A ferrite composition includes a main component and a sub-component. The main component includes 10.0 to 38.0 mol % of a Fe compound in terms of Fe.sub.2O.sub.3, 3.0 to 11.0 mol % of a Cu compound in terms of CuO, 39.0 to 80.0 mol % (excluding 39.0 mol %) of a Zn compound in terms of ZnO, and a balance of a Ni compound. The sub-component includes 10.0 to 23.0 parts by weight of a Si compound in terms of SiO.sub.2, 0 to 3.0 parts by weight (including 0 parts by weight) of a Co compound in terms of Co.sub.3O.sub.4, and 0.1 to 3.0 parts by weight of a Bi compound in terms of Bi.sub.2O.sub.3 with respect to 100 parts by weight of the main component.

In a three-dimensional printing method example, a build material is applied. A first liquid functional material is applied on at least a portion of the build material. The first liquid functional material includes ferromagnetic nanoparticles that are selected from the group consisting of an iron oxide, a ferrite, a combination of the iron oxide and a ferromagnetic metal oxide, and combinations thereof. The build material is exposed to electromagnetic radiation having a frequency ranging from about 5 kHz to about 300 GHz to sinter the portion of the build material in contact with the first liquid functional material.

A ferrite composition includes a main component and a sub-component. The main component includes 10.0 to 38.0 mol % of a Fe compound in terms of Fe.sub.2O.sub.3, 3.0 to 11.0 mol % of a Cu compound in terms of CuO, 39.0 to 80.0 mol % (excluding 39.0 mol %) of a Zn compound in terms of ZnO, and a balance of a Ni compound. The sub-component includes 10.0 to 23.0 parts by weight of a Si compound in terms of SiO.sub.2, 0 to 3.0 parts by weight (including 0 parts by weight) of a Co compound in terms of Co.sub.3O.sub.4, and 0.1 to 3.0 parts by weight of a Bi compound in terms of Bi.sub.2O.sub.3 with respect to 100 parts by weight of the main component.

The present invention relates to a ferrite sintered plate having a composition comprising 47 to 50 mol % of Fe.sub.2O.sub.3, 7 to 26 mol % of NiO, 13 to 36 mol % of ZnO, 7 to 12 mol % of CuO and 0 to 1.5 mol % of CoO, as calculated in terms of the respective oxides, in which the ferrite sintered plate has a volume resistivity of 110.sup.8 to 110.sup.12.Math.cm and a thickness of 10 to 60 m; and a ferrite sintered sheet comprising the ferrite sintered plate on a surface of which a groove or grooves are formed, and an adhesive layer and/or a protective layer formed on the ferrite sintered plate, in which the ferrite sintered sheet has a magnetic permeability at 500 kHz a real part of which is 120 to 800 and an imaginary part of which is 0 to 30, and a product (m) of the real part of the magnetic permeability at 500 kHz of the ferrite sintered sheet and a thickness of the ferrite sintered plate is 5000 to 48000. The ferrite sintered plate and the ferrite sintered sheet according to the present invention have a high volume resistivity as well as a large value and a small value of a magnetic permeability thereof, and therefore can be suitably used as a shielding plate in a digitizer system.

A method for manufacturing a sintered body, the method including heating a mixture that contains a plurality of particles of a metal oxide having a spinel-type structure, and a metal acetylacetonate under pressure at a temperature of from a melting point or higher of the metal acetylacetonate to 600 C. or lower, to form a sintered body that contains the metal oxide having the spinel-type structure.

A method for manufacturing a sintered body, the method including heating a mixture that contains a plurality of particles of a metal oxide having a spinel-type structure, and a metal acetylacetonate under pressure at a temperature of from a melting point or higher of the metal acetylacetonate to 600 C. or lower, to form a sintered body that contains the metal oxide having the spinel-type structure.

A ferrite sintered magnet includes a composition expressed by a formula (1) of Ca.sub.1-w-xLa.sub.wA.sub.xFe.sub.zCo.sub.mO.sub.19. In the formula (1), w, x, z, and m satisfy a formula (2) of 0.30w0.50, a formula (3) of 0.08x0.20, a formula (4) of 8.55z10.00, and a formula (5) of 0.20m0.40. In the formula (1), A is at least one kind of element selected from a group consisting of Sr and Ba. Cr is further contained at 0.058 mass % to 0.132 mass % in terms of Cr.sub.2O.sub.3.

A composite magnetic material has a plurality of grains having a magnetic ferrite phase, grain boundaries surrounding the grains, and a plurality of nanoparticles disposed at the grain boundaries. The nanoparticles of the composite material are both magnetic and electrically insulating, having a magnetic flux density of greater than about 100 mT and an electrical resistivity of at least about 10.sup.8 Ohm-cm. Also provided is a method of making the composite material. The material is useful for making inductor cores of electronic devices.

In a three-dimensional printing method example, a build material is applied. A first liquid functional material is applied on at least a portion of the build material. The first liquid functional material includes ferromagnetic nanoparticles that are selected from the group consisting of an iron oxide, a ferrite, a combination of the iron oxide and a ferromagnetic metal oxide, and combinations thereof. The build material is exposed to electromagnetic radiation having a frequency ranging from about 5 kHz to about 300 GHz to sinter the portion of the build material in contact with the first liquid functional material.

A frequency-dependent resistance element includes an element assembly composed of a sintered magnetic material and a coil conductor embedded in the element assembly. The sintered magnetic material is composed of a primary component containing Fe, Zn, Ni, and Cu and a secondary component containing Co. In the primary component, on a percent by mole basis, the Fe content is 46.79 to 47.69, the Zn content is 12.60 to 24.84, and the Ni content is 19.21 to 32.36 in terms of Fe.sub.2O.sub.3, ZnO, and NiO, respectively. The molar ratio (Ni:Zn) of Ni to Zn is (1X):X, where X is from about 0.28 to about 0.56. The content of Co in terms of Co.sub.3O.sub.4 is 1.0 to 10.0 parts by mass relative to 100 parts by mass of the primary component containing Fe, Zn, Ni, and Cu in terms of Fe.sub.2O.sub.3, ZnO, NiO, and CuO, respectively.