In the master's thesis we discussed the wetted surface of the tablet core. Our task was to analyse the effects of the dispersion under different conditions and parameters, when it comes in contact with the surface of the tablet core. Measurements of the wetting angle and velocity of the capillary traction of the droplet on the tablet surface were performed. With an upgraded measuring system that included a spray gun, an optical microscope and High-Speed camera, we kept track of what was happening on the surface of the tablet during the film coating process. The wetting angles of the uncoated tablet with water, were smaller than those of the uncoated tablet with HPMC. For water, they were in the range of 30–37° and for the HPMC 80–87°. The velocity of the capillary traction increases with increasing temperature and is in the range of 1,09–2,71 mm/s at three different temperatures 25 ␃, 30 ␃ in 50 ␃. Based on the measurements taken, we estimated that for the formation of film coating compositions were given next favourable conditions: atomization pressure 150 kPa, flow 40 g/min, 10 % dispersion and 50 ␃ temperature.
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