Dyeing with fruit and rhubarb
Anyone, who has removed the seeds from a pomegranate and, in doing so, has inadvertently got some of the delicious juice on their clothes, knows that the accidental batik-like colouring is damnably intense. No wonder, then, that this fruit has something of a reputation in the world of dyeing.
“The pomegranate has been used to dye clothing for thousands of years,” says Cornelia Westfehling of the Cologne fashion label Lanius. And, as a result, woollen clothing and oriental carpets have been dyed yellow, yellowy-red and dark blue, using pigments from the skin and juice of the pomegranate. All sorts of forest and meadow plants have also been used, including elderberries (red-violet), nettles (green) and cranberries (pink).
Because, however, the pigments that are derived from plants do not “adhere” very well to fibres in the long term, dyed textiles have traditionally been pre-mordanted with metals such as copper, tin or aluminium. Not only did this pollute the environment, it did nothing for delicate noses either. “In the Middle Ages, dyers, who mordanted and dyed textiles, were located outside of towns, because of the unbearable smell,” explains Dr Volker Schröder from the professional association of the German chemical industry, TEGEWA e. V.
Light, sweat, washing: every dye’s nemesis
Although dyed in a foul-smelling suburb, clothing then made its way directly into the wardrobes of the upper classes, for the rule in those days was that the emperor’s new clothes were brightly coloured, whilst the ordinary people wore grey! “Brightly coloured clothes, dyed with natural pigments, were a privilege enjoyed by the rich, the nobility and the military,” says Schröder. Above all, this was because dying with natural pigment extracts has always been a hugely laborious process. Not only did each type of fibre, whether silk, cotton or man-made fibre, need its own type of dye, it also needed its own dyeing process. The red and blue uniforms of Napoleon’s Grande Armée were dyed with vegetable dyes and can be regarded as an early mass market for natural dyes and dyeing.
But dyeing of textiles only really became a mass phenomenon in 1879, when researchers at the Baden Aniline and Soda Factory, better known as BASF, succeeded, for the first time, in synthesising the natural indigo pigment in the laboratory, with the result that it could be used for a broad-based target group. The pigment is normally extracted from the Indian indigo plant and traces have even been found on the wrappings of Egyptian mummies. Nowadays, it is largely worn by the living: synthetic indigo is present in every pair of blue jeans. But why isn’t plant-based indigo used? “Long-term colour brilliance, wash-resistance and evenness of the dye can only be achieved in large quantities of textile with synthetic dyes,” says Schröder. Moreover, because of their chemical composition, synthetic dyes adhere better to the material. “They don’t bleed out so quickly,” says Schröder, “when light, sweat and the washing machine conspire against them.”
Naturally – I dye naturally
According to Greenpeace, more than 100 billion new items of clothing were produced worldwide in 2014 alone. For the most part, they are chemically dyed, with only a few of them able to be left undyed like the trousers and smocks of the Middle Ages. Lanius now want to bring a tiny proportion of this huge mass of synthetically dyed material into the camp of natural pigments. Recently, the fashion label has, therefore, been working with a textile company in South Korea, whose identity is to be kept secret. After six years of intensive development work, their researchers have apparently found a silver bullet for getting textiles to take natural vegetable dyes on a large scale and for ensuring they remain subsequently stable. How? “They are keeping the process a secret – but we have been allowed to take a picture of the machines that have been specially developed for industrial dyeing with natural dye extracts,” says Lanius’ representative, Westfehling.
This secret dyeing process is likely to appeal most to operators of ‘green-fashion’ boutiques, supporters of fair and sustainable fashion. And for good reason. According to Westfehling, it means that up to 30 per cent less energy is required; and the need to use chemicals, it is suggested, disappears completely. Ten of the 100 Lanius items for the 2019 summer season, including tops, skirts and jumpsuits, are intended to be the first to be dyed using vegetable dyes: the wild madder root gives rosé; pearl is created with a combination of turmeric, pomegranate and the polygonaceous Himalayan rhubarb plant; and the foundation stone for all natural dyeing – the indigo plant – gives us blue.
Title image source: NordWood Themes on Unsplash