Four calcium phosphate powder having an apatite coating, a method of manufacturing the same, four calcium-based curable composition phosphoric acid

摘要

PURPOSE:To improve hardening characteristics by forming apatite films on a Ca4(PO4)2 powder by hydration reaction treatment and mixing this powder with a specified acid aq. soln. CONSTITUTION:A fine powder of high purity Ca4(PO4)2 having about 5mum average particle size, with a reaction promotor such as citric acid added by =1wt.% if neccessary, is brought into contact with water to effect hydration reaction at 80-100 deg.C so that apatite films are formed on the surface of the fine powder particles. 100 pts.wt. of this apatite-coated Ca4(PO4)2 and 5-80 pts.wt. (as acid weight) of 30-70%, concn. acid aq. soln. are mixed to obtain the Ca4(PO4)2-base hardening compsn. The acid aq. soln. consists of a single material or a mixture of two or more materials selected from carboxylic acids included in a TCA cycle such as tartaric acid or the like, phosphoric acid, acrylic acid polymers expressed by formula I (n is 50-50000), acrylic acid-itaconic acid copolymers expressed by formula II (l is 5-10 and m is 1-5), and acrylic acid-fumaric acid copolymers expressed by formula III.