INORGANIC PIGMENTS BASED ON HETEROPOLY COMPOUNDS FOR PROTECTIVE-DECORATIVE ALUMINOPHOSPHATE -BONDED COATINGS

Abstract

Inorganic pigments are synthesized in the paper. These inorganic pigments contain molybdophosphates and molybdosilicates of transition metals as chromophores, and dispersed silicates with different structural groups of silicon-oxygen tetrahedra, in particular marshalite and wollastonite, as substrates. The inorganic pigments obtained are brightly colored, highly light-stable and acid-resistant. The color of the pigments depends on the transition metal used during the synthesis process, as well as on the acid medium. The paper demonstrates the possibility of using inorganic pigments based on heteropoly compounds for protective-decorative and fire-resistant aluminophosphate-bonded coatings. X-ray diffraction (DRON-UM1 diffractometer, filtered Co Kα radiation) and IR spectroscopy (Nicolet 5700 FTIR spectrometer) show that the phases of AlPO4, Al(PO3)3 and Al(H2PO4)3, quartz (wollastonite), and pigment are contained in the alumophosphate-bonded coating. A small amount of the phase Al3(OH)3(PO4)2·H2O is detected. Thermal analysis performed using the SDTQ600 thermal analyzer shows that the structure of protective-decorative coatings is preserved at the temperatures of about 900 °C, which allows these pigments to be used for the manufacture of heat-resistant ink compounds. Optical studies (Axiovert 200M) confirms that after thermal treatment the colored coatings have a homogeneous structure that does not contain cracks and can, therefore, be used for coating both metal and concrete surfaces.