Introduction
Printing inks used in ceramics are constituted of inorganic pigments dispersed in
a serigraphic liquid. This liquid gives to the ink some rheological properties
necessary for the printing process. A good stability of ink, at rest or in use, is
essential because pigments tend to settle and to aggregate. This instability leads
to evolutions of the rheological properties of the product, which can make the
application difficult or even impossible, and provoke defects in the printing.
For a given pigment, it is necessary to study the stability of the ink as a function
of the different serigraphic liquids as the aggregation can be reversible or not
due to chemical interactions between the pigment and the liquid. Depending on
the stability behaviour, the ink redispersibility can be different.
This note will show, on the example of three inks from the market, how SMLS
technology permits to characterize pigment stability and redispersibility.
