Natural dye history

The earliest dyes by Kris Driessen The ability of natural dyes to color textiles has been known since ancient times. The earliest written record of the use of natural dyes was found in China dated 2600BC. Chemical tests of red fabrics found in the tomb of King Tutankhamen in Egypt show the presence of alizarin, a pigment extracted from madder. In more modern times, Alexander the Great mentions having found purple robes dating to 541BC in the royal treasury when he conquered Susa, the Persian capital. Kermes (from the Kermes insect) is identified in the bible book of Exodus, where references are made to scarlet colored linen. By the 4th century AD, dyes such as woad, madder, weld, Brazilwood, and indigo and a dark reddish-purple were known. Brazil was named for the wood found there. Purple was made from a mollusk and clothing made from it was so expensive only the royal family could afford it. It was extracted from a small gastropod mollusk found in all seas or from a crustacean called a Trumpet Shell or Purple Fish, found near Tyre on the Mediterranean coast. Their body secreted a deep purple fluid which was harvested by cracking the shell and digging out a vein located near the shellfish head with a small pointed utensil. The mucus-like contents of the veins were then mixed together and spread on silk or linen. Estimates are that it took 8,500 shellfish to produce one gram of the dye, hence the fact this dye was worth more than its weight in gold. This expensive dye was also mentioned in the bible, in Acts, where Lydia is a seller of purple. By the 15th century, dyes from insects, such as cochineal and Kermes, were becoming more common. By the 17th century, dyeing cloth "in the wood" was introduced in England: logwood, fustic, etc. In the 18th century a method of bleaching linen with kelp was introduced in Scotland, a Swedish chemist discovered chlorine destroys vegetable colors and the French began to recommend chlorine water for commercial bleaching. Indigo began to be grown in England, and Cudbear, a natural dye prepared from a variety of lichens, is patented. Another natural dye, Quercitron, from the inner bark of the North American oak, is patented in 1775. See The Red Dyes : Cochineal, Madder, and Murex Purple : A World Tour of Textile Techniques By the 1800's, Prussian Blue and Sulphuric acid are available commercially. Prussian blue was formed from prussite of potash and iron salt, making it one of the earliest known chemical dyes. In 1856, William Henry Perkin, while experimenting with coal tar in hopes of finding an artificial quinine as a cure for malaria, discovered the first synthetic dye stuff which he called "Mauve". The color quickly became a favorite of the royal family, and a new industry was begun. See Mauve: How One Man Invented a Color That Changed the World

Types of Natural Dyes Natural dyes can be sorted into three categories: natural dyes obtained from plants (indigo), those obtained from animals (cochineal), and those obtained from minerals (ocher). Although some fabrics such as silk and wool can be colored simply by being dipped in the dye, others such as cotton, require a mordant. A mordant is an element which aids the chemical reaction that takes place between the dye and the fiber so that the dye is absorbed. Containers used for dying must be non-reactive (enamel, stainless steel.) Brass, copper or iron pots will do their own mordanting. Not all dyes need mordants to help them adhere to fabric. If they need no mordants, such as lichens and walnut hulls, they are called substantive dyes. If they do need a mordant, they are called adjective dyes. Common mordants are: ALUM, usually used with cream of tartar, which helps evenness and brightens slightly; IRON (or copperas) which saddens or darken colors, bringing out green shades; TIN, usually used with cream of tartar, which blooms or brightens colors, especially reds, oranges and yellows; BLUE VITRIOL which saddens colors and brings out greens and TANNIC ACID used for tans and browns.

Natural dyes obtained from plants One example of a natural dye obtained from plants is madder, which is obtained from the roots of the madder plant. The plants are dug up, the roots washed and dried and ground into powder. During the 19th century, the most widely available fabrics were those which had been dyed with madder. The 'turkey red’ that was so popular at that time, was based on madder. This red was considered brilliant and exotic. The madder plant continued to be used for dyeing until the mid-1800s when a synthetic substitute was developed. Another example of a natural dye obtained from plants is woad. Until the Middle Ages, Europeans used woad to create a blue fabric dye. The woad was a shrub that grew abundantly in parts of Europe. The coloring was in the leaves, which were dried and ground, mixed with water and made into a paste. This dye was supplanted by indigo, an ancient shrub well known to the Egyptians and Indians. Like woad, its color lay in its leaflets and branches. The leaves were fermented, the sediment purified, and the remaining substance was pressed into cakes. Indigo prevailed as the preferred blue dye for a number of reasons. It is a substantive dye, needing no mordant, yet the color achieved is extremely fast to washing and to light. The manufacture of natural indigo lasted well into the early 1900s. In 1905 Adolf von Baeyer (the scientist who also formulated aspirin) was awarded the Nobel Prize for discovering the molecular structure of indigo, and developing a process to produce it synthetically. The natural dye was quickly replaced by the new synthetic, ending an ancient and honored botanical history.

Natural dyes obtained from minerals Ocher is a dye obtained from an impure earthy ore of iron or a ferruginous clay, usually red (hematite) or yellow (limonite). In addition to being the principal ore of iron, hematite is a constituent of a number of abrasives and pigments. Natural dyes obtained from animals A good example is cochineal, which is a brilliant red dye produced from insects living on cactus plants. The properties of the cochineal bug was discovered by pre-Columbian Indians who would dry the females in the sun, and then ground the dried bodies to produce a rich, rich red powder. When mixed with water, the powder produced a deep, vibrant red coloring. Cochineal is still harvested today on the Canary Islands. In fact, most cherries today are given their bright red appearance through the artificial color "carmine", which comes from the cochineal insect.