Abstract

CASTILLO, Wilmer et al. EFFECT OF SILVER ON THE MELT SYNTHESIS PROCESS OF ULTRAMARINE BLUE-TYPE PIGMENTS. Rev. LatinAm. Metal. Mater. [online]. 2011, vol.31, n.2, pp.145-149. ISSN 0255-6952.

Ultramarine blue-type inorganic pigments were synthesized using zeolite A, sodium carbonate, elemental sulphur and silver content between 0 and 5 % w/w at 800ºC for 4 h. Solids were characterized by X-ray diffraction (XRD), Fouriertransform infrared spectroscopy(FT-IR) and UV-visible reflectance spectroscopy to verify the structure and colour of obtained materials. Results showed that the silver in the mixture does not disturb the sodalite structure but the blue colour is modified in this pigment. This could be due to the formation of silver sulphur which does not allow the formation of polysulphurs responsible of the colour and the exchange of silver ions by sodium cations in the sodalite structure

Keywords : Ultramarine; Silver; Sodalite; FT-IR; XDR; Diffuse Reflectance.