Improved fillers dispersion
A good dispersion of fillers and pigments is the requisite condition
to achieve good stability and to ensure a good shelf life to the finished coating system. It
also contributes to the required film properties such as opacity, colour strength,
and gloss level if needed.
The process of dispersion of the fillers and pigments encompasses operation time,
the use of the appropriate mechanical stirring equipment and the use of a dispersing
agent.
The below graph shows the benefit of using dispersing agents to make slurries. The
dispersibility is considerably facilitated allowing an increase of filler content,
while achieving easily pumpable slurries (low viscosities), so it's very important
to choose the right dispersing agent!
Figure 1: Dispersion of CaCo3 into water
Dispersing agents help properly deflocculate the fillers and pigments
and contribute to stabilize the particles thanks to electrostatic
and steric repulsions. Aggregates and agglomeration forming is therefore considerably
limited thus imparting a very good stability to the formulation with no increase
of the viscosity within time.
Figure 2: Electrostatic repulsion
Ecodis™ and Coadis™ types dispersing agents from the Coatex range are
the most recommended valuable tools facilitating the deflocculation of fillers and
pigments. The choice of the right dispersing agent is also required to optimize
the dispersion state.
Optimal dosage of dispersing agent is determined by carrying out preliminary deflocculation
curves. The lower the viscosity, the better the dispersion state and the better
the predictable
storage stability.
Figure 3: Lower viscosity with better dispersing agents
Coatex presents a large product range of dispersing agents allowing high
performance and ensuring the best stability ever for your coatings!
