Adjustment of precompression force to reduce mixing-time dependence of tablet tensile strength

The dependence of tablet tensile strength on lubricant mixing time, pre- and main compression pressure was measured with microcrystalline cellulose, dicalcium phosphate dihydrate and starch 1500 on a rotary tablet machine. Loss of tablet tensile strength arising from lubricant overmixing can be substantially reduced in the case of microcrystalline cellulose by adjustment of pre- and main compression. This facility may be used in addition to or instead of reducing mixing time, or displacing lubricant by adding extra formulation components.