A magnetically tunable ferrimagnetic filter, including a top casing, a top magnetic conductor, a bottom magnetic conductor, coils, a balance coil, ferrimagnetic-based filters, and a bottom casing. The ferrimagnetic-based filters utilize ferrimagnetic resonator elements, such as yttrium-iron-garnet (YIG), configured to reduce a magnetic gap of the YIG filter and thereby to improve performance.

An inductor component includes an element body including magnetic powder and having first and second principal surfaces; an inductor wiring in the element body; a first vertical wiring that is in the element body, is connected to a first end portion of the inductor wiring, and extends to the first principal surface; a second vertical wiring that is in the element body, is connected to a second end portion of the inductor wiring, and extends to the first principal surface; and first and second external terminals exposed on the first principal surface and connected to the first and second vertical wirings, respectively. The magnetic powder contains an Fe element as a main component, and the first principal surface has an oxidized region, in which an oxide film of oxidized particles of the magnetic powder, is exposed and a non-oxidized region in which particles of the magnetic powder are exposed.

A manganese-zinc ferrite with a high magnetic permeability at negative temperature and low loss at high temperature consists of Fe.sub.2O.sub.3, MnO and ZnO, and additives consisting of CaCO.sub.3, ZrO.sub.2, Co.sub.2O.sub.3 and SnO.sub.2 are also added. A method for preparing the manganese-zinc ferrite is further provided. According to the method, by reasonably adjusting a ratio of Mn to Zn to Fe and appropriately increasing the content of Co in the additives, a manganese-zinc ferrite material with both a high magnetic permeability and low loss at about −20° C. and low loss at 120-140° C. is obtained. The manganese-zinc ferrite material has two loss valleys at about −20° C. and about 100° C. in a temperature range of −30° C. to 140° C., which expands the application range of the manganese-zinc ferrite material.

A multilayer coil component includes an inner conductor, a component element assembly including the inner conductor, and outer conductors disposed at respective end portions of the component element assembly. The component element assembly has a first region in which the primary component is composed of a magnetic material and which may contain a nonmagnetic material and second regions which are disposed at respective end portions of the first region and which contain at least a nonmagnetic material. Each second region is disposed having a greater volume content of the nonmagnetic material than the first region such that, for example, the difference in the volume content results about 25% by volume or more. The coil portion of the inner conductor is embedded in the first region, and the length of the second region is greater than or equal to the length of the side-surface folded portion of the outer conductor.

A core for an electrical apparatus includes a plurality of electrical steel sheets having a ferromagnetic or ferrimagnetic coating applied to both sides of the electrical steel sheets. The electrical steel sheets are arranged in a stack to form a laminated stack. The ferromagnetic or ferrimagnetic coating is applied to both sides of the electrical steel sheets. The coating may comprise MnZn ferrites, NiZn ferrites, MgMnZn ferrites, CoNiZn ferrites, Co ferrites, Ni ferrites, Yttrium iron garnets (Y3Fe5O12) or other ferromagnetic or ferrimagnetic coating materials.

An magnetic component structure with thermal conductive filler is provided in the present invention, including an upper magnetic core, a lower magnetic core combining with the upper magnetic core to form a casing with a front opening and a rear opening, and a coil mounted in the casing, where two terminals of the coil extend outwardly from the front opening, and a thermal conductive filler filling between the casing and the coil in the casing.

A ferrite core includes a ferrite sintered body in which integrally formed are a winding core portion, extending in a lengthwise direction, and flange portions provided at both ends in the lengthwise direction of the winding core portion and projecting from the winding core portion in at least a height direction orthogonal to the lengthwise direction. Pores are present inside the winding core portion and the flange portions, and an abundance ratio of the pores in the winding core portion is equal to or more than about 0.05% and equal to or less than about 1.00% (i.e., from about 0.05% to about 1.00%).

The magnetic tape includes a non-magnetic support, a magnetic layer that includes ferromagnetic powder having an average particle volume of 2,500 nm.sup.3 or less on one surface side of the non-magnetic support, and a back coating layer that includes non-magnetic powder on the other surface side of the non-magnetic support, in which the ferromagnetic powder is ferromagnetic powder selected from the group consisting of hexagonal ferrite powder and ε-iron oxide powder, and a ratio (PSD.sub.5μm-PSDmag/PSD.sub.10μm-PSDbc) of the magnetic layer and the back coating layer is in a range of 0.0050 to 0.20. A magnetic tape cartridge and a magnetic recording and reproducing apparatus include the magnetic tape.

A coil component includes a body having one surface and the other surface opposing each other, and one side surface and the other side surface, respectively connecting the one surface and the other surface to each other and opposing each other in one direction, a wound coil embedded in the body, a lead portion extending from an end of the wound coil to one surface of the body and disposed on the one surface of the body, an insulating layer covering one surface of the body and having an opening exposing a portion of the lead portion and extending in the one direction, and an external electrode disposed in the opening and connected to the lead portion. The insulating layer includes finishing portions respectively disposed on opposing sides of the opening in the one direction.

A sintered material contains Fe in an amount of from 8 mol % to 37 mol % in terms of Fe.sub.2O.sub.3, Zn in an amount of from 30 mol % to 60 mol % in terms of ZnO, Cu in an amount of from 1 mol % to 7 mol % in terms of CuO, Ni in an amount of from 3 mol % to 17 mol % in terms of NiO, and Si in an amount of from 7 mol % to 28 mol % in terms of SiO.sub.2. A mole ratio (SiO.sub.2/Fe.sub.2O.sub.3) of the SiO.sub.2 to the Fe.sub.2O.sub.3 is from 0.2 to 3.5. The sintered material contains B in an amount of from 0.05 mol parts to 0.5 mol parts.