Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Takeshi Takano

Mituo Kasori

Kazuo Shinozaki

Kazuo Anzai

Akihiko Tsuge

Hiroshi Inoue

Fumio Ueno

Akihiro Horiguchi

Hironori Maki

Hiroshi Imagawa

Naohiko Ogino

Kunihide Sawamura

There is disclosed an aluminum sintered body prepared by sintering aluminum nitride and additives, which consists essentially of

Aluminum nitride sintered body

There are disclosed an aluminum sintered body comprising

Aluminum nitride sintered body and preparation thereof

An aluminum nitride-based sintered body having a high thermal conductivity and a total oxygen content of 0.01 to 20% by weight which is prepared by mixing a main component of aluminum nitride powder containing 0.001 to 7% by weight of oxygen with 0.01 to 15% by weight of at least one of the group consisting of a powder of a rare earth element and/or a powder of a material containing the rare earth element (said 0.01 to 15% by weight being counted on the basis of the content of the rare earth element), and sintering said powder mixture.

Aluminum nitride-based sintered body of high thermal conductivity

An aluminum nitride sintered body prepared by a process comprising adding to a principal component of aluminum nitride an additional component of at least one of fluorides of alkaline earth metals selected from the group consisting of calcium (Ca), strontium (Sr) and barium (Ba) or at least one of fluorides of rare earth elements added in an amount of 0.01 to 20% by weight, followed by sintering.

There is provided a multi-component system glass fiber for optical communication which comprises a multi-component system glass for core having a composition comprising SiO.sub.2, BaO, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, at least one alkali metal oxide selected from Na.sub.2 O, K.sub.2 O and Li.sub.2 O, MgO and CaO in amounts as specified in the specification and claims, and a multi-component system glass for clad layer having a composition comprising SiO.sub.2, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, at least one alkaline earth metal selected from MgO and CaO in amounts as specified in the specification and claims. The core in the glass fiber for optical communication according to the present invention shows lower optical loss and the clad layer shows high weathering resistance, and the glass fiber according to the present invention suffers from no devitrification during fiber drawing and is excellent in dimensional stability.

Multi-component glass optical fiber for optical communication

An optical fiber which consists of a multicomponent core glass member which is formed of SiO.sub.2, Al.sub.2 O.sub.3 and an alkali metal oxide and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and a multicomponent cladding glass member which is prepared from SiO.sub.2, Al.sub.2 O.sub.3, an alkali metal oxide and at least one component selected from the group consisting of ZnO, ZrO.sub.2 and TiO.sub.2, and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and consequently reduces transmission loss of light and exhibits prominent durability.

Growing community of inventors

Samukawa, Japan

Takeshi Takano