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.

The study of rutile pigments Ti1−3x CrxM2x O2

Abstract This study deals with rutile pigments of type Ti1−3x Crx M2x O2 (where M = Sb, W and x = 0, 0.05, 0.10, 0.20, 0.30, 0.50) prepared by solid state reaction. Chromium is the chromophore (coloring ion); antimony and tungsten are added for achieving electroneutrality. The effect of doping elements (M = Sb, W), calcination temperature (850, 950, 1050, 1150°C) and composition (x = 0, 0.05, 0.10, 0.20, 0.30, 0.50) on color properties, particle size and electrokinetic (zeta) potential was observed. The optimal conditions for synthesis of these rutile pigments are Sb2O3 as raw material, calcination temperature 1050°C and composition x = 0.20 (Ti0.4Cr0.2Sb0.4O2). This orange-green pigment has high stable dispersion (ζ = −43.81 mV) and good color properties (chroma C = 39.50). However, brightly orange pigment Ti0.85Cr0.05W0.10O2 (x = 0.05) synthesized at temperature 1050°C gives “the finest” color with higher chroma (C = 49.48), but less stable dispersion (ζ = −37.32 mV). In light of phase composition, the optimal calcination temperature is 1150°C. Graphical abstract