α-Sialon, α-sialon phosphor and method for producing the same

US7906040B2 · kind B2 · utility

Assignees

• NATIONAL INSTITUTE FOR MATERIALS SCIENCE · JP
• DENKI KAGAKU KOGYO KABUSHIKI KAISHA · JP

Inventors

• Mamoru Mitomo · Tsukuba, JP
• Naoto Hirosaki · Tsukuba, JP
• Hideyuki Emoto · Oomuta, JP
• Masahiro Ibukiyama · Tokyo, JP

Key dates

• Filing date: Jun 14, 2005
• Grant date: Mar 15, 2011
• Expiry date: May 4, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/9646
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

An α-sialon is offered which is represented by general formula: (M1)X(M2)Y(Si, Al)12(O, N)16 (wherein M1 represents one or more elements selected from the group which consists of Li, Mg, Ca, Y and lanthanoid (except La and Ce) and M2 represents one or more elements selected from the group which consists of Ce, Pr, Eu, Tb, Yb and Er and wherein 0.3<X+Y<1.5 and 0<Y<0.7), the α-sialon containing from 30 ppm to 1% of fluorine as an impurity. By making primary particles of the α-sialon 1 to 10 μm in average particle size, an α-sialon phosphor can be obtained reproducibly, stably and in a large quantity. Especially, if containing 30 to 200 ppm of impurity fluorine, the α-sialon phosphor can exhibit an excellent emission characteristic as a white fluorescent matter.