The purpose of this paper is to establish physical-chemical patterns and process parameters for obtaining low-temperature pink pigments with the structure of tin sphene using granulated blast-furnace slag.
Thermodynamic calculations were made in the work to assess the probability of malayaite phase formation during firing of slag-containing pigments. Mineralogical composition of synthesized pigments was evaluated by X-ray phase analysis. Spectral characteristics of pigments absorption in the infrared region were determined with the use of Fourier IR-spectrometry. Colour characteristics of the developed pigments and glass coatings with their introduction were studied on the comparator colour. Density of ceramic pigments was determined by pycnometric method, and chemical resistance was found on their weight loss after boiling in 1 N hydrochloric acid solution and 1 N sodium hydroxide solution.
Peculiar features of formation of the mineralogical composition of pink pigments are studied in the system CaO-MgO-Al2O3-SiO2-SnO2-Cr2O3 with the use of granulated blast-furnace slag. The end product and carrier of the pink colour is the solid solution on the basis of tin sphene. It is established that the most rational concentration of chromium (III) oxide for the formation of pink colouring of the pigments is 2 Wt.%.
The usage of developed pigments provides obtaining high-quality pink-coloured glaze coatings, in particular for ceramic tiles.
Activity of the components of blast-furnace slag in combination with the effective mineralizing action of B2O3 additive allows performing the firing of pink of the pigments with the formation of tin sphene at reduced temperature of 1,200°C.
