Glidant

A glidant is a substance that is added to a powder to improve its flowability. A glidant will only work at a certain range of concentrations. Above a certain concentration, the glidant will in fact function to inhibit flowability.

In tablet manufacture, glidants are usually added just prior to compression.

Examples

Examples of glidants include ascorbyl palmitate,^[1] calcium palmitate,^[2] magnesium stearate, fumed silica (colloidal silicon dioxide), starch and talc.^[3]

Mechanism of action

A glidant's effect is due to the counter-action of factors that cause poor flowability of powders. For instance, correcting surface irregularity, reducing interparticular friction and decreasing surface charge. The result is a decrease in the angle of repose which is an indication of an enhanced powder's flowability.

References

1. KR 101440100, Kim, Dong Sup; Baik, Joo Hyun & Jung, Hyun Mook et al., "Use of ascorbyl palmitate and ascorbyl stearate as glidant for tablets", published 2014-09-17, assigned to Cosmax Bio Co. Ltd. 
2. "Vitamin & Supplement Recommendations for Your Health Concerns - Swanson®". www.swansonvitamins.com. Archived from the original on 2021-02-28. Retrieved 2021-02-05.
3. "SMI: Talc as a Glidant & Lubricant". 2012 Specialty Minerals Inc. Archived from the original on 28 August 2008. Retrieved 19 March 2014.