1976 Volume 25 Issue 274 Pages 671-674
There are few reports published on the state of pore distribution in tablets. Using a tablet machine and a compression testing instrument, the relation between the ejecting conditions and the pore distribution of tablets has been investigated and the following conclusion was obtained.
The total volume of pores having 103∼104Å radius in the center of tablets was greater than that in the edge of tablets. Furthermore the similar phenomenon was observed when the powder was slowly compacted and then subjected to tensile stress.
As for the tablets with less capping tendency, the total volume of pores in the center of tablets was comparatively reduced when the tablets were ejected with the suitable compressing force retained. Consequently, the effect of applied force was considered to give sufficient relaxation of stress, such as tensile stress, to the tablet during ejection.