Denki Kagaku Kogyo Kabushiki Kaisha

Mitsuru Kawagoe

Tomohiro Nomiyama

Takashi Kawasaki

Hideyuki Emoto

Suzuya Yamada

Ryozo Nonogaki

Provided are an &#x3b1;-SiAlON activated by Eu, which can realize a higher luminance in a light-emitting device such as a white LED, and also a light-emitting device. The &#x3b1;-SiAlON is represented by the general formula: (M)(Eu)(Si)(Al)(O)(N)(wherein M denotes one or more elements including at least Ca, selected from the group consisting of Li, Mg, Ca, Y and lanthanide elements (except for La and Ce)), and is constituted by an &#x3b1;-SiAlON having Eu in the form of a solid solution. The 50% mean area diameter of primary particles of the &#x3b1;-SiAlON is 5 &#x3bc;m or more, and the ratio of the 50% mean area diameter of primary particles to the 50% mean area diameter of secondary particles of the &#x3b1;-SiAlON is preferably 0.56 or more. A light-emitting deviceincludes a light-emitting light sourceand a wavelength conversion member, wherein the wavelength conversion memberincludes a &#x3b1;-SiAlONfor absorbing near-ultraviolet to blue light generated by the light-emitting light sourceto generate yellow to orange light.

&#x3b1;-SiAlON, light-emitting device and use thereof

&#x3b1;-sialon phosphor that is &#x3b1;-sialon represented by a general expression: (M)(Eu)(Si, Al)(O, N)(where M is one or more types of elements selected from a group consisting of Li, Mg, Ca, and Y as well as lanthanide element (except for La and Ce) and including at least Ca), the &#x3b1;-sialon phosphor being structured so that an oxygen content is 1.2 mass % or less and primary particles constituting the &#x3b1;-sialon have a columnar shape. When the &#x3b1;-sialon phosphor receives ultraviolet rays or visible light having a wavelength from 250 to 500 nm as an excitation source, the &#x3b1;-sialon phosphor shows a fluorescent characteristic having a peak in a wavelength region from 595 to 630 nm.

&#x3b1;-sialon phosphor, method for producing same, and light-emitting device

A fluorescent material comprising: a &#x3b2;-Sialon expressed by the general formula SiAlONas a host material; and Eu dissolved in solid solution as a luminescence center, is a powder which, when measured by the laser diffraction scattering method, gives particle diameter distribution in which cumulative 10% diameter (D) falls within the 7 &#x3bc;m to 20 &#x3bc;m range and 90% diameter (D) within the 50 &#x3bc;m to 90 &#x3bc;m range, and can be used as a fluorescent material low in luminescence intensity degradation ideal for illuminators. This fluorescent material can be produced by subjecting a raw powder, which is obtained by mixing a silicon nitride powder, aluminum nitride powder, and aluminum-containing or Eu-containing compound as required, to heating at 1850&#xb0; C. to 2050&#xb0; C. for 9 hours or longer in a nitrogen or nonoxidizing atmosphere.

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Machida, Japan

Mitsuru Kawagoe