Abstract
Sticking is a common phenomenon in the manufacture of tablets in which the top of a tablet becomes pilled during compression.The effects of tableting machine temperatures on the sticking of butyl-p-hydroxybenzoate were examined. Sticking was estimated by measuring the pressure placed on a scraper (scraper pressure, or SCR). The pressure reached a maximum value at a homologous temperature of around T/Tm=0.90, where the probability of sticking is high. It was found that sticking occurs easily in materials having a low melting point and in fine particles when compression stress and temperature are constant.We also found that the x^--R control charts obtained by measuring SCR help to detect sticking. Moreover, a shear test of tablets on a temperature-controlled metal plate was carried out, and the results were similar to those of the SCR; that is, the shear strength (C) and friction coefficient (μ) reached a maximum value at T/Tm=0.90.
