As the name suggests, this one is one of the traditional methods of coating film or sugar on the medicine depending upon the requirements. Coating pan is utilized to create a coat around the pellets with the help of some aqueous or organic film. The components of this device include a semi ellipsoidal pan fitted with a circular cover to facilitate the charging and discharging of tablets. This pan is rotated with the help of a motor and a gear. It also has a hot air blowing unit inside which helps to vaporize the moisture content in the medicine pellet.
The main coating processes used in Pharma Companies are film coating and sugar coating. Sugar coating is the old technique to coat the bulk tablets with sugar. Sugar coating is a complex multistage process which comprise of six different steps. These steps are sealing of the tablet core, sub coating of the core, then smoothing, coloring, polishing and then the final printing.
Whereas in Film coating, there is a polymer coating outside tablets, capsules, etc. Unlike sugar coating, this type of coating is only one step process. Medicines are generally coated with a single spray using polymer, solvent, colorant or plasticizer. The solution is sprayed onto the medicine inside the rotating cover and is followed by drying. After drying the excess solvent is removed and a thin film of coating stays on the pellets.