Synthesis and Characterization of Rutile Pigments with Cr and Nb

Rutile pigments Ti1-3xCrxNb2xO2±δ (where x=0, 0.05, 0.10, 0.20, 0.30 and 0.50) prepared by solid-state reaction are investigated. Chromium is chromophore (coloring ion) and niobium is counterion (charge-compensating element for electroneutrality). The effect of composition (x), calcination temperature (850, 900, 950, 1000, 1050, 1100 and 1150°C), and starting titanium compounds (anatase TiO2, hydrated anatase paste, TiOSO4·2H2O, and hydrated Na2Ti4O9 paste) on their color properties into organic matrix and particle size distribution was observed. According to the highest chroma C and visual color evaluation, yellow and orange pigments were selected as in color the most interesting. They have concentration x=0.05 or 0.10 and are prepared from anatase TiO2 and TiOSO4·2H2O at temperature ≥1050°C