Ube Industries, Inc.

Hitachi, Ltd.

Hitachi Koki Co., Ltd.

Hiroshi Oda

Takuma Sakai

Masao Mitani

Junichi Matsuno

Chikara Hiraoka

Kazuyuki Hamada

Toshikazu Tsumura

Shin-ichi Sakata

Hiroshi Fujino

Shin-Ichi Sakata

Shin-chi Sakata

An Li-containing &#x3b1;-sialon-based phosphor represented by the formula (1): LiEuSiAlON(wherein assuming that average valence of Eu is a, x+ya+&#x3b4;=m; 0.45&#x2266;x&#x3c;1.2, 0.001&#x2266;y&#x2266;0.2, 0.9&#x2266;m&#x2266;2.5, 0.5&#x2266;n&#x2266;2.4, and &#x3b4;&#x3e;0).

Li-containing &#x3b1;-sialon-based phosphor, production process thereof, lighting device and image display device

A practical novel phosphor material composed of an &#x3b1;-type silicon nitride, i.e., an &#x3b1;-type silicon nitride phosphor containing a fluorescence-emittable element throughout an &#x3b1;-type silicon nitride particle from the surface to the inside, is provided. Portions having a high emittable element concentration are preferably present like islands, and the fluorescence-emittable element is preferably a lanthanide metal. A powder composed of a fluorescence-emittable element is added to silicon diimide (Si(NH)) or an amorphous silicon nitride powder obtained by thermally decomposing silicon diimide (Si(NH)), the powders are mixed, and the mixture is fired in a non-oxidizing atmosphere, whereby the phosphor material is obtained.

&#x3b1;-type silicon nitride phosphor and production method thereof

An Li-containing &#x3b1;-sialon phosphor particle by mixing a silicon nitride or nitrogen-containing silicon compound powder, an AlN-containing aluminum source, an Li source and an Eu source, firing the mixture at 1,500 to 1,800&#xb0; C. in a nitrogen-containing inert gas atmosphere under atmospheric pressure to obtain a lithium-containing &#x3b1;-sialon powder working out to a starting material, adding and mixing an additional lithium source to the powder, and re-firing the obtained mixture at a temperature lower than the above firing temperature or at a temperature of 1,100&#xb0; C. to less than 1,600&#xb0; C., at 1,100&#xb0; C. to less than 1,600&#xb0; C., in a nitrogen-containing inert gas atmosphere under atmospheric pressure.

Li-containing &#x3b1;-sialon-based phosphor particle, production method thereof, lighting device, and image display device

A thermistor composition that is in use within a range of room temperature to 400&deg; C. has the general formula Mn,Zn,Ni,Fe,Co,O,, wherein 0.1&lE;a<1, 0&lE;b<1, 0<c<1, 0&lE;d<1 and 0.1<a&plus;b<1. A preferred thermistor composition has a B constant (B,) within a range of 3,300-4,960 K, a resistivity (&rgr;,) within a range of 400-88,000 &OHgr;&middot;cm and a resistance variation rate (&Dgr;R,) of 2% or less. The composition is suitable for a thermistor or a thermistor device using the same.

Thermistor composition

A heat fixing device includes a heating head formed by attaching a radiant plate to the radiant surface of a PTC heating element using an adhesive having an excellent thermal conductivity, and embedding a heating unit, of which surfaces except the radiant surface are shielded with an adiabatic material, in a recess formed in a holder for supporting the heating unit.

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Yamaguchi, Japan

Hiroshi Oda