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Metallic Dye
Metal-complex dyes are a family of dyes that contain metals coordinated to the organic portion. Many azo dyes, especially those derived form naphthols, form metal complexes by complexation of one of the azo nitrogen centers. The insertion of the metal into the organic ligand often involves redox reactions, e.g. pre-reaction of sodium dichromate with glucose. Phthalocyanine Phthalocyanine () is a large, aromatic, macrocyclic, organic compound with the formula and is of theoretical or specialized interest in chemical dyes and photoelectricity. It is composed of four isoindole units linked by a ring of nitrogen atom ... (Pc) complexes, such as CuPc, are another important family of metal complex dyes.{{cite encyclopedia, title=Metal-Complex Dyes, encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry, place=Weinheim, publisher=Wiley-VCH, year=2005, author=Klaus Grychtol, Winfried Mennicke, doi=10.1002/14356007.a16_299 References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Chemistry
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azo Dyes
Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N-C linkage. Azo dyes are synthetic dyes and do not occur naturally. Most azo dyes contain only one azo group, but some dyes called "disazo dyes" contain two azo groups, some dyes called "trisazo dyes" contain three azo groups and are or more. Azo dyes comprise 60-70% of all dyes used in food and textile industries. Azo dyes are widely used to treat textiles, leather articles, and some foods. Chemically related derivatives of azo dyes include azo pigments, which are insoluble in water and other solvents. Classes Many kinds of azo dyes are known, and several classification systems exist. Some classes include disperse dyes, metal-complex dyes, reactive dyes, and substantive dyes. Also called direct dyes, substantive dyes are employed for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphthol
Naphthol may refer to: * 1-Naphthol * 2-Naphthol {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Dichromate
Sodium dichromate is the inorganic compound with the formula Na2 Cr2 O7. However, the salt is usually handled as its dihydrate Na2Cr2O7·2 H2O. Virtually all chromium ore is processed via conversion to sodium dichromate and virtually all compounds and materials based on chromium are prepared from this salt.Gerd Anger, Jost Halstenberg, Klaus Hochgeschwender, Christoph Scherhag, Ulrich Korallus, Herbert Knopf, Peter Schmidt, Manfred Ohlinger, "Chromium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. In terms of reactivity and appearance, sodium dichromate and potassium dichromate are very similar. The sodium salt is, however, around twenty times more soluble in water than the potassium salt (49 g/L at 0 °C) and its equivalent weight is also lower, which is often desirable.Freeman, F. "Sodium Dichromate" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. . Preparation Sodium dichromate is g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phthalocyanine
Phthalocyanine () is a large, aromatic, macrocyclic, organic compound with the formula and is of theoretical or specialized interest in chemical dyes and photoelectricity. It is composed of four isoindole units linked by a ring of nitrogen atoms. = has a two-dimensional geometry and a ring system consisting of 18 π-electrons. The extensive delocalization of the π-electrons affords the molecule useful properties, lending itself to applications in dyes and pigments. Metal complexes derived from , the conjugate base of , are valuable in catalysis, organic solar cells, and photodynamic therapy. Properties Phthalocyanine and derived metal complexes (MPc) tend to aggregate and, thus, have low solubility in common solvents. Benzene at 40 °C dissolves less than a milligram of or CuPc per litre. and CuPc dissolve easily in sulfuric acid due to the protonation of the nitrogen atoms bridging the pyrrole rings. Many phthalocyanine compounds are, thermally, very stabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carmine
Carmine ()also called cochineal (when it is extracted from the cochineal insect), cochineal extract, crimson lake, or carmine lake is a pigment of a bright-red color obtained from the aluminium complex derived from carminic acid. Specific code names for the pigment include natural red 4, C.I. 75470, or E120. ''Carmine'' is also a general term for a particularly deep-red color. Etymology The English word "carmine" is derived from the French word ''carmin'' (12th century), from Medieval Latin ''carminium'', from Persian ''qirmiz'' ("crimson"), which itself derives from Middle Persian ''carmir'' ("red, crimson"). The Persian term ''carmir'' is likely cognate with Sanskrit ''krimiga'' ("insect-produced"), from ''krmi'' ("worm, insect"). The Persian word for "worm, insect" is ''kirm'', and in Iran (Persia) the red colorant carmine was extracted from the bodies of dead female insects such as ''Kermes vermilio'' and cochineal. The form of the term may also have been influen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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