Research Article Synthesis and Characterization of Rutile Pigments with Cr and Nb Jan VeIela, 1 Iveta Šedová, 1 Petr Mikulášek, 2 and Petra Šulcová 1 1 Department of Inorganic Technology, Faculty of Chemical Technology, University of Pardubice, Studentsk´ a 573, 53210 Pardubice, Czech Republic 2 Institute of Environmental and Chemical Engineering, Faculty of Chemical Technology, University of Pardubice, Studentsk´ a 573, 53210 Pardubice, Czech Republic Correspondence should be addressed to Jan Veˇ ceˇ ra; jan.vecera@student.upce.cz Received 29 May 2014; Revised 7 August 2014; Accepted 19 August 2014; Published 2 September 2014 Academic Editor: Roman Boˇ ca Copyright © 2014 Jan Veˇ ceˇ ra et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Rutile pigments Ti 1−3 Cr  Nb 2 O 2± (where =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). he efect of composition (x), calcination temperature (850, 900, 950, 1000, 1050, 1100 and 1150 ∘ C), and starting titanium compounds (anatase TiO 2 , hydrated anatase paste, TiOSO 4 ⋅2H 2 O, and hydrated Na 2 Ti 4 O 9 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. hey have concentration  = 0.05 or 0.10 and are prepared from anatase TiO 2 and TiOSO 4 ⋅2H 2 O at temperature ≥1050 ∘ C. 1. Introduction he goal of this work was to evaluate the inluence of com- position (=0, 0.05, 0.10, 0.20, 0.30, and 0.50), calcination temperature (850, 900, 950, 1000, 1050, 1100, and 1150 ∘ C), and starting titanium compounds (anatase TiO 2 , hydrated anatase paste, TiOSO 4 ⋅2H 2 O, and hydrated Na 2 Ti 4 O 9 paste) on color properties and particle size distribution of the rutile pigments Ti 1−3 Cr  Nb 2 O 2± into organic matrix. Sb is the most widely used charge-compensating element for commercial rutile pigments, but it is ecologically problematic. his is the reason why we studied rutile pigments with Nb, which can also ofer interesting pigments. Raw materials have an efect on properties of pigments as well; therefore, four various starting titanium compounds were used. In addition, selected pigments were analyzed by X-ray powder difraction. Rutile pigments are commercially manufactured pig- ments based on tetragonal mineral rutile (TiO 2 ) and they belong to the most important group of complex inorganic color pigments (CICPs) [1]. hey are used for coloring ceramic glazes and porcelain enamels, plastics, inks, building materials, external paints, foods, and so forth [2, 3]. Solid solutions of chromium- (III) doped rutile have gained considerable recognition as durable, chemical resis- tant inorganic pigments with thermal stability over 1000 ∘ C [4]. he crystal structure of rutile pigments is modiied by doping elements (chromophores and counterions), which vary the cell parameters [5]. In 1962, Hund issued a patent on the preparation of rutile pigments, which demonstrates the ability of rutile to form solid solutions with many compounds. hree fundamental rules were given for the formation of a rutile pigment. Firstly, substitutional atoms must have ionic sizes similar to Ti 4+ (0.61 ˚ A) or O 2− (1.40 ˚ A). Secondly, charge balance (electroneutrality) should be maintained and, thirdly, the cation: anion ratio should remain at 1 : 2, as in TiO 2 . he last two rules require the use of at least two dopants for the commercial pigments [3, 6]. Industrial rutile pigments are manufactured using several chromophores (coloring ions) with oxidation state lower than 4+; for example, Ni 2+ gives yellow hue, Mn 2+ brown, Cr 3+ from yellowish-brown to orange, and V 3+ from grey to black. A second element (the so-called counterion, that is, Sb 5+ , Nb 5+ , Mo 6+ , or W 6+ ) with oxidation state higher than 4+ is Hindawi Publishing Corporation Journal of Inorganic Chemistry Volume 2014, Article ID 705493, 8 pages http://dx.doi.org/10.1155/2014/705493