Rate of water within atomized powder the result after barbottina's atomization process.

The barbottina (suspension of clays, water and other raw material), once has reached the proper parameters, is processed inside the atomizer where most of water content evaporates, forming grains (or hollow spheres) containing a residual humidity that usually ranges from 5% to 7%. At this stage, the presence of residual humidity is foundamental to provide the spheres with the proper plasticity's level to be properly pressed.

Once it has been pressed, the raw tiles still keeps the same residual humidity rate and this is the reason why at this stage of the process ceramic is defined as "green", underling the presence of water. Just like freshly cut wood.

After the pressing stage, the presence of residual humidity is a problem since it negatively affects the ceramic mechanical resistance.

On the other side, a significant amount of water within the ceramic body would be critical when the material enters the kilns.

These examples explain the reason why raw tiles, before undergoing to the glazing line appilcations, must be processed inside dryers through which the rate of residual humidity is reduced to almost 0%.