Study of the photo-stability of ceramic thermal control coating based on aluminium oxide

The study examined the photo-stability of the thermal control coating (TCC), a class of "Optical Solar Reflectors", used in spacecrafts. This TCC is achieved by applying a layer of dielectric ceramic paste (DCP) onto the substrate using a printer (PCB printing). The DCP was prepared from filler (ground Al2O3 ceramic) and solvent with thickener (terpineol with ethylcellulose). The coating obtained by high-temperature firing (T = 850 C-& ocy;, 2 h) has high reflectivity in the solar range of the spectrum (0.2-2.5 mu m) with the solar absorptance (alpha(s)) of DCP equal to 0.143. It has high adhesion and photo-stability that exceeds photo-stability parameters of ZnO, TiO2, BaSO4, and CaSiO3 pigments. The developed coating can be recommended not only as a TCC for spacecrafts, but also as a protective or dielectric layer in manufacturing of printed circuit boards in various fields of technology, where increased resistance to solar radiation or its ultraviolet region is required.