Evaluation of Hydroxypropyl Cellulose and Hydroxypropyl Methyl Cellulose as Aqueous Based Film Coatings

Abstract

Aqueous solutions of hydroxypropyl cellulose and hydroxypropyl methyl cellulose were evaluated as pharmaceutical film coatings from completely water based systems. The first phase of the study was to identify suitable plasticizers for the two polymers. The second was to examine possible interactions between the polymer solutions, and new color concentrates prepared for aqueous coating systems, based on viscosity measurements. The third phase of the study was to coat tablets with the various polymer aqueous solutions, in an air suspension tower, and in a side-vented coating pan, (while establishing coating conditions for each process). The final phase of the study was to evaluate the tablets coated by the various formulations.