The invention provides a preparation method of a
titanium dioxide
pigment with high covering power,
weather resistance and whiteness. The preparation method includes: adopting a
titanium dioxide primary product, beating in water to prepare
slurry, adding water-soluble
silicate solution as a dispersant, and performing curing prior to
grinding treatment; heating up the
slurry, adding in the water-soluble
silicate solution, adopting
mineral acid to regulate pH value, and performing curing prior to forming a dense, hydrated and unformed
silica membrane; adding the water-soluble
silicate solution again, maintaining the pH value of the
slurry with an acidic
aluminium compound, and performing curing prior to forming a loose and
porous membrane layer taking
aluminium hydrosilicate as a main ingredient so as to assure high covering power and whiteness; wrapping the loose
hydrated alumina membrane to assure excellent dispersibility; performing
filtration washing,
drying, gasification and pulverization, and recovering with a
bag filter to obtain the finished product. The preparation method has the advantages that the
titanium dioxide
pigment prepared with the method has high
weather resistance and whiteness besides excellet covering power, is high in production cost, and can be widely applied to the fields of flat and matt building coatings,
printing ink and the like with requirements on high dry covering power.