Project Description
Bottom spray (Wurster)
First and foremost, the major advantage of bottom spray coating, also known as the Wurster process is a highly uniform coating, combined with optimum film quality.
Depending on the application, coating using the bottom spray process can be carried out with or without a Wurster tube.
To achieve controlled release of active substances/active ingredients, the use of a Wurster tube is advantageous. It separates the particles to be coated from those already coated and undergoing drying.
What happens during bottom spray coating? The spray nozzles are integrated into the bottom plate and spray upwards from below. Combining the air distributor plate and the riser tube produces targeted and controlled particle movement: This ensures the precise and desired application of coating materials to the particle surfaces.
uniform particle residence times in the spray zone ensure consistent film quality
the high particle velocity in the riser tube prevents particles from sticking together when wet; this allows us to coat even very small particles without agglomeration
