Natural plant dyestuffs

Cochineal ka-cho- nel, ko- [MF Sp MF cochenille, ff. OSp cochinilla cochineal insect] (1582) n. Natural organic dyestuff made from the bodies of the female insect. Coccus Cacti, which lives on plants in Central and South America. The coloring principle is known as carminic acid and is generally laked. It is not fast to hght. 

G. Farbstoffe, naturliche R colorants naturels In addition to inorganic pigments, mankind has used many natural organic dyestuffs based on plants, insects and other animal sources for dyeing textiles (- textile auxiliaries) and other materials, e. g., leather and food, hair and skin. In the second... 

Textile dyes were, until the nineteenth century invention of aniline dyes, derived from biological sources plants or animals, eg, insects or, as in the case of the highly prized classical dyestuff Tyrian purple, a shellfish. Some of these natural dyes are so-caUed vat dyes, eg, indigo and Tyrian purple, in which a chemical modification after binding to the fiber results in the intended color. Some others are direct dyes, eg, walnut sheU and safflower, that can be apphed directly to the fiber. The majority, however, are mordant dyes a metal salt precipitated onto the fiber facUitates the binding of the dyestuff Aluminum, iron, and tin salts ate the most common historical mordants. The color of the dyed textile depends on the mordant used for example, cochineal is crimson when mordanted with aluminum, purple with iron, and scarlet with tin (see Dyes AND DYE INTERMEDIATES). 

Quinones are colored p-benzoquinone, for exanple, is yellow. Many occur naturally and have been used as dyes. Alizarin is a red pigment extracted from the roots of the madder plant. Its preparation from anthracene, a coal tar derivative, in 1868 was a significant step in the development of the synthetic dyestuff industry. 

Sulphuric acid is the largest volume chemical in the world with an annual production of about 180 mill, t/year which is used primarily for phosphate fertilizers, petroleum alkylation, copper ore leaching and in smaller quantities for a number of other purposes (pulp and paper, other acids, aluminium, titanium dioxide, plastics, synthetic fibres, dyestuffs, sulphonation etc.). The major sulphur sources for sulphuric acid production are sulphur recovered from hydrocarbon processing in the refineries and from desulphurisation of natural gas, SO2 from metallurgical smelter operations, spent alkylation acid, and to a minor extent mined elemental sulphur and pyrites. A simplified flow sheet of a modem double-absorption plant for sulphuric acid production from sulphur is shown in Fig. 1. 

Dichlorobenzidine does not naturally oceur in the environment (lARC 1982a). 3,3 -Diehlorobenzidine was not detected in ambient air of two dyestuff produetion plants at detection limits of 5 (Narang et al. 1982) and 0.1 ng/m (Riggin et al. 1983). More reeent data on occupational exposure levels indieate the presence of levels 0.6-2.5 g/m in 3,3 -diehlorobenzidine production and pigment manufaeturing plants in Germany (DCMA 1989). 

Paul Hermann Muller received a degree in chemistry and worked for the J. R. Geigy Corporation, which later became part of Novartis (McGrayne 2001). Geigy specialized in dyestuffs for woolens. Chemists at the company discovered a chlorinated hydrocarbon compound that protected woolens from clothes moths, but it was a stomach poison. Geigy then searched for other insecticides that killed other pests. Natural insecticides made from plants include pyrethrum from chrysanthemum, rotenone from a tropical... 

Fibers exist as natural, or synthetic, hydrophilic, hydrophobic, nonionic, and ionic. Natural fibers hnvc complex chemical structures with a multitude of possible points of attraction for a dyestuff and are difficult io characterize because of the structure being strongly influenced by regional, climatic variations and the species of plant or animal. Dyeing of natural fibers is therefore much more complex than dyeing synthetic fibers where structures can be characterized and the availability of points of attraction can be deliberately engineered into the fiher s molecular chain. The various types of liher arc summarized in Tahle I. The fiber type dictates the type of dye needed. 

Flavones. These compounds are the most widely distributed natural coloring matter formerly used as dyestuffs. Hasone-iype dyes occur in all the higher plants in the leaves, roots, bark, fruits, pollen, and flower petals. The most widespread flavone dye are quercetin and kaempferol. In general, the dyes occur as glycosides, the most common sugar being glucose. 

These discoveries were important not only because of the individual new compounds, hut also because they totally changed the nature of the dyestuff industry. Since the dawn of civilization, humans had relied on natural products (plants and animals) as dyes to color clothing and other fabrics. With the dawn of the Mauve Decade, such dyes very quickly became abundantly available at rather modest costs. 

The world textile industry is one of the largest consumers of dyestuffs. An understanding of the chemistry of textile fibers is necessary to select an appropriate dye from each of the several dye classes so that the textile product requirements for proper shade, fastness, and economics are achieved. The properties of some of the more commercially important natural and synthetic fibers are briefly discussed in this section. The natural fibers may be from plant sources (such as cotton and flax), animal sources (such as wool and silk), or chemically modified natural materials (such as rayon and acetate fibers). The synthetic fibers include nylon, polyester, acrylics, polyolefins, and spindex. The various types of fiber along with the type of dye needed are summarized in Table 8.2. 

Alizarin is one of the few natural dyestuffs which have been prepared synthetically, and is probably the only one which is prepared artificially on the large scale. It occurs generally as a glucoside, ruberythric acid CggH gOu [1, 2] in madder, the root of Rubia tincforium, and also in some other plants. 

Berberine is an alkaloid occurring in many plants, and belongs to the quinoline dyestuffs. So far as our present knowledge reaches, it is the only member of this series occurring in nature, and is also the only natural dyestuff with basic properties capable of being fixed on fibres like basic aniline dyes. 

The number of colouring-matters included in the present chapter is unfortunately very large most of them are natural products obtained from plant and animal sources. As these natural dyestuffs are very numerous, only those are described which are of interest from a technical or scientific point of view. 

ABSTRACT Quinones constitute a structurally diverse class of phenolic compounds with a w ide range of pharmacologial properties, which are the basis for different applications in the broad field of pharmacy and medicine. In traditional medicine all over the world, plants which are rich in quinones are used for the treatment of a variety of diseases. Besides the classical applications of these plants in industry (dyestuffs) and pharmaceutical (laxatives) practice, the relatively new field of biologically active quinones will be discussed. This review gives an account of the work done on naturally occurring bioactive quinones from 1992 to the present date. The biological activity detected in quinones from natural and synthetic sources has been discussed in relation to chemical structure under the respective titles. 

A national dye shortage led to initiation of an intensive research program on dye intermediates in 1916. This program was a natural extension of Du Font s experience with coal-tar crudes in compounding high explosives. Moving rapidly, the company built its first dye plant in Deepwater, New Jersey. The first fast vat dyes were produced in 1919, and by 1923 the plant was a major producer in America s newly established dyestuffs industry. 

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