Hirayama Yasuhiko C O Asahi Ko, Ikata Haruko, Ojima Satoshi, Matsuzaki Hiromi: Artificial intervertebral disc.. Asahi Optical, May 31, 1989: EP0317972-A1 (47 worldwide citation)

An artificial intervertebral disc (10) comprising a pair of end bodies (1) which are provided, on their outer surfaces, with apatite layers (4) and a medical synthetic polymeric intermediate (3) which is held between the end bodies (1) through connecting members (2).

Hirayama Yasuhiko C O Asahi Ko, Ikata Haruko, Ojima Satoshi C O Asahi Kogaku: Process for producing an apatite coated article.. Asahi Optical, July 19, 1989: EP0324143-A1 (3 worldwide citation)

An apatite coated article comprising a substrate having thereon an apatite layer which is formed by flame spraying apatite powder at from about 2,000 to 4,000 DEG C, and a process for producing such an apatite coated article.

Ichitsuka Takeshi C O Asahi Ko, Hirayama Yasuhiko C O Asahi Ko, Ogawa Tetsuro C O Asahi Kogaku: Method for producing calcium phosphate-based material.. Asahi Optical, November 17, 1988: EP0291016-A2 (2 worldwide citation)

A method for producing a calcium phosphate-based material comprising: (a) molding a calcium phosphate powder; (b) preliminarily calcining the resulting molding in a vacuum or under a reduced pressure until the relative density is 95% or more; and (c) firing the molding in air, an inert gas, or nitro ...