| 摘要 |
PURPOSE:To produce calcium hydrogenphosphate exhibiting an excellent binding property without any more modification and suitable for a vehicle for direct compression by reacting phosphoric acid with an alkaline calcium compound in the presence of a specified polyvalent organic acid in an aqueous medium. CONSTITUTION:Phosphoric acid is reacted with an alkaline calcium compound or an alkaline metal phosphate and a calcium compound in the presence of a polyvalent organic acid having a coordination force in an aqueous medium, thus producing the objective calcium hydrogenphosphate represented by formula CaHPO4.mH2O (0<=m<=2) and composed of primary particles having a prismatic crystal structure of 0.1 to 1mum particle size when observed by an electron microscope. As the polyvalent organic acid, one or more kinds of compounds selected from citric acid, tartaric acid, ethylenediaminetetraacetic acid, malic acid and succinic acid are used. |
