TAGS: Titanium Dioxide Pigment Titanium dioxide (TiO 2) is the white pigment used to give whiteness and hiding power, also called opacity, to coatings, inks, and reason for this is twofold: TiO 2 particles of the right size scatter visible light, having wavelength λ ≈ 380 700 nm, effectively because TiO 2 has a high refractive index