Abstract: A titanium oxide powder holding a barium compound on the surface of the particles thereof is used for manufacturing a highly crystalline fine barium titanate powder by solid-phase reaction. When the titanium oxide powder and a barium-containing powder material are mixed and calcined to prepare the barium titanate powder, the barium compound on the surfaces of the titanium oxide powder particles inhibits the sintering, or the growth, of the titanium oxide during the calcination. Consequently, the resulting barium titanate powder is highly crystalline and fine.

Abstract: A titanium oxide powder holding a barium compound on the surface of the particles thereof is used for manufacturing a highly crystalline fine barium titanate powder by solid-phase reaction. When the titanium oxide powder and a barium-containing powder material are mixed and calcined to prepare the barium titanate powder, the barium compound on the surfaces of the titanium oxide powder particles inhibits the sintering, or the growth, of the titanium oxide during the calcination. Consequently, the resulting barium titanate powder is highly crystalline and fine.

Abstract: A titanium oxide powder holding a barium compound on the surface of the particles thereof is used for manufacturing a highly crystalline fine barium titanate powder by solid-phase reaction. When the titanium oxide powder and a barium-containing powder material are mixed and calcined to prepare the barium titanate powder, the barium compound on the surfaces of the titanium oxide powder particles inhibits the sintering, or the growth, of the titanium oxide during the calcination. Consequently, the resulting barium titanate powder is highly crystalline and fine.

Abstract: A solid-phase method for making a barium titanate powder involves the steps of compounding powdered barium carbonate and powdered titanium oxide and calcining the mixture. The powdered barium carbonate used is needle particles having an aspect ratio of the length of the long axis to the length of the short axis of at least about 2. The powdered barium carbonate preferably has a specific surface area of about 5 m2/g or more. The resulting barium titanate powder is finer and homogeneous.

Abstract: A method for making a dielectric ceramic material powder containing a basic component powder including particles of a basic component for making a dielectric ceramic, a first additive component and a second additive component is provided. The first additive component has an effect of preventing the second additive component from forming a solid solution with the basic component powder. The method includes the steps of diffusing the first additive component into a surface region of each particle of the basic component powder, and adding the second additive component to the resulting basic component powder. After the dielectric ceramic material is sintered, each of the particles of the sintered compact can reliably have a core-shell structure that includes a core containing no second additive component and a shell containing diffused second additive component.

Abstract: A barium carbonate powder having a specific surface area of at least about 20 m2/g is mixed with a titanium oxide powder to form a powder mixture. The titanium oxide powder has such a specific surface area that the specific surface area ratio of the titanium oxide powder to the barium carbonate powder is at least about 1. The powder mixture is calcined and thus results in a fine barium titanate powder having a high content of tetragonal crystals and a small range of compositional variation.

Abstract: A solid-phase method for making a barium titanate powder involves the steps of compounding powdered barium carbonate and powdered titanium oxide and calcining the mixture. The powdered barium carbonate used is needle particles having an aspect ratio of the length of the long axis to the length of the short axis of at least about 2. The powdered barium carbonate preferably has a specific surface area of about 5 m2/g or more. The resulting barium titanate powder is finer and homogeneous.

Abstract: A titanium oxide powder holding a barium compound on the surface of the particles thereof is used for manufacturing a highly crystalline fine barium titanate powder by solid-phase reaction. When the titanium oxide powder and a barium-containing powder material are mixed and calcined to prepare the barium titanate powder, the barium compound on the surfaces of the titanium oxide powder particles inhibits the sintering, or the growth, of the titanium oxide during the calcination. Consequently, the resulting barium titanate powder is highly crystalline and fine.

Abstract: A method for manufacturing a powdered raw material of a basic powdered dielectric ceramic composition having compounds containing metal elements thereon. The method comprises the steps of dispersing a basic powdered dielectric ceramic composition in water to form a slurry, adding a silicon compound to the slurry to coat the powder, adding a solution containing the metal elements and a precipitating agent reactive therewith to form a precipitate, while the slurry is being stirred, and rinsing and drying the slurry.

Abstract: A fine powder heat treating apparatus which includes a container rotated by an electric motor, a quantity of rolling media disposed in the container and a heater provided for heating the container and the rolling media, wherein the rolling media are mixed with each other as the container is rotated and a finely powdered raw material in a fluid state containing fine powder and a liquid component is supplied from a raw material discharge pipe.

Abstract: Powder of ceramic materials is produced by mixing a powder of a basic ceramic composition, a solvent and a surfactant to prepare a slurry, adding at least one unsaturated fatty acid salt containing an additive metal element to the resultant slurry, polymerizing the at least one unsaturated fatty acid salt with a polymerization initiator to form a polymer of at least one unsaturated fatty acid salt, drying the resultant slurry to form a layer of the resultant polymer on particle surfaces of the basic ceramic composition, and then calcining the resultant coated powder of the basic ceramic composition.

Abstract: A heat treatment apparatus for ceramics is adapted to heat treat a ceramic raw material such as a slurry for obtaining a pulverized ceramic material. The apparatus comprises a drum body (1) which is transversely supported and rotated about its axis, and a number of rolling media (2) which are stored and stirred in the drum body (1). The drum body (1) has a pyramidal inner surface, so that the rolling media (2) are strongly stirred following rotation of the drum body (1), whereby the ceramic raw material is heat treated and pulverized effectively.