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A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is blended with mixed metal oxide pigment during synthesis. High temperature stability upto 1,100ºC is achieved by the use of this modified coating system. The purpose of this paper is to work on solar selective coating synthesis, and application of a coating as a water-borne paint is the additive key feature that helps in reduction of solvent use.

The paint was formulated using water-based system, and the main component of colorant was made by mixed metal oxide–based spinel pigment and highly temperature stable inorganic binder.

The paint formed shows excellent absorptive power with low emittance even at high temperature. Optical and thermal properties were determined along with adhesion, abrasion and other properties. The solar absorptance for these samples were as = 0.93–0.95 with corresponding thermal emittance of eT = 0.096 (at room temperature) and 0.2–0.22 (at elevated temperature 100°C).

The paint formed shows excellent absorptive power with low emittance even at high temperature. The paint can be applied in solar absorptive tower system. The obtained results indicated excellent thermal stability of prepared paint coatings. As inorganic binder was used, the paint has reduction in solvent use, and being water as a base, it is environment friendly, easy to apply and durable at high temperatures, as the binder itself is stable up to 1,500ºC.

The purpose of this paper is to synthesise X₂TiO₄ spinel‐type anticorrosion pigments and YTiO₃, perovskite‐type anticorrosion pigments, where X = Zn, Mg, Ca, Sr; Y = Ca for metal protective paints.

Anticorrosion pigments were synthesised from oxides or carbonates at high temperature. The following pigments were synthesised: TiO₂ · ZnO, 2TiO₂ · ZnO, TiO₂ · 2ZnO, TiO₂ · MgO, TiO₂ · CaO, TiO₂ · ZnO · MgO, and TiO₂ · ZnO · SrO. The pigments obtained were characterised by means of X‐ray diffraction analysis, measurement of particle sizes and scanning electron microscopy. The anticorrosion pigments synthesised were used to produce epoxy coatings with PVC = 10 per cent for each synthesised pigment. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with those of alumino zinc phosphomolybdate.

A spinel or perovskite structure was found in the pigments synthesised. High anticorrosion efficiency was identified in all the synthesised pigments, the highest efficiency being demonstrated in the TiO₂ · ZnO pigment of spinel structure and in the TiO₂ · CaO pigment of perovskite structure.

The pigments synthesised can be conveniently used to protect metal bases from corrosion.

The use of pigments synthesised in anticorrosion coatings for metal protection presents a new approach. Its benefits are the use and the method of synthesising the anticorrosion pigments that do not contain heavy metals and that are acceptable for the environment.

The iron oxide-based goethite (FeOOH) is proven to be an alternative replacement for carcinogenic chrome-based pigments. Because of its low heat stability, it tends to lose water of hydration and turns red as temperature ascends beyond 240ºC. Thus, the purpose of this paper is to increase the heat stability temperature of industrial grade (IG) goethite pigment. For this, the IG goethite pigment was surface treated with sequestrant. The properties of untreated and treated IG goethite were compared.

Three different compounds (sodium hexametaphosphate, calcium disodium ethylene diamine tetra-acetate salt, sodium gluconate) were used into the IG goethite at different concentration level. The experiments were conducted by varying the temperature and exposure time of treated and untreated samples. The total colour difference value (DE) was compared for the treated and untreated samples.

The surface treatment of IG goethite showed significant enhancement in heat stability property. From X-ray diffraction results it was confirmed that with surface treatment, there was no phase change of IG goethite even at 300ºC. Fourier transform infrared analysis states that with surface treatment when there is gradual increase in temperature from 260ºC the % transmittance of the OH (hydroxyl) deformation region band is delayed due to sequestering effect. Also, based on the total colour DE, the colour tone of surface treated IG goethite was not perceptible by human eyes even at 280ºC.

By increasing the heat stability of IG goethite, it will have increased spectrum of end usage in the high temperature coating segment. Coil coating is one of the biggest potential markets for this pigment. The increased heat stability will provide manufacturers with the option of an economical and non-toxic pigment in coil coatings and also in other sectors such as plastics, powder coatings and high temperature coatings.

The outcome of this study has been commercially implemented to produce heat stable goethite pigments in an industrial plant. The surface treated IG goethite pigments can be used in high-performance coil, powder and high temperature coatings.

The method for enhanced heat stability property of IG goethite by surface treatment with sequestrants is novel and could find numerous applications in high-performance coatings.

In this special feature details are given of those British paints which can be described as corrosion‐resistant primers, both one‐ and two‐pack. The materials are generally classified according to the base or pigment which actively prevents corrosion—e.g. metallic zinc in zinc/epoxy formulations— or by the base which produces a barrier action against corrosion, e.g. bitumen in bituminous paints. Exceptions to this are the etching primers, which are separately classified. About 300 primers are described, the manufacturers' names and addresses being cross‐indexed and listed separately on page 48.

The purpose of this paper is to describe the process of synthesizing lamellarly‐shaped anticorrosion pigments having a chemically active layer whose core consists of metal aluminium on which a thin spinel film is synthesised.

Anticorrosion pigments were synthesised by reaction of metal aluminium lamellar particles whose surface was oxidised to Al₂O₃ during the first stage and by subsequent reaction with ZnO and/or MgO at 800‐1,150°C producing a thin spinel layer that is chemically bonded to the metal core of the pigment particles. Core‐shell pigments including MgAl₂O₄/Al, Mg_0.8Zn_0.2Al₂O₄/Al, Mg_0.6Zn_0.4Al₂O₄/Al, Mg_0.4Zn_0.6Al₂O₄/Al, Mg_0.2Zn_0.8Al₂O₄/Al and ZnAl₂O₄/Al were synthesised. The prepared pigments were characterised by means of X‐ray diffraction analysis and scanning electron microscopy. The synthesised anticorrosion pigments were used to prepare epoxy coatings that were tested upon application for their anticorrosion properties and resistance against a chemical environment.

The lamellar shape of the particles, as well as good‐quality coverage with a thin spinel layer, was identified in the prepared pigments. All of the synthesised pigments exhibit good anticorrosion efficiency in epoxy coatings. Compared to lamellar kaolin and metal core of aluminium without coverage, the protective function of the synthesised pigments in coatings is demonstrably better.

The synthesised pigments find convenient applications in coatings protecting metal bases from corrosion.

Synthesis of a spinel layer on the metal core of aluminium is a novel method; so is the application of these substances in coatings designed for the protection of metals from corrosion. Of great benefit is the fact that the synthesised pigments are free of any substances harmful to the environment.

The purpose of this paper is to investigate the synthesis of calcium-based group of mixed metal oxide (MMO) pigments. The evaluation of these pigments as heat and corrosion resistant was also explored.

Two simple synthesis techniques, namely, co-precipitation and solid-state calcination method, were used to synthesise nanosized MMO pigments. And then the physico-chemical requirements according to standards for the synthesised pigments are investigated.

The prepared MMO pigments were mainly in the single phase double oxide forms. The prepared oxides exhibited good heat (up to 600°C) and corrosion resistance properties (in 5 per cent NaCl for 500 h).

This paper investigates the physico-chemical properties of synthesised calcium-based group of MMO pigments. And then evaluate it as heat and corrosion resistant paints. The simple techniques used for synthesis of nanosized MMO pigments will significantly improve the research and development of pigments’ structure and performance.

Calcium-based MMO pigments can be used as heat and corrosion resistant pigments. The easy synthesis of the mixed oxide pigments will open the door for further vital special industrial uses and applications.

Low cost, simple techniques and using naturally abundant material can be used for mass production of some other low-cost nanosized materials.

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.

The purpose of this paper is to propose a new method of synthesis of CuO · SiO₂ oxide composite based on the reaction of precipitation from water solutions of sodium silicate and copper nitrate.

Solutions of sodium silicate and copper nitrate were used as substrates. The effects of direction of substrate supply, concentration, excess of reagents and temperature of precipitation on the physicochemical properties of the products were analysed.

A new method of synthesis of CuO · SiO₂ oxide composite based on a precipitation reaction is proposed.

Only sodium silicate and copper nitrate solutions were used.

The CuO · SiO₂ oxide composite obtained can be used as blue pigment or polymer filler.

The paper determines optimum conditions of CuO · SiO₂ oxide composite precipitation to obtain products with desired physicochemical, dispersive and structural properties.