Aqueous Film Coating the Current Trend

Abstract

The presentation of this work aims to update professionals involved with aqueous film coating (AFC) of pharmaceuticals on facts associated with film coating (FC) based on aqueous solvent (AS). Initially sugar coating (SC) was the first choice of pharmaceutical industry and much time and efforts were spent in perfecting the techniques and processes of SC. Long processing time and demand for operator skill as in SC compelled them to develop FC. The FC of substrate is achieved by spraying solution of diverse polymer in AS or volatile organic solvent (VOS). Initially, use of VOS in the FC is preferred over AS, as latter inherits problems like sticking, picking, over-wetting, and many more. Momentum for using AS based FC and replacing the VOS based one with the aqua based one got accelerated from last few decade for reasons like safety, toxicity, stricter regulation on environmental pollution, and economy. Nowadays coating techniques & process relies mostly on AS due to its significant benefits over VOS. Functional properties of the film-coated pharmaceuticals depends greatly on film forming polymer (FFP) along with other factors like process, equipment, technology, additives, and many others. Summarised information on technical aspect of AFCs is rare, necessitating this work. Thus information gathered, summarised, studied, and hereby is attempting to be presented in a convenience way for enriching stakeholders in the pharmaceutical field. The presentation is for updating professionals in this regard.
 Key words: Aqueous, dispersion, film-coating, latex, polymer.