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The possibility of isovalent substitution of zinc and cobalt atoms in the structure of willemite Zn2SiO4 was studied. Ceramic pigments with a willemite structure of blue, violet, and light blue colors were synthesized. Samples of blue color were used in the manufacture of glazes. During the synthesis of the pigments, synthetic silicon oxide was replaced by natural quartz sand. The pigments were synthesized by solid-state method at a temperature of 1270°C. The physical and chemical properties of the synthesized blue pigment were determined. In addition, the pigment was tested for use in traditional glazes for the coloring of ceramic products. It was established that the obtained blue pigment provides high aesthetic and decorative characteristics at a relatively low price. [ABSTRACT FROM AUTHOR]

The effect of immersion in a coffee drink solution on the color stability of two CAD/CAM ceramic restorations was investigated in this in vitro study. To this end, zirconia-reinforced lithium silicate (ZLS) and lithium disilicate (LDS) glass-ceramic blocks were surface-treated using mechanical polishing and glazing techniques. In addition, their color was examined before and after immersion in a coffee solution using a spectrophotometer, and the color changes were evaluated. A two-way analysis of variance (ANOVA) was used to examine the color changes. The material type significantly influenced color changes (P < 0.001). After glazing and mechanical polishing, LDS exhibited considerably less color change in both groups than ZLS. In both types of ceramics, the glazed group experienced less color variation than the mechanically polished group. Color changes were clinically acceptable across all groups. The glazing surface treatment produced superior color stability than the mechanical polishing technique. LDS exhibited more color stability than ZLS in both surface treatments. [ABSTRACT FROM AUTHOR]

The results of investigations of the chemico-mineralogical and fractional compositions as well as physicochemical properties of glauconite sandstones of the Changi deposit are presented. Enrichment methods were selected and thermal activation was conducted. The coloring properties, hiding power, and oil absorption of the obtained brown and green pigments were investigated. It was been determined that this glauconite sandstone can be used as a raw material for the production of coloring pigments in the building materials industry and the manufacture of ceramic glazes at manufacturing enterprises in Uzbekistan. [ABSTRACT FROM AUTHOR]

The primary goal of this research is to determine the mechanical properties of opaque glazed ceramic tiles containing fly ash, tincal waste, and recycled red clay, including to assess if the results meet international requirements. Opaque glaze and tincal waste were the main components of all glaze compositions of four groups, which were named OG (original), FA, RC, and FC (mixture) according to the additive. The ceramic tiles were prepared by dipping the biscuits in the glaze composition and firing them at 1150°C. The water absorption of the FA, RC, and FC tiles was less than that of the OG tiles (< 0.52%) and the scratch hardness values were between 6 and 7. All the experimental groups were also resistant to thermal shock, chemicals, and staining showing high opacity (L* > 92) and having a light yellow–red color. The micro- and crystallographic structure of some selected tiles were determined by scanning electron microscopy and x-ray diffraction techniques. Zircon, diopside and augite phases were recognized. [ABSTRACT FROM AUTHOR]

The features of the surface structure of different types of ceramic are determined and their comparative characteristics are presented. The decoration of faience with colored glazes is examined and the composition of lead-free pigmented faience glaze is described. [ABSTRACT FROM AUTHOR]

The effect of the presence of water-soluble low-molecular oligomers in paint on the possibility of single high-temperature firing and on the decorative properties of coatings taking into account the type of ceramic surface (porcelain or faience), pigment makeup, and corresponding mineral fillers was studied. Differences in the color and tone of the coatings and gloss of the glaze were found for surfaces with different aluminum-silicate modulus and temperature regimes. [ABSTRACT FROM AUTHOR]

Measurements of the infrared spectra and the results of differential-thermal analysis of ceramic glaze frit are presented. The obtained data confirm the bi-phase nature of the studied frit and the presence in it of B3+ ions in triple and quaternary coordination. The presence of two phases in the studied frit — a stiff silicate frame and low-temperature borosilicate with moderate silica content— can lead to the formation of micro-liquations. [ABSTRACT FROM AUTHOR]

Research on the structure of vanadium-containing glaze coatings obtained using spent vanadium catalysts from sulfuric acid production is reported. The chemical and phase compositions of glazes are studied. The colored glazes developed can be used in enterprises producing stove tiles, majolica, and artistic ceramic articles. [ABSTRACT FROM AUTHOR]

Acompounded mixture of fritted white, bright, glass ceramic, glaze coating for household majolica in the system NaO-KO-CaO-BO-AlO-ZrO-SiO is developed. The structure of the coating is distinguished by homogeneity and uniformity of the distribution of the crystalline formations over the entire volume of the glaze. The physical and chemical properties of the glaze coating (CLTE = (50.2 - 50.5) × 10 K, thermal resistance 150°C, whiteness 80 - 82%, brightness 87 - 89%, microhardness 5350 - 5400 MPa) attest an appropriate ratio of the crystalline and glassy phases in the glass ceramic coating formed. [ABSTRACT FROM AUTHOR]

The particularities of using inclusion pigments for decorating porcelain are examined. The compositions of underglaze pigments and colored porcelain glazes based on inclusion pigments are determined. The reasons for the appearance of defects are presented and methods of eliminating defects indicated. [ABSTRACT FROM AUTHOR]

An integrated evaluation of the surface state of glazed porcelain by mechanical and optical means is made. It is shown that both methods can be used to determine the quality of a glazed surface, but they are more informative when used together. It is found that at the surface gloss is affected more by the width and not the depth of the asperities. In terms of the surface quality of feldspar glaze, samples made from hard porcelain are inferior to the sample made from bone china. [ABSTRACT FROM AUTHOR]

The results of development work on the constitution of raw compositions of transparent shiny glaze coatings used for the production of ceramic high-voltage porcelain insulators are presented. The content region of the raw components for forming defect-free coatings with the required dielectric properties is determined. [ABSTRACT FROM AUTHOR]

The results of research on the synthesis of ceramic pigments based on titanomagnetite with modifying additives zinc, magnesium, cobalt and manganese oxides are presented. X-ray phase analysis is used to determine the phase compositions of the pigments as a function of the composition and synthesis temperature. The optimal compositions and synthesis conditions of pigments are determined. [ABSTRACT FROM AUTHOR]

The characteristic structural features of porcelain articles molded by different methods are studied. It is shown that the molding method can be identified. It is noted that the structure of the molded article affects the formation of a glaze layer. It is confirmed that the structure of the finished article inherits the texture of the initial paste. [ABSTRACT FROM AUTHOR]

Black ceramic pigments based on open-hearth slag are obtained. The possibility and sequence of physicalchemical processes occurring during kilning of pigment mixes are evaluated and the nature of the color-carrying phases in the products of their heat-treatment is determined. The relation between the crystal-phase composition and the optical indicators of the slag-containing pigments is studied. It is shown that such pigments are promising for coloring various glazes. [ABSTRACT FROM AUTHOR]

A comprehensive investigation is made of the particulars of structure and phase formation in zirconium-containing frits and semi-fritted glaze coatings obtained with such frits. It is found that the high physical-chemical and decorative-aesthetic characteristics, most importantly the durability of the coatings (3 – 4), are the result of directed phase formation, a rational combination of crystalline opacifying phases and their uniform distribution in the glassy matrix, and the formation of a uniform glass crystal structure. [ABSTRACT FROM AUTHOR]

Two specimens of lake diatomites of Karelia differing by the rock-forming types of diatoms and the form, size, and degree of preservation of the valves are investigated. It is determined that the size of the valves has a large effect on the granulometric composition and physical-chemical properties of diatomites. The SiO2 content in the initial samples of diatomites is 70%. After heat-treatment and leaching it increases to 91% and the iron content decreases sharply to 0.075%. After impurities have been removed, lake diatomites are of interest for the production of sheet glass, crystal articles, glazes and enamels, silicate glasses, as well as ceramic articles. [ABSTRACT FROM AUTHOR]

A thorough investigation of the boron-containing component — colemanite — is performed. Glaze coatings using colemanite are synthesized. The optimal content of colemanite in the batch composition is 3–6%, which makes it possible to expand the interval of glaze formation by lowering the temperature at which the glassy phase appears from 1150 to 1000°C. While retaining the required physical and chemical properties, the synthesized coatings differ by high values of the aesthetic indicators: brightness — 87%, whiteness — 89%. [ABSTRACT FROM AUTHOR]

The results of investigations of colored glazes containing oxide colorants (Cr2O3, CuO, CoO, Mn2O3), added to the batch when colored frit is being melted and when the transparent glaze frit is ground, are presented. It is established that these oxides affect the LTEC, the microhardness of the glazes, and the migration of boron, aluminum, chromium, copper, cobalt, and manganese ions out of the coatings into a 4% solution of acetic acid. The relation between the structural changes occurring in colored glassy coatings and the migration of harmful substances out of them is determined. [ABSTRACT FROM AUTHOR]

The results of studying transparent glaze coatings synthesized in the system Na2O-K2O-B2O3-Al2O3 with 12.8 wt.% B2O, and 3.9 wt.% Al2O3 are described. The effect of bivalent modifier cations SrO, MgO, CaO, and their combinations on the physicochemical properties and structure of glass and glass-based coatings is investigated. The optimum composition ranges for glaze coatings that satisfy the standards on the migration of boron and aluminum into food products are identified. [ABSTRACT FROM AUTHOR]

The possibility of producing dull low-melting glazes for ceramic products to be fired according to a slow firing regime based on the system Na2O-MgO-CaO-B2O3-Al2O3-SiO2 is demonstrated. The results of studying glaze glasses and coatings by x-ray phase analysis, electron microscopy, infrared microscopy, etc. are described. A correlation between the structure and the phase composition of coatings and their qualitative characteristics is established. The main properties of synthesized dull glazes are specified. [ABSTRACT FROM AUTHOR]

The possibility of producing glaze coatings for sanitary ceramicware without using toxic compounds, such as barium carbonate and zinc white, is discussed. The regularities of variations in the physicochemical properties of glazes (luster, whiteness, microhardness, TCLE) depending on their chemical composition are identified in correlation with their structural specifics and phase composition. [ABSTRACT FROM AUTHOR]

The properties and specific features of contemporary low-melting borosilicate glazes for special and construction purposes are given. [ABSTRACT FROM AUTHOR]

A review of low-melting borosilicate glasses and glazes for majolica and pottery is presented. The data given on the compositions and properties of glasses make it possible to identify a particular composition with the required properties and locate its patent source. [ABSTRACT FROM AUTHOR]

The effect of iron oxides with a molar content of 2.5 to 35.0% (above 100%) on the properties of aluminoborosilicate glasses is investigated. The specifics of phase separation in iron-bearing glasses and their heat-treatment products and the kinetics of liquation processes are demonstrated. The valence-coordination state of iron ions and the effect of thermal treatment on this state are identified. The dependence of the physicochemical properties of glasses on their chemical composition and structure is considered. The possibility of making colored glaze coating with preset properties and textures is substantiated. [ABSTRACT FROM AUTHOR]

It is shown that spent vanadium catalysts can be used to obtain fritted colored glazes. The technological parameters for the synthesis of glaze glasses in the borosilicate system using spent vanadium catalysts are investigated, and the physical–chemical parameters of the glazes are determined. Decorative glazes with straw-color, brown, and gray tones and lustrous, mat, and semi-mat finishes have been obtained. [ABSTRACT FROM AUTHOR]

The results of synthesis of low-melting opacified glazes for household ceramics based on the system R2O– RO – B2O3 –Al2O3 –Fe2O3 – ZnO – SiO2, which possesses high heat and chemical resistance, are presented. The interrelation of the physical-chemical properties and the phase composition and structure of the coatings with different content of the flotation tailings introduced are investigated. [ABSTRACT FROM AUTHOR]

It is established that dextrin contained in cobalt-bearing paints influences the quality of decorative ceramics. The content of dextrin is responsible for the probability of such defects as paint crumbling and cobalt metallization. As the content of dextrin in a paint grows and its adhesive capacity increases, the glaze layer thickness at the sites of paint application decreases, as well as the viscosity, the wetting angle, and the porosity of glaze. It is recommended to introduce 13% dextrin into cobalt-bearing paints. [ABSTRACT FROM AUTHOR]

The corrosion resistance of refractories to frit melts applied at the Velor Nompany (city of Orel) are investigated. Based on the results of the study, it is proposed to replace the refractory MKS, which is currently used in furnaces for melting frit glazes, by the refractory material KMTs that is more resistant to frit melts. [ABSTRACT FROM AUTHOR]

The results of an integrated study of waste generated in moist and dry concentration of ferrous quartzite are presented, and their melting temperature, phase composition, and behavior in heating are identified. The possibility of using this waste as the basis or an additive in the production of wall ceramics, household articles, glaze coatings, and glass ceramic materials is established. [ABSTRACT FROM AUTHOR]

The possibility of introducing red bauxite slime into the composition of raw glaze is analyzed. Dull pigment-free glaze coatings of a black color have been developed, and the crystalline phases formed in firing of the glaze layer have been identified. [ABSTRACT FROM AUTHOR]

The structure of aluminoborosilicate glasses is considered. It is found that the coordination states of boron and aluminum in glasses may vary depending on the composition, which has a perceptible effect on the properties of glaze glasses. Significant discrepancies were found between the experimental and calculated TCLE values of such glasses, which is due to a changed content of four-coordination boron and the emergence of six-coordination aluminum. Considering these data, it is possible to predict the physicochemical properties of glaze glasses. [ABSTRACT FROM AUTHOR]

The chemical resistance of a zinc-bearing glass-ceramic glaze intended to protect refractory products made of quartz glass ceramics from alkali media is investigated. The water and acid resistance of the glaze exceeds the analogous parameters of traditional glaze glasses. The alkali resistance of quartz glass ceramics coated by the glass-ceramic glaze increases more than 4 times. [ABSTRACT FROM AUTHOR]

Pegmatite from the Chupin deposit with mica impurities which is used for the production of glaze for porcelain can be responsible for the formation of pinhole defects. It has been established that adding calcinated kaolin to cobalt feldspar glaze decreases the formation probability of this defect. [ABSTRACT FROM AUTHOR]

Engobing is used to expand the color range for the facial surface of brick. Alight-colored engobe composition has been developed, using red-fire clays followed by the addition of various pigments, to regulate color. The rheological properties of the engobe slips are studied and the quantity of electrolytes is optimized. [ABSTRACT FROM AUTHOR]

A new method of coloring glazes is proposed on the basis of improvements in the technology for obtaining brightly colored glass coatings. The method consists of a complex of physical-chemical processes (adsorption, ion-exchange, and precipitation) which already occur at the stage of preparation of the glaze slips, containing water-soluble salts of variable-valence metals, which imparts intense and uniform color and high-quality to calcined glass coatings. [ABSTRACT FROM AUTHOR]

The structure of porcelain and glazes made from Gusev deposit stone was investigated. Its positive and negative effect on the quality of porcelain articles was demonstrated. [ABSTRACT FROM AUTHOR]

The possibility of obtaining tinted glazes without the synthesis of iron-bearing pigments is considered. Fine particles of an iron-based alloy, for instance steel obtained by fine milling of metal working waste, are introduced in the glaze composition. The testing of a glaze suspension based on window glass cullet with additives of white-burning clays and finely milled carbon steel chips demonstrate that this suspension after firing yields a uniformly tinted coating. [ABSTRACT FROM AUTHOR]

A formula for white underglaze engobe is developed based on porcelain-faience waste (after the first firing) to be used on facing tiles with a dark-colored ceramic base. Applying this engobe to a dried tile ensures good sinterability of the engobe to the tile at higher temperatures of the first firing. This makes it possible to simplify the engobe composition and to improve the quality parameters of the tile itself and of the glaze coating. [ABSTRACT FROM AUTHOR]