The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 1994
Filed:
Jan. 14, 1993
Yasuharu Hakamatsuka, Tokyo, JP;
Hiroyuki Irie, Tokyo, JP;
Sukezo Kawamura, Inuyama, JP;
Motohiro Toriyama, Kasugai, JP;
Director-General of Agency of Industrial Science and Technology, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
Powdery calcium carbonate and a powdery dihydrate of calcium monohydrogenohosphate are weighed to get a Ca/P ratio of 1.45 to 1.67. The powdery mixture thus prepared is then added pure water at a temperature of 30.degree. C. or higher to obtain an aqueous slurry having a concentration of about 10% by weight. Thereafter, the aqueous slurry is subjected to a rotational attrition by using a ball mill to conduct a mechanochemical reaction of the calcium carbonate with the dihydrate of calcium monohydrogenphosphate. The slurry is then dried completely at 80.degree. C., followed by pulverization to yield a dry powder of calcium phosphate hydrate. The dry powder is calcinated at a temperature ranging from 720.degree. to 1,150.degree. C. for 1-10 hours or more to give calcium phosphate powder, which is molded in a desired shape and is sintered at a certain temperature to obtain a sintered body of calcium phosphate. The calcium phosphate and the sintered body thereof, thus prepared, have an assured biological safety in that the calcium phosphate is free from hemolysis, antigenicity and cytotoxicity.