Binders for glaze, used for both wet and dry applications, perform many functions:

1. They provide the glaze with a proper cohesive power with respect to the ceramic support (or to the other glaze layers previously applied).

The binding power is provided by the presence of organic molecules formed by functional groups capable of both binding the inorganic particles of the glaze and binding the molecules themselves when they lose water.

Binders – thanks to their ability to create a reticulation – can also significantly decrease the "dusting phenomenon" (that is, the unbound glaze that, once it loose water by evaporation, returns to dust).

2. They slow down the water evaporation and drainage process, promoting the system with a homogeneous leveling process and avoiding surface defects such as small air bubbles or pinholes.

The degree of the glaze’s adhesive (or cohesive) power also depends, on the drying and drainage times. The proper drying times of the layers that make up the ceramic body – engobe, glaze, ink, grit, covering glaze, etc. – are fundamental to ensure that each layer is applied only when the previous one has reached the correct drainage value. This is especially true in cases of glaze application on engobes.

3. They provide the glaze with homogeneity and cohesion.