Optimization

Steps to improve dispersion results

In cases where the quality of dispersion does not meet the required standard, the following parameters should be checked:

Duration of the dispersion operation
The quality of formulations dispersed using a DISPERMAT® with a sufficient high‒speed generally reaches its final value after a short period of time (approximately 10 ‒15 minutes). Increasing the dispersion time to more than 20 minutes does not normally lead to improved results.

Doughnut effect
The doughnut flow pattern should be maintained during the course of the whole dispersion.

Shaft speed
The mechanical power input should be optimised by using the highest possible shaft speed whilst considering the tip speed in m/sec of the dissolver disc, without destroying the doughnut flow pattern.

Geometrical considerations
The distance between the dissolver disc and the bottom of the vessel can be changed to obtain better results and to make higher rotational speeds possible.

Amount of millbase
Better flow characteristics may be achieved by using more or less millbase in the container.

Dissolver disc
The use of smaller or larger dissolver disc may lead to better results.

Pigment and filler concentration
A high‒viscosity millbase of tacky consistency with dilatant flow is recommended this may be obtained by increasing the percentage of solids, but without destroying the doughnut flow pattern.

Flocculation
Does flocculation take place after dispersion? If so, check additives.

Temperature
When dispersing, high energy transfer into the millbase will lead to an increase in temperature. In many cases this destroys the flow characteristics of the formulation. In addition, thermally sensitive paint ingredients may be harmed. Using a water cooled vessel will solve the problem.

Raw materials
Partial re‒formulation of the paint using more suitable resins, pigments, fillers or additives: It should be kept in mind, that the DISPERMAT® is a dispersion device and not a piece of milling machinery. Therefore it is incapable of grinding primary particles down to a smaller size.

Vacuum
At a dispersion under vacuum high‒viscous products can be produced to the greatest possible extend without air bubble inclusions.

Additives
By adding suitable additives the result of the dispersion process can be strongly improved.

12. - 15.03.2024
Orlando


Int. Battery Seminar & Exhibition
Orlando, USA


Experience our dispersion technology! Know-how and top quality since 1972.

At our trade fairs, we present our latest innovations as well as a representative exhibition of patented dispersing and fine grinding systems DISPERMAT® and TORUSMILL®.

Trade fairs

USA
12. - 15.03.2024
INT. BATTERY EXHIBITION, Orlando

FRANCE
26. - 28.03.2024
EUROCOAT, Paris

USA
30.04. - 02.05.2024
AMERICAN COATINGS SHOW, Indianapolis

GERMANY
10. - 14.06.2024
ACHEMA, Frankfurt