Dowa Electronics Materials Co., Ltd.

Nichia Corporation

Dowa Mining Co., Ltd.

Citizen Electronics Co., Ltd.

Masahiro Gotoh

Kenji Sakane

Akira Nagatomi

Shuji Yamashita

Tetsuya Ikuta

Takayuki Yoshida

Tsukasa Maruyama

Toshihiko Ueyama

Takuyuki Baba

Toru Suzuki

Daisuke Kodama

Hidenori Yamaji

Kazumasa Ikari

Koji Tanaka

A silicon oxide-coated iron powder has a small particle diameter, can achieve high in a high frequency band, and has high insulating property. In a method for producing the powder, a silicon alkoxide is added to a slurry containing iron powder having an average particle diameter of 0.25 μm or more and 0.80 μm or less and an average axial ratio of 1.5 or less dispersed in a mixed solvent of water and an organic material containing water in an amount of 1% by mass or more and 40% by mass or less. Then, a hydrolysis catalyst for the silicon alkoxide is added to perform silicon oxide coating, the method resulting in a silicon oxide-coated iron powder having the high μ' in a high frequency band and the high insulating property.

Silicon oxide-coated iron powder, method for producing the same, molded body for inductor using the same, and inductor

An iron powder and method of making an iron powder. The method includes a step of neutralizing an acidic aqueous solution containing a trivalent iron ion and a phosphorus-containing ion, with an alkali aqueous solution, so as to provide a slurry of a precipitate of a hydrated oxide, or a step of adding a phosphorus-containing ion to a slurry containing a precipitate of a hydrated oxide obtained by neutralizing an acidic aqueous solution containing a trivalent iron ion with an alkali aqueous solution. A silane compound is added to the slurry so as to coat a hydrolysate of the silane compound on the precipitate of the hydrated oxide. The precipitate of the hydrated oxide after coating is recovered through solid-liquid separation, the recovered precipitate is heated to provide iron particles coated with a silicon oxide, and a part or the whole of the silicon oxide coating is dissolved and removed.

Iron powder, silicon oxide coated iron powder,, molded article for inductor, and inductor

A magnetic compound having a small dielectric loss and an antenna constituted by the magnetic compound and an electronic device incorporating the antenna are provided by a metal magnetic powder which is well dispersed in a resin having small dielectric loss, and a magnetic powder composite including: a metal magnetic powder; and one or more elements selected from carboxylic acid or its anhydride, aromatic carboxylic acid ester, and a derivative thereof, having a property that real part &#x3bc;' permeability is 1.45 or more, tan &#x3b4;&#x3bc; is 0.1 or less, tan &#x3b4;&#x3b5; is 0.05 or less at a measuring frequency of 2 GHz, when a magnetic powder composite is prepared by adding 5 parts by mass of one or more elements selected from the carboxylic acid or its anhydride, the aromatic carboxylic acid ester, and the derivative thereof to 100 parts by mass of the metal magnetic powder.

Magnetic powder composite, antenna and electronic device, and method for producing the same

A method for producing a Fe&#x2014;Co alloy powder suitable for an antenna includes steps, wherein when introducing an oxidizing agent into an aqueous solution containing Fe ions and Co ions to generate crystal nuclei and cause precipitation and growth of a precursor having Fe and Co as components, Co in an amount corresponding to 40% or more of the total amount of Co used for the precipitation reaction is added to the aqueous solution at a time after the start of the crystal nuclei generation and before the end of the precipitation reaction to obtain the precursor. Then, a dried product of the precursor is reduced to obtain a Fe&#x2014;Co alloy powder. This Fe&#x2014;Co alloy powder has a mean particle size of 100 nm or less, a coercive force Hc of 52.0 to 78.0 kA/m, and a saturation magnetization ss of 160 Am/kg or higher.

Fe&#x2014;Co alloy powder and method for producing the same, and antenna, inductor and EMI filter

An object is to provide a magnetic compound excellent in high frequency properties and excellent in mechanical strength, and its related items, using the polyarylene sulfide resin, and to provide a technique regarding the magnetic compound having a metal magnetic powder and a polyarylene sulfide resin, and satisfying both mechanical strength and high frequency properties.

Magnetic compound and antenna

To reduce impurity contents of carbon and oxygen not contributing to light emission, then suppress deterioration of emission intensity of a phosphor, and improve emission efficiency of this phosphor. Therefore, there is provided a firing method of nitride or oxynitride phosphors, wherein a cruciblemade of nitride is used as a firing container, and firing is performed, with this crucible covered with a lid (container), to manufacture the phosphor. The phosphor is expressed by a general composition formula MABON:Z in which element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is an activating agent, satisfying o&#x2267;0.

Manufacturing method of nitride phosphor or oxynitride phosphor

A phosphor, which has less reduction in emission efficiency and is capable of keeping high luminance even when density of an electron beam for exciting the phosphor increases, is provided. As raw materials, CaN(2N), AlN (3N), SiN(3N), and EuO(3N) are prepared, and each of the raw materials is weighed so that a mole ratio of each element is, for example, (Ca+Eu):Al:Si=1:1:1, and mixed, then the mixture is held and fired at 1500&#xb0; C. under the inert atmosphere for three hours, and thereafter ground to produce a phosphor having a composition formula of CaSiAlN:Eu.

Phosphor for electron beam excitation and color display device using the same

A phosphor including a main production phase of a phosphor expressed by a composition formula of MmAaBbOoNn:Zz (where an element M is one or more bivalent elements, an element A is one or more trivalent elements, an element B is one or more tetravalent elements, O is oxygen, N is nitrogen, an element Z is an activator, n=2/3m+a+4/3b&#x2212;2/3o, m/(a+b)&#x2267;1/2, (o+n)/(a+b)&#x3e;4/3, wherein m=a=b=1 and o and n is not 0). A phosphor including 24 wt % to 30 wt % of Ca (calcium), 17 wt % to 21 wt % of Al (aluminum), 18 wt % to 22 wt % of Si (silicon), 1 wt % to 15 wt % of oxygen, 15 wt % to 33 wt % of nitrogen and 0.01 wt % to 10 wt % of Eu (europium), wherein an emission maximum in an emission spectrum is in a range of 600 nm to 660 nm; and wherein color chromaticity x of light emission is in a range of 0.5 to 0.7, and color chromaticity y of the light emission is in a range of 0.3 to 0.5.

Phosphor and production method of the same, method of shifting emission wavelength of phosphor, and light source and LED

A light emitting device 10 includes: a lead frame 12serving as a mounting portion having a cup 13; a light emitting element 14, mounted on the bottom face 13of the cup, for emitting light having a predetermined peak wavelength; a layer of large phosphor particles 16, adsorbed and formed on the light emitting element, for absorbing light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the light emitted from the light emitting element; small phosphor particles 18, which have a smaller particle diameter than that of the large phosphor particles, for absorbing at least one of light emitted from the large phosphor particles and light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the at least one of the light emitted from the large phosphor particles and the light emitted from the light emitting element; and a sealing member 20, in which the small phosphor particles are dispersed, for sealing the light emitting element and the layer of large phosphor particles in the cup.

Light emitting device and method for producing same

A phosphor having an excitation band relative to lights in the wide range of wavelengths from ultraviolet to visible light, and having an emission spectrum in the red range and so on, with a wide half value width, and an LED and a light source using the phosphor and emitting white and other color lights with good color rendering properties are provided. Powdered raw materials of CaN(2N), CaO (2N), AlN (3N), SiN(3N), and EuO(3N) are prepared, and the respective raw materials are mixed to have a mole ratio of the respective elements of Ca:Al:Si:Eu=0.985:1:1:0.015. The mixed raw materials are fired at 1000&#xb0; C. or higher in an inert atmosphere for three hours, and thereafter pulverized to obtain a phosphor having a composition of CaAlSiNO:Eu, which is one example of the phosphor satisfying the above described object. Furthermore, by combining the phosphor with an appropriate LED or a light source emitting from ultraviolet light to visible light, the LED and the light source emitting white and other color lights with good color rendering properties can be obtained.

Light source having phosphor including divalent, trivalent and tetravalent elements

To provide a phosphor for an electron beam excitation with a small deterioration in an emission efficiency and capable of maintaining a high luminance, even when an excitation density of an electron beam for a phosphor excitation is increased. As raw materials, CaN(2N), AlN(3N), SiN(3N), and EuO(3N) are prepared, and the raw materials thus prepared are measured and mixed, so that a molar ratio of each element becomes (Ca+Eu):Al:Si=1:1:1. Then, the mixture thus obtained is maintained and fired for at 1500&#xb0; C. for 3 hours, and thereafter crushed, to manufacture the phosphor having a composition formula CaSiAlN:Eu.

Phosphor and phosphor film for electron beam excitation and color display apparatus using the same

To provide a phosphor given by a general composition formula expressed by MmAaBbOoNn:Z, (wherein element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kind of activating agent, satisfying m&#x3e;0, a&#x3e;0, b&#x3e;0, o&#x2267;0, and n&#x3e;0), with a change rate of a ratio of element B atoms to the total numbers of atoms being smaller by 10% or the change rate of oxygen atoms to the total numbers of atoms being smaller by 40% in a range from a particle surface up to depth 2000 nm, having a broad emission spectrum in a range of blue color, having a broad flat excitation band in a range of near ultraviolet/ultraviolet, and having excellent emission efficiency, emission intensity, and luminance.

Phosphor, manufacturing method of phosphor sheet and phosphor, and light emitting device using the phosphor

To provide a phosphor having an emission characteristic such that a peak wavelength of light emission is in a range from 580 to 680 nm, and having a high emission intensity, and having a flat excitation band with high efficiency for excitation light in a broad wavelength range from ultraviolet to visible light (wavelength range from 250 nm to 550 nm). For example, CaN(2N), AlN(3N), SiN(3N), EuO(3N) are prepared, and after weighing and mixing a predetermined amount of each raw material, raw materials are fired at 1500&#xb0; C. for 6 hours, thus obtaining the phosphor including a product phase expressed by a composition formula CaAlSiN:Eu and having an X-ray diffraction pattern satisfying a predetermined pattern.

Phosphor and manufacturing method for the same, and light source

A light emitting deviceincludes: a lead frameserving as a mounting portion having a cup; a light emitting element, mounted on the bottom faceof the cup, for emitting light having a predetermined peak wavelength; a layer of first phosphor particles, absorbed and formed on the light emitting element, for absorbing light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the light emitted from the light emitting element; second phosphor particlesfor absorbing at least one of light emitted from the first phosphor particles and light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the at least one of the light emitted from the first phosphor particles and the light emitted from the light emitting element; and a sealing member, in which the second phosphor particles are dispersed, for sealing the light emitting element and the layer of first phosphor particles in the cup.

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Tokyo, Japan

Masahiro Gotoh