Asahi Kogaku Kogyo Kabushiki Kaisha

Toa Nenryo Kogyo Kabushiki Kaisha

Hideyuki Kuwakara

Tetsuro Ogawa

Nobuaki Tagaya

Takao Hashimoto

Tsugio Maeshima

Toshihiro Ishikawa

Noriko Komatsu

Keiko Fukamachi

A calcium-phosphate type hydroxyapatite for chromatographic separation is in the form of spherulites having a mean particle diameter of 0.5 to 50 .mu.m, preferably 1 to 10 .mu.m. The spherulites are each an aggregate mainly of acicular crystallites belonging to a series of hexagonal systems and having unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. The hydroxyapatite is produced by granulating a calcium=phosphate type hydroxyapatite in the form of a gel and then firing the granular apatite at 400.degree. to 700.degree. C., preferably at 500.degree. to 600.degree. C. The firing is performed by heating the granules in the presence of oxygen or air for a given period of time.

Calcium-phosphate type hydroxyapatite

Growing community of inventors

Oi, Japan

Hideyuki Kuwakara