A soft magnetic material powder includes soft magnetic material particles, the soft magnetic material particles each include a core formed from an Fe-based soft magnetic material and an insulating film covering the surface of the core, and the insulating film contains an inorganic oxide and a water soluble polymer. A magnetic core includes soft magnetic material particles and a binder bonding the soft magnetic material particles to each other, the soft magnetic material particles each include a core containing an Fe-based soft magnetic material and an insulating film covering the surface of the core, and the insulating film contains an inorganic oxide and a water soluble polymer.

A coil component includes a coil having inner and outer circumferential surfaces, a pair of end surfaces, and a core surrounding at least a part of a periphery of the core. A cross section is where the coil component is cut by a plane, when each of coil sections is divided into eight regions by four straight lines extending along the inner circumferential surface, the outer circumferential surface and the end surfaces. In the cross section, first core members positioned at four corner regions, second core members positioned at an inner side of the inner circumferential surface and an outer side of the outer circumferential surface, and third core members, positioned at outer sides of the end surfaces form the core. At least one of the second and third core members has a magnetic permeability lower than that of the first core member in a zero magnetic field.

A coil component includes a coil having inner and outer circumferential surfaces, a pair of end surfaces, and a core surrounding at least a part of a periphery of the core. A cross section is where the coil component is cut by a plane, when each of coil sections is divided into eight regions by four straight lines extending along the inner circumferential surface, the outer circumferential surface and the end surfaces. In the cross section, first core members positioned at four corner regions, second core members positioned at an inner side of the inner circumferential surface and an outer side of the outer circumferential surface, and third core members, positioned at outer sides of the end surfaces form the core. At least one of the second and third core members has a magnetic permeability lower than that of the first core member in a zero magnetic field.

Provided herein is a magnetic sheet. The magnetic sheet according to one embodiment of the present invention includes a magnetic layer formed of crushed pieces of a magnetic body to improve flexibility of the magnetic sheet, and a thin film coating layer formed on at least one surface of the magnetic layer to maintain the magnetic layer in a sheet shape and buffer an external force applied to the crushed pieces of the magnetic body. According to the present invention, since the magnetic sheet is improved in mechanical strength properties, such as a tensile property, a bending property, and the like, to have significantly superior flexibility, degradation of physical properties, such as magnetic permeability and the like, caused by physical damage such as unintended cracks in the magnetic body provided in the magnetic sheet can be prevented even in the process of storing, transferring, and attaching the magnetic sheet to a target object and during usage of an electronic device provided with the target object to which the magnetic sheet is attached, and the magnetic sheet can be attached to a target surface of the target object with a superior adhering force even when a stepped portion is present at the surface, and at the same time, the magnetic sheet can block the influence of a magnetic field on parts of a portable terminal device or a human body of a user using the portable terminal device, significantly increase transmission and reception efficiencies and distances of a data and/or wireless power signal, and maintain the above-described performance for a long period of time, such that the magnetic sheet can be widely used in various portable devices such as mobile devices, smart appliances, devices for the Internet of Things, and the like.

Provided herein is a magnetic sheet. The magnetic sheet according to one embodiment of the present invention includes a magnetic layer formed of crushed pieces of a magnetic body to improve flexibility of the magnetic sheet, and a thin film coating layer formed on at least one surface of the magnetic layer to maintain the magnetic layer in a sheet shape and buffer an external force applied to the crushed pieces of the magnetic body. According to the present invention, since the magnetic sheet is improved in mechanical strength properties, such as a tensile property, a bending property, and the like, to have significantly superior flexibility, degradation of physical properties, such as magnetic permeability and the like, caused by physical damage such as unintended cracks in the magnetic body provided in the magnetic sheet can be prevented even in the process of storing, transferring, and attaching the magnetic sheet to a target object and during usage of an electronic device provided with the target object to which the magnetic sheet is attached, and the magnetic sheet can be attached to a target surface of the target object with a superior adhering force even when a stepped portion is present at the surface, and at the same time, the magnetic sheet can block the influence of a magnetic field on parts of a portable terminal device or a human body of a user using the portable terminal device, significantly increase transmission and reception efficiencies and distances of a data and/or wireless power signal, and maintain the above-described performance for a long period of time, such that the magnetic sheet can be widely used in various portable devices such as mobile devices, smart appliances, devices for the Internet of Things, and the like.

Provided is a soft magnetic alloy comprising a composition formula (Fe.sub.(1(+))X1.sub.X2.sub.).sub.(1(a+b+c+d+e+f))M.sub.aB.sub.bP.sub.cSi.sub.dC.sub.eZn.sub.f. X1 denotes at least one selected from Co and Ni; X2 denotes at least one selected from Cu, Mg, Al, Mn, Ag, Sn, Bi, O, N, S, and rare earth elements; M denotes at least one selected from Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W; 0.080b0.150, 0c0.060, 0d0.060, 0e0.030, 0.0030f0.080, 0.0030a+f0.080, b+c0.100, 0, 0, and 0+0.50 are satisfied; and the soft magnetic alloy has Fe-based nanocrystals with a bcc structure.

A multilayer coil component includes a multilayer body formed by stacking a plurality of insulating layers on top of one another and that has a coil built thereinto, and a first outer electrode and a second outer electrode that are electrically connected to the coil. The coil is formed by electrically connecting a plurality of coil conductors to one another. A first main surface of the multilayer body is a mounting surface. A stacking direction of the multilayer body and an axial direction of the coil are parallel to the mounting surface. The insulating layers between the coil conductors are composed of a material containing at least one out of a magnetic material and a non-magnetic material. A content percentage of the non-magnetic material in the insulating layers changes in a direction from a first end surface toward a second end surface of the multilayer body.

A multilayer coil component includes a multilayer body formed by stacking a plurality of insulating layers on top of one another and that has a coil built thereinto, and a first outer electrode and a second outer electrode that are electrically connected to the coil. The coil is formed by electrically connecting a plurality of coil conductors to one another. A first main surface of the multilayer body is a mounting surface. A stacking direction of the multilayer body and an axial direction of the coil are parallel to the mounting surface. The insulating layers between the coil conductors are composed of a material containing at least one out of a magnetic material and a non-magnetic material. A content percentage of the non-magnetic material in the insulating layers changes in a direction from a first end surface toward a second end surface of the multilayer body.

A coil component is constituted by a composite magnetic material containing alloy grains whose oxygen atom concentration in their surfaces is 50 percent or less, and resin, and also by a coil. The alloy grains are comprised of first alloy grains and second alloy grains which have different compositions and different average grain sizes. The coil component using the composite magnetic material does not require high pressure when formed.

A coil component is constituted by a composite magnetic material containing alloy grains whose oxygen atom concentration in their surfaces is 50 percent or less, and resin, and also by a coil. The alloy grains are comprised of first alloy grains and second alloy grains which have different compositions and different average grain sizes. The coil component using the composite magnetic material does not require high pressure when formed.