ABSTRACT
In Brazil, studies on ceramic pigments are still very scarce. For this reason, most of the pigments consumed by the ceramic industry are imported to European countries. Another part of these pigments is obtained by the ceramic route, however, this route of synthesis results in pigments with very heterogeneous properties, reducing the quality of the coating. For this reason, several studies are aimed at developing synthetic routes that result in pigments with more homogenous properties, being environmentally friendly and economically viable. In context, the aim of this work was to synthesize oxides with perovskite structure of LaAl1-xCrxO3 composition (x = 0.1; x = 0.05) by the gelatin method, aiming its application as pigment for color transparent glazes. The powders resulting from the synthesis process were calcined at 800 and 1000 °C. Then they were characterized using thermal analysis, X-ray diffraction, UV–visible diffuse reflectance spectroscopy and CIElab colorimetry. The perovskite was used for the preparation of ceramic glazes by addition of 2 wt.% pigments on transparent glazes. X-ray patterns revealed single-phase powders with trigonal perovskite structure. The color of the samples varied as a function of the substituent content. The reddish hue was observed in the perovskites obtained with lower substitution of the Cr3+ ion and calcined at higher temperatures. No changes in the pigment color when introduced into transparent glazes were observed.
Keywords
Aluminates; Doping; Perovskite; Gelatin
