Achromatic power, also known as tinting power, usually it named  tinting strength for pigment,  achromatic force for tio2.

The small particle size of tio2 is conducive to uniform dispersion (0.05-0.1) and improving the color-reducing power; however, if the particle size is too small, the transparency will increase,  hiding power decreases, and the achromatic power decreases.

Influenced by:

1. IF the particle size of the filler is larger than that of titanium dioxide, tio2 reducing power decreases as per the filler quantity increases ; 

However, if the particle size of the filler is smaller than that of titanium white,  tio2 reducing power tends to increase as per the increasing of the filler amount .

2. The platy filler is more conducive to dispersion, so adding the same amount of flaky filler (talc powder, kaolin) , leading to a better dispersibility and better achromatic power than the spherical titanium dioxide with the same amount of particles.