Furthermore, unlike other textile dying processes, the fabric does not turn blue in the dye pot. Exposure to the air is required, so that a drying piece of dyed fabric will slowly turn from yellow to green, to a deep dark blue. But this process is also very fragile, and skilled artisan is needed to ensure success with indigo dying. Too much fermentation, or not enough, or the wrong level of heat can destroy a whole batch of dye.
For example, in parts of Indonesia, indigo dying is considered a sacred process that only women can take part in. Mothers traditionally teach the dying process to their daughters.
Although interestingly, exceptions have been made for homosexual men. Before the advent of chemical dyes, indigo dying was practiced throughout Europe, most of Africa, the middle East, most of Asia, and South and Central America. The European plant used to create indigo dye- Woad- created a far inferior colour to the plants that grew in the other indigo producing regions. For this reason, trade driven by European colonisation soon destroyed the local European dying industry.
At certain points in the 17th Century, indigo dye mainly from the plant Indigofera Tinctoria was the most valuable import into the Europe. Basically, wherever indigo was traditionally used, the colonising power would look to profit from the booming demand in indigo. In West Africa, indigo textiles were considered so valuable that they were exchanged as currency.
In fact, traditional Asian indigo textiles were shipped to West Africa by the European powers and used to exchange for slaves, who were then shipped on to work on indigo plantations. This plantation dye from the colonies would then be shipped to Europe. The global history of this dyed was thus tied up in the processes of slavery, exploitation, and colonisation. What once was a revered material became a source of misery for countless plantation workers and slaves.
One commentator in , E. Natural indigo dye only declined in prominence once a German chemist Adolf von Baeyer was able to synthesize the colour in Believed to be about 6, years old, this find pushes back the date for the earliest known use of the dye by roughly 1, years, Cynthia Graber reports for Scientific American.
The small cotton scraps were discovered on a excavation of Huaca Prieta, found bundled and embedded in concrete-like layers on a ramp leading up to the temple. They remain in surprisingly good condition despite their age because of this unusual burial at the site. They published their findings this week in the journal Science Advances.
Prior to this discovery, the oldest known dyed fabrics were Egyptian textiles with indigo-dyed bands from the Fifth Dynasty, roughly BC. She and her father had no idea what to grow there, but he sent her seeds from Antigua, and indigo seemed to Eliza to have the most promise. She married a man named Charles Pinkney who wrote down the instructions for how to grow and process indigo, and after a while they made enough seed to hand out to the neighbors, which started an indigo bonanza in the Southern colonies.
Of course, Eliza and Charles Pinkney didn't figure out how to grow and process indigo — their slaves did. The import of African slaves began to ramp up in the southern colonies as a result of the indigo boom in the midth century. In fact, one of the biggest indigo promoters of the time, Moses Lindo , who went to Charleston from England to act as inspector general of indigo coming out of the Port of Charleston, owned a slave ship called the Lindo Packet, with which he imported enslaved people from Barbados to Charleston.
And the indigo fever and the dependence on slave labor that came with it didn't end in South Carolina. Georgia's ban on slavery ended in , and by the beginning of the Revolutionary War 15 years later, the enslaved population of that state had grown to over 18, Though the American colonies winning their independence from Britain tanked the indigo market, it was quickly replaced by rice and cotton.
For its part, England turned its attention to India for its indigo needs, where British colonists forced sharecroppers to grow indigo for hardly any money. The legacy of slavery followed indigo around until it was replaced by synthetic indigo in the early 20th century, when it slipped into obscurity. Indigo is unique in its ability to impart surface color while only partially penetrating fibers.
When yarn died with indigo is untwisted, it can be seen that the inner layers remain uncolored. The dye also fades to give a characteristic wom look and for this reason it is commonly used to color denim.
Originally extracted from plants, today indigo is synthetically produced on an industrial scale. The name indigo comes from the Roman term indicum, which means a product of India. This is somewhat of a misnomer since the plant is grown in many areas of the world, including Asia, Java, Japan, and Central America.
Another ancient term for the dye is nil from which the Arabic term for blue, al-nil, is derived. The English word aniline comes from the same source. The dye can be extracted from several plants, but historically the indigo plant was the most commonly used because it is was more widely available.
It belongs to the legume family and over three hundred species have been identified. Indigo tinctoria and I. Therefore, a large number of plants are required to produce a significant quantity of dye. Indigo plantations were founded in many parts of the world to ensure a controlled supply. Demand for indigo dramatically increased during the industrial revolution, in part due to the popularity of Levi Strauss's blue denim jeans.
The natural extraction process was expensive and could not produce the mass quantities required for the burgeoning garment industry. So chemists began searching for synthetic methods of producing the dye. In Adolf von Baeyer of Baeyer aspirin fame researched indigo's chemical structure. He found that he could treat omega-bromoacetanilide with an alkali a substance that is high in pH to produce oxindole. Later, based on this observation, K. Heumann identified a synthesis pathway to produce indigo.
Within 14 years their work resulted in the first commercial production of the synthetic dye.
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