| 摘要 |
PURPOSE:To obtain the titled uniform powder agent having high activity, by calcining a specific hydroxyapatite under reduced pressure and forming a mixture of tricalcium alpha-phosphate and tetracalcium phosphate. CONSTITUTION:A hydroxyapatite is thermally decomposed by burning a hydroxyapatite capable of readily synthesizing by wet type method and having 1.5-1.8 Ca/P ratio at >=1,150 deg.C under reduced pressure to afford tricalcium alpha-phosphate and tetracalcium phosphate and the mixture of tricalcium alpha-phosphate and tetracalcium phosphate is obtained. Used hydroxyapatite can be readily synthesized e.g. by reacting phosphoric acid water solution with calcium hydroxide suspension. The hydroxyapatite is preferably thermally decomposed at a calcining state of 1,150-1,450 deg.C and <=10Pa pressure, especially <=10<-2>Pa pressure. |
