Ceramics color

This dissociated zircon is amenable to hot aqueous caustic leaching to remove the siHca in the form of soluble sodium siHcate. The remaining skeletal stmcture of zirconia is readily washed to remove residual caustic. Purity of this zirconia is direcdy related to the purity of the starting zircon since only siHca, phosphate, and trace alkaHes and alkaline earth are removed during the leach. This zirconia, and the untreated dissociated zircon, are both proposed for use in ceramic color glazes (36) (see Colorants for ceramics). 

Zirconium oxide is used in the production of ceramic colors or stains for ceramic tile and sanitary wares. Zirconia and siHca are fired together to form zircon in the presence of small amounts of other elements which are trapped in the zircon lattice to form colors such as tin—vanadium yellow, praseodymium—zircon yellow [68187-15-5] vanadium—zircon blue [12067-91 -3] iron—zircon pink [68412-79-3] indium—vanadium orange (105—108). 

Cadmium hydroxide is the anode material of Ag—Cd and Ni—Cd rechargeable storage batteries (see Batteries, secondary cells). Cadmium sulfide, selenide, and especially teUuride find utiUty in solar cells (see Solarenergy). Cadmium sulfide, Hthopone, and sulfoselenide are used as colorants (orange, yellow, red) for plastics, glass, glazes, mbber, and fireworks (see Colorants for ceramics Colorants forplastics Pigments). 

For both economic and technical reasons, the most effective way to impart color to a ceramic product is to apply a ceramic coating that contains the colorant. The most common coatings, gla2es and porcelain enamels, are vitreous in nature. Hence, most appHcations for ceramic colorants involve the coloring of a vitreous material. 

Another desirable property for a ceramic color is a high refractive index. For example, valuable pigments are based on spinels [1302-67-6] ( 2jj = 1.8) and on zircon ( 2j = 1.9), but no valuable pigments are based on apatite ( 2j = 1.6), even though the lattice of apatite is as versatile for making ionic substitutions as that of spinel. 

DCMA Classification and Chemical Description of the Mixed Metal Oxide Inorganic ColoredPigments, 2nd ed.. Metal Oxides and Ceramic Colors... 

Einbrenn-farbe, /. ceramic color, -firms, m. stoving varnish baking lacquer or enamel, -kunst, /. encaustic art. -lack, m. stoving lacquer or enamel. 

Topfer-erde, /. potter s earth, potter s clay, -erz, n. potter s ore, alquifou. -farbe, /. pottery color, ceramic color, -geschirr, >gut,... 

Both silver (m.p. 962°C, b.p. 2212°C) and gold (m.p. 1065°C, b.p. 2807°C) have characteristic brilliant white and yellow colours in bulk but when finely divided are black or, in the case of gold, can be purple, ruby red or blue. Thus reduction of gold compounds by SnCl2 gives the colloid known as Purple of Cassius , which is used as a ceramic colorant. 

Colorants, 9.T55-156. See also Colorants for ceramics Colorants for plastics Dyeing... 

Barium chromate is used as a pigment in paints, ceramics, coloring glasses, fuses, and porcelains as a corrosion inhibitor to prevent elecrochemical corrosion at the joints of dissimilar metals in safety matches in metal primers in ignition control devices in pyrotechnic compositions and as an initiator for explosives. 

Performance Materials Chemicals Color Glass Performance Materials Ceramic Glaze Coatings Ceramic Color Porcelain Enamel Fine Chemicals Intermediates Polymer Additives... 

Mixed-Metal Oxide Pigments and Ceramic Colorants... 

Colored mixed-metal oxide pigments result from the incorporation of color-giving transition metal ions into an oxide host-lattice (see Table 5.9-13). Depending upon the particle size and properties of the chosen host, pigments (0.2 to 2 pm) or ceramic colorants (stains) (up to ca. 10 pm) result, which in many cases are characterized by high thermal and chemical stability and thus are suitable for the coloring of enamels and ceramics. 

Mixed-metal oxide pigments and ceramic colorants (stains) ... 

Stains and oxides (ceramic colorants) with an average particle size up to ca. 10 pm and a broad particle size distribution, are in some cases manufactured at still higher temperature, up to 1400°C. The higher primary particle sizes are necessary because a more or less strong solubilization of the particles takes place during the firing of the enamel or ceramic frits. The component to be enameled or glazed is coated with a mixture of intensively mixed frits and colorants then fired at temperatures between 500 and 1200°C. 

Use Additive to ceramic capacitors, production of ceramic colors. 

Use Ceramic colorant, reagent in analytical chemistry, insecticide for potato plants, catalyst, purification of hydrogen, batteries and electrodes, aromatic acids from cresols, electroplating, solvent for chromic iron ores, desulfurizing oils, rayon, metallurgi-... 

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