In ceramics, primers are all those products – applied before the printing decoration process by means of digital printing machines – able to properly manage the ink application.

Some of them improve the ink's printing definition, some others allow you to regulate and uniform the ink absorption on the top of the surface; others increase the inks drying time. Some primers, for example, decrease the vapor pressure therefore avoiding possible condensation phenomena under the printheads of the printing machine. In this last case, the provided action is based on the ability to control the ink's absorption that leads to a better color rendering and to less printing defects.

In other words, just like in other industrial production processes, the primer has an important preparatory function. In ceramic, the primer can be applied on the surface of the glaze by means of a highly atomized spray (capable of producing a uniform application) or added directly to the glaze that is in the stirring systems of the glazing line.