Micro Crushing and Dispersibility of Titanium Dioxide
Dispersibility is an important indicator of titanium dioxide, and even the best pigments will be less effective if they are not well dispersed.
Micro crushing is the last process to control the particle size and distribution of rutile titanium dioxide. The level of process control in this process also has a significant impact on the particle size and distribution of rutile titanium dioxide, and therefore on the dispersion performance. Under the important premise of good pre-dispersion, the inorganic treatment process is one of the most critical positions. Rutile titanium dioxide can be obtained with different types of products by adopting the appropriate inorganic treatment, which includes effects on dispersibility, but also on weathering and anti-powdering properties.
After the titanium dioxide has been dry ground and crushed, most of the particles have reached a certain equivalent particle size and are then wet ground on a pre-dispersed basis. Wet grinding not only improves the efficiency of the pre-dispersion before the inorganic treatment, but also allows the shaping of the particle shape so that the particles tend to be more spherical in shape and more concentrated in distribution.
For titanium dioxide, the more spherical and concentrated the particle shape is, and the more moderate the particle size is, the better the dispersion of the product, especially as the shape and distribution of the particles have a more pronounced effect on the dispersion. Poor shape and dispersion will often result in a direct reduction in dispersion due to boundary effects that cancel out the isoelectric repulsion. Therefore, whether the dispersion is in the aqueous or the oil phase, attention needs to be paid to the various effects of the particle characteristics of the product.
