Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Toshiba Lighting & Technology Corporation

Kenji Terashima

Masaaki Tamatani

Yoshio Kimura

Masao Asada

Satoshi Sugano

Masahiko Yamakawa

Shigeru Ando

Kazuaki Nakagawa

Akira Taya

Yoji Yuge

Hidenori Ito

Fumiyasu Yanagisawa

Shoji Naoki

Akio Watanabe

A luminescent material for a mercury discharge lamp comprises a phosphor material including phosphor particles for emitting a luminous flux upon excitation by ultraviolet radiation at 254 nm and a protective layer continuously formed on the phosphor particle with at least one metal oxide selected from the group consisting of MgO, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Sm.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Dy.sub.2 O.sub.3, Ho.sub.2 O.sub.3, Er.sub.2 O.sub.3, Yb.sub.2 O.sub.3, Lu.sub.2 O.sub.3, CaO, ZrO.sub.2, SrO, BaO, .alpha.-Al.sub.2 O.sub.3 and BeO. A mercury discharge lamp has a luminescent layer coated with the luminescent material on the wall of the light transmissive bulb thereof.

Luminescent material for mercury discharge lamp including phosphor and a

A fluorescent lamp characterized in that the charging tendency of a phosphor used is positioned more negative side than that of metal oxides each having a metal ion electronegativity X.sub.i of 7.0 but more positive side than that of metal oxides each having a metal ion electronegativity X.sub.i of 11.8, that particles of the phosphor are charged positive and smaller than 3.0 .mu.C per gram when they are in contact with soda lime glass beads each having a particle size of 200-500 .mu.m, or that they are charged negative and larger than -0.5 .mu.C per gram when they are in contact with reduced iron powder having a particle size of 44-74 .mu.m.

Fluorescent lamp with phosphor having coated phosphor particles

According to the present invention, there is provided a phosphor represented by a general formula (Ba.sub.w Ca.sub.x Mg.sub.y Eu.sub.z)O.aAl.sub.2 O.sub.3. bSiO.sub.2 where 0.1.ltoreq.w.ltoreq.0.5, 0.0004.ltoreq.x.ltoreq.0.0020, 0.1.ltoreq.y.ltoreq.0.8, 0.03.ltoreq.z.ltoreq.0.10, w+x+y+z=1, 1.5.ltoreq.a.ltoreq.4.5, and 0.0005.ltoreq.b.ltoreq.0.0030. The present invention provides a blue-color light-emitting aluminate phosphor which has a high emission output and a low decrease in its emission intensity during use, and a fluorescent lamp using the same.

Phosphor and fluorescent lamp using the same

Green-emitting phosphor

Fluorescent lamp

Growing community of inventors

Chigasaki, Japan

Kenji Terashima