THE ARTof dyeing

Choose a colour and find out its semantics

SEMANTICS OF THE COLOUR RED

The relationship between man and colour has a long history, dating back to when people first learned how to obtain and use natural dyes. The original sacredness of colour was lost as human society evolved, and in medieval Europe, the main interpretations of colour symbolism were laid down in the depths of the Christian religion and its dogmas. Christianity finds the meaning of each colour in the Bible. White, black and red predominate in the Holy Scriptures in terms of meaning and frequency of references. Red is ambivalent. Dark red meant love, and scarlet has become a symbol of martyrdom, the sacrifice made, it is the colour of the blood of Christ, shed for the salvation of people, the embodiment of divine love and the Holy Spirit. At the same time red was the colour of hell and of the devil. The union of blue and red gives purple, which is the symbol of the union of the heavenly and earthly beginnings.

The religious symbolism of colour was the basis for artistic symbolism, which has an impact on man's emotional and aesthetic perception. It was reflected not only in paintings, but also in the subjects and colour schemes of woven artworks, and hence in the dyeing industry. The colour palette of clothes gradually acquired distinct social features. The same colour in different cultures and even at different stages of the development of one culture received different, sometimes directly opposite meanings. Thus fabrics and clothes are the most responsive to such changes in material culture.

The colour red is contradictory. In the history of mankind, it could symbolise love, beauty, greatness, power, joy, wealth and vitality, while nothing prevented it from being associated with war and bloodshed, revenge, hostility, aggression, fury and hellfire. As many studies have shown, the psychophysiological associative perception of colour has a paramount influence on its symbolic meaning. Psychologists have claimed that red is an excitatory, active colour that enhances nervous and hormonal activity.

During the Renaissance in Europe, bright scarlet and blood-red hues were used less frequently. They were replaced by a variety of tones: pink, purple, burgundy and crimson. Gradually, the red colour lost its meaning under the pressure of morality. In 16-17th centuries it was no longer in fashion to show luxury, and from the economic point of view it was impractical to spend huge amounts of money on purple fabrics. Red began to be associated with immorality, pride, lust, debauchery and sin. In different countries regulations were issued, peculiar rules for wearing certain colours depending on one's social status, professional activity and even physical state. Red in its pure form became the basic colour for cardinals, and also for people whose professions were marked with blood (executioners and butchers), for adherents of other religions (Muslims and Jews), those who stepped on the path of vice (prostitutes). Outcasts of society, who became such for various reasons, such as leprosy and syphilis patients, people with mental illnesses and mental disorders, people suffering from alcoholism were also to be dressed in red.

At the beginning of the 16th century, as a result of the Reformation (an anti-Catholic movement), Protestantism, one of the three trends in Christianity, which is a set of independent churches and unions, became widespread in most European countries. During religious twists and turns, the colour gradually lost its mystical associations, the colour symbolism became mundane and the attitude to colour became more practical. At the same time, the multi-faceted colourism of the Catholic Church was countered by the colour austerity of Protestantism. The passionate struggle of Protestants for morality, aversion to luxury, disdain for pleasure and inclination to abstinence were not only reflected in the style of clothing, but also played a major role in the spread of the new colour scheme: red, as well as most of the bright saturated colours, had no place in the decoration of the church. Protestant clothes gradually lost not only the red colour and its shades (pink, purple, orange), but also other colours. Soon dark blues, blacks, greys and browns dominated in the colouring of fabrics.

The commitment of artists to religion was great: the palette of masters from Protestant Europe at this period differed from the colour scheme of Catholic artists. All this was reflected in the colouring of fabrics. If natural tones (blue, green, beige, brown) were approved by the leaders of the Protestant movement, then red remained forbidden. In contrast to Protestant painters Catholic painters widely used all shades of red (just think of the masters of the Italian Renaissance). Florence and Venice were characterised by the use of lush purple draperies both in home decorations, works of art and clothing. In Spain, where Protestant communities were almost completely destroyed by the Inquisition, there was also a riot of colour in clothing: red caftans and scarlet dresses often made an appearance in the streets of Spain in the sixteenth century.

Catholicism, in an attempt to restore the position and prestige of the Roman Catholic Church, would defend the multicoloured decoration of the temple and religious garments. In doing so it allowed Protestantism to gain the upper hand in everyday life. It is important to note that among Catholic commoners red remained the colour of celebration, beauty, so festive clothing, and even wedding clothes, were almost always dyed red. This was most likely due to the cheapness of red fabric in that period of time. A century later red would lose its position completely in everyday life, but it would retain a dominant position in symbolism. A variety of local natural red dyes (madder, kermes, purple, daubings) as well as those brought from the East and the newly discovered countries of the New World (chenille, pterocarpus, types of "Brazilian trees"), the development of the dye industry in general, allowed the creation of a huge number of persistent shades of red (mauve, maroon, crimson, coral, carmine). They were not vetoed as bright red in its purest form. The rejection of red in everyday life did not affect the semantics of natural objects. Red flowers and fruits - apples, tomatoes and pomegranates - were firmly associated with beauty, love and glory.

European colour symbolism in the 15th-17th centuries was formed not only under the influence of theology. Scientists, artists and philosophers contributed greatly to its development. At the end of the seventeenth century, the symbolism of colour in Western Europe was almost devoid of its religious content. Thus the theological stage of colour symbolism may be considered completed. However, it should be remembered that colour, like no other symbol in culture, is a great governing tool due to the universality of its meanings.

SEMANTICS OF THE COLOUR BLUE

The history of any colour, its meaning and symbolism cannot be considered in isolation from the political, religious and cultural aspects of history. In Western Europe, an epidemic of bubonic plague broke out in the mid-14th century, claiming the lives of millions of people and placing a heavy economic burden on the survivors. At the end of the epidemic most European countries began to issue laws against luxury. The moralisation of society was aimed at maintaining and strengthening the Church's traditions, the true virtues. Economic necessity forced a reduction in excessive spending on clothing, household items, jewellery and works of art. The segregation of society according to rank, origin, sex, profession and even physical condition intensified. In the sixteenth century the Reformation (anti-Catholic movement) led to the emergence of a new trend in Christianity, Protestantism, which was a set of independent churches and unions. The Reformation increased the power of the governing laws and regulations, which existed in Europe until the 18th century and were reflected, among other things, in the use of a colour palette in the dyeing of fabrics and clothing, and in painting.

The supporters of the Reformation, who perceived colour as a source of falsehood, luxury and illusory deceit, banished it from the temple. Only a few selected, 'righteous', 'high moral' colours remained: white, grey, black and blue. Catholicism, which believed that there should be plenty of luxury and colour in God's house, actively opposed Protestant asceticism. Heavenly blue was allowed into the colour palette of Protestant artists, along with brown, green and other natural colours. Often one can see the influence of Protestantism in the work of Catholic painters: the muted colours, the play with light in a monochrome palette. But still the predominance of blue in the works of European masters of the sixteenth and seventeenth centuries largely depended on the artist's preferences, skill and taste. Suffice it to recall the bright, juicy, piercing tones of blue in the works of Vermeer, Raphael and Titian. During the Renaissance blue became a favourite colour of painters. Its meaning is always positive and stable. Blue was made from azurite and the more expensive lapis lazuli.

During the Reformation era, the colours of clothes were the most affected. Clothes originally associated with original sin, according to the leaders of the Protestant movement, had to be simple, plain and comfortable for work and everyday life. But there was also a place for blue. It became dark, muted, but not banned.

Unlike most colours, blue has no ambivalence at all. Blue is the colour of kings, the colour of the Virgin Mary and angels, the colour of morals, spiritual and bodily purity, eternity and peace. In a religious context, blue corresponds to the Holy Spirit, the colour of divine grace. Contemplation of the divine blue was supposed to promote godliness, the pursuit of meekness, humility and righteousness. The colour blue was associated with eternal truth and the inscrutability of divine mysteries even at the dawn of Christianity. Blue is an indispensable colour in iconography. According to the canons, Jesus was depicted wearing a red chiton with a blue hymation (outer cloak). Our Lady, on the contrary, was dressed in a blue tunic with a red veil. Red and blue are again the antagonists: they denote earth and heaven. The union of these colours results in purple, the symbol of the unity of the earthly and the heavenly.

As the eternal antagonist and rival of the red, the blue from the sixteenth century came to the fore. The "sinfulness" of red, its luxury, and its conspicuousness made scarlet an outcast. The triumph of the blue left it without a worthy opponent. It was a five-century-long road to glory: blue was recognized by theologians, then appreciated by artists, the dyers were able to make it bright and accessible to the masses, it was not repulsed by the Reformation, and the Enlightenment era made blue a symbol of progress and freedom.

Blue owes such extraordinary development and stability in culture and everyday life not only to theology and politics. Natural dyes played a big role. During antiquity and the Middle Ages, the blue dye was produced mainly from vaida and highland dye, plants which grew extensively all over Europe. Indigo, a dye derived from the Indian plant indigofera, was also known in ancient Rome and Greece, but blue was rarely used in dyeing fabrics, being considered a barbarian colour. From the thirteenth century onwards, indigo began to flood Europe, but it was expensive and often embargoed economically or military conflicts prevented its importation from the East. It was not until the early 18th century that indigo exports increased and fully covered the needs of Europeans. In the sixteenth century, logwood, a new source of blue dye, began to be imported from the New World.

Research by psychologists and physiologists suggests that blue, while a serious, monumental colour, is soothing and relaxing. It is one of the most mystical and transcendent colours. But constant exposure to it can lead to depression, low spirits and apathy. Sky blue, on the other hand, is the colour of freshness, invigorating and relaxing.

SEMANTICS OF THE COLOUR YELLOW

Colour for humans is not just a subjective physiological visual sensation, but also a social phenomenon. It is society that gives colour symbolism and meaning, and regulates it. In all ancient cultures, yellow was a sacred colour. It is the colour of the sun, gold, generosity, intelligence, a sign of light, warmth and prosperity. But in medieval Europe, attitudes towards it became ambivalent. The symbolism of yellow was conflated with gold and identified with light, grandeur, joie de vivre, health, because gold is incorruptible and not subject to ageing. On the one hand, warm yellow was reminiscent of honey and the colour of ripe wheat, associated with pleasure and abundance. On the other hand, yellow is the colour of deceit, duplicity and mistrust. These associations have their origins in the humoral theory formulated by the Greek physician Hippocrates around 400 B.C. and developed in the Middle Ages. According to this theory, four fluids (blood, phlegm, black bile and yellow bile) were believed to flow in the human body. The predominance of one of the fluids determines the temperament of man. Thus, yellow bile prevails in the body of choleric, which is characterized by impulsiveness, lack of balance, tendency to sudden mood swings, violent emotional outbursts. The yellowish tinge of the face of someone suffering from a serious illness was a negative association.

Negative connotations of the shades of yellow is different: light yellow meant betrayal and carnal desires; dim yellow was associated with jealousy and adultery; ochre yellow - the colour of fear and terror; gray-yellow - madness; greenish yellow symbolized the demonic. The combination of yellow and green was aggressive and disturbing, associated with damage to the mind, madness, and prevailed in the clothing of jesters, the insane. Only the colour gold retained the symbolism of "proper yellow". The devaluation of yellow, which began in the thirteenth century, a century later led to the fact that this colour was perceived as the colour of deceit, deceit, hypocrisy and treachery.

Yellow was the colour of the clothes of those cast out on the margins of life: executioners, counterfeiters, street prostitutes, who wore yellow dresses to make them easier to spot at night in the dim lights of lanterns. Yellow became the colour of the Jewish communities: all Jews had to wear yellow clothing or bright yellow markings on their dress in the form of a circle, ring, star or headband by specific regulations.

The golden yellow colour in the clerical garments symbolised divine light, royalty, glory and dignity. In religion, gold embodied eternity, imperishability and immortality, and was also associated with the light of Tabor (according to New Testament texts, this is the mysterious divine light that appears at the moment of the Transfiguration of Jesus Christ). In iconography, yellow signifies warmth and joy, love and harmony. In the icons and paintings the clothes of the traitors Apostle Judas and the fallen angel Lucifer are painted in yellow-green tones or a combination of these.

The Reformation (a religious, socio-political and ideological movement in Western Europe aimed at transforming the Roman Catholic Church) that began in the 16th century led to the emergence of Protestantism. Protestants, who advocated the banishment of bright colours not only from temples, but also from everyday life of their adherents, recognised yellow as a vice colour and completely rejected it in everyday life and art. The paintings of Protestant painters were saturated with dark tones: only muted natural shades of yellow were shown. During the Reformation, yellow tones were also forbidden in clothing.

When in the 15th century icons were replaced by paintings, religiosity was preserved in the subject but lost its spiritual significance. In classical Renaissance paintings, artists rarely used yellow in its purest form. It was out of the colouristic context of the painting by its brightness and contrast. Renaissance paintings were dominated by yellow-brown, ochre, straw and sandy shades of yellow. In the seventeenth century, in the Baroque era, golden yellow returned in all its glory, but in clothing even in the eighteenth century yellow continued to be associated with hostility and aggression.

In Europe there was a huge number of wild plants, from which in the 15th and 17th centuries inexpensive natural yellow dyes were obtained: yellowing reed, dyer’s greenweed, foxglove, smoke tree, sumac. With their help, one could achieve permanent dyeing of fabrics and leather in yellow, yellow-orange and brown tones. The use of different mordants allowed a variety of palettes.

Sometimes even today yellow, bearing the imprint of a symbolic past, is an understated and ambiguous colour for clothing. Neurophysiologists consider yellow to be a stimulating, active colour. It encourages intense activity, communication and positive emotions, but prolonged exposure to yellow can lead to over-excitation and then inhibition of the nervous system.

Choose a colour and find out its semantics

Mexican logwood

Haematoxylum brasiletto H. Karst

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Mexican logwood is the name of several different species of trees from which red dye is obtained. Since the 12th century, Arabs supplied Europe with wood of Caesalpina sappan L., common in the East Indies (primarily in Malaysia). It was used for making paints as well as furniture and musical instruments. When the Portuguese discovered Caesalpinia echinata Lam. in Brazil at the beginning of the 16th century, they thought they had found where the so-called "palo de brasil"(from the Portuguese word brasa for "heat," "hot coals") sold by Arab traders. The territory that was first designated on maps as the Land of the True Cross soon became known as Brazil. These plants belong to the same genus and are very similar in appearance. At the end of the 15th century, the Spanish began to import the wood of Haematoxylum brasiletto H. Karst., which also resembles the wood of the cesalpinia described above. Because of this resemblance and similar dyeing properties of the wood, some confusion occurred. Thus, all those trees are often called Brazilian.

Area

Biological description

The Mexican logwood (Haematoxylum brasiletto H. Karst.) is a shrub or tree up to 8 meters tall in the legume family. The core of the trunk is dark red in colour. The trunk is wrinkled and covered with thorns. The parted leaves fall off during the dry season. The flowers are yellow, clustered in globular inflorescences. The fruit is a bean.

Chemical Transformations

The core of the tree contains brazilin (a neoflavonoid), which can be extracted from the wood with hot water. With air oxygen or other mild oxidants it is easily oxidised to brazilein. The wood is ground and boiled for three hours in a large volume of water. The broth is then left to mature for about a day to a month. Silk and wool are pretreated in alum (using salts of aluminium, tin, chromic acid or a mixture of these) and then dyed. The colour depends on the acidity of the mixture and the fixative used. Aluminium mordants in combination with brazilin will produce standard red colours while tin mordants will result in pink colour. Dyeing is done in an acidic environment.

History

Mexican logwood has been exported to Europe since 1497 for dyeing purposes. The dye was used to dye cloth and wool a dark red colour. The dye was resistant to washing, but easily faded in the sun. In the 16th century, Venetian dyers used it to darken the red dye obtained from madder. Trade in the wood continued apace until the early 20th century. The red dye is now exported mainly to South American countries.

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The broth from the wood chips is used by the locals as an astringent, for fever, jaundice, inflammation and stomach aches.

Kermes vermilio

Kermes

Photo: Spodek M, Ben-Dov Y

Kermes is a genus of small insects of the Homoptera suborder Coccidae (worms and scaleworms). Dried insects of this genus were used to produce kermes dye with bright carmine or scarlet colour. The genus includes more than 60 species in the northern hemisphere. All insects are monophagous, i.e. very specialized in feeding. They are pests for certain plant species: oaks, chestnut trees, castanopsis, lithocarpus, chrysolepis. Almost all species can be used to produce dyes, but the most popular, used on an industrial scale, was the Mediterranean kermes (Kermes vermilio).

Area

Biological description

The Mediterranean Kermes (Kermes vermilio (Planchon, 1864)), or oak chenille, lives only on the oak, or Quercus coccifera L. The female insect is spherical, no more than 8 mm in diameter, dark red in colour, covered with a very fine white powdery plaque. They have short, pointed protrusions along the edge of the body. Females are immobile and have no antennae, legs or eyes. Males are up to 3 mm in diameter, dark crimson in colour, with threadlike antennae, equipped with a pair of well-developed wings and are mobile.

Two generations of insects may emerge during the year, in late spring and September. After emerging from the eggs, the wandering larvae (first-stage larvae) spread themselves on oak branches in search of food. Often the larvae are carried by the wind to neighbouring trees. The larvae then use their proboscis to attach in cracks in the bark, at the base of the buds, where they remain motionless. They are difficult to spot among the branches. In winter, the females develop into second-stage larvae, which can easily be distinguished by the conical pointed protrusions on their backs. In spring, when sap begins to move in the tree, the females actively feed and grow. The males, after feeding, enclose themselves in tiny white waxy cocoons, attaching themselves to the back of oak leaves or to leaf litter. By the end of April females reach the size of adults and males emerge from their cocoons, where their bodies undergo a restructuring (mouthparts are lost, but wings are formed). They hover briefly in search of mates, and die immediately after mating. After mating, the females lay more than 6,000 eggs in the incubation chamber. The females die and their dried-out calves, attached to a tree, serve as a brood chamber for the eggs. At the end of May, the larvae hatch from the eggs. It is not uncommon for them to produce a new generation of insects as early as the autumn of the current year. Females can reproduce by parthenogenesis, i.e. they lay eggs without fertilization.

Chemical Transformations

The bodies of female kermes contain kermes acid, which belongs to the group of anthraquinone dyes. Whether the females were still alive or dead but before larvae emerged from their eggs, they were harvested by hand, by scraping them off with fingernails. This work was done by women and children who could collect about 1 kg of raw material in a day. The figures are surprising: to get 50 grams of dye, 5 kg of insects had to be gathered. Taking into account their size and sharp tips on the leaves of Hermes oak, the labour was truly Herculean.

After collecting the insects, they were dried in the sun. Often the bodies of the females were separated from the eggs before drying. The dye obtained from eggs and insect pulp was 4 times more expensive than the one obtained from the female body shells. The separated eggs were dried for 3-4 days under the sun, while the eggs were dipped into vinegar and then dried as well. Often fermented bran broth was added to the colouring solution. The cloth was dipped into the boiling solution for one hour. Dyeing was preceded by soaking the cloth in alum and white tartrate (crystalline residue that precipitates during the alcoholic fermentation of wine).

Kermesic acid was first isolated in its pure form only at the end of the 19th century by Heise, and its structure was described by the German chemist Otto Dimroth at the beginning of the 20th century. The same researchers identified eight other red and yellow-orange dyes from the bodies of insects, but their study is still in progress.

History

Since ancient times, kermes has been widely used in the Mediterranean region. The philosophers and scientists of Ancient Greece (Theophrastus, Pausanias, Dioscorides) and Ancient Rome (Pliny the Elder) paid attention to kermes dye. The blood red colour of kermes was identified with animal blood. It was widely used in Central and Western Europe. Kermes was a valuable commodity, transported along the Great Silk Road in the opposite direction (from Europe to the East). Its use on Oriental fabrics is well known as early as the 3rd century B.C.

In the Book of Isaiah the prophet contrasts the skill of dyeing kermes red with the purity of undyed wool: "Though your sins are like scarlet, they shall be as white as snow; though they are red as crimson, they shall be like wool." (Isaiah 1: 18).

The flowering of kermes as a dye came in the Middle Ages. For a long time, kermes was the source of Europe's most expensive dye, known in the Middle Ages as écarlate. It gave fabric a brilliant rich red colour and was a symbol of power and wealth. The colour resulting from dyeing with pure kermes was called "vermel". The combination of red dye (écarlate ) and blue pastel gave pink, scarlet, bloody, grey and brown-black hues. As purple dyes had all but disappeared in the West by then, vermilion became the most prestigious paint of kings and nobles. In Spain, the Arab conquerors continued, as did the Romans, to tax the local population for kermes.

It is interesting to know that in Florence in the middle of the 14th century, dyeing one piece of fabric with écarlate cost 35-40 florins, while dyeing it in turquoise would only cost 17-20. To cut the price, unscrupulous dyers added madder to kermes dyes. Such a combination resulted in permanent, but dim coloring. For instance, in the 13th century, a dyer could be fined for it with his right hand (it would be chopped off).

In 1464, after the fall of Constantinople, where the last workshops for purple dyes remained, Pope Paul II decided to replace purple with vermilion for cardinals' vestments. It was a great victory for écarlate over purple. But the triumph was short-lived. In 30 years, shortly after the discovery of the New World, a different kind of red dye - cochenille - was flooding into Europe. Only a few workshops in Europe and Asia preserved the traditional dyeing with kermes until the 19th century.

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In ancient Greece, Ancient Rome and Persia, doctors widely used kermes powder to heal wounds, treat eye diseases, heart ailments and as a strengthening agent. The tradition of treating with kermes continued until the early 19th century.

The famous Swedish naturalist Carl Linnaeus, who was unable to visit kermes dye shops in the Mediterranean, mistook the Mediterranean kermes (Kermes vermilio) for the more common European species of oak worm (Kermes ilicis), which lives on stone oak (Quercus ilex), but this species gives a beige-brown colour and contains no red.

Cochinea

Dactylopius coccus Costa

Protasov AN/Shutterstock.com

Cochinea was used as a pigment for art paint and as a beauty product. It was already used by the ancient Maya and Aztecs as an ointment for wounds, for headaches and heartaches. Nowadays, cochinea is the only dye of animal origin that is approved for use in the food industry.is a collective name for several species of insects in the Homoptera suborder Coccidae (worms and scabworms). Female insects are used to produce carmine, a red dye. In ancient times, carmine was obtained from Porphyrophora polonica L., Porphyrophora hamelii Brandt, Porphyrophora hirsutissima Hall, Porphyrophora sophorae Arch. and other species distributed in Eurasia and Africa. They are also called carmine worms. They were used to produce dye before the discovery of the Americas. But we will focus in more detail on the Mexican cochinea (Dactylopius coccus Costa).

Area

Biological description

Dactylopius coccus Costa inhabits cacti of the genus Opuntia. The body of the female is oval, 4-6 mm, covered with a white plaque with a lilac colour showing through. Under a microscope, short antennae and tiny feet ending in a single hook can be seen. Males are 1.3 mm long, red in colour. The colourless wings are covered with a fine wax powder and therefore appear white.

After emerging from the eggs, the wandering larvae spread through the opuntia thickets in search of food. Then the larva uses its proboscis to attach itself to a cactus stem, where it remains motionless and feeds on the sap of the plant. After a few days, the body of the female larva is covered with thin filaments, like a powder, for protection against predators.

After feeding, the males are enclosed in tiny white waxy cocoons, where their bodies undergo changes: they lose their mouthparts and form wings. They flutter briefly in search of mates, and die immediately after mating. Females of the Mexican coot may also make a short mating journey. They retain eyes, tendrils and paws ending in a tiny claw. These, considered more primitive, coccids are called worms. After mating, the females live another month, then lay eggs and die.

Chemical transformations

The bodies of female cochinea contain carminic acid (in the form of potassium salts), which belongs to the group of anthraquinone dyes. Its synthesis begins together with the formation of eggs and continues during the whole process of insect development, reaching the maximum concentration of muscle tissue. According to some scientists, carminic acid in insects neutralizes parasite attacks. Apart from carminic acid, other dyes - kermesic acid and flavono-kermesic acid - are contained in small quantities in cochineal.

To obtain dyes, female insects with eggs were collected. The cochinea was separated from the cactus with a sharpened stick, blunt knife or small panicle, killed by drying in the sun (or in ovens) and sold as shriveled "kernels".

To obtain carmine, cochinea is boiled in water, then the salt of carmic acid is precipitated with alum. Wool and silk are dyed with mordant (tin salts), obtaining a colouring that is resistant to light and washing. This dyeing is called 'Venetian purple'.

Purple and mauve shades can be obtained when the cloth is initially dyed with pastel and then with wheat. On white cloth can be achieved different shades (cherry, crimson) by adding to the dyeing solution of cochinea red tartar (a crystalline precipitate which falls out during the production of wine by alcoholic fermentation). Light grey, plum and golden-pink tones are obtained by adding to the cochineal solution marena and ink nuts in different proportions.

Carmic acid was first isolated in 1818 from cochinea by French chemists Pierre Pelletier and Joseph Cavantoux.

History

The people of Mexico in ancient times used cochinea as a dye. Analysis of fabrics found during excavations allows us to date the use of cochinea as early as the 3rd century B.C. By the time the Spaniards arrived, there were two centres (in the Andes and Mexico) where cochinea was specifically bred on Opuntia ficus-indica (L.) Miller) cacti. Since the early 19th century, Mexican cochinea has been bred in many parts of the world.

Purple dye, derived from Mexican cochinea, was first brought to Europe at the beginning of the 16th century as a gift to the king of Spain by conquistador Hernan Cortez. It had some advantages over Old World wheat dyes: the dye was brighter, the insect's life cycle was shorter (five generations could be obtained within a year), the dried bodies of insects had no fat that made it difficult to obtain the dye. Mexican cochinea gave dyers about 20 different shades of dye and ensured unheard-of savings. Within 20-30 years, the use of wheatgrass spread throughout Europe, Persia and Central Asia. In the 17th century, wheatgrass conquered China. In addition, wheatgrass gave wool dyers about 20 colours, making a splendid addition to an already quite wide range of madder-based colours.

With the advent of aniline dyes in the 19th and 20th centuries, the demand for cochinea fell dramatically. But it had a huge advantage. Cochinea was safe for humans, so in the 20th century, it was used again in perfumery and the food industry.

кошениль мексиканская 3.jpg

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Wild madder

Rubia peregrina L.

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Area

Biological description

The wild madder (Rubia peregrina L.) is an evergreen perennial plant of the madder family. The stem is creeping, 50-250 cm long. The evergreen leaves are leathery, oval-lanceolate and serrated along the edges, arranged in whorls. The greenish-yellow flowers are in axillary inflorescences. The fruit is drupe-like, black.

Chemical Transformations

The thick roots are harvested for dye, sized according to the thickness of the stem, after fruiting. Unlike dyer's madder, wild madder contains little alizarin. The main dyes are pseudopurpurine and purpurine. Pseudopurpurpurine makes fabrics red-pink, while purpurine is carmine red. Freshly ground roots or a powder of dried roots are used for dyeing. The powder is often fermented in warm water for 10-12 hours before dyeing.

History

The wild madder was harvested and even cultivated in the same areas and at the same time as the dyer's madder, which was sometimes lacking for the needs of textile production. It is mentioned in the works of Pliny the Elder and Dioscorides. The use of both plants was important because of the different concentrations of dyes in their roots and the shades they give fabrics.

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In Chinese medicine and Ayurveda, wild madder is used for its antibacterial and anti-inflammatory properties.

Madder

Rubiaceae

YamabikaY/Shutterstock.com

In the genus Rubiaceae, a large number of plants are suitable for producing red dye. This is why the family even gets its name from the Latin word ruber, 'red'.

Area

Biological description

Rubia tinctorum L. is a perennial herbaceous rhizomatous plant of the madder family. Shoots are climbing (due to hooked prickles on the stem), strongly branched, 1.5-2 m high. Leaves elliptic, dense, arranged in whorls. Small star-shaped yellow flowers aggregated in axillary umbrella inflorescences. The fruit is a black drupe.

Chemical transformations

To obtain the dye, the roots of biennial plants were peeled and crushed. The powder of the roots was placed in barrels for four years, where fermentation of the raw material, hydrolysis of substances (by bacteria), release and transformation of substances in the dye took place. Madder roots contain a number of dye precursors: alizarin compounds, pseudopurpurpurine, rubiadin, mungistin, chrystophin.

During fermentation or under the influence of acids, the alizarin compound breaks down into sugar and alizarin. And pseudopurpurine gives purpurine and carbonic acid when heated with water. At the same time, each dye with its own colouring affects the brightness, saturation and tonality of the colour. The use of madder in dyeing practice was based on the alizarin's ability to give bright coloured colours with different metallic oxides (mordants): with iron compounds it turns purple, with aluminium oxide - bright red and pink, with tin oxide - magenta.

Madder dye was widely combined with indigo and yellow dyes to produce dyes of various shades - from orange-red to almost black.

History

The method of dyeing fabric with madder is first described on a seventh century BC Babylonian tablet, preserved in the British Museum. Madder is mentioned as a dye in the writings of Pliny the Elder in the first century AD. Madder was widely used in the Greek and Roman world, not only in dyeing, but also in painting. Madder was sold both as a root and in a ground state.

The cultivation of madder spread throughout the Mediterranean, Western and Eastern Europe. In ancient times, it was introduced to China, Japan and India. After the discovery of the Americas, it was exported and cultivated in both Americas. Its cultivation ceased at the end of the nineteenth century, when the dye alizarin was artificially obtained.

In Russia, the study and attempted cultivation of madder began in 1745. The main plantations were concentrated in Crimea and Transcaucasia. Madder extracts, produced under the name of krapp, were most popular in the 19th century, before the era of aniline dyes. In the 18th and 19th centuries, madder was an export commodity that was exported along with furs and rhubarb to Western European countries. In the late twentieth and early twenty-first centuries, the cultivation of madder, not only as a dye, but also as a medicine, began to revive.

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Decoctions and tinctures of the roots and rhizomes of the plant are used in medicine for kidney diseases to eliminate stones. The composition and acidity of the soil in which madder is grown affects the colour of the dye.

Hexaplex trunculus

Hexaplex trunculus (L., 1758)

Area

Biological description

Hexaplex trunculus (L., 1758) - is a predatory marine gastropod mollusc. The spindle-shaped shell, up to 11 cm long, is formed by seven relatively convex ledge-like whorls, and the colouration varies greatly.

Chemical transformations

Harvesting of hexaplex trunculus is done either by hand by divers in shallow water or by using a net with crustacean meat as bait. The hypobranchial gland of hexaplex trunculus contains four different chromogens, two of which do not include bromine and two of which do. The predominance of indigo and 6-bromoindigo in it gives the dye produced from it a dark purple-blue colour.

History

Three dyes are often mentioned in the Bible: blue purple, purple-red and kermes. Fabrics dyed in these colours serve as draperies in the temple and are prevalent in the priests' robes. And the mantle of the high priest, as well as the ribbons by which the breastplate and diadem were fastened, were to be dyed only blue purple. Blue purple gradually disappeared after the eighth century.

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The mollusk is hermaphroditic, which means that it can alternately be male and female. The female produces more indigotin (blue dye), while the male produces only the purple-red 6,6'-dibromoindigo. The predominance of one dye or another also depends on the mollusk's diet and habitat.

Purple dye murex

Bolinus brandaris L.

Purple is a dye with shades ranging from purple-red to blue-purple, consisting of dyes chemically very similar to indigo and derived from the marine gastropod molluscs, the murex and purple clams. These clam species belong to the family Muricidae. Fabrics dyed with purple were a sign of wealth and were sold by the weight of gold or silver. Only emperors, warlords and priests could wear clothes made of purple. This dye gave fabrics lustre, and not only did not fade with time but also intensified when exposed to light. The colour range is from red to purple, purple to black, pink to reddish purple.

Area

Biological description

The purple dye murex (Bolinus brandaris L., 1758) is a predatory marine gastropod mollusc. Its shell is finger-like, needle-shaped, can reach a length of up to 9 cm, golden brown, with a long siphonal canal and a rounded body with a low spire.

Chemical transformations

The precursors of purple are concentrated in the mid-section of the hypobranchial gland of the living mollusc. The hypobranchial gland is a glandular structure located in the mantle cavity. It secretes a secretion that binds the small particles that enter the mantle cavity with the flow of water into larger clumps. The secretion contains a poisonous substance, murexin, which has a paralyzing effect on the bivalves that are the main prey of the murex. After the death of the mollusk, the precursors of murexin are hydrolysed by enzymes (purpurase) in contact with air oxygen, producing a greenish-coloured intermediate substance. When exposed to light and heat, the substance liberated sulphur, converting to 6,6'-dibromoindigo and dibromindirubin - the main substances in purpura. There was a terrible stench in the areas where ancient purple was produced.

The murex fishing season lasts from autumn to winter because in spring, during the breeding season, the secretory fluid of the molluscs loses its colouring power. As far back as Pliny the Elder described a method of fishing with a drag net, in which bait (fixed bivalve shells) is placed for predatory molluscs. The bivalves open up at sea and the murex attack them, extending the radula to pierce them. But, feeling the pain, the bait slams into the shell and the murexes are captured by their prey. On the shore the murex's shells are grinded together with the mollusk's body, then the remainder of the shell is removed. Often the shell is broken with a special knife or stone hammer and the gland is simply cut out.

The cloth was dyed in a solution of sea purple, sometimes repeatedly immersed in a vat, thus obtaining Tyr purple. The cloth dyed in Tyrrh purple could be dyed again with kermes after dressing in alum.

The following recipe for dyeing with purple in antiquity can be briefly introduced. A pulp of shells or separated glands from mollusks was put in a pewter vat, salt was added and the mixture was insisted in the heat for three or more days. The remains of the corpuscles were removed and lime was added to the dye. Then, fabrics and fibres were dyed by repeatedly dipping them into the dye vat.

History

Purple began to be produced in Crete in 1800-1600 BC. The culture of Tyrian purple spread later (in the 14th century BC) to Phoenicia, Egypt, then to the Middle East, the territory of modern Israel. The expression 'royal purple' appears for the first time on a Cretan line script tile from the 13th century BC, found in the Palace of Knossos. But it was the Persians who elevated Tyrian purple to the rank of royal cloth. Alexander the Great in IV century B.C. adopting Persian signs of power started the triumph of purple, first in Greece and then all over the Mediterranean. It was only in the second century A.D. that purple became available to all classes of society, but in limited quantities: it could be used as part of festive clothing (trimming the fabric with a small strip), and for home textiles (cushions, blankets, curtains). There have been cases of fraud where purple was substituted with cloth dyed with marena.

After the Arabs conquered Tyre in 640 the number of purple dyes dwindled in the eastern Mediterranean and with the fall of Constantinople in 1453 the last centre of purple production died out. Eleven years later, Pope Paul II confirmed the end of the 'purple age' with a decree authorising the replacement of purple with red dye, which was extracted from the insect kermes.

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Murex and other purple molluscs are part of Mediterranean cuisine.

Dyer's woodruff

Galium triandrum Hyl.

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The Rubiaceae family includes several species of galium, which along with madder were widely used in the dyeing industry. The dyer's woodruff (Galium triandrum Hyl.) is a perennial herbaceous plant up to 50 cm tall with a creeping, cord-like rhizome. The stem is ascending, glabrous, branched, tetrahedral. Leaves are linear, arranged in whorls of 6. Small white flowers on long tripartite pedicels, bearing three semisontics each. Fruits are double, wrinkled. It grows throughout Europe, in Western Siberia in steppes, among shrubs, on forest edges, in light pine forests

Area

Chemical transformations

The roots of the cinquefoil contain small quantities of alizarin, but purpurine and rubiadin are the main colouring agents. The roots of the cinquefoil are harvested in autumn, crushed and soaked for a day in warm water. The dyeing is done as with a madder. Crushed roots are soaked in water or kvass, brought to a boil, then the yarn is lowered into the vat. As in the case of the madder, a whole range of reds, oranges, pinks and their derivatives can be obtained, depending on the species of woodruff used, the age of the plant and the composition of the soil on which it grew, and the mordants used. All of these dyes are resistant to fading in the sun and when washed.

History

The natural dyes in the roots of galium were discovered experimentally when studying plants related to it. It was used throughout Europe, but was particularly popular as dyeing plants in Scotland, England and the Scandinavian countries. In some countries, cinquefoil was used in huge quantities. From as early as the end of the 17th century, acts were issued prohibiting the collection of woodruff. Many species of woodruff were introduced to North America, where they eventually became naturalized.

Galium

Rubiaceae

photo: M.Kulikova.

The Rubiaceae family includes several species of galium, which along with madder were widely used in the dyeing industry.

Area

Biological description, habitat, cultivation

Galium odoratum (L.) Scop. is a perennial herbaceous plant up to 35 cm tall with a slender, creeping rhizome. The flowering stems are erect, tetrahedral. Leaves are lanceolate, arranged in whorls of 6-8. Fine white flowers aggregated in paniculate inflorescences. The fruits are double, covered in hooked bristles. The plant contains a lot of coumarin and therefore has a pleasant fragrance. Occurs throughout Europe (rarely in the Mediterranean) in forests of various types. Naturalized in North America.

Galium verum L. is a herbaceous perennial herbaceous plant up to 120 cm tall with a creeping branched rhizome. Stems are numerous, erect, tetrahedral. Leaves are linear, with edges turned down, arranged in whorls of 6-12. Small yellow flowers aggregated in apical paniculate inflorescences. The fruits are double. Grows throughout Europe in meadows, glades, steppes, and brushwood.

Galium album Mill. is a herbaceous perennial herbaceous plant up to 130 cm tall with a creeping ligneous rhizome. Stems are ascending, tetrahedral, branched. Leaves are linear-lanceolate, arranged in whorls of 6-8. Small white flowers aggregated in multifloral paniculate inflorescences. The fruits are double. Grows throughout Europe in meadows, forest edges, light forests, in weedy places. Naturalized in North America and western Asia.

Galium sylvaticum L. is a perennial plant up to 120 cm tall. The stem is rigid, erect. Leaves are oblong-lanceolate, arranged in whorls by 8. Flowers are white, aggregated in corymb-like panicles. Grows in deciduous forests in Central Europe. Naturalized in North America.

Galium boreale L. is a herbaceous perennial plant growing up to 50 cm tall with branched shoots. The stems are rough with stiff bristles. The linear-lanceolate leaves are arranged in whorls of 4. Small white flowers aggregated in paniculate inflorescences. The fruits are double. It grows throughout Europe in meadows, on steppe mountain slopes, on forest edges and in light pine forests.

Chemical transformations

The roots of galiums contain small quantities of alizarin, but purpurine and rubiadin are the main colouring agents. The roots of the cinquefoil are harvested in autumn, crushed and soaked for a day in warm water. The dyeing is done as with a madder. Crushed roots are soaked in water or kvass, brought to a boil, then the yarn is lowered into the vat. As in the case of the madder, a whole range of reds, oranges, pinks and their derivatives can be obtained, depending on the species of woodruff used, the age of the plant and the composition of the soil on which it grew, and the mordants used. All of these dyes are resistant to fading in the sun and when washed.

History

The natural dyes in the roots of Galium triandrum were discovered experimentally when studying plants related to it. Galium was used throughout Europe, but was particularly popular as dyeing plants in Scotland, England and the Scandinavian countries. In some countries, cinquefoil was used in huge quantities. From as early as the end of the 17th century, acts were issued prohibiting the collection of galium. Many species of woodruff were introduced to North America, where they eventually became naturalized.

Pterocarpus indicus

Pterocarpus indicus Willd.

Photo: M. Kulikova.

Area

Biological description

Pterocarpus indicus Willd. or Indian sandalwood (Pterocarpus santalinus Blanco) is a tree up to 40 m tall in the legume family. Its wood is hard and red in colour. The leaves are unpaired, comprising 7-11 oval leaflets. The flowers are yellow, aggregated in panicles. The fruit is a pod with wing-shaped growths.

Chemical transformations

The wood of Pterocarpus indica contains santhalin, which stains fabrics red, as well as a number of isoflavonoids. The presence of tannin plays an important role in dye staining. The dye is not resistant to light. The wood is ground to sawdust and boiled for 1.5 to 3 hours in a solution of alcohol or an aqueous solution of sodium carbonate. The resulting decoction is strained, diluted with water and used to dye the fabrics etched in alum. In the past, to improve the dyeing agent, it was often mixed with walnut, alder bark and sumac. Dyeing with Pterocarpus can result in fabrics with bright red, brick red and garnet shades depending on the mordants used.

History

Pterocarpus as a colouring agent has been widely used in its natural growing regions. It was actively used in Europe in the 16th and 19th centuries.

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The wood of Pterocarpus indica is used for furniture, woodcarvings and musical instruments. It is a good melliferous plant. Decoctions of the leaves are used in folk medicine as an anti-inflammatory, diuretic and anti-allergenic.

Thais haemastoma floridana

Thais haemastoma floridana (Conrad, 1837)

Area

Biological description

Thais haemastoma floridana (Conrad, 1837) is a predatory marine gastropod mollusc. Shell height (thick-walled, robust) up to 8 cm. Shell colouring varies from grey-brown to white with occasional brown spots. The colouration of the mouth is pale pink to bright orange.

Chemical transformations

This clam has two dominant purple precursors: tyrindoxyl sulphate and 6,6'-dibromoindigotin. When staining, the dyes of this clam species and murex were usually mixed.

History

The shells of thais are found in archaeological excavations along with those of the murex in Crete, Southwest Asia and Asia Minor. Dyes from this mollusc were used to produce purple, which was popular in modern Morocco until the fifth century.

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Moroccans appreciate it as seafood.

Caesalpinia echinata

Caesalpinia echinata Lam.

Bolex Krul/Shutterstock.com

Area

Biological description

Caesalpinia echinata Lam. is a tree up to 30 m tall in the legume family. The wood is brownish when cut, turning red in the air. The trunk is covered in thorns. The leaves are double pinnately compound. Yellow flowers clustered in racemes. The fruit is a pod.

Chemical transformations

The core of the wood contains brazilin (a neoflavonoid), which can be extracted from the wood with hot water. With air oxygen or other mild oxidants, it is easily oxidised to brazilin.

The wood is ground into shavings and boiled for three hours in a large amount of water. The decoction is then left to mature for about a day to a month. Silk and wool pre-soak in alum (using salts of aluminium, tin, chromic acid or a mixture of these), then dye. The colour depends on the acidity of the mixture and the fixative used. Aluminium mordants in combination with Brazillin produce standard red colours while tin mordants lead to pink colouration. Dyeing is done in an acidic environment.

History

From 1500, after the discovery of Brazil, the Portuguese began importing cesalpinia wood into Europe. The local population widely used the dye for tattoos, which attracted the attention of Europeans. Thus, Portugal banned the importation of Brazilian wood, namely cesalpinia sappan from its East Indian colonies and actively exported the dye wood from Brazil. Spanish, Dutch and French smugglers also exploited cesalpinia. From the 16th century onwards, numerous Norman ships sailed between France and Brazil, quickly loading timber and trying to remain undetected by the Portuguese, who zealously guarded their colonies.

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Its wood is considered one of the best for making bows for stringed instruments as well as conductors' sticks. Its wood is distinguished by its hardness, lightness and elasticity.

Caesalpina sappan

Caesalpina sappan L.

фото: М.Куликова.

Area

Biological description

Caesalpina sappan (Caesalpina sappan L.), patanga, or gabana tree, is a tree up to 8 m tall in the legume family. The sturdy wood is dark red in colour. The grey bark is covered with thorns. The leaves are double-pinnate, up to 45 cm long. Lemon-yellow flowers gathered in clusters. The fruit is a pod.

Chemical transformations

The core of the wood contains brazilin (a neoflavonoid), which can be extracted from the wood with hot water. With air oxygen or other mild oxidants, it is easily oxidised to brazilin.

History

The first mention of its use in India dates back to the fourth century. In the sixth and eighth centuries, cesalpinia sappan was actively purchased from China and Japan. From the twelfth century onwards, Arab merchants imported cesalpinia sappan wood into Europe. Its use plummeted in the 16th century after the discovery of South America, when other Brazilian trees were imported from the New World.

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Cesalpinia sappan is used in Ayurveda. Used in cosmetology, it has antiseptic, astringent, anti-inflammatory and soothing properties.　

The wood is used in furniture manufacturing.

Other species, Caesalpinia japonica (Caesalpinia japonica Siebold & Zucc.) and Caesalpinia pulcherrima (L.) Sw. are ornamental plants widely spread throughout the world.

Woad

Isatis tinctoria L.

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Area

Biological description

Isatis tinctoria L. is a biennial of the crucifer family. It can grow to a height of 80 cm. The leaves are oblong-lanceolate, hairy, with the lower ones arranged in a rosette. In its first year of life, the vista forms a rosette of leaves, flowering and bearing fruit in the second. The yellow flowers form a panicle-like inflorescence. The fruit is a pod with narrow wing-shaped growths.

Chemical transformations

Woad leaves contain the glycoside indican, a colourless organic substance which is decomposed by enzymes into glucose and indoxyl. Indoxyl in an alkaline solution is oxidized by air oxygen to become indigotin, colloquially called blue indigo. Isatane B is also found in large quantities in woad leaves, from which indigo is also obtained by hydrolysis.

The freshly picked woad leaves are milled and soaked in vats for 2-3 weeks to allow the fermentation process to take place. The pulp is then milled into round balls which are left to dry for a few weeks. The raw plant bacteria Enterobacter agglomerans are responsible for the transformation of indicine and isatane B into indigo in the raw balls. The subsequent production of the colour falls on the shoulders of the dyers. The raw balls are crushed, moistened, and the second activation step in the process described above is performed. The resulting thick mass is suitable for dyeing.

History

Blue was the colour of the barbarians, who painted their bodies before the battle with dye derived from woad. It was not uncommon for them to make tattoos using a similar dye. For magical, military and medical tattoos woad dyes were allegedly used in ancient Egypt as well.

European tribes (Celts, Germans) widely used the sap from fresh woad leaves to dye cloth blue and green. Woad itself is widely grown in Europe, but from 1230 it was cultivated specifically to meet the demand for blue dye. It became a source of enormous revenues: 'blue gold' was exported to the East and its production dictated the fashion for blue fabrics. Producers of red dye (derived from moraine) began to incur losses. In the XIII-XIV centuries, dyers in many European countries were divided not only by the colours they could work with but also by the group of the dye. That is, some could dye fabric red only with moraine, others with imported wheat, and others dyed fabric blue with woad. It went so far that dyers were divided into the lowest category (they dyed fabrics in faded, quickly fading colours) and the highest (they could give fabrics a rich colour). Thus began the dyers' wars over the market, the use of water and the location of the dye house.

In many parts of Europe, centres were created for the cultivation of woad and the production of dye. The largest of these were Thuringia and the Duchy of Julich. They not only met the demand on their own territory but also supplied dye to Flanders, England, Scandinavia, Italy, Poland and other regions.

But the triumph of the woad did not last long. As early as the 15th century, a new dye came to the fore: indigo, derived from the leaves of the Indian indigofera shrub. And at the beginning of the 16th century, indigo, imported from the New World, filled the European market. The centuries-long struggle between woad dyers and indigo dyers ended in a total victory for the latter. Despite the high cost of the raw material, the persistence of indigo dye and its rich, bright colour prevailed. Its former glory was briefly revived when Turkish troops blocked the trade routes from Asia in the 16th century and during the Napoleonic wars in the early 19th century.

In the XVII-XIX centuries, a peculiar friendship emerged between woad and indigo derived from the indigofera: indigo starch was added to the same vat of woad (during fermentation) and thus a more persistent shiny blue fabric shade was obtained.

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The leaves and roots of woad are used in Chinese medicine for inflammatory conditions and colds. The seeds are used to produce oil. Woad is a melliferous plant.

Japanese indigo

Persicaria tinctoria (Aiton) Spach

High Mountain/Shutterstock.com

Area

Biological description

Persicaria tinctoria (Aiton) Spach is an annual plant with an erect stem up to 80 cm tall in the buckwheat family. The leaves are oval-ovate, pointing downwards at the edges. Small pink flowers aggregated in dense spike-like inflorescences, which together form panicles. The fruit is a nut.

Chemical transformations

The dye can be obtained in different ways, we will focus on the traditional Japanese method. The cuttings are cut, and dried and the leaves are separated. The leaves are placed in a 1-metre layer, sprayed with sake and poured over with water. Fermentation occurs due to the presence of bacteria in the raw material, and the temperature of the mixture increases. The mixture is stirred and new portions of leaves and water are added. The mixture is then covered with a straw blanket to keep it warm. Fermentation takes around 2-3 months. The compost is then bagged.

Often fresh leaves are used for dyeing. They are first milled with water to produce juice. This juice is then repeatedly soaked in cloths, alternating with placing them in the air

History

The use of Japanese indigo began in China about 4,500 years ago. The legendary ruler Huangdi issued a decree around 2600 B.C. stating that the outer garments of the Chinese must be sky-blue. In the fourth century, Japanese indigo began to be cultivated in Japan. The seeds were brought to France by Jesuit missionaries in the 18th century, and in 1776 D. Blake brought the plant to England. In 1833, the cultivation of Japanese indigo began in the Caucasus. Europeans studied the plant extensively in order to find cheaper raw materials to produce a blue dye.

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In Eastern (especially Chinese) medicine, fresh leaves are used for fungal skin diseases, infusions are used for fevers, chest pains, inflammatory diseases of the mouth and throat.

Indigofera tinctoria

Indigofera tinctoria L.

My-ma-le-wow/Shutterstock.com

Area

Cultivation

Indigofera was introduced into cultivation about 2,500 years ago in countries with tropical climates.

Biological description

Indigofera tinctoria L. is a shrub up to 2 m tall in the legume family. Leaves are unpaired pinnatipartite with 4-7 pairs of leaflets. Leaflets elliptic, glabrous above, with tightly adpressed hairs below. Light purple, moth-like flowers in pile-like inflorescences. The fruit is a pod.

Indigofera suffruticosa Mill. is a semi-shrubby shrub, up to 1 m tall, growing in dry fallow fields and along roadsides. The flowers are salmon-coloured.

The generic name Indigofera is made up of two Latin words meaning 'blue dye' and 'bring, bear', which together can be interpreted as 'a plant that brings forth blue dye'.

Chemical transformations

The leaves of all members of the genus Indigofera contain the glycoside indican, a colourless organic substance which is decomposed by enzymes into glucose and indoxyl. Indoxyl in an alkaline solution is oxidized by atmospheric oxygen to become indigotin, colloquially called blue indigo.

Freshly cut stems of indigofera (or crushed leaves) are soaked in vats of pure water. The bacteria present in the plant material release substances (enzymes), triggering the fermentation process and converting the sugars into acids. After 8-10 hours, the extract obtained from the plant is poured into another vat, lime is added (to neutralise the acid) and the plant is stirred intensively for two hours. On contact with air, the yellowish-green liquid turns blue, a precipitate precipitates, which is filtered and dried. This is how indigo is made.

Indigo dyes are water insoluble pigments. In an alkaline environment, a water-soluble form of the dye is formed, which has an affinity to the fibres of the fabric. Already on the fibres the dye changes back to an insoluble form when oxidised by air oxygen.

Previously, the plant was treated with urea to release pure indigo - producing a colourless, soluble form (leucoindigo). The plant fibre fabric was soaked in it and left to soak in the sun to oxidize with air oxygen and develop a permanent blue colour. The highly alkaline environment required for indigo dyeing precludes its use in dyeing animal protein fibres (wool and silk).

Many shades of blue may be obtained from indigo, ranging from pale blue to deep blue, almost black. Indigo has also been used to dye cloth green. Blue cloth was soaked in yellow dye and pre-soaked in alum. The initial intensity of blue colouring depended on the shade of green tone. Indigo was also used as a base to give a violet hue, with further dyeing with wheatgrass.

History

Indigofera produces two dyes, basma and indigo. The finely crushed leaves of indigofera are called basma. Basma is a natural remedy for darker shades of hair but is usually used in combination with henna. If you dye the colour pure, you can get a blue-green hair colour. When beetroot juice or coffee bean powder is added to the basma, various shades can be achieved. Owing to its tannins, basma has long been used as a cosmetic to nourish the scalp, strengthen the hair and eliminate dandruff.

Blue indigo is a very persistent dye that has been used for dyeing fabrics since ancient times. This dye is particularly widespread in India, which is why fabrics dyed blue are very popular in the plant's native land. The peoples of the Middle East used to purchase indigo from India. The first written reference to indigo dates back to the 7th century BC. It was discovered on Babylonian clay tablets. It was widely disseminated in China. Phoenician traders brought indigo to the Mediterranean. In ancient Greece and Ancient Rome, indigo was familiar but blue fabrics were seldom used. For the Romans, blue was the colour of the barbarians, who painted their bodies before battle with blue dye (derived from the woad). It was also the colour of mourning, death and bad taste. The vegetable origin of indigo has long been a mystery to Europeans. They believed the dye to be of mineral origin and called it "Indian stone". Only Marco Polo established its plant origin in the thirteenth century.

Its triumphal march across Europe began in the 13th century. This pigment was more expensive than woad-based dye, but coloured fabric better (the colour didn't fade in the sun or wash). For nearly two centuries, woad merchants have been harassed by the authorities and tried to prohibit the use of indigo. The overseas competitor, the "devil's dye", was undermining their economic stability. The problem was resolved when the Turkish army effectively closed off trade routes from Asia. But as early as the 16th century, indigo began to be imported from the New World, where other species of indigo were discovered, such as the semi-bush Indigofera. Analysis of fabrics has shown that indigo had already been in use in Peru for more than 6,000 years. In the 17th century, importation of the dye from India was resumed but indigo has again been banned in European countries. It was only after 1737 that European dye mills switched over to dyeing indigo fabrics completely.

In 1882, indigo began to be produced artificially, which made it much cheaper to produce blue fabrics and reduced the use of natural dyes.

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Indigofera leaves are widely used in Indian medicine. They are used for liver diseases, as a bactericidal and antipyretic. Externally, they are used to heal wounds, boils and dermatoses. The first jeans were dyed with indigo. And by mixing indigo with starch, linen blue was made.

To this day, chemical analysis of the dyed blue fabric makes it impossible to judge the type of plant from which the dye was derived.

Externally, indigofera is similar to its close relative, Indigofera gerardiana (Wall.) Baker, which is often cultivated as an ornamental plant.

Logwood

Hematoxylum compechianum L.

Area

Biological description

Logwood (Hematoxylum compechianum L.) is a tree up to 12 m tall in the legume family. The leaves are paired-petioled. Its flowers are yellow, in clusters. The fruit is a pod.

Chemical transformations

The crushed logwood a source of the valuable blue dye. When freshly sawn, the wood is blood-red in colour, but when the pigment is oxidised in the air, the colour of the trunk changes to dark purple and then dark blue (almost black).

To obtain the dye, the wood is ground into shavings and fermented. During this process, the hematoxylin in the wood is oxidized in the air and transformed into the dye hemathein. Hematoxylin is currently obtained by extraction with ether from the wood.

History

Logwood was first brought to Europe by the Spanish in the 16th century, almost immediately after the discovery of the New World. There was a steady demand for it, but it did not take off easily. For example, the English Parliament banned the use of imported logwood, allegedly because of quick paint evaporation and health hazards. But in fact, the reason was economic: trade in kampeche was a huge earner for the Spaniards, who for a long time enjoyed a monopoly of it in Europe.

Logwoodwas often counterfeited by fraudulent dyers. It was applied to fabric pre-dyed with woad or indigo to obtain a durable black colour. To confirm this, conscientious dyers would leave a piece of fabric undyed with logwood so that the blue would protrude. But counterfeit dyers, saving on expensive indigo, simply dipped the edge of the cloth in blue dye and dyed the rest of the cloth with logwood. In a few days, black would turn into orange.

To Russia logwood became imported from Europe during the reign of Peter I, when the country gained access to the Baltic Sea.

Logwood was used to dye silk, wool and cotton into grey and black colours. Unfortunately, the dyeing of silk was not very durable. As a blue dye, it was used as an undercolour mixed with other dyes. Depending on what was made the preliminary dressing of the fabric, received different shades: blue-black colour with chrome dressing, blue with alumina dressing, purple with tin dressing, greenish-black with copper dressing, black with iron dressing. Mixed mordants were used for dyeing wool and fur - iron-copper and chrome-copper which gave more lightfast colours than simple mordants. Dyeing was a long and complex operation.

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The sap of the bark makes a black and purple Chinese ink. Logwood is used for furniture, handicrafts and parquetry. Hematoxylin is used to colour microscopic preparations.

Wrightia

Wrightia tinctoria (Roxb.) R.Br.

Somsak Detchwatin/Shutterstock.com

Area

Biological description

Wrightia tinctoria (Roxb.) R.Br. is a deciduous shrub or tree 3-5 m tall in the Cuthrus family. The leaves are ovate, 10-20 cm long and 5 cm wide. White flowers aggregated in corymb-like inflorescences. The fruit is a hose. The seeds have hair-like outgrowths.

Chemical transformations

The wrightia leaves contain the glycoside indican, a colourless organic substance which is decomposed by enzymes into glucose and indoxyl. Indoxyl in an alkaline solution is oxidised by air oxygen to become indigotine, commonly known as blue indigo.

History

The plant is used in places where it grows naturally as a blue dye.

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Wrightia is used in traditional medicine in India (Ayurveda). The leaves are used for toothache and hypertension, the bark and seeds for flatulence, dyspepsia, fever and skin diseases. Wrightia wood is also used for carving.

Strobilanthes

Strobilanthes cusia (Nees) Imlay

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Area

Biological description

Strobilanthes cusia (Nees) Imlay is an herbaceous perennial in the Acanthus family. A upright, branched plant, up to 1.5 m tall. Stems with brown pubescence. Leaves large, up to 20 cm long, elliptical. Blue flowers aggregated in spike-like inflorescences, combined in panicles. The fruit is a capsule. The plant dies off after flowering.

Chemical transformations

The leaves and stems of Strobilanthus contain glycoside indican, a colourless organic substance that is decomposed by enzymes into glucose and indoxyl. In an alkaline solution, indoxyl is oxidized by atmospheric oxygen to become indigotene, commonly known as blue indigo.

To obtain the dye, the upper parts of the shoots are cut off before flowering and boiled in vats over low heat. The resulting concentrate (indigo) has a deep blue, almost black colour. It can be stored without preservatives for more than a year.

History

Formerly cultivated on an industrial scale in India and China. In Europe, it can only be grown in a greenhouse as an ornamental flowering plant.

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Strobilanthus is widely used in Chinese medicine. The stem and leaves are used as an antipyretic and the rhizomes as a treatment for epidemic diseases.

Dyer's weed

Reseda luteola L.

Area

Biological description

Reseda luteola L. is a biennial plant of the Reseda family. It forms a rosette of leaves in the first year of its life and develops flower stalks in the second year. The stems are erect, branched at the top, densely oriolate, up to 130 cm tall. The leaves are whole, linear-lanceolate, sessile, with two small, spiny teeth. Inflorescence makes up half of the flower-bearing shoot, spike-like, sometimes branched in the lower part. Flowers are four-membered, yellow, small, and almost sessile. The fruit is a capsule.

Chemical Transformations

The whole plant is used to obtain the dye. The plant is harvested at the end of the second year of its life, when the bolls have developed a yellowish colour. The plant can be dried in bundles outdoors, but this reduces the total dye content. Drying in a desiccator or freezing the plant is preferable to preserve the dyes.

Reseda contains luteolin, which belongs to the flavonoid group (plant substances that are important for fermentation processes). It is found in the plant both as a free form and as a glucoside. The reseda dye was studied and isolated in the early 19th century by the French chemist Michel Chevreul. Luteolin is also found in dyer's broom (Genista tinctoria L.) and leaves of foxglove (Digitalis L.), which have also been used since ancient times to produce yellow-orange dyes that are resistant to burnout.

The bunches of reseda are boiled in cauldrons for about an hour, then the resulting decoction is filtered. The fabric, previously pickled in alum (aluminium or tin) and tartrate (a crystalline residue that precipitates during the alcoholic fermentation of wine), is repeatedly dipped in the hot reseda decoction until the desired colour is achieved. At high temperatures, the bond between the dye and the monosaccharide is broken and the dye fixes to the fabric. The dye forms insoluble, stable complexes with heavy metals (mordant). Reseda dyeing imparts a variety of shades of yellow to the fabric: lemon yellow, sulphur yellow, golden yellow and saffron yellow.

To obtain shades of green (watery green, bright green, grass green) fabric is dyed with reseda after pre-dyeing with indigo in different shades of blue. Reseda decoction is mixed with Brazilian wood decoction to produce a golden brown colour. Olive shades are obtained by combining reseda and campesia wood, orange shades are obtained by adding madderwood.

History

In Europe, reseda has been used since ancient times and was popular among the Hellenes and in the Roman Empire. It is well known that it was cultivated in Palestine and Egypt as early as the 2nd and 3rd centuries. In Europe in the Middle Ages, dyeing fabrics with reseda dye became of particular importance as evidenced by the numerous dyeing recipes which have survived to this day, analysis of fabrics and archaeological data. Reseda was an export item, widely used by dyers of the Ottoman Empire. The plant was cultivated until the end of the 19th century, when it was replaced by quercitron dyes derived from the bark of the velvety oak (Quercus velutina Lam.), which grows in North America.

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In traditional medicine, infusions of the roots and leaves of dyer's weed have been used as a diaphoretic, diuretic and anthelmintic.

Smoke tree

Cotinus coggygria Scop.

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Area

Biological description

Cotinus coggygria Scop. is a branchy shrub or tree up to 5 m tall in the sumach family. The leaves are large, ovate, and turning pink-red in autumn. The flowers are numerous, small, pentamerous, yellowish or greenish-white, gathered in loose, paniculate inflorescences, 15-30 cm long. The fruit is a drupe.

Chemical Transformations

The wood of the smoke tree contains fisetin (flavone), which was isolated by Michel Chevreul in the early 19th century, and the orange dye sulphuretin (auron), isolated in the 20th century. The smoke tree wood also contains tannins, which contribute to staining and enhancing yellow and brown colours. Fustic yellow dye is obtained from the wood.

The leafy shoots contain a large number of colouring substances (flavonols fisetin, myricetin, quercetin, kaempferol and others) as well as tannins. They were used for tanning leather and dyeing it yellow and red.

To obtain the dye, the wood was ground to sawdust and boiled. Fabrics, previously treated with alum, were dipped into vats with the decoction, sometimes repeatedly. To obtain various shades, from light yellow to dark brown, from olive to grey-brown, rhubarb, oak ink nuts, dyer's wood and campesian wood were added to the smoke tree decoction. Marene and kermes were added to produce orange shades.

The smoke tree was more economical than other plants with yellow dyes, but the resulting colour easily faded in the light.

История красителя

In Mediterranean Europe, the tannery was one of the main sources of yellow dye during the Middle Ages for all types of fabric. From the 17th century onwards it was sidelined due to its unstable dyeing, but it was often used to produce orange fabrics, which greatly saved red dyes (e.g. cochineal). The smoke tree was actively used for dyeing carpets in the Ottoman Empire.

Near Moscow, under Tsar Alexei Mikhailovich in the 17th century, a saffiano factory used "svyatogorsk leaf" as tanning agents and dyes - it was nothing other than the leaf of the smoke tree, which was collected by the monks of the Svyatogorsk monastery.

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Due to the presence of tannin in its leaves, it is used in medicine as an astringent, anti-inflammatory and antiseptic. It is used externally in the form of solutions and ointments for inflammatory diseases of the mouth, nose and throat, burns, ulcers, fissures and sores. For internal use, it is used for gastrointestinal catarrh and poisoning with salts of heavy metals and alkaloids. It is widely used in landscaping, to create shelterbelts and to stabilise soil on slopes and embankments.

Sumach

Rhus coriaria L.

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Area

Biological description

Rhus coriaria L. is a shrub or tree up to 8 m tall in the sumach family. Its leaves are large, unpaired, consisting of 9-17 leaflets with a coarsely serrated margin. Flowers are unisexual, small, and aggregated in large conical panicles. Staminate flowers are clustered in loose "male" inflorescences, and pistillate ones in denser "female" inflorescences. The flowers have double pentameric perianths, yellow-green. The fruit is a small, dried reddish-brown seedpod.

Chemical Transformations

The dyeing raw material is the leaves. The leaves were collected in two ways. In midsummer, olive branches were cut and dried in bundles, then the leaves were shaken off. In early autumn, the leaves were harvested by hand from the newly grown shoots.

The leaves contain gallotanin, flavonols (fisetin, myricetin, quercetin, kaempferol and others) as well as tannins. Gallotanin stains fabrics brown. The leaves were boiled in water, resulting in a decoction, which was then strained and used as a yellow-brown dye. If the cloth was dyed with sumach and then with madder, a "Turkish" red was achieved. If the fabric was firstly stained with iron, it would lead to grey and black colours; in combination with marena on iron mordant, it would lead to greyish-blue colour. Adding sandalwood resulted in chestnut, bronze and garnet hues.

The bark of the sumach stem was often used for yellow; the bark of the root and the fruit were used for red.

History

In ancient times, sumach was known to dyers in Egypt and Greece. Theophrastus in the third century B.C. and Pliny the Elder in the first century A.D. mentioned sumach when referring to tanning leather. The Arabs cultivated sumach for tanning purposes. In Europe, sumach was especially valued since the 16th century as a source of permanent black dye. In the Orient, sumac was used to dye carpets yellow and red (in combination with madder), and black was used to dye scarves, which women wore outdoors. One of the major exporters of sumach to Europe before the Second World War was Morocco.

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The tannin-rich leaves of sumach are used in medicine as an astringent for diarrhoea, as a styptic, and as an antidote for poisoning by alkaloids and heavy metals. Powder of dried fruits of sumach is used as a spicy seasoning for meat and fish dishes.