Toshiba Tungaloy Co., Ltd.

Ngk Spark Plug Company, Limited

Shin-ichi Hirano

Susumu Yamaya

Shigeharu Naka

The invention provides a method of preparing .beta.-BaB.sub.2 O.sub.4 thin film. The beta barium boron thin film obtained does not contain impurities but has homogeneous structure, thus being applicable to various industrial fields including integrated circuits. The method of the invention includes the steps of melting and mixing boron alkoxide and metal barium or barium alkoxide in the presence of a solvent to prepare a homogeneous solution, covering a substrate with a thin film of the homogeneous solution or concentrated homogeneous solution, and firing the thin film in an atmosphere containing oxygen in a temperature range higher than 400.degree. C. and lower than 900.degree. C.

Manufacture of .beta.-BaB.sub.2 O.sub.4 film by a sol-gel method

There are disclosed a cubic boron nitride coated material including a substrate and an outer layer composed principally of cubic boron nitride and formed on a surface of the substrate, comprising an intermediate layer fored of at least one intermediate layer and interposed between the substrate and outer layer, the intermediate between the substrate and outer layer, the intermediate layer or the outermost one of intermediate layers being formed of a layer of at least one nitrogen-containing compound selected from the nitrides and nitroxides of Al, Ga, In and Tl and mutual solid solutions thereof, and a producing method of the same which comprises: providing, on the surface of the substrate, an intermediate layer formed of at least one intermediate layer, the intermediate layer or the outermost one of intermediate layers being formed of a layer of at least one nitrogen-containing compound selected from the group consisting of nitrides and nitroxides of Al, Ga, In and Tl and mutual solid solutions thereof; and causing the outer layer to undergo oriented growth on a face of the layer of the at least one nitrogen-containing compound, the face being densely packed with nitrogen atoms.

Method of producing cubic boron nitride coated material

A cubic boron nitride coated material comprises a substrate, an outer layer consisting essentially of cubic boron nitride and formed on a surface of the substrate, and at least one intermediate layer interposed between the substrate and outer layer, the intermediate layer comprising at least one nitrogen-containing compound selected from the nitrides and nitroxides of Al, Ga, In and Tl and mutual solid solutions thereof. Such a coated material can be produced by a method that comprises:

Cubic boron nitride coated material and producing method of the same

Disclosed is a method for preparing a sintered body containing cubic boron nitride which comprise the steps of

Method for preparing sintered body containing cubic boron nitride and

There are disclosed methods for preparing cubic boron nitride sintered body. One method involves pyrolyzing borazine and/or a borazine derivative to obtain a boron nitride; mixing said boron nitride and a catalyst composed of a metal and/or metallic compound; and reacting the mixture at a pressure of 3 GPa or more and at a temperature of 700.degree. C. or more. Another method comprises the step of pyrolyzing borazine and/or a borazine derivative to obtain a boron nitride; mixing said boron nitride and a catalyst composed of a metal and/or metallic compound; reacting the mixture at a pressure of 3 GPa or more and at a temperature of 700.degree. C. or more; and removing the catalyst from a formed product. The conversion rate into cubic boron nitride achieved with these methods is as high as 100%, and the obtained cubic boron nitride is highly pure and fine. Also disclosed is a method for preparing boron nitride by pyrolyzing at least one compound selected from the group consisting of borazine and/or a borazine derivative at a temperature of 150.degree. to 700.degree. C. and a pressure of 10 MPa or more.

Growing community of inventors

Nagoya, Japan

Shin-ichi Hirano