Ryzhova O. Scientific foundations of colored environmentally safe glass enamel technology

The dissertation is devoted to scientific bases of technology of ecologically safe glass enamel coatings of wide color scale for steel and nonferrous metals, development of principles of regulation and forecasting of their color. The enamels of jewelry and art were obtained on the basis of the Na2O – BaO – B2O3 – SiO2 glasses. It was determined that the ionic dyes in the degree of color ability are arranged in the following sequence: CoO > NiO > CuO > K2Cr2O7 > Fe2O3. It was first established that the mechanism of silencing of transparent matrix enamel glass in the R2O–ВаО–ZnO–TiO2–Al2O3–В2О3–TiO2–SiO2 system at the introduction of МоО3 occurs due to the diffraction of light at МоО3 inclusions of 0.05–0.15 μm, which causes the effect of opalescence of white opaque coatings. The dependence of the diffuse reflection coefficient of enamel coatings on the chemical composition of frits in the form of a mathematical model was first established. It is proved that small modifying additives Fe2O3 and ZrO2 (up to 1.0 wt.%), Which are introduced into the basic composition of enamels, allow to adjust the degree of opacity of coatings and improve their optical-color characteristics. For the first time, a color modeling method has been developed that allows you to establish a specific pigment ratio by selecting the desired coating color. Lead-free enamels for non-ferrous metals have been developed, which are recommended for introduction into the production of art and jewelry in the workshop of the Museum of Ukrainian Painting (Dnipro) and at the jewelry production company of Diadema (Vinnytsia). According to the international agreement between DVNZ UDHTU and Richemont International SA Varinor SA (Delmont, Switzerland), basic enamel (fondon) and 10-color enamel glasses are manufactured and delivered to the customer. Low-fluoride light-colored enamels were introduced into the production of Novomoskovskaya posuda LLC. The results of the researches were introduced into the educational process of the Higher Education Institute of Ukrainian State University of Chemical Technology for the preparation of students in the bachelor program in the specialty 161 "Chemical technologies and engineering" in the educational program "Chemical technologies and design of products in ceramics, glass and building materials".