A radio wave absorber including a magnetic powder and a binder, in which the magnetic powder is a powder of a hexagonal ferrite in which a ratio (σs/β) of a saturation magnetization as to a half-width β of a diffraction peak on a (107) plane is 240 emu.Math.g.sup.−1.Math.degree.sup.−1 or more, where the half-width β is determined by X-ray diffraction analysis.

A method produces a substrate shielded from electromagnetic radiation. The method includes i) providing a first polymer material (a) or a precursor thereof containing at least one conductive filler and at least a second polymer material (b) or precursor thereof; ii) obtaining a substrate by subjecting the first polymer material (a) or the precursor thereof and the second polymer material (b) or the precursor thereof to shaping with material bonding of the first polymer material (a) and the second polymer material (b), and polymerizing, if present, the precursors; and iii) at least partially surrounding an electronic component with the substrate obtained in step ii). A polymer component of the first polymer material (a) includes a thermoplastic elastomer or at least one thermoplastic elastomer, selected from the group consisting of, e.g., thermoplastic polyamide elastomers, thermoplastic copolyester elastomers, thermoplastic olefin-based elastomers, thermoplastic styrene block copolymers, polyether block amides, and mixtures thereof.

Provided is an electromagnetic-wave absorber composition and an electromagnetic-wave absorber that can favorably absorb a plurality of electromagnetic waves of different frequencies in a high frequency band in or above the millimeter-wave band. The electromagnetic-wave absorber composition includes a magnetic iron oxide that magnetically resonates at a high frequency in or above the millimeter-wave band and a resin binder. The electromagnetic-wave absorber composition has two or more extrema separated from each other on a differential curve obtained by differentiating a magnetic property hysteresis loop at an applied magnetic field intensity of from 16 kOe to −16 kOe. The electromagnetic-wave absorber includes an electromagnetic-wave absorbing layer formed of the above-described electromagnetic-wave absorber composition.

A method, system and paint for suppressing emission of high frequency electromagnetic radiation from an electronic system, the electronic system including at least one power supply unit, at least one printed circuit board (PCB) and at least one integrated circuit are provided. The method includes providing an electrically conductive housing configured to accommodate and encase the electronic system, the housing having an inner conductive surface, and applying a layer of an electromagnetic absorbing paint to the inner conductive surface of the housing to substantially cover the inner surface by the layer, the electromagnetic absorbing paint comprises a liquid matrix and an electromagnetic absorbing material.

Wave-absorbing material powder of the present invention has oxidation resistance and salt fog resistance, which includes an iron-containing wave-absorbing material powder, and a metal oxide ceramic layer and a metal phosphate layer sequentially coated on an outside of the iron-containing wave-absorbing material powder from the inside to the outside. A method for preparing the wave-absorbing material powder includes using atomic layer deposition to coat the iron-containing wave absorbing material powder with a metal oxide ceramic coating, and then adopting the atomic layer deposition to coat the metal oxide ceramic coating with a metal phosphate layer; repeating the above steps to form an alternating nano-stack of the metal oxide ceramic coating and the metal phosphate layer outside the iron-containing absorbing material powder; and finally performing a high-temperature annealing treatment. The present invention improves temperature resistance, corrosion resistance and oxidation resistance of wave-absorbing materials.

Provided are: a ferrite powder whereby, when the ferrite powder is applied in a composite material, dropping out of ferrite particles is suppressed without moldability and filling ability being compromised; a ferrite resin composite material; and an electromagnetic shielding material, an electronic material, or an electronic component. This ferrite powder includes at least spherical or polyhedral ferrite particles in which a step structure is provided on surfaces thereof, the step structure having a polyhedral outline in the surfaces of the ferrite particles.

A wireline cable, method, and system for broadband communications and data transfer. The wireline cable comprises insulated conductors, arranged such that circumferentially spaced conductors surround a central conductor. One or more of the conductors is insulated with a magnetic permeable insulation configured to reduce electrical interference with an adjacent conductor.

A composite material and an electromagnetic wave absorber made by molding the same, which are capable of exhibiting an excellent electromagnetic wave absorption function and capable of suppressing the deterioration of mechanical properties of the electromagnetic wave absorber itself. A composite material comprising a single type of thermoplastic resin and a conductive filler contained in a dispersed state in the thermoplastic resin, wherein the composite material includes at least one portion A and a portion B with different conductive filler content percentages in a mixed manner, and wherein the ratio of the conductive filler content percentage in the portion A to the conductive filler content percentage in the portion B is greater than 1.0; and an electromagnetic wave absorber made by molding the same.

A method, a device, and a composition are disclosed. The method includes providing a polyol blend that includes a polyol resin and an electromagnetic (EMA) additive, providing an isocyanate resin selected such that blending the isocyanate resin with the polyol blend results in an EMA spray foam. The device includes a first compartment containing an isocyanate resin and a second compartment containing a polyol blend, which includes a polyol resin and an EMA additive. The composition includes a polyurethane spray foam and an EMA additive blended into the polyurethane spray foam.

A thermally conductive electromagnetically absorbing material includes a plurality of particles dispersed in a binder. The plurality of particles can have a particle size distribution having at least three peaks, where at least a majority of particles within a half width at half maximum of one, but not the other ones, of the at least three peaks are at least partially coated with an electromagnetically absorbing coating. The plurality of particles can include pluralities of first and second particles where a total number of the first particles is at most 1% of a total number of the first and second particles and where the first particles are more electromagnetically absorbing than the second particles. Films, molded articles and systems including the thermally conductive electromagnetically absorbing material are described.