Method of preparing calcium phosphate
US5322675A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 14, 1993 |
| Grant date | Jun 21, 1994 |
| Priority date | — |
| Expiry date | Jan 14, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/327
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.