Tosoh Corporation

Other

Mutsumi Asano

Hideto Kuramochi

Shuji Takatoh

Tsuyoshi Tanaka

Satoshi Kondo

Toru Futami

Koyata Takahashi

Kenichi Sekimoto

Kiyoshi Kasai

Masayuki Kudo

Yoshinori Harada

Yoko Honma

Shigeru Hiramatsu

Satoshi Kondoh

Tatsuo Kawasaki

Hidehiko Misaki

Yuji Kawara

Hiroyuki Yokomizo

An abrasive molding consisting essentially of inorganic particles having an average particle diameter in the range of 0.005 &mgr;m to 0.3 &mgr;m, and having a relative density in the range of 45% to 90%, provided that pores having a diameter of at least 0.5 &mgr;m are excluded from the molding. The abrasive molding is used for polishing a material to be polished by using a polishing liquid, preferably water or an aqueous solution of an alkali metal hydroxide, which does not contain a loose abrasive grain.

Abrasive molding and abrasive disc provided with same

An optical recording medium able to reproduce address information during seeking in which an optical head moves between tracks, to increase seek speed, to improve recording/reproduction speed and to obtain a good header reproducing signal is achieved by that the concave portions or convex portions constituting a reproducing signal in seeking reproduced even during seek and/or constituting a timing signal for writing a header signal are connected to each other in a direction orthogonal to the tracks, when these concave portions and/or convex portions are placed in positions equivalent to each other in the adjacent tracks.

Optical recording medium having address pits in the header region connecting with each other

An abrasive molding composed of a mass of inorganic particles, said mass having pores intervening among the inorganic particles, which molding has abrasive area to be placed in frictional contact with an article to be abraded, and non-abrasive area on a abrading surface of the abrasive molding. The abrasive area has exposed pores having a diameter of not larger than 1 &mgr;m, the total area of said exposed pores having a diameter of not larger than 1 &mgr;m occupying below 15% of the total area of abrasive area, and the non-abrasive area occupies 20% to 60% of the sum of the abrasive area and the non-abrasive area.

An abrasive molding comprising at least 90% by weight, based on the abrasive molding, of an inorganic material having a stock hardness of 50-400 kg/mm , and said abrasive molding having a relative density of 20-70% and an average particle diameter of 0.001-50 &mgr;m. The abrasive molding preferably has pores having a pore size distribution such that the integrated pore volume of pores having a diameter of 0.01-1 &mgr;m is at least 20% of the integrated total pore volume of the entire pores, and the integrated pore volume of pores having a diameter of 1-360 &mgr;m is in the range of 10% to 70% of the integrated total pore volume of the entire pores. The abrasive molding is suitable for polishing a material having a Vickers hardness not larger than 300 kg/mm .

A magneto-optical recording medium and process for production of the same are disclosed, the magneto-recording medium comprising a substrate having thereon a magneto-optical recording film and at least one coating film provided on a light incident side and/or an opposite side thereto, of said magneto-optical recording film for protection of said magneto-optical recording film and/or Kerr effect enhancement, wherein said coating film contains silicon, nitrogen, and hydrogen as constituent elements. The magneto-optical recording medium has excellent reliability, excellent read-out performance properties as well as excellent recording sensitivity while exhibiting high magneto-optical effects and freedom from corrosion.

Magneto-optical recording medium and process for production of the same

Growing community of inventors

Sagamihara, Japan

Mutsumi Asano