Indian. The English word aniline is also derived from anil, and it is used to describe a class of synthetic dyes. For information on the Expansion of Europe seminar, contact the curator at [email protected]
(It was not until 1883 that Baeyer finally determined the structure of indigo. The I. tinctoriaspecies was domesticated in India. Murdo J. MacLeod, Spanish Central America. As in a standard indigo dye pot, care has to be taken to avoid mixing in oxygen. powers planted indigo plantations in their tropical colonies. This is the conventional indigo colour powder. Several sources claim that ancient linen fabrics dyed blue are likely to have been dyed with indigo because indigo was … Indigo, or indigotin, is a dyestuff extracted from the indigo and woad plants. After that use of indigo rises in Europe. The association of India with indigo is reflected in the Greek word for the dye, indikón (Ἰνδικόν, Indian).  When Benjamin Franklin sailed to France in November 1776 to enlist France's support for the American Revolutionary War, 35 barrels of indigo were on board the Reprisal, the sale of which would help fund the war effort. The dye was also known to ancient civilizations in Mesopotamia, Egypt, Britain, Mesoamerica, Peru, Iran, and Africa. The related Ciba blue (5,7,5′,7′-tetrabromoindigo) is, however, of commercial value. Trade product essays have been contributed by graduate and advanced undergraduate students in the Bell Library’s Expansion of Europe seminar (Hist 5962), unless otherwise indicated. BASF developed a commercially feasible manufacturing process that was in use by 1897, at which time 19,000 tons of indigo were being produced from plant sources. It is used in the United States mainly for dyeing cotton for work clothes; for a long time it was used to produce heavy (navy blue) shades on wool. It is insoluble in water, alcohol, or ether, but soluble in DMSO, chloroform, nitrobenzene, and concentrated sulfuric acid. Spain imported the dye from its colonies in Central and South America, and it was a major crop in Haiti and Jamaica, with much or all of the labor performed by enslaved Africans and African Americans. Indigo remained a rare commodity in Europe throughout the Middle Ages. 18. The arsenic compound delayed the oxidation of the indigo long enough to paint the dye onto fabrics. They considered it a luxury product and used it for paints, medicines and cosmetics. Indigo carmine, also known as indigo, is an indigo derivative which is also used as a colorant. In Europe, Isatis tinctoria, commonly known as woad, was used for dyeing fabrics blue, containing the same dyeing compounds as indigo, also referred to as indigo. Indigo is a challenging dye because it is not soluble in water. A more convenient reductive agent is zinc. 499 Wilson Library Corrections? Let us know if you have suggestions to improve this article (requires login). Plants are then covered with clear
Its structure is very similar to that of indigo. The process is easier than the Pfleger method, but the precursors are more expensive. Indigo dye is an organic compound with a distinctive blue color. Speaking of their dire working conditions and the empathy that he felt for them, he wrote: A pre-industrial process for production of indigo white, used in Europe, was to dissolve the indigo in stale urine, which contains ammonia. century BC Mesopotamia that tell about coloring of the wool. Since 2004, freeze-dried indigo, or instant indigo, has become available. Indigo was known all through the old world for its capacity to shade textures a dark blue. Updates? Indoxyl-2-carboxylic acid is generated. The benzene rings in indigo can be modified to give a variety of related dyestuffs. In this method, the indigo has already been reduced, and then freeze-dried into a crystal. Stedman was invited to view the process of making indigo dye at the plantation of the governor of Surinam and he gives the following account of it: These blocks of indigo were what was so highly prized on the European market. A more convenient reductive agent is zinc. The chemical formula of indigo is C16H10N2O2. Indigo was known to the ancients of Asia, Egypt, Greece, Rome, Britain, and Peru. By comparison, the country of Luxembourg is 2,586 km2 (998 sq mi). plantations were African and African-American slaves. Small quantities of indigo were available in Europe then, but they were very expensive due to the long journey required and the taxes imposed by traders along the route. India was a primary supplier of indigo to Europe as early as the Greco-Roman era. In the Spanish colonial era, intensive production of indigo for the world market in the region of modern El Salvador entailed such unhealthy conditions that the local indigenous population, forced to labor in pestilential conditions, was decimated.  Indigo plantations also thrived in the Virgin Islands.  It is also used as a food colorant, and is listed in the United States as FD&C Blue No.  As a major export crop, indigo supported plantation slavery there. The English gained their first indigo-producing colony in this part of the world in 1655 when they captured Jamaica.11 However, it is unclear how important New World indigo was in the worldwide indigo market, as prices fluctuated and so did production numbers. A frequently mentioned example is that of the blue stripes found in the borders of Egyptian linen mummy cloths from around 2400 BC. Romans changed that to indicum.  Many Asian countries, such as India, Japan, and Southeast Asian nations have used indigo as a dye (particularly silk dye) for centuries. After dying, the yarn may be sun dried to deepen the colour. At first the texture is dunked in a vat of dye and kept under the water for a couple of minutes. All rights reserved. About 20 thousand tons are produced annually, again mainly for the production of blue jeans. Some species of such bacteria generate hydrogen as a metabolic product, which convert insoluble indigo into soluble indigo white. Among the Hausa male dyers, working at communal dye pits was the basis of the wealth of the ancient city of Kano, and they can still be seen plying their trade today at the same pits. Two different methods for the direct application of indigo were developed in England in the 18th century and remained in use well into the 19th century. Much European indigo from Asia arrived through ports in Portugal, the Netherlands, and England. In the excavation of Thebes an indigo garment dating from c. 2500 B.C. A frequently mentioned example is that of the blue stripes found in the borders of Egyptian linen mummy cloths from around 2400 BC. Indigo is an ancient dye and there is evidence for the use of indigo from woad or Indigofera from the third millennium BC, and possibly much earlier for woad. The molecule absorbs light in the orange part of the spectrum (λmax = 613 nm). used for dyeing wool and silk. , The synthesis of N-(2-carboxyphenyl)glycine from the easy to obtain aniline provided a new and economically attractive route. Indican readily hydrolyzes to release β-D-glucose and indoxyl. Most indigo dye produced today is synthetic, constituting several thousand tons each year. Mass settles to the
Another example was found on ancient tablets from Mesopotamia in 600 BC that explained a recipe for dyeing wool blue by repeatedly immersing and airing. Privacy statement Indican was obtained from the processing of the plant's leaves, which contain as much as 0.2–0.8% of this compound. Indigo was known all through the old world for its capacity to shade textures a dark blue. The indigo was then reduced in a sequence of baths of iron(II) sulfate, with air-oxidation between each immersion. The Early Modern English word indigo referred to the dye, not to the color (hue) itself, and indigo is not traditionally part of the basic color-naming system. In this process, N-phenylglycine is treated with a molten mixture of sodium hydroxide, potassium hydroxide, and sodamide. Indigo dye is a dark blue crystalline powder that sublimes at 390–392 °C (734–738 °F). There are tablets from 7th
In 1747 the first shipment of indigo left for England, and within two decades more than a million pounds would be shipped each year, making the dye one of the colony’s largest exports, second only to rice. When it first became widely available in Europe in the 16th century, European dyers and printers struggled with indigo because of this distinctive property.  In the May and June 1755 issues of The Gentleman's Magazine there appeared a detailed account of the cultivation of indigo, accompanied by drawings of necessary equipment and a prospective budget for starting such an operation, authored by South Carolina planter Charles Woodmason. We do not tolerate intimidating or disruptive behavior, harassment, or hateful acts. as it the best possible trading commodity, although high value it was compact and long lasting. Natural indigo in India was made like this: cut plant is tied and placed in the vats made of brick lined with cement. When brought out into the air, the shading is a splendid green and gradually it changes to a wonderful profound and rich blue of Indigo.