14 DAY TRIAL // We all know that the colors impact the human mood. No wonder that along the history, people gave textiles a color by dyeing them. And the search has been always for more resistant pigments, so that the color of our clothes will not fade in time.
Till the middle of the 19th century, colorants employed for dyeing the fabrics were natural, being extracted from plants, insects or mollusks. From woad (Isatis tinctoria) a blue colorant was obtained, while from wild mignonette (Reseda lutea) an yellow colorant was obtained. From madder (Rubia tinctorum) and from the Mexican logwood tree (Haematoxylum campechianum) was extracted a red pigment. From a sea snail (Murex brandaris) was extracted the Tyrian purple also called imperial purple as the clothing of the Roman emperors were dyed with this material. Natural crimson was achieved from the females of kermes (Kermes ilicis), a scale insect, used even during Biblical times by Jews.
But dyeing does not mean just sinking the textiles into a colorant. One stage involves the use of a mordant, a substance with the help of which the colorant fixes onto the fibers, becoming insoluble. Even if many chemicals can be used as mordants, a great part are toxic.
During the dyeing process, unpleasant smells can result, like during the long and complicated process for achieving Turkey Read, when we want to color cotton. The cotton turned glossy red, resistant to sunlight, washing, and bleaching substances. The whole process consisted in 38 stages and took 4 months.
The first synthetic colorant was achieved by William Henry Perkin in 1856, and was a vivid violet. By the end of the 19th century, tens of new synthetic colorants were known and today their number has raised to about 8,000. The only natural sources still used today are kermes and logwood.
Viscose, an artificial silk, was discovered in 1905, resembles chemically the cotton so that it could be dyed with all known colorants at that time.
But other synthetic textiles (like artificial silk from cellulose acetate, polyester, nylon and acrylic fibers) required new colorants.
It is hard to achieve long lasting colors: many fade after exposure to sunlight or washing with detergents, colors on our T-shirts and blouses wash out because we sweat; other fabrics change hue when washed with clothes of different colours.