The swelling force, especially the swelling force development rate, is a very important parameter in studying the effect of a disintegrant in a tablet. However, a tablet also contains diluents in most cases and the effect of diluents on the swelling force has not been studied. In this study two commonly used diluents, microcrystalline cellulose and calcium phosphate dihydrate, were investigated for their effect on the swelling force with or without a superdisintegrant, Polyplasdone XL. It was found that microcrystalline cellulose alone can develop swelling force depending on the compression force of the tablet. When combined with Polyplasdone XL, it can significantly change the swelling force of Polyplasdone XL. The effect of diluents on the swelling force is not consistent with the disintegration and dissolution studies of the tablet . 膨脹力，尤其是膨脹力發展速率，在崩散劑對錠劑的作用研究中，一直扮演著重要的角色。大部份錠劑皆含有稀釋劑，但稀釋劑的膨脹力卻一直未被研究。本研究用了兩種常見之稀釋劑microcrystalline cellulose 及 calcium phosphate dihydrate，來探討這兩種稀釋劑單獨使用時及併用超級崩散劑Polyplasdone XL 時的膨脹力。研究結果顯示microcrystalline cellulose 單獨使用時，其膨脹力會受到錠劑打錠力量的影響。當microcrystalline cellulose 與Polyplasdone XL 併用時，它會改變Polyplasdone XL 的膨脹力。但稀釋劑膨脹力的作用並未和錠劑的溶離及崩散試驗結果一致。
