The challenge of the film coating process
Before, during and after the film coating process, an operator has to pay attention to a lot of things. Some critical parameters must be set in advance and adjusted during the process. As our graph shows, the following factors play a key role in making the process successful:
1. Geometry of the system components
Here alone, you can turn five adjusting screws. Nozzle-to-tablet bed distance & nozzle-to-nozzle distance, distance nozzle to drum edge, spray angle and position.
2. Process temperatures
The regulation of the supply air, the temperature of the tablet bed surface and the exhaust air must be matched to the product and the spray suspension. The process air volume and spray rate are also decisive for the settings. Recommendation during the spraying process: Regularly check the tablet bed surface temperature with an IR thermometer.
3. Spray rate
It depends on the drying capacity of the system, the tablet core properties, the film properties, the solvent used and the quality of the adjustments.
4. Drum speed
The speed depends on the drum diameter, number and design of the baffles/anti-slide bars, the rolling behaviour and the abrasion tendency of the tablet cores and the fill level.
5. Suspension & Tray CoreFor each of our film coatings you will receive a processing guide that will help you to achieve a successful spraying process. In most cases, the parameters mentioned above vary if different polymers are contained in the film coating. There are differences between gastric juice-resistant, moisture-protective, retarding or taste-masking film coatings. Finally, the texture of the tablet core plays an important role. What is the abrasion resistance or brittleness? What size and shape does the tablet core have? The height of the tablet web and the radius of curvature also influence the machine settings and thus the result of the applied film coating.
In addition, there are other factors that influence the spray result for the operator. Learn more about it! BIOGRUND is happy to teach and train you. In regular coating workshops we impart not only theoretical knowledge but also practical tips on the subject of coating & tabletting. Here are our next event dates