Korean Scientists Develop Production Process for High Purity Rutile Nano Titania

Korea Research Institute of Chemical Technology (KR) researchers Sang-Il Seok, Bok-Yeop Ahn, and Hoon Kim developed a process for manufacturing titania (TiO2) nano sols, in which high-purity rutile titania nano particles are dispersed stably, through the hydrolysis of titanium tetraisopropoxide in an aqueous solution containing hydrogen peroxide and simultaneously with the hydrolysis, formation of peroxotitanate precursors, and hydrothermal treatment of them at 50-120.degree. C. The TiO2 particle size is about 30 nm, of which greater than about 99% is rutile crystals, has no ionic impurities contained at all, according to U.S. Patent 7,611,688

Titania (s stable physically and chemically and has a refractive index of greater than 2.5, which is greater than that of diamond having the greatest refractive among natural materials. If a refractive index is large in an optical material, the amount of light coming out of a medium having a low refractive index becomes large, and it is possible to reduce the size of the core in an optical waveguide and the thickness of an optical lens. Also, if highly refractive particles are dispersed in a polymer, the degree of whiteness will be increased by enhanced scattering of light. Titania is one of important industrial materials that have been used for white pigments for a long time owing to its high refraction characteristic. Further, it is one of the main components of piezoelectric materials, dielectrics, and semi-conductors according to the development of electronic industry since it is characterized by a high dielectric constant. Still further, it has been the trend recently that its application to cosmetics, photocatalytic thin layers, fillers, paints, lubricants, precision ceramics, etc. using UV shielding and absorbance properties as well as a catalyst for removing organic contaminants according to the chemical corrosion resistance and photocatalytic effect has been extended rapidly.

Titania (TiO2) nano sols patented by Korea Research Institute of Chemical Technology are applicable to electronic and optical materials with a high refractive index, high dielectric transparent insulator film materials for organic thin film transistors (OTFTs), and it can form coating films that are strong against polymers, metals, inorganic substrates even drying at a room temperature even without separate additives.