Plant Dye Information
The indigo we use is called Tinctora grown locally in Rajahsthan.
Indigofera tinctoria, also called true indigo, is a species of plant from the bean family that was one of the original sources of indigo dye. It has been naturalized to tropical and temperate Asia, as well as parts of Africa, but its native habitat is unknown since it has been in cultivation worldwide for many centuries.
True indigo is a shrub one to two meters high. It may be an annual, biennial, or perennial, depending on the climate in which it is grown. It has light green pinnate leaves and sheafs of pink or violet flowers.
Dye is obtained from the processing of the plant's leaves. They are soaked in water and fermented in order to convert the glycoside indican naturally present in the plant to the blue dye indigotin. The precipitate from the fermented leaf solution is mixed with a strong base such as lye.
Indigo does not form a chemical bond with the fabric, as other dyes. Instead it forms a physical bond, bonding molecularly to the fabric when reduced. The reduced state is also necessary because indigo cannot dissolve in water. When the indigo molecules bond to the fabric and it is re-vatted, the indigo forms layers – like bricks. This makes indigo very impervious to sunlight, but indigo will fade with rubbing. Indigo dye is an organic compound with a distinctive blue colour.
Rubia tinctorum, the common madder or dyer's madder, is a herbaceous perennial plant species belonging to the bedstraw and coffee family Rubiaceae.
It has been used since ancient times as a vegetable red dye for leather, wool, cotton and silk. For dye production, the roots are harvested after two years. The outer brown layer gives the common variety of the dye, the lower yellow layer the refined variety. The dye is fixed to the cloth with help of a mordant, most commonly alum. Madder can be fermented for dyeing as well (Fleurs de garance).
The roots contain the acid ruberthyrin. By drying, fermenting or a treatment with acids, this is changed to sugar, alizarin and purpurin, which were first isolated by the French chemist Pierre Jean Robiquet in 1826. Purpurin is normally not coloured, but is red when dissolved in alkaline solutions. Mixed with clay and treated with alum and ammonia, it gives a brilliant red colourant (madder lake).
Lac is the scarlet resinous secretion of a number of species of lac insects, of which the most commonly cultivated is Kerria lacca.
Cultivation begins when a farmer gets a stick (broodlac) that contains eggs ready to hatch and ties it to the tree to be infested. Thousands of lac insects colonize the branches of the host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as sticklac.
Lac is harvested by cutting the tree branches that hold sticklac. If dye is being produced, the insects are kept in the sticklac because the dye colour comes from the insects rather than their resin. They may be killed by exposure to the sun.
The harvested sticklac is crushed and sieved to remove impurities. The sieved material is then repeatedly washed to remove insect parts and other soluble material.
The use of lac dye goes back to ancient times. It was used in ancient India and neighbouring areas as wood finish, skin cosmetic and dye for wool and silk. In China it is a traditional dye for leather goods.
The pomegranate (Punica granatum) is a fruit-bearing deciduous shrub or small tree in the family Lythraceae that grows between 5 and 10 m (16 and 33 ft) tall.
The fruit is spherical, up to 12 cm in diameter and has a tough leathery skin. Inside there are many seeds, each surrounded by a ruby-red fleshy pulp. The flesh can be made into juice and the syrup grenadine, whilst the seeds can be ground and made into a spice called anardana. The leftover rind is not wasted but used as a dye. One tree yields about 1 kilo of dried rind a year.
Rheum nobile, the Noble rhubarb or Sikkim rhubarb, is a giant herbaceous plant native to the Himalaya, from northeastern Afghanistan, east through northern Pakistan and India, Nepal, Sikkim (in India), Bhutan, and Tibet to Myanmar, occurring in the alpine zone at 4000–4800 m altitude.
It is an extraordinary species of rhubarb. At 1–2 m tall, Himalayan Rhubarb towers above all the shrubs and low herbs in its habitat, and it is visible across valleys a mile away.
The leaves can be up to 1 metre in diameter, they are used as a lining material and also to cover and protect fruit in baskets. A bright yellow dye is obtained from the root.
Catchu is an extract of acacia trees used variously as a food additive, astringent, tannin, and dye. It is extracted from several species of Acacia, but especially Senegalia catechu (Acacia catechu), by boiling the wood in water and evaporating the resulting brew.
The catechu mixture is high in natural vegetable tannins (which accounts for its astringent effect), and may be used for the tanning of animal hides. .
Under the name cutch, it is a brown dye used for tanning and dyeing and for preserving fishing nets and sails. Cutch will dye wool, silk, and cotton a yellowish-brown. Cutch gives gray-browns with an iron mordant and olive-browns with a copper mordant.
Calendula officinalis, the pot marigold, is probably native to southern Europe, though its long history of cultivation makes its precise origin unknown, and it may possibly be of garden origin. It is also widely naturalised further north in Europe (as far as southern England) and elsewhere in warm temperate regions of the world.
Flowers were used in ancient Greek, Roman, Middle Eastern, and Indian cultures as a medicinal herb, as well as a dye for fabrics, foods, and cosmetics. Many of these uses persist today.
1 kg of marigold petals dries to 165 gm and can dye 165 gm of fabric which is less than 1 dress.