- Film coating for tablets are done by two methods.
- Pan Coating: Different types of pans are used for the coating of tablets. The coating solution spray with nozzle and tablets are taken in rotating pan. Due to maintain temperature spray nozzle and rotation of pan form a proper layer of film on tablets.
- Fluidized bed coating: this is advanced technique for tablets as well as granules coating.in this high pressure air supplied from bottom of chamber and maintain fuidized state f tablets and granules. Top position adjusts the nozzle droplets for coating. Spreading and drying simultaneously done.
Pan variables: pan desire (Circular), Shape of tablets (circular, spherical oval), speed (RPM), load
Spray variable: Nozzle size decides the droplets size, Nozzle height.
- Automization: Conversion of solution to droplets
- Size of nozzle
- Air capacity
Spreading: Based on gun distance and width of gun nozzle
Distance between nozzle and tablets: If increase the distance cause dry the droplets before reach the tablet cause roughness. If decrease the distance cause over wetting of tablets.
Process air variables:
- Air volume
- Capacity of container