Tdk Corporation

Munemitsu Hamada

Hitoshi Masumura

Haruo Taguchi

Akira Takeishi

Shouichi Iwaya

Makoto Takahashi

Dai Matsuoka

Shoichi Iwaya

Masatada Yodogawa

Hiraku Harada

Takeshi Masuda

Minoru Takaya

Hisashi Kobuke

Hisanao Tosaka

Tomohiro Sogabe

Masaru Fukuda

Hiroyuki Satoh

Shigeru Moriya

Shigeya Takahashi

Yasutoshi Yamaguchi

Hiroaki Abe

An electron-emitting electrode for discharge lamps etc. uses an electron-emitting material which contains a first metal component selected from Ba, Sr and Ca and a second metal component selected from Ta, Zr, Nb, Ti and Hf and also contains oxynitride perovskite. The electron-emitting material has restrained evaporation during electric discharge and a high resistance to ion sputtering.

Electrode

An electron-emitting material contains a first metal component selected from Ba, Sr and Ca and a second metal component selected from Ta, Zr, Nb, Ti and Hf and also contains oxynitride perovskite. The electron-emitting material has improved electron emission characteristics, restrained evaporation at elevated temperatures, and minimized consumption by ion sputtering. The electron-emitting material is prepared by firing a metal component-containing raw material disposed in proximity to carbon in a nitrogen gas-containing atmosphere to thereby create oxynitride perovskite.

Electron-emitting material and preparing process

The present invention provides an electrode for a ceramic electrode fluorescent discharge lamp; an electrode material for a discharge lamp, which has high electron flow density, high thermal shock resistance, and reduced deterioration due to sputtering; and also a method for manufacturing the same. The invention makes it possible to reduce the tube diameter of the ceramic electrode fluorescent discharge lamp. An electrode material for a discharge lamp is obtained from a first component of 0.5 to 1.5 mols of BaO, CaO or SrO, a second component of 0.05 to less than 0.3 mols or more than 0.7 to 0.95 mols of ZrO,or TiO,, and a third component of 0.025 to less than 0.3 mols of V,O,, Nb,O,, Ta,O,, Sc,O,, Y,O,, La,O,, Dy,O,, or Ho,O,, or 0.05 to less than 0.15 mols or more than 0.35 to 0.95 mols of HfO,, CrO,, MoO,or WO,. This electrode material is granulated and is turned into a massive, granular, or porous electrode material. This is placed in a cylindrical semiconductor ceramic container with a closed bottom and is reduced and fired to prepare an electrode. A mercury dispenser of the ceramic electrode fluorescent discharge lamp is disposed in series between the cylindrical semiconductor ceramic container with a closed bottom and a lead-in portion of the lead wire.

Discharge lamp electrode

Ceramic cathode fluorescent discharge lamp

An organic PTC thermistor having a positive temperature coefficient of resistivity, which comprises a PTC composition comprising an organic polymer having dispersed therein a conductive substance, and at least one pair of electrodes, wherein the conductive substance is tungsten carbide powder; or the electrodes each comprise a metal mesh and a metal layer.

Organic PTC thermistor

A ceramic piezoelectric, includes a thick core formed of a sintered ceramic material, and a pair of electrodes formed on opposing end faces of the core, wherein the electrodes are a reduced form of the ceramic material of the core. The electrodes may also be a reduced layer of an oxide formed on the ceramic material of the core.

Ceramic piezoelectric element with electrodes formed by reduction

A semiconductive ceramic composition capable of permitting its resistance-temperature characteristics and resistance to be controlled as desired and a firing temperature of the composition to be lowered to a degree sufficient to facilitate the mass-production at a low cost. The composition contains a main component consisting of SrO, PbO and TiO.sub.2 and is subjected to firing in an oxidizing atmosphere. The composition may contain at least one of SiO.sub.2 and M as a minor component. A variation in amount of the main and minor components permits characteristics and properties of the composition to be varied as desired.

Semiconductive ceramic composition

A ceramic capacitor, includes a thick core formed of a sintered ceramic material, and a pair of electrodes formed on opposing end faces of the core, wherein the electrodes are a reduced form of the ceramic material of the core. The electrodes may also be a reduced layer of an oxide formed on the ceramic material of the core.

Ceramic capacitor with electrodes formed by reduction

A discharge lamp device includes a tube, and a cathode disposed in said tube and made of a valence-compensated semiconductor ceramic material, or a forcibly reduced semiconductor ceramic material, or a valence-compensated and forcibly reduced semiconductor ceramic material. Since the cathode does not include an electron-emitting material, but uses a semiconductor ceramic material, no vapor is produced by the cathode and also the cathode does not react with mercury vapor filled in the tube. Therefore, the discharge lamp device has improved characteristics such as greater heat resistance, better chemical resistance, and improved discharge characteristics. The discharge lamp device is less costly because the semiconductor ceramic material used as the cathode is inexpensive.

Growing community of inventors

Tokyo, Japan

Munemitsu Hamada