the core is a shape where at least one corner part is removed from an approximate rectangular parallelepiped shape, the removed corner includes an entire side of the approximate rectangular parallelepiped shape in the removed corner, approximately parallel to a direction of a winding axis of the air-coil, and a volume of the removed part is 2% or more of a volume of the approximate rectangular parallelepiped shape, is provided. The coil device can reduce a used amount of the magnetic body while maintaining the magnetic characteristic.

Abstract: A dielectric composition contains major components that are an A-group containing major components that are at least two selected from the group consisting of Ba, Ca, and Sr and a B-group which contains a major component that is selected from Zr and Ti and which contains at least Zr. The dielectric composition contains an amorphous substance containing the A-group and the B-group and a crystalline substance containing the A-group and the B-group. In the dielectric composition, the inequality 0.5???1.5 holds, where ? is the molar ratio of the A-group to the B-group.

Abstract: A dielectric composition containing a crystalline phase represented by a general formula of Bi12SiO20 and a crystalline phase represented by a general formula of Bi2SiO5 as the main components. The dielectric composition contains preferably 5 mass % to 99 mass % of the Bi2SiO5 crystalline phase, and more preferably 30 mass % to 99 mass %.

Abstract: A dielectric film contains as a main component a dielectric composition represented by the general formula (Ba1-xCax)z(Ti1-yZry)O3 wherein 0.001?x?0.400, 0.001?y?0.400, and 0.900?z<0.995. In an X-ray diffraction pattern of the dielectric composition, the dielectric composition has the relation 0.00°?2?c?2?t<0.20° between (001) plane diffraction peak position 2?t of a tetragonal structure represented by the general formula and (100) plane diffraction peak position 2?c of a cubic structure represented by the general formula.

Abstract: A dielectric film contains as a main component a dielectric composition represented by the general formula (Ba1-xCax)z(Ti1-yZry)O3 wherein 0.001?x?0.400, 0.001?y?0.400, and 0.900?z<0.995. In an X-ray diffraction pattern of the dielectric composition, the dielectric composition has the relation 0.00°?2?c?2?t<0.20° between (001) plane diffraction peak position 2?t of a tetragonal structure represented by the general formula and (100) plane diffraction peak position 2?c of a cubic structure represented by the general formula.

Abstract: A dielectric composition contains major components that are an A-group containing major components that are at least two selected from the group consisting of Ba, Ca, and Sr and a B-group which contains a major component that is selected from Zr and Ti and which contains at least Zr. The dielectric composition contains an amorphous substance containing the A-group and the B-group and a crystalline substance containing the A-group and the B-group. In the dielectric composition, the inequality 0.5???1.5 holds, where ? is the molar ratio of the A-group to the B-group.

Abstract: A dielectric composition containing a crystalline phase represented by a general formula of Bi12SiO20 and a crystalline phase represented by a general formula of Bi2SiO5 as the main components. The dielectric composition contains preferably 5 mass % to 99 mass % of the Bi2SiO5 crystalline phase, and more preferably 30 mass % to 99 mass %.

Abstract: An Mn—Zn ferrite wherein 0 to 5000 ppm of a Co oxide in a Co3O4 conversion is contained in a basic component constituted by Fe2O3: 51.5 to 57.0 mol % and ZnO: 0 to 15 mol % (note that 0 is not included) wherein the rest is substantially constituted by MnO; and a value ? in a formula (1) below in said ferrite satisfies ??0.93. ?=((Fe2+?Mn3+?Co3+)×(4.29×A+1.91×B+2.19×C+2.01×D))/((A?B?C?D)×100)??formula (1). Note that in the formula (1), (Fe2+?Mn3+?Co3+): [wt %], A: Fe2O3 [mol %], B: MnO [mol %], C: ZnO [mol %] and D: CoO [mol %]. According to the present invention, a highly reliable Mn—Zn ferrite used as a magnetic core of a power supply transformer, etc. of a switching power supply, etc., having a small core loss in a wide temperature range, furthermore, exhibiting a little deterioration of core loss characteristics under a high temperature (in a high temperature storage test) and having excellent magnetic stability, a transformer magnetic core and a transformer can be provided.

Abstract: A transformer core having a high inductance, small inductance tolerance, and small harmonic distortion, in particular total harmonic distortion (THD), wherein a surface roughness of a gap forming surface (RaG) forming a gap for adjustment of the inductance is not more than 0.70 ?m, preferably not more than 0.45 ?m, a transformer using the same, and a method of production of a transformer core having the above properties polishing the gap forming surface forming the gap by a grinding wheel having polishing abrasives of a particle size of #400 to #8000, preferably #600 to #8000 (JIS-R6001).

Abstract: An Mn—Zn based ferrite composition having a main component comprised of Fe2O3: 51.5 to 54.5 mol %, ZnO: 19.0 to 27.0 mol % and the rest of substantially MnO and a first sub component comprised of 0.002 to 0.040 wt % of SiO2, 0.003 to 0.045 wt % of CaO and 0.010 wt % or less of P with respect to 100 wt % of the main component. In a magnetic core for a transformer comprised of this composition, the THD of the transformer becomes −84 dB or less in a broad frequency band, so it can be preferably used as a magnetic core, for example, for an xDSL modem transformer.

Abstract: A magnetic core composition for an xDSL modem transformer having a main component comprised of MnO: 22.0 to 34.5 mol % and ZnO: 12.0 to 25.0 mol % and the rest of substantially Fe2O3. With a magnetic core for a transformer made of this composition, the THD of the transformer becomes not more than −80 dB in a broad frequency band, so this can be used advantageously as the magnetic core for an xDSL modem transformer.

Abstract: An Mn—Zn ferrite wherein 0 to 5000 ppm of a Co oxide in a CO3O4 conversion is contained in a basic component constituted by Fe2O3: 51.5 to 57.0 mol % and ZnO: 0 to 15 mol % (note that 0 is not included) wherein the rest is substantially constituted by MnO; and a value &agr; in a formula (1) below in said ferrite satisfies &agr;≧0.93.

Abstract: An Mn-Zn based ferrite composition having a main component comprised of Fe2O3: 51.5 to 54.5 mol %, ZnO: 19.0 to 27.0 mol % and the rest of substantially MnO and a first sub component comprised of 0.002 to 0.040 wt % of Sio2, 0.003 to 0.045 wt % of CaO and 0.010 wt % or less of P with respect to 100 wt % of the main component. In a magnetic core for a transformer comprised of this composition, the THD of the transformer becomes −84 dB or less in a broad frequency band, so it can be preferably used as a magnetic core, for example, for an XDSL modem transformer.

Abstract: A magnetic core composition for an xDSL modem transformer having a main component comprised of MnO: 22.0 to 34.5 mol % and ZnO: 12.0 to 25.0 mol % and the rest of substantially Fe2O3. With a magnetic core for a transformer made of this composition, the THD of the transformer becomes not more than −80 dB in a broad frequency band, so this can be used advantageously as the magnetic core for an xDSL modem transformer.