In the master's theisis we observed surface events on the tablet according to the simultanious process of tablet film coating formation due to droplets spraying and drying process. To analyse the influence of the flow, the proportion of the dry matter in dispersion and initial wettness of the tablet we used measuring system for spraying droplets. It consists of spraying nozzle, optical mycroscope and fast running camera. It allowes us to monitor events on the tablet surface. Based on the process parameters in the pharmaceutical industry we determened experimental conditions of the coating. After the measurements we estimated that the flow of the dispersion and the initial state od the surface of the tablet have big influence on the droplets behaviour and consequently on film coating forming before spraying. We analysed the events durring film coating formation process with developed experimental system. The dispersion flow rate and the initial state of the tablet surface have a great influence on droplets behavior and consequently on a tablet film coating formation. Based on our measurements we estimated that an even coating is formed when we spray on the bare tablet core with 20% dispersion HPMC and flow rate of 40 g /min. Average droplets sizes are in the range of 40 to 90 μm.
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