6) Hygroscopicity:
Although titanium dioxide has hydrophilicity, but its hygroscopicity not very strong, and rutile type is smaller than anatase type. The hygroscopicity of titanium dioxide is related to its surface area. The large surface area and high hygroscopicity are also related to surface treatment and properties.
7) Thermal stability:
Titanium dioxide is a material with good thermal stability.
8) Grain size:
The particle size distribution of titanium dioxide is a comprehensive index, which seriously affects the performance of titanium dioxide pigment and product application performance. Therefore, the discussion on hiding power and dispersion can be directly analyzed from the particle size distribution.
The factors affecting the particle size distribution of titanium dioxide powder are complex. First, the original particle size of hydrolysis is controlled and adjusted to make the original particle size within a certain range.
The second is calcination temperature. During the calcination of metatitanic acid, the particles go through a crystal transformation period and growth period. Control the appropriate temperature to make the growth particles within a certain range.
Finally, is crushed. Usually, remoulding of Raymond mill and the adjustment of analyzer speed used to control the crushing quality. At the same time, other crushing equipment can be used, such as universal mill, air flow mill and hammer mill.