As for the compressibility phosphoric acid three calcium agglomerate, the phosphoric acid three calcium particle, as for each it includes outside layer here, and the poly- vinyl pyrolidone where the phosphoric acid three calcium particle outside layer of 1 parts is supported at least at least on 1 parts, the binder which includes karagenan or guarugamu, it includes.圧縮性リン酸三カルシウム集塊は、リン酸三カルシウム粒子、ここでその各々は外層を含み、及びリン酸三カルシウム粒子の少なくとも1部分の外層の少なくとも1部分上に支持されたポリビニルピロリドン、カラゲナン又はグアールガムを含む結合剤、を含む。