Research and innovation to recover the ancient art of dyeing ...
The art of dyeing has been part of human knowledge since archaic times. Berries, leaves and spices were used to dye fabrics, but over time natural colors have been replaced by chemical ones that are much cheaper and quicker to obtain but definitely polluting because they are made from petroleum.
Increasing green awareness is now leading to the rediscovery, in an innovative way, of the possibility of dyeing fabrics using plant products without the use of chemicals.
There are many dyeing plants, from which special pigments are extracted that can dye not only fabrics but also hides and hair.
The most valuable dyeing species is ford (Isatis tinctoria). A biennial herbaceous plant of Asian origin belonging to the Brassicaceae or Cruciferae family from whose leaves the blue color is extracted. After the year 1000 in Italy, particularly in the Marches and Piedmont, intensive cultivation developed due to the great demand for this dye, also called "blue gold," which we find in Renaissance velvets as well as in ancient tapestries. In addition to dyeing fabrics," they explain from the Textile Museum in Chieri, "it seems it was also used by some artists, such as Piero della Francesca to Luca della Robbia, in the form of a sky-blue lacquer.
The color gold is obtained from the flowers of Anthemis tinctoria, known as "dyers' chamomile," which are rich in pigments. While for yellow, many different species are used including saffron, safflower and turmeric.
Red is obtained from madder, a herbaceous plant of Eurasian origin that contains the pigment carmine in its roots. Also widely used in antiquity was scotanus (Rhus cotinus), called the "fog tree" from its macerated leaves, bark and branches a very distinctive purple color was extracted.
The nettle plant, known for its medical properties, is among the dyeing species: its leaves give a green tending to gray, while the widespread ivy gives the same color but with bright tones.
Colors are also obtained from some trees, the best known perhaps being the walnut from whose hull brown can be extracted, also suitable for dyeing hair. From Haematoxylum campechianum, a tree of Central American origin, on the other hand, dark tones ranging from black to blue are extracted from the wood, which is chopped, boiled and fermented.
Not only plants and spices, food scraps can also be used to dye fabrics in an environmentally sustainable way.
Dried pomegranate peels, for example, can be used to obtain shades ranging from orange to cool yellow, the variability of the final effect depending on the degree of ripeness of the peels themselves before drying. From avocado peels and seeds, on the other hand, pink is obtained.
The dyeing process is usually done by infusing the dyeing herbs from which the "color bath" is formed.
To extract the blue from the ford, ancient dyers collected the leaves, which were dried, ground and then reduced to a mush that was packaged into buns "the cuccagne," which were easily marketable. To activate the dyeing process, the resulting bricks were soaked in barrels filled with hot water to which a catalyst (ash, rock alum, lime or urine) was added to promote fermentation. The yarns were then immersed in this dye bath and exposed to air and light, so that oxidation would cause the color to be enhanced and fixed.
Green dyeing works on natural fibers such as hemp, cotton, wool, linen and silk while synthetic fibers do not absorb color from natural dyes. Wool and silk are simply dipped in the dye while fabrics such as hemp and linen need an etching process (the garments are boiled in a solution of water and salt or vinegar or bicarbonate) that makes the dye soluble in water, causing it to penetrate the fibers. At this point we proceed with the dye bath by immersing the fabric in the dye bath. The intensity of the result will depend on the time of immersion and the amount of raw material used, but it also depends on the type of fabric, for example wool and hemp do not absorb colors in the same way in the case of dyeing yellow will be brighter in one case and milder in the other.
Several color farming projects are active throughout Italy. Ancient knowledge, experimentation and innovation for a sustainable rediscovery of the ancient art of dyeing, exploiting the coloring properties of plants and herbs. It is chemistry that leads the way in modern natural color production with the evaluation of PH, temperatures, oxygen and soil composition.
The cultivation and processing of dyeing plants, aimed at the production of vegetable color extracts for textiles, fits into the flourishing market of Italian handicraft-textiles, known and appreciated worldwide for the high quality of the products offered. In addition, the cultivation of dyeing plants also allows the exploitation and redevelopment of marginal rural areas, now abandoned, contributing to their socioeconomic survival. A green production with interesting economic implications and that is good for man, avoiding allergies and intolerances produced by chemical colors, and above all for the environment because The natural color is renewable and zero impact.
It 
In