Indigo is used so beautifully in traditional textiles. But once I started delving into the history of indigo for the purposes of writing this article I discovered that there is so much more than meets the eye. There are early archaeological finds from over years ago in Egypt, India and China.
But it is believed that the history of indigo stems back as early as the Neolithic age. Although blue occurs in many instances in the plant world, commonly in flowers and berries, most naturally occurring blue plants-stuffs are unsuitable for dying. Some can be used to derive some colour for food or textiles but the blue colour is not long-lasting.
Indigo, on the other-hand, is the only natural source of long-lasting blue colour for textiles. However, indigo the colour does not occur in nature. The plants from which we derive indigo do not show any blue in their leaves, stems or flowers. Rather the colour indigo is achieved by fermenting the leaves of certain plant varieties to create indigo dye.
You can also check this video to see how one farm in India creates natural indigo dye in a traditional way. It involves very precise chemical processes to ferment the leaves of indigo plants to create the blue dye.
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.
The fabric is wrapped around a pole and then bound. The cloth can be wrapped diagonally, or not, depending on which direction you want your lines to go. In fact, a lot of people find perfection in the imperfection created with this technique. Wrapping dry fabric around the pole will result in air pockets where the indigo will not adhere to the fabric.
This will give a more mottled effect, which can be quite spectacular. I, however, usually wet my fabric before wrapping. If you wet it, make sure you wring it out thoroughly before proceeding to the next step. Start wrapping your fabric around the pipe or pole, making sure to have the fabric as flat as possible against the surface of that you are wrapping it around. This will make sure the fabric stays in place. Secure your string around the top of your fabric and string wrapping it around your fabric.
Each wrap of the string will create a stripe where the dye will not permeate as fully and can be as precise or loose as you like. Make sure that if you want the entirety of the fabric dyed, that the resultant scrunch can be fully submerged into your dye bath!
Take off the lid of your dye bath and place the pipe into it so that the fabric is fully submerged into the dye. Do this slowly and carefully without too much movement to avoid introducing oxygen into your dye. Once your fabric has been in the dye solution for the allotted time, remove the pipe and fabric from the dye bath with as much care as you used putting in there.
Remove the thread by untying or cutting it off. Try to wear gloves as the dye solution can be irritating to the skin. Remove the fabric from the pipe and make sure any excess dye has dripped off.
Hang it up to dry for a further 10 minutes. When the water in one bucket runs blue, continue rinsing in the second bucket. You might also want to rinse it in your final bucket with a little bit of vinegar to really get any excess dye off. This will minimise any crocking onto light coloured clothing!
While dyeing with indigo does require a fair amount of preparation and care, the results you can achieve by playing with shibori techniques can be quite spectacular! I often choose to use viscose, as opposed to cotton, as it remains soft after dyeing, making it ideal for a scarf or something similar.
Viscose, like cotton or linen, is a fabric made from natural cellulose fibres and as such, takes the indigo dye quite well. Cotton can be used to more hard-wearing items like pillow cases or bags, but you can also use wool and synthetic fibres. Some people might avoid using synthetics as the indigo can have trouble binding to these fabrics: they tend to have a tighter weave so the indigo molecules have less chance of getting lodged between the fibres.
However, dyeing synthetic fabrics is not impossible and can give interesting results. Part of the fun and charm of dyeing with indigo is in the experimentation! Denimhunters is a knowledge portal for denim enthusiasts and newcomers. Start your hunt here! Felix Pecarski is a denim enthusiast from London who now calls Stockholm home. Save my name, email, and website in this browser for the next time I comment.
In this process the plant is mixed with wheat husk powder, limestone powder, lye ash, and sake. The mixture is allowed to ferment for about one week to form the dye pigment which is called sukumo. The chemical symbol for indican, the compound found in the leaves of the indigo plant that is used to make indigo dye.
During indigo manufacture, the reaction process is continuously monitored to ensure the chemicals are combined in the proper ratios. If any of these variables deviate from specifications, the resulting reaction product can be affected.
Typically, poor quality control results in lower yield of the dye, which increases costs for the manufacturer. To ensure that manufacturers can consistently purchase the same shade of dye, indigo is assigned a Color Index number that defines its shade. Indigo production produces a variety of waste products which must be handled carefully.
In addition to the reactants described above, there are other reaction side products that are produced along with the indigo. Some of these materials are considered to be hazardous and must be disposed of in accordance with local and federal chemical waste disposal guidelines. These waste chemicals can enter the environment in at least three different ways. The first is during the actual manufacture of the molecule.
The second is when the dye is applied to the yarn, and the third is when the dye is eluted into the wash water during the initial stonewashing or wet processing of the fabric. This last route typically occurs during the production of denim fabric. Much of the need for indigo is being met with other types of blue dyes and today most of the indigo used by the world is made out-side the United States.
Researchers are concentrating on new methods of indigo manufacture that are more environmentally friendly.
One promising future method involves using biocatalysts in the dye reaction process. Indigo dye may be one of the first high-volume chemicals made through a biological route. Genencor International, of Rochester New York, is evaluating a process to produce indigo using biotechnology. According to Charles T. However, at this time the technology is expensive and production costs could be prohibitive.
Genencor is seeking a major market partner to work with them in the development of this new technology. Manufacturers who use indigo in dying operations are also seeking to improve their use of the dye. Compared to traditional methods of stonewashing fabric dyed with indigo, their new process uses few, if any, pumice stones which help give the fabric its faded look. Therefore, pumice stone handling and storage costs are reduced, along with time required to separate pumice from garments after stonewashing.
It also uses much less bleach. Therefore, this new process not only reduces garment damage, but also reduces waste produced by the stones and bleach. Kirk, R. Othmer ed.
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