Toto Ltd.

Masami Ando

Takayuki Ide

Makoto Hayakawa

Koichi Hayashi

Mitsuyoshi Machida

Tomoyasu Ichiki

Hirotaka Ishibashi

Masaaki Ito

Masakatsu Kiyohara

Atsushi Kitamura

Toshihiro Aoshima

Katsuhiro Kawakami

Satoshi Horiuchi

Osamu Okamoto

Jun Miyaji

Takero Tokizono

Hiromi Arimitsu

Disclosed is a process for producing a RBSiC member that has a large size and a complicated shape and possesses ceramic properties. The process is Selective Laser Sintering process which includes providing a raw material containing silicon carbide particles and a binder, forming a thin layer of the raw material, and sintering the thin layer by irradiating a desired area in the thin layer with laser to form a sintered thin layer, repeating the step of forming the sintered thin layer to obtain a green body, impregnating the green body with a carbon source and curing the green body impregnated with the carbon source to give a cured body, carbonizing an organic compound component in the cured body to give a fired body, and infiltrating the fired body with silicon and subjecting the fired body to reaction sintering to give a RBSiC member, wherein the fired body contains 8% to 30% by weight of carbon.

Process for producing reaction bonded silicon carbide member

This producing method includes: a preparing step of preparing a pair of ceramic sintered bodies at least one of which is formed by a reaction sintering method and contains free silicon; a forming step of interposing a joining slurry between the joined surfaces of the pair of ceramic sintered bodies and thereafter drying the joining slurry, to form a fine particle layer, the joining slurry obtained by dispersing fine particles containing a carbon element in an organic solvent; and a joining step of heating the pair of ceramic sintered bodies in an inert atmosphere with the pair of ceramic sintered bodies held so that the fine particle layer is pressurized, to introduce the free silicon into the fine particle layer, thereby forming a joining layer containing at least silicon carbide so that the pair of ceramic sintered bodies are joined to each other, to obtain the ceramic joined body.

Method for producing ceramic joined body

A corrosion-resistant member includes a ceramic member containing yttrium oxide as a main component, containing cerium element, and obtained by firing under a nonoxidizing atmosphere. The corrosion-resistant member that has high corrosion-resistant characteristics and includes a ceramic member having a low volume resistivity can be provided.

Corrosion-resistant member and method of manufacturing same

The present invention provides an electrostatic chuck in which the surface can be kept smooth after being exposed to plasma, so as to protect a material to be clamped such as a silicon wafer from being contaminated with particles, and which is excellent in clamping and releasing a material to be clamped and easy to manufacture by low-temperature firing. The electrostatic chuck includes a dielectric material in which alumina is 99.4 wt % or more, and titanium oxide is more than 0.2 wt % and equal to or less than 0.6 wt %, wherein the electrostatic chuck's volume resistivity is 10-10&#x3a9;cm in room temperature, and wherein the titanium oxide segregates in boundaries of particles of the alumina.

Electrostatic chuck

A ceramic member having a high density, small grain diameter, and excellent plasma resistance is provided. The ceramic member is constituted of a fine structure composed of fine grains, which is a ceramic member comprising an yttria as a main component and obtained through firing, wherein the ceramic member has an open porosity, as determined through a measurement by the Archimedes method, of less than 0.5%. By diminishing open voids, sites which is an origin of plasma erosion can be diminished. Thus, a ceramic member having excellent plasma resistance can be provided. By inhibiting abnormal grain growth to form a ceramic member constituted of stall grains, particle contamination by dusting can be reduced. Thus, plasma resistance and preventing particulate contamination can be improved.

Ceramic member and corrosion-resisting member

A rare-earth oxide sintered body, or corrosion-resistant material, having low sintering temperature and high density is prepared by adding a boron compound at a ratio of 0.06 mol % or more and less than 25 mol % when converted into boron oxide (BO) to oxide powder of at least one of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and Sc, after which the mixed powder is formed and sintered. The sintered body comprises at least one of LaO, NdO, SmO, EuO, GdO, DyO, HoO, ErO, TmO, YbO, LuO, and ScO, and at least one of LnBO(Ln=La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu), and ScBOas a main constituent crystal thereof.

Rare-earth oxide sintered body and manufacturing method

The object of the present invention is to provide a rare-earth oxide sintered body having low sintering temperature and high density. A boron compound is added at a ratio of 0.06 mol % or more and less than 25 mol % when converted into boron oxide (BO) to oxide powder of at least one of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and Sc, the mixed powder is formed and sintered.

Rare-earth sintered body and manufacturing method

A sanitary ware comprises a sanitary ware body and a surface glaze layer provided on the sanitary ware body. The surface glaze layer has a center line average roughness Ra of less than 0.07 &mgr;m as measured with a stylus type surface roughness tester according to JIS B 0651-1996.

Sanitary ware and process for producing the same

Sanitary wares having a controlled surface are disclosed which are less likely to be stained or soiled and/or possess excellent gloss. The first sanitary ware comprises a sanitary ware body and a surface glaze layer provided on the sanitary ware body, wherein the surface glaze layer has a center line average roughness Ra of less than 0.07 &mgr;m. This sanitary ware is advantageous in that stains or soils are much less likely to be adhered to the surface thereof and, even when adhered to the surface thereof, can be removed by a weak water stream. The second sanitary ware comprises a sanitary ware body and a surface glaze layer provided on the sanitary ware body, wherein the surface glaze layer has a kurtosis Rku of less than 2.70. This sanitary ware advantageously possesses excellent surface gloss. The third sanitary ware comprises a sanitary ware body and a surface glaze layer provided on the sanitary ware body, wherein the surface of the surface glaze layer consists essentially of a vitreous component and is free from silica particles having a particle diameter of not less than 10 &mgr;m. This sanitary ware is advantageous in that stains or soils are less likely to be adhered to the surface thereof.

Disclosed is a sanitary ware which has a self-cleaning function for releasing carboxyl-containing greasy stains or soils, such as fatty acids, fatty esters, metallic soaps (scum of soaps), proteins, amino acids, bacteria, and fungi, and deposited stains or soils, such as water scale and urinary calculi. This sanitary ware comprises at least a sanitary ware body and a glaze layer as an outermost layer of the sanitary ware, a monovalent metal component and/or a metal component having a measure of the electronegativity based on Pouling's rule of not more than 1 being provided so as to be releasable evenly and continuously, over the whole surface of the glaze layer as the outermost layer, in such an amount large enough to impart a self-cleaning function for releasing stains or soils to the surface of the glaze layer as the outermost layer, the metal component being suppliable from the glaze layer as the outermost layer and/or the sanitary ware body to the whole surface of the outermost layer. The sanitary ware is advantageous in that stains or soils on the sanitary ware can be simply removed, for example, by running water without using any surfactant and without strongly scrubbing the surface of the sanitary ware by a scrubbing brush or a cleaning brush.

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Fukuoka, Japan

Masami Ando