Treated inorganic particle
View Patent ↗The disclosure provides a treated inorganic particle, in particular a titanium dioxide particle, having reduced photoactivity, lower acid solubility and improved anti-microbial properties comprising: an inorganic core particle, in particular a titanium dioxide particle; a first treatment of silica, wherein the silica is added in a single step; and a second treatment comprising co-precipitated zinc oxide and alumina. These particles have reduced photoactivity, lower acid solubility and improved anti-microbial properties.
1. A process for forming titanium dioxide particles having reduced photoactivity and improved anti-microbial properties comprising:
(a) forming an aqueous suspension of titanium dioxide core particles;
(b) depositing a first treatment of silica on the titanium dioxide core particles, wherein the silica is added in a single step;
(c) depositing a second treatment over the first treatment, said second treatment comprising co-precipitated zinc oxide and alumina; and
(d) recovering the solids, washing free from water soluble species and drying.
2. The process of claim 1 further comprising micronizing the dried particles.