Figure 3: Chemical This can be tested with the Universal Indicator Paper. Modern painting of an It takes about 10-15 minutes for the dye to oxidize. Look out for 'Buy More & Save!' Indigo, unlike many other types of dye, is not water soluble but, it can absorb water. You now have a solution containing, among lots of other things, isatan B, which is an unstable glycoside of indoxyl. There is also an alternative method of making a solution using yeast and sugar. Calculate the percentage yield of indigo as follows: (mass of indigo / mass of leaves) x 100. Image courtesy of Marcel Douwe Dekker; image source: Flickr. 11 months ago. (See our Blog post Preparing an Indigo Dye Vat where we did some indigo dyeing here at George Weil.). The vivid purple of the Pharaoh’s sail was achieved using indigo – a natural dye that can be extracted from certain plants and animals. Naturally derived dyes can contain just one of these pigments or a mixture of two or three in variable proportions, leading to a range of colours from red to blue (Cooksey, 2001). The indigo dyeing process involves making the soluble, yellow-green indigo in the bath turn blue while still attached to the fibre. In a separate jar, dissolve the Soda Ash in some warm water. After applying dye to one side, flip each piece over and repeat the process. Commons. Indigo being extracted from Their entire economy was based on trading Tyrian purple, a violet-purple indigo dye derived from the snail Murex brandaris (now known as Bolinus brandaris). Wet the wool and place in the extract for 10 minutes. furled imperial purple sail. Haha. In this and several other Science in School articles, Gianluca Farusi successfully blends ancient history and chemistry in an unusual mixture – in this case, an innovative and simple practical activity to isolate the dye indigo from the leaves of the woad plant (Isatis tinctoria). Test the liquid by dipping the plastic rod. which it was extracted The pH needs to be between 9-11. Although these two plants contain different precursors, indican in true indigo and isatan B in woad (table 1 and figure 2), they both ultimately yield the same dye – indigo. Please comment if you have suggestions ! In order to make indigo dye, you need leaves from a variety of plant species such as indigo, woad, and polygonum. Orders over £75 are delivered free! Please contact us via our email address editor@scienceinschool.org. brandaris  the secretions Using basic lab equipment, secondary students of all ages could carry out this extraction in one or two practical sessions. I added in about 1 heaping tablespoon at a time and mixed thoroughly before adding the next tablespoon. Because of this, the dye needs to be prepared before the event on the 25th. Empty the contents of the indigo packet into the bucket. Exposing the extract to the air, leading to the oxidation and coupling of two indolin-3-one molecules to form the blue-coloured indigo (figure 3C; dyeing the wool and obtaining indigo powder in the activity below). indigo. learn how we make our indigo fabrics in India in 12-footwells! Calcium hydroxide is used in the reaction to make the stock alkaline. As the reaction starts to happen the bucket will become warm, and if you go too fast the indigo could bubble up and overflow. Please enter your email address. Indigo can be a bit of a tricky herbal powder, especially for first time users. The resultant solution is a yellow-green in colour. Remember to stir the mixture once a day. Commons. Here, in the second photo, you can see how the test strip has turned blue from oxidation. Fill a beaker with woad leaves. Then you would have your own beautiful indigo dye product, also you could make it into any kind of things, such as a bag, pants or a skirt. By browsing this website, you agree to our use of cookies. Learn about its fascinating history and how you can extract it at school. In Europe, the dye was extracted from woad (Isatis tinctoria). You could compare the yield from fresh and dried leaves, or compare it with that of other indigo sources such as Indigofera tinctoria. background of woad from Please login or create an account to be able to subscribe. Question Decided to publish my favorite DIY activity : indigo dye. Filter the extract through ordinary filter paper to obtain the indigo powder. The paste is mixed with ash water, fruit sugars or rice whiskey, and left to ferment. The alkalinity will help to dissolve the indigo. Click on image The Phoenicians perfected this process over hundreds of years and discovered that by varying the species of snail, extraction methods and processing, they could produce a range of colours from red to purple to blue (table 1). Take out the dyed cloth after 10 minutes dyeing. Add a tiny bit of water just enough to wet the indigo and create a paste. Three plant-based dyes were used alone or in combination to produce the ten colours found in the 70 m embroidery: woad (blues and greens), madder (Rubia tinctorum; reds) and weld (Reseda luteola; yellows and dark green). We have put together an interactive DIY and networking event where we will be dyeing scarves with natural indigo using traditional Indian Bandhani techniques. Remember that indigo and many of its precursors are dyes, so take care not to spill them on clothes or skin. polyester cotton, cotton lycra). What are its major uses? For your first indigo bath it helps to work at the higher range but not above pH11 and wash the dyed fabric in vinegar as the final rinse. image source: Flickr. It is possible to use household detergent, but the alkaline residue may affect the final colour or wash fastness. Images courtesy of Gianluca It’s the dye, indigo. A 12th century manuscript of Store the vat in a warm place if possible. In a separate container add 150g of soda ash (sodium carbonate) slowly to about 1/2 litre of water, stirring until it is dissolved. After the dyed cloth has been in the air for about 10 min, another pail of clear water should be used to wash this dyed cloth until there is no color fading any more. Save while you shop. Note that ‘purple’ is not The powdered form is easiest, as the lump indigo must be ground or pounded to reduce it for use. Before dyeing, it is important to check whether the item is ‘Prepared for Dyeing’ (PFD) or requires scouring to remove any grease, oil or starch. Express the amount of indigo obtained by weight and per leaf (count leaves before extracting them). Add the fructose the same way the calcium hydroxide was added - very slowly, spoon by spoon, mixing after each spoonful. I spooned out a little from the top because it is hard to see in the bucket. image source: Flickr. Adding alkali (ammonia) to hydrolyse the molecule, removing the carbohydrate group to leave indolin-3-one or its tautomer, indoxyl (figure 3B; step 7 in the activity below). That's kind of the same idea here. Indigo builds colour, so the more immersion-oxidation cycles, the deeper the colour. Indigo dyed materials are also very wash-fast, since the indigo blue is not water soluble, except in alkali. He is also the regional tutor for the Italian ministerial project ‘Insegnare Scienze Sperimentali’ (‘teaching experimental sciences’). This activity is part of a larger interdisciplinary project, developed together with 14- to 15-year-old students, to explore ancient scientific techniques. This is my first time to write instructables. Made in the 11th century, the Bayeux Tapestry celebrates the Norman conquest of England; a turning point in English history. Tyrian purple: 6,6’-dibromoindigo and related compounds, Teaching science and humanities: an interdisciplinary approach, Monastic ink: linking chemistry and history, Smell like Julius Caesar: recreating ancient perfumes in the laboratory, Bread-making: teaching science in primary school, LeSa21: primary-school science activities, An artistic introduction to anthocyanin inks, The exhibition ship MS Einstein: a floating source of scientific knowledge, Tyrian purple / imperial purple / argaman, Mixture of indigo, mono- and di-bromoindigo. Remove the leaves from the beaker and cut or tear into small pieces. A simple ‘non-contact’ approach (most people use gloves to avoid dyeing themselves) plus normal, good, hygiene is sufficient precautions for the occasional user, Store in clearly labelled containers well away from children, pets and foodstuffs. Boiling the leaves to extract the water-soluble isatan B (figure 3A; steps 1-6 in the activity below). Natural Dyeing with Designer Alice Temperley, Stir sticks with at least one able to reach the bottom of the dye bath, Sink or tub for rinsing with water supply, Mix together 25g indigo dye powder and 15g spectralite in the jar, Gradually add half a cup of warm water to make a paste, Let the paste stand, covered, for 10-20 minutes. The intensity of the colour is also influenced by the way it is processed, such as whether the dyed cloth is dried in the light or shade. Traditional methods of indigo dyeing can be observed today in Africa, Mexico, India and Japan; indigo vats can be found in almost any country in the developing world, as dyers have adapted age-old techniques to their local situations. In this way, the students began in the same pre-scientific state as Pliny and, through laboratory work and discussion, gained modern scientific knowledge on each of the topics.