A forming method of a composite magnetic sheet. The forming method comprises a preparing step, a forming step and a heat-treating step. In the preparing step, magnetic slurry is prepared by mixing at least a soft magnetic powder having a flat shape, a first resin having a solid component and a second resin having a solid component, weight loss of the solid component of the first resin being 4.0% or less at 220° C., weight loss of the solid component of the second resin being 5.0% or more at 220° C. In the forming step, the magnetic slurry is formed into an intermediate body having a sheet-like shape. In the heat-treating step, the intermediate body is heat-treated at a heat-treatment temperature between 220° C. and 400° C. (both inclusive).

A dust core contains magnetic nanoparticles whose average particle size is 1 to 300 nm, and an aromatic compound that includes two or more functional groups of at least one type selected from a group consisting of a carboxy group and a hydroxy group.

A reactor including: a coil having a winding portion; a magnetic core that is disposed extending inside and outside the winding portion, and is configured to form a closed magnetic circuit; and a resin mold that includes an inner resin disposed between the winding portion and the magnetic core, and does not cover an outer peripheral face of the winding portion.

Provided are a resin composition, which is used for transfer molding, including a resin (A), a magnetic powder (B) having a median diameter of 7.5 to 100 μm, and particles (C) having a median diameter of 0.2 to 5 μm, in which a saturation magnetic flux density of a molded article obtained by transfer molding the resin composition at 175° C. is equal to or more than 1.1 T; and a molded article formed of the resin composition. The particles (C) may include a magnetic powder or a non-magnetic powder.

Provided are a resin composition, which is used for transfer molding, including a resin (A), a magnetic powder (B) having a median diameter of 7.5 to 100 μm, and particles (C) having a median diameter of 0.2 to 5 μm, in which a saturation magnetic flux density of a molded article obtained by transfer molding the resin composition at 175° C. is equal to or more than 1.1 T; and a molded article formed of the resin composition. The particles (C) may include a magnetic powder or a non-magnetic powder.

A magnetic particle-containing composition contains magnetic particles having a plurality of peak tops in a particle size distribution curve showing a volume-based frequency distribution, a resin, and a solvent.

A magnetic particle-containing composition contains magnetic particles having a plurality of peak tops in a particle size distribution curve showing a volume-based frequency distribution, a resin, and a solvent.

The invention provides a method for manufacturing a powder magnetic core through simple compression molding and capable of manufacturing a complicatedly shaped powder magnetic core with reliable high strength and insulating properties. The invention is directed to a method for manufacturing a powder magnetic core with a metallic soft magnetic material powder, the method including: a first step including mixing a soft magnetic material powder and a binder; a second step including compression molding the mixture obtained after the first step; a third step including performing at least one of grinding and cutting on the compact obtained after the second step; and a fourth step including heat-treating the compact after the third step, wherein in the fourth step, the compact is heat-treated so that an oxide layer containing an element constituting the soft magnetic material powder is formed on the surface of the soft magnetic material powder.

The invention provides a method for manufacturing a powder magnetic core through simple compression molding and capable of manufacturing a complicatedly shaped powder magnetic core with reliable high strength and insulating properties. The invention is directed to a method for manufacturing a powder magnetic core with a metallic soft magnetic material powder, the method including: a first step including mixing a soft magnetic material powder and a binder; a second step including compression molding the mixture obtained after the first step; a third step including performing at least one of grinding and cutting on the compact obtained after the second step; and a fourth step including heat-treating the compact after the third step, wherein in the fourth step, the compact is heat-treated so that an oxide layer containing an element constituting the soft magnetic material powder is formed on the surface of the soft magnetic material powder.

A magnetic base body according to one embodiment of the invention includes soft magnetic metal particles that have an insulating film on their surfaces. In a Raman spectrum obtained by observing light scattered when the magnetic base body is irradiated with an excitation laser with a wavelength of 488 nm, a peak intensity ratio. that is defined as a ratio of the peak intensity of a first peak existing at around a wave number of 712 cm.sup.−1 to the peak intensity of a peak existing at around a wave number of 1320 cm.sup.−1, is 1 to 70.