Glaze Formulation Research Articles

Technological aspects and requirements to raw materials for increasing the nutritional value of glaze

Glaze, giving confectionery products an aesthetically attractive appearance, provides the possibility of prolonging their shelf life. The main raw components of the glaze are sugar and fat, which determines its high caloric content. Modern trends dictate the need to create confectionery products enriched with essential nutrients found in vegetables, berries and fruits. The introduction of finely ground additives in the form of fruit and vegetable powder into the glaze formulation may entail changes in the rheological and crystallization properties of the glaze. The aim of the research is to develop technological methods of fruit and vegetable confectionery glaze production with increased content of dietary fibers and reduced amount of added sugar, as well as to establish requirements for fruit and vegetable powders as raw materials used in the production of confectionery glaze. The objects of the research were industrial samples of fruit and vegetable powders from raspberry, apple, carrot and beet, as well as samples of confectionery glaze produced in laboratory conditions. Common and special research methods were used in the work. The technological acceptability of using fruit and vegetable powders in the production of confectionery glaze according to their physical and chemical parameters has been determined. The yield stress of the glaze increased as the content of fruit and vegetable powder increased from 3 to 15% to varying degrees depending on its fat-absorbing capacity. The crystallization characteristic of the glaze changed: the solidification temperature decreased by 1-2 °C, the crystallization duration increased by 27-40% compared to the control sample. The nomenclature is substantiated and numerical values of quality criteria of fruit and vegetable powders to ensure technological properties of glaze are given. The influence of step-by-step introduction of surfactants on the value of yield stress of confectionery glazes with fruit and vegetable powders is shown. The technology of fruit and vegetable confectionery glaze with a high content of dietary fiber (9 g/100 g) and with a reduced amount of added sugar has been developed.

Derivation of Glaze from Cathode Ray Tubes (CRTs) for Ceramic Wares

Introduction of digital display makes cathode ray tube to be largely obsolete. The tube with its screen becomes waste at the end of the products lifecycle. This study, which combined laboratory experimentation and studio practices, aimed at production of glass glaze with cathode ray tube screen. Cathode ray tubes of four different colours were used for the study. The tubes were washed, pulverized and sieved according to their colour, elementally analysed using Particle Induce X-ray Emission, and milled into two batches per colour with first batch mixed with ball clay and second batch mixed with ball clay and additive chemical material of borax. The glaze batches were applied on eight bisque-fired tiles and fired at 1100 0C. The glazes yielded greenish grey, greyish purple, transparent grey and dark grey. This is significance towards the diversification of Nigeria’s economy for solving solid waste disposal challenges for a better and safe environment. The study has proven that cathode ray tubes with addition of borax and ball clay are suitable for glaze production and provided elemental information to guide the glaze formulation.

Frit-Free solar reflective porcelain stoneware ceramic tiles using recycled granite Waste: An investigation on its engobe and glaze formulations

The design of tiles can accelerate the transition of urban environments towards sustainability when building materials are prepared with sustainable, indigenous, renewable or recycled resources and additionally, present solar reflective properties for mitigating the Urban Heat Island (UHI) phenomenon. Here, an innovative approach to develop frit-free ceramics having solar reflectance property using locally sourced recycled granite waste was explored. The investigation unfolds in three parts: (i), the formulations were tailored for the engobe or glaze by varying raw material proportions; (ii), the solar reflectance was improved using whitening agents; and (iii), the selected formulations were subjected to an industrial trial casting of porcelain stoneware tiles. The full replacement of nepheline and feldspar with recycled granite powder offered properties suitable for the engobe such as a matte surface with high roughness and low gloss, while the same was identified to be less suitable in the glaze. The glaze formulation without any industrial frits was achieved by altering the proportions of nepheline and feldspar in the matrix. The solar reflectance of the engobe was enhanced by adding 10% of fine-grained zircon. The industrial trial showed that the developed formulation retained its conventional characteristics and superior functional performance in stain and chemical resistance.

Correlating the physico-chemical properties of two conventional glazed porcelain stoneware tiles in relation to cleanability and sanitization

Keeping surfaces clean can reduce the spread of infections. In particular, to decrease the potential for SARS CoV-2 contamination, performing disinfection of high-touching surfaces. Several ceramic tiles and porcelain stoneware tiles with antimicrobial properties are already available on the market. However, the widespread use of antimicrobial glazed stoneware tiles may require to replace the ceramic surfaces already present in many buildings. The unfeasibility of such replacement can be due to both product durability (lifetime of a tile is usually long) and/or monetary restrictions. Furthermore, as porcelain stoneware per se does not have antimicrobial activity, these materials are fabricated by adding chemical agents able to provide antimicrobial properties. This approach requires a compatibility between the antimicrobial agents and the glaze formulation, as well as a careful control of the firing cycle and the final properties of the ceramic products. It follows that the final cost of antimicrobial tiles is not competitive with that of conventional tiles. In the latter, the persistence of potential pathogens on the surfaces is a crucial problem to face: the longer a pathogen survives on a surface, the longer it may be a source of transmission and thus endanger susceptible subjects. In this work, bacteria's capacity to adhere and to be effectively removed from two conventional glazed porcelain stoneware tiles (under dirty and clean conditions) was investigated. Two different glazes were tested, one mainly glassy (glossy) and the other mainly crystalline (matt). The sanitization procedures were carried out by chemical and chemo-mechanical procedures. The results showed that chemo-mechanical sanitization was the most effective, and the best results could be obtained on the stoneware tiles coated with the mainly glassy glaze, with the lowest porosity and the lower roughness values and water contact angles, especially under clean conditions.

Case Study of Ceramic Firing Profile for Terracotta-Based Glaze

Terracotta clay is a natural resource that has the potential as a raw material in the ceramic field. This study investigates the effects of color glaze using terracotta clay powder as an alternative substance for ceramic colorants in glaze formulation. Terracotta clay powder is proportionately added to glaze formulations to determine the potential for color added to the glaze at temperatures ranging from 1140 °C to 1200 °C. The content in terracotta clay is bounded with potash feldspar, silica, zinc oxide, and calcium carbonate. Results show the apparent color of the surface on the ceramic glaze samples with different effects.

The use of boron based materials on efficiency of environmentally friendly porous ceramics

In this study, the use of boron-based materials on efficiency of environmentally friendly porous ceramics was investigated. In this context, a glaze formulation was created that uses high amounts of frit and sintered at low temperatures. Boric acid and colemanite were added to glaze formulations and different alternative formulations were created by reducing the frit percentage. These materials were added to these glaze formulations in two different ways, calcined and raw. The glaze mixtures obtained from the formulations were applied on the ceramic body and fired at 950-1000-1020-1100-1200 °C in the laboratory oven. Crystal phase structures of glaze samples containing boric acid and colemanite were analyzed by X-Ray Crystallography (XRD) method. The surface properties and characterizations of the obtained samples were examined by scanning electron microscopy (SEM). Differential Thermal Analysis and Thermogravimetric analysis (DTA/TG) were performed to determine their thermal behavior and mass loss. As a result of the analysis, it was observed that boron derivatives are a good flux agent and do not have a negative effect on the surface and other technical properties of the glaze. In the formulations of glazes with high frit content and processed at low temperatures, the percentage of frit has been reduced and costs have been improved. Also, energy costs were improved with the reduction in firing temperatures. Considering the energy and raw material costs of this study, it is predicted that high efficiency will be achieved in the process.

Elemental Comparison of Bones of Red Sokoto (Capra Hiracus) and West African Dwarf (Capra Aeagurus) Goats for Production of Glazes

Elemental characterization of glaze materials has not been of scholarly concern, especially in Nigeria where studies have also excluded animal by-products for glaze derivation and glaze modeling. This study therefore elementally examined ashes of bones of Capra hiracus (Red Sokoto Goats) and Capra aeagurus (West African Dwarf Goats) and produced glazes with them with a view to providing scientific modeling of the glazes. Raw bone samples of each animal were separately collected processed into ashes and analysed using particle induce X-ray emission (PIXE) and Rutherford Backscattering spectroscopic (RBS) techniques. Thirteen elements Magnesium, Aluminum, Silicon, Cholrine, Phosphorus, Potassium, Calcium, Titanium, Copper, Zinc, Lead and Iron (Mg, Al, Si, Cl, P, K, Ca, Ti, Cu, Zn, Pb and Fe) were determined and based on which the ashes of each sample with adobe clay, whiting, borax and soda ash were successfully modeled into five glaze batches, applied on bisque wares and fired up to 1150 0C in a down-draught kiln. Undiluted ash samples gave white and off-white colours. Their mixtures with other materials gave sienna and brown-ochre colours with opaque effect. In other words, the final glaze effects of the ashes were opaque. Visually, WAD combination was most successful, though with pocket of crazing, crawling and peeling off hosts. Conclusively, it is the hope of this article, that its finding will provoke further studies on comparative examination of animal by-products for glaze formulation, theorization and practical application.

Reuse of glass waste in the manufacture of ceramic tableware glazes

Today, various studies are carried out to spread the understanding of sustainability. The sustainability of production processes gains importance in corporate areas. In this study, the use of glass waste instead of frit used in glaze compositions in the ceramic industry was evaluated. The chemical and physical properties of glass wastes on samples were examined. The glaze formulations were prepared using 3%, 5%, and 8% by weight of glass waste instead of frit. Glass wastes were added to glaze compositions and 12 different glaze formulation studies were carried out. Transparent, Opaque, and Matte test glazes were prepared with glass waste added glaze formulations, and these glazes were applied to ceramic bodies. SEM (scanning electron microscope) analysis of standard glaze and glass waste added glazes was performed to determine the microstructural and morphological characterizations. Also, surface whiteness, brightness, L*a*b values, glaze flows, harcort test results, and final water absorption values were compared. As a result of the studies, it has been determined that it is appropriate to use 3% glass waste by weight instead of the frit in the production of ceramic tableware.

Novel light-weight glass-ceramic proppants based on frits for hydraulic fracturing process

High strength proppants were always in demand for hydraulic fracturing techniques used in unconventional reservoirs for oil and gas extraction processes. To support this concept, relatively low-alumina content glass-ceramic proppants based on the system Fe2O3–TiO2–MgO–CaO–SiO2–Al2O3 have been prepared by using frit, kaolin, and bentonite in a glaze formulation. By deposition of glaze drops on porous ceramic tile, a semi-dry proppant beads were obtained. Different frit compositions of aluminum oxide replacing calcium oxide were used to obtain highly sintered proppants with a robust glassy matrix at 1100 °C in a fast firing cycle. The microstructure by scanning electron microscopy (SEM) and the phase structure by X-ray diffraction (XRD) were investigated. The results revealed the formation of two main phases; cristobalite and calcium aluminum silicate in addition to the other two phases of mullite and Diopside ferrian in some samples. By evaluating the employed fabricated ceramic compositions as high conductivity and high strength proppants for hydraulic fracturing process it was found that all samples exhibited competitive properties according to American Petroleum Institute standards (API RP 19C Standard) for proppants criteria. Crushing loss under 7500 psi closed pressure was (from 1.5% to 6.7%), the weight loss by acids attack was (from 0.001% to 0.07%), sphericity and roundness were (0.9) in addition, the apparent and bulk densities were (from 2.51 to 2.58 g/cm³) and (from 1.46 to 1.50 g/cm³), respectively.

The effect of granulated lead–zinc slag on aesthetic and microstructural properties of single-fired wall tile glazes

Recycling of industrial wastes could reduce environmental pollution and decrease final production costs for the relevant sectors. Some of the solid wastes originating from metal production industries, including slags, scraps or powders, have been recently recognised as potential secondary raw materials to use in ceramic and glass industries for the production of pigments, bodies or glazes. The aim of this study is to produce some pigments from granulated waste slags obtained from lead–zinc smelting furnace for industrial ceramic glaze application. The chemical and phase analysis of slag is characterised by X-ray fluorescence (XRF) and X-ray diffraction (XRD), respectively. The wastes are calcinated to investigate the colour effect of synthesised pigments in industrial wall tile glazes. After addition of 5, 10 and 15 wt% of Fe2O3 to the slag, the samples were calcinated at 1150 °C and then added to the glaze composition in 3, 6, and 9 wt%, respectively. The glazes were applied to the engobed wall tiles and single fast fired at 1112 °C for 45 min. After performing colour analysis on glazed surfaces, phase analysis was carried out by X-ray diffractometer (XRD). Thermo-mechanical analyses (TMA) were done to determine the coefficient of thermal expansion (α). Increasing the proportion of slag in the glaze formulation resulted in the colour tone change of the final surfaces from cream to dark brown.

Utilization of Hard Rock Dust in Ceramic Glaze Formulation

The research focuses on the utilization of hard rock dust for formulating ceramic glazes. The rock dust was collected from Maddhapara Granite Mining area, Dinajpur, Bangladesh. Chemical compositions of raw materials were analyzed by XRF. Rock dust is characterized by high SiO2, K2O, and Na2O with low content of ferromagnesian element. For Rock dust minor amounts of components may be presents, which will mostly affect the color of the fired product (Fe2O3, MnO, TiO2, Cr2O3).Others (MgO, K2O, Na2O) will act as fluxes and may have a strong effect during sintering. Ceramic glazes containing up to 30 wt% rock dust were prepared. The glaze slurries were applied onto ceramic tiles, which were sintered at 1050 to 1100°C with slow and rapid heating rate. Different glaze mixtures containing rock dust were prepared and analyzed for micro hardness and glossiness. Microstructures of the ceramic glaze were observed by FESEM (Field emission scanning electron microscopy). The results indicated that the properties of ceramic glaze were better sintering with slow heating rate and confirmed that dust can be used in glaze formulation. Therefore utilization of hard rock dust in glaze formulation may be new possibility for recycling and conserving natural resources.

Cathode-Ray Tube panel glass replaces frit in transparent glazes for ceramic tiles

The disposal of Cathode Ray Tubes (CRT) from end-of-life personal computers and TV screens represents a serious problem in electronic-waste management. As an assembly of different materials, finding a use for each of a monitor's parts is a critical step forward a solution. However, the CRT panel is a silicate glass with a relatively high proportion of alkaline and alkaline-earth oxides, for which recycling is a natural task, and the replacement of frit in ceramic glazes arises as an interesting alternative. In this context, we investigated the effect of CRT panel glass in glazes for ceramic tiles based on a comparative analysis. We replaced up to 40 wt% of commercial transparent frit with CRT panel glass in the formulation of one reference slurry. Chemical analyses were conducted by X-ray fluorescence (XRF) and inductively coupled plasma optical emission (ICP-OES) spectrometry. The thermal expansion coefficient and the glass transition and dilatometric softening temperatures were characterized by dilatometry and compared to such properties calculated as a function of composition, using the SciGlass software and database. 20- and 30-min firing cycles were applied in a fast-firing roller kiln, replicating industrial conditions. The samples transparency was measured by spectrophotometry and compared to the colorimetric parameters of a standard glaze. The maximum content of panel glass possible to add in the transparent glaze formulation without affecting the expected properties was 20 wt%, above which transparency decreased due to heterogeneities. The reformulation of a ceramic glaze with waste CRT panel glass was successful, thus suggesting an interesting approach for disposal of other electronic wastes.

Application of statistical design of experiments for the optimization of floor tile glaze formulation

This paper investigates the influence of the various parameters on the quality of industrial Iranian floor tile glaze by using the experimental designs anal-ysis, Taguchi Method. A commercial grade of engobe and green body from one of the national tile companies have been used. Three factors namely: particle size of glaze slurry, sintering time and temperature were selected to identify the influence of these factors on the quality of glaze. A Taguchi L8 Orthogonal Arrays, fractional factorial design, was used to optimize experimental trials. This approach successfully categorized the effect of each variable using only 8 experimental trials and identified the most important variables affecting this glaze making process with the analysis of variance (ANOVA). The quality control tests of floor tile such as thermal shock resis-tance, specking resistance and surface hardness were carried out according to the existing Iranian standard. The optimized samples were obtained by factorial design analysis; taking into account coarser particle size, higher temperature and less time. The optimized sample was counter checked using Taguchi method and by selecting effective factors in high levels. It was demonstrated that, the particle size of the slurry is the only significant parameter and sample with high level in particle size and temperature of sintering is the best sample according to existing standard of floor tile

Development of Decorative Ceramic Glaze from Palm Fiber Ash

Palm fiber ashes are the industrial waste which is abundantly available in Malaysia. In this study, palm fiber ash were used to produce decorative ceramic glaze. The content of minerals in the palm fiber ash were analyzed by using X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF), respectively. The formulations of glaze with different composition of raw materials were studied by adding different amount of calcium carbonate and feldspar. The glaze slurries then coated on ball clay body bisque which was obtained from Kg. Dengir and sintered at 1200 ° C for two hours.The glaze was characterized in term of its physical appearance such as type of glaze and colour. Both glossy and matte glaze produced by using different composition of glaze formulation. The presence of silica minerals (79 %) contributed to glossy surface to the glaze. It is clearly seen that the glossiness of glaze improved by increasing amount of feldspar. Feldspar acts as fluxing agent which form a glassy phase at lower temperature. In addition, the presence of small amount of iron oxide (2.2 wt.%) contributed to brown colour of glaze. An addition of calcium carbonate give effect to the colour of glaze, which change from brown to yellow colour as amount of CaCO3 increased. As a conclusion, the palm fibre ashes were highly suitable to supply abundant and cheap raw materials to produce decorative ceramic glaze.

A Case Study in Mixture Design: Multi Response Optimization of Glaze Formulation

ABSTRACTThe main purpose of this study was to optimize the glaze formulation of a company that produces vitrified products. In this type of process, the chemical composition of the glaze has a critical effect on quality indicators such as coefficient of expansion, R value, and creeping value. The procedure used in this study included design, modeling, optimization, and confirmation steps. By the selection of desired ranges of multiple responses, the optimum glaze formula that minimizes the cost was determined by Derringer-Suich optimization. The verification results for the optimum glaze formula exhibited good agreement between the regression models and experimental measurements.

Effect of Addition of Nano Zirconia in Ceramic Glazes

In this present study zirconia particles of nanometric dimensions were synthesized using sol-gel method via the starting precursors of zirconium oxy-chloride octa-hydrate (ZrOCl2.8H2O) and oxalic acid {(COOH)2.2H2O}. A transparent sol obtained was dried at 110° C for 12 hours and the dried gel was subjected to calcination at 1000°C respectively for 3 hours in order to obtain nanozirconia particles. XRD characterization reveals the presence of single phase tetragonal ZrO2 and SEM morphological characterization reveals the presence of nanosize ZrO2 particles .The particle size distribution also confirms the nanometric size range of ZrO2 particles. The obtained nanoparticles was incorporated in the glaze composition which generally is defined as a thin glassy layer on a ceramic body that results by applying a special admixture on ceramic body and by fusing at high temperature. This glaze formulation is well bounded for dry tile manufacturing process .The incorporation of the prepared nanozirconia in a typical glaze composition are well established for its excellent mechanical, thermal and good resistance to chemical attack. Addition of zirconia increases the opacity of the tiles and also enhances the brightness .In this study with the comparison of standard conventional zircon it is bound to say that particle size decreases. Moreover glaze characterizations i.e.TG-DTA, Spectrophotometer, Abrasion resistance, crazing resistance tests was studied which shows the improvement of surface characteristics which has been enhanced by using the nanoparticles. The opacity is also increased with lower dose of usage of zirconia nanoparticles.

X-ray fluorescence applied to overglaze enamel decoration on eighteenth- and nineteenth-century porcelain from central Europe

Technical and chronological aspects of overglaze enamel production at historic porcelain factories in central Europe are discussed based on studies of over 180 objects at various laboratories. Results of analyses on representative objects, carried out primarily with X-ray fluorescence spectroscopy, are presented. Examples of eighteenth- and nineteenth-century decoration by Meissen, Du Paquier, and Hausmaler painters are described in detail. The findings highlight established glaze formulation practices and enhance understanding of the dating of objects based on the detection of zinc in yellow, blue, and green glazes. This study is the first to provide extensive scientific evidence on the composition of nineteenth-century overglaze enamel colors. In particular, the research highlights the frequent co-occurrence of both eighteenth- and nineteenth-century enamel formulations on objects, underscoring the need to examine all overglaze enamel colorants on porcelains before attributing the decoration to a particular time period.

Advancing Ceramics Glaze Formulation with Existing Software Technology Using Locally Available Raw Materials in Nigeria

The application of glazes on clay-based ceramic products has been identified as one of the best form of ceramic decorations. This can be attributed to its characteristic to lend aesthetic value to ceramic products and also to render them more durable, useful and hygienic. This paper reports an investigation on the development of new ceramic glaze recipes by means of selected glaze software packages using locally available raw materials in Nigeria. For the achievement of this study, survey methods, material oxide analysis, as well as kiln firings have been used. The results established the possibility of using existing glaze software in Nigeria so as to derive new recipes from old ones by using local material analyses database. The study indicates that with recent technological solutions, local raw materials can be properly identified and maximally utilized for a nation’s industrial development and sustainable economic growth.

Isothermal corrosion testing of frit furnace refractories

In this paper, the corrosion behaviour of aluminosilicate type refractories in frit melts is studied in an isothermal corrosion test setup. A refractory brick of largely andalusite and sillimanite composition was compared to another refractory brick of mullite and sillimanite composition, both of which were made by different manufacturers for use in different frit furnaces. The industrial frit used for corrosion tests was a commercial product used in a wall tile glaze formulation. Corrosion tests conducted under isothermal conditions provide quantitative and reproducible data about the corrosion performance of refractories. In this study, tests were performed by partially immersing a 15 mm × 15 mm × 115 mm refractory specimen into a frit melt at temperatures between 1404 and 1504 °C. The effects of temperature, duration of exposure and the refractory brick type were investigated using a statistically designed set of experiments. The ANOVA (analysis of variance) table indicated that temperature and test duration were the most important factor effects, as expected. Increasing both temperature and exposure duration led to an increased amount of corrosion as measured by the cross-sectional area loss of the corroded refractory specimen. Postmortem microstructural analysis was also done on the specimens, with extensive amount of ZnO·Al 2O 3 precipitation observed along the frit–refractory interface, where crystals of mullite and alumina were also found to precipitate. Increasing the amount of exposure time and temperature produced more ZnO·Al 2O 3 precipitation. As identified by SEM-EDS analysis, mullite crystals were in the needle-like morphology, while alumina crystals were generally cubic. Additional experiments were conducted by rotating the specimens in the melt at 50 rpm of rotational speed. Due to the reduction of boundary layer thickness, more dissolution was observed from the rotated specimens. In all specimens, corrosion was more pronounced in the bond phase than through the large filler grains of mullite and andalusite.

CRT glass state of the art: A case study: Recycling in ceramic glazes

The management of electrical and electronic equipment waste (WEEE) is a significant problem of industrialized countries, in the last decades it has been noticed an appreciable increase of this residue, consisting of about 80% of television sets and computers containing end of life (EOL) cathode ray tubes (CRT). Specific technologies permit to dismantle the kinescope, obtaining different glasses with high quality level and specific chemical compositions. The presence of dangerous elements makes critical the re-use in many fields of application. The present work proposes the feasibility of CRT glass recycling in ceramic field using it into a base glaze formulation as substitute of “ceramic frits”. The study was conducted in two phases, laboratory scale in order to study the suitable glaze formulation and semi-industrial scale with the technological support of an Italian ceramic glaze producer. The glazes obtained have aesthetic and mechanical properties extremely similar to the standard ones.