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The purpose of this paper is to conduct the directed synthesis of blue-colour aluminate spinel pigments based on spent aluminium–cobalt–molybdenum (ACM) catalyst and to study peculiar features of mineral formation processes and changes in their colour indices depending on composition and firing temperature.

Aluminate spinel ceramic pigments with specified colour indices were synthesised by directed formation of their mineral composition and identification of the most rational technological parameters of production. Mineral composition of synthesised pigments was evaluated by X-ray phase analysis. The colour indices of pigments and pigment-containing glaze coatings were studied on the comparator colour. The chemical resistance of pigments was determined by loss of their weight loss after boiling in 1 N hydrochloric acid solution and 1 N sodium hydroxide solution.

Peculiar features of formation of the mineral composition of aluminate spinel pigments based on the ACM catalyst were studied. The expediency of using magnesium and zinc oxides in their composition has been proved. It is found that for the formation of stable pigments of intense blue colour, a concentration of cobalt (II) oxide in the amount of 0.5 mol is sufficient, which is 23.1 Wt.%. The colour of such pigments is determined by the ratios of cobalt, magnesium and zinc aluminates, which form a spinel solid solution.

The use of developed aluminate spinel pigments provides obtaining of high-quality glass coatings of blue colour, in particular, for ceramics.

Aluminium oxide in the spent ACM catalyst is predominantly in the active form (of amorphous aluminium hydroxide and y-Al₂O₃). This is a prerequisite for the use of this waste material as a complete substitute for chemically pure Al₂O₃ in the technology of aluminate spinel pigments and reduction of their firing temperature. Besides, spent ACM catalyst already contains 5 Wt.% of expensive cobalt (II) oxide in the form of stable colour-bearing phase CoAl₂O₄.

This study aims to investigate the possibility of synthesizing cobalt doped willemite ceramic blue pigment by using Egyptian white sand as environmental and economical raw material for multi-applications in coatings and inks.

After the synthesis process, the prepared blue pigment was characterized via X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analysis technique. Then the blue pigment was integrated into both coating and ink formulations. The effect of the prepared multifunctional coatings on corrosion resistance and thermal stability was evaluated using different standard tests. Also, the effect of inclusion of blue pigment in flexographic printing ink formulation was done.

The results showed that the coating containing the cobalt doped willemite blue pigment offered good anticorrosive performance and high thermal stability. Additionally, the presented results revealed that integration of the blue pigment in flexographic printing ink formulation enhanced fineness, gloss, viscosity and color more than the commercial one “FX 430–201.”

In conclusion, relied on the eco-friendly principle which can be regarded as an economic and green strategy, it can be obtained that this new pigment can provide good multifunctions such as corrosion resistance and thermal stability in coatings and good fineness, gloss, viscosity and color in inks which can enable them to be widely applied in different industries.

The purpose of this paper is to synthesize and characterize nano-ceramic blue pigment Co_0.5Zn_0.5Al₂O₄ via polyacrylamide gel method. Generally, the high cost and the environmental toxicity of cobalt aluminate pigments lead them to become less common and cause problems in production process. To significantly reduce this problem, it is required to reduce the cobalt in the pigment and replace the cobalt with some amounts of zinc in the structure.

In this paper, calcination temperature and its effects on phase specification and color properties of final product were investigated. The powders were studied by using XRD, FESEM, TG/DTA, FTIR, UV-Vis and colorimetric in CIELab space, in which the calcination temperatures were set to 600°C, 800°C and 1,000 °C, and the inert atmosphere was air.

According to the XRD patterns, single-phase spinel structure with a good crystallinity was formed even in the low temperature. The infrared spectra displayed vibrations at about 500, 560 and 680 cm⁻¹, which were ascribed to the spinel structure. FESEM images showed nanoscale particles with an average size of 32 nm. Regarding the Co²⁺ spin transitions in tetrahedral sites, the UV-Vis spectra presented three bands at 552, 598 and 628 nm.

The colorimetric data indicated the formation of blue pigments corresponding to negative values of b*. The color of pigments was affected by calcination temperature.

The characterization analysis shows that a blue pigment has been obtained in this research. Different degrees of blue color were obtained at different calcination temperatures.

Pigments are fine solid particles which when exposed to light they emit different colours, depending on the nature of substances they are composed of.

The purpose of this work is to study the patterns of pigment colour formation and to develop metal compositions for obtaining spinels using the precipitation and heat treatment methods.

Precursor materials were prepared using co-precipitation method. Phase composition of pigments were determined by X-ray diffraction. Colour of pigments was determined spectrophotometry. Modelling of colour formation was performed using simplex method. Planning in the future to carry out full synthesis of pigments of blue, red and yellow colours.

The paper deals with the results of theoretical and experimental research on the synthesis pigments of blue, red and yellow colours based on Fe-Co-Al-O spinel. The influence of the chromophore cation content and the heat treatment temperature on optical and colour characteristics of pigments were studied.

The resulting composition-property diagrams make it possible to evaluate the effect of chromophore cations and heat treatment on the colour formation for Fe₂O₃-Al₂O₃-CoO system. Crystal-phase composition of the pigments is installed and its relationship with the optical colour characteristics. That makes it possible carry out targeted synthesis of pigments blue, red and yellow colours in further. The phase composition of pigments and its relationship with optical and colour properties has been established thus enabling the directed synthesis of blue, red and yellow pigments.

The purpose of this paper is to establish physical-chemical patterns and process parameters for obtaining low-temperature pink pigments with the structure of tin sphene using granulated blast-furnace slag.

Thermodynamic calculations were made in the work to assess the probability of malayaite phase formation during firing of slag-containing pigments. Mineralogical composition of synthesized pigments was evaluated by X-ray phase analysis. Spectral characteristics of pigments absorption in the infrared region were determined with the use of Fourier IR-spectrometry. Colour characteristics of the developed pigments and glass coatings with their introduction were studied on the comparator colour. Density of ceramic pigments was determined by pycnometric method, and chemical resistance was found on their weight loss after boiling in 1 N hydrochloric acid solution and 1 N sodium hydroxide solution.

Peculiar features of formation of the mineralogical composition of pink pigments are studied in the system CaO-MgO-Al₂O₃-SiO₂-SnO₂-Cr₂O₃ with the use of granulated blast-furnace slag. The end product and carrier of the pink colour is the solid solution on the basis of tin sphene. It is established that the most rational concentration of chromium (III) oxide for the formation of pink colouring of the pigments is 2 Wt.%.

The usage of developed pigments provides obtaining high-quality pink-coloured glaze coatings, in particular for ceramic tiles.

Activity of the components of blast-furnace slag in combination with the effective mineralizing action of B₂O₃ additive allows performing the firing of pink of the pigments with the formation of tin sphene at reduced temperature of 1,200°C.

The review glances upon the colorants used for printing on ceramic substrates by ink jet technology and techniques, chemistry involved during the selection of the colorants.

The ink jet technology is an easy and a convenient technique, specially designed colorants are used for such applications with tailor made properties and features.

New developments in technology and chemistry of colorants to achieve successes in application studies of ceramic substrates.

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This review glances upon the history, development and practical approach of the current techniques with available dyes and pigments and the techniques involved during the synthesis and application.

The review paper provides information about the development of the inkjet technique on ceramics and available colorants with methods.

The purpose of this study was to the low-temperature synthesis of cobalt-containing diopside pigments based on granulated blast furnace slag and to study the characteristics of the mineral formation processes, changes in the structure and colour indices.

Synthesis of cobalt-containing diopside pigments based was carried out by the directional formation of the mineralogical composition with the introduction of part of the components using granulated blast-furnace slag.

It has been established that the formation of the diopside phase in pigments containing blast-furnace slag as the main component proceeds at low temperatures (1,100°C–1,150 °C). The colour of diopside pigments is formed because of the isomorphic substitution of Si4+ ions for Al3+ ions and Mg2+ ions for Co2+ ions. It is expedient to add CoO in an amount of 0.9 mol (18 Wt.%) into the composition of diopside pigments based on blast-furnace slag to obtain defect-free violet glazes.

The developed diopside pigments enable obtaining of high-quality violet glazes for ceramics. The application of the obtained results can significantly reduce the consumption of traditional raw materials in the composition of silicate ceramic pigments, as well as reduce their firing temperature.

Calcium, magnesium and silicon oxides are the main components of blast-furnace slag. In addition, granulated blast furnace slag is mainly represented by the glassy phase, which determines its high activity during the firing process. These factors are prerequisites for using the blast-furnace slag as a valuable substitute for chemically pure or natural raw materials in silicate pigments and reducing their firing temperature.

The purpose of this study is the synthesis and characterization of a CMYK palette (cyan of Cr-BiVO₄, magenta of Pr-CeO₂, yellow of Bi-(Ce,Zr)O₂ composite and black of YMnO₃) as an eco-friendly polyfunctional palette that combines (a) high near-infrared reflectance (cool pigments) that allows moderate temperatures in indoor environments and the urban heat island effect; (b) photocatalytic activity for the degradation of organic contaminants of emerging concern of substrates in solution (such as Orange II or methylene blue) and gaseous (NO_x and volatile organic compounds such as acetaldehyde or toluene); (c) X-ray radiation attenuators associated with bismuth ions; and (d) biocidal effect combined with co-doping with bactericidal agents.

Pigments were prepared by a solid-state reaction and characterized by X-ray diffraction, diffuse reflectance spectroscopy, photocatalytic activity over Orange II and scanning electron microscopy.

The behaviour of the proposed palette was compared to that of a commercial inkjet palette, and an improvement in all functionalities was observed.

The functionalities of pigments allow the building envelope and indoor walls to exhibit temperature-moderating effects (with the additional effects of moderating global warming and increasing air conditioning efficiency), purification and disinfection of both indoor and outdoor air, and radiation attenuation.

The proposed palette and its polyfunctional characterization are novel.

Nanocrystalline cobalt spinels were synthesized under hydrothermal conditions, starting from metal chlorides. The color properties in these systems mainly depend upon the preparative method and cation distributions, which have been determined by X‐ray powder diffraction using Rietveld refinements and visible near infrared absorption spectra. We observe the influence of tetrahedral and octahedral preference of cations such as Co²⁺, Cr³⁺, Mn³⁺ upon the formation and the color development of cobalt spinel pigments. All the samples prepared revealed the formation of single spinel with particle size at about 0.8‐2.1 μm; CoAl₂O₄ reveals king's blue, CoMn₂O₄ dark blue and CoCr₂O₄ bluish green. Cobalt blues developed giving deep absorption characteristic of tetrahedral Co²⁺ ions at about 550‐680 nm; therefore, color changed from king's blue to bluish green in CoCr₂O₄, showing the absorption band of octahedral Cr³⁺ ions owing to the large excess octahedral crystal field stabilization energy.