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William Perkin's Original Mauve Dye
From: Science Museum
| By:
Derek Robinson |
EDITOR'S INTRODUCTION |
William Perkin, a young chemistry student, was trying to discover how to synthesise quinine, a cure for malaria. Through this research he accidentally discovered the formula for producing synthetic mauve dye. Recognising its potential economic value, Perkin patented the dye and sold it on a large scale to the textile industry--an event that marks the beginning of the commercialisation of scientific invention. Derek Robinson of the Science Museum tells the story of a milestone in nineteenth century technological process. |
...if your discovery does not make the goods too expensive, it is decidedly one of the most valuable that has come out for a very long time. This colour is one which has been very much wanted in all classes of goods and could not be obtained fast on Silks, and only at great expense on cotton yarns. |
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| Sir William Perkin (1838-1907). | |
 o wrote Robert Pullar of John Pullar and Son, a leading firm of Scottish dyers, on 12 June 1856 following evaluation of fabric samples treated with mauve dye developed by WH Perkin. Some 18 months later this novel chemical product was being despatched from the Greenford Green factory of Perkin and Sons, having been bought by the largest silk dye works in London, an event now reckoned a milestone in nineteenth-century technological progress. Not only was this the first step in the industrialisation of organic chemistry but also the beginning of the commercialisation of scientific invention. |
Before this time dyestuffs were virtually all of vegetable or animal origin and their variety had not increased since the Middle Ages, despite intense efforts at improving methods of dyeing in the wake of the vast growth of textile manufacture during the Industrial Revolution. The initial context of Perkin's discovery was however quite unrelated to these efforts. William Henry Perkin (1838-1907), the son of a builder, showed a keen interest in chemistry from an early age and enrolled at the Royal College of Chemistry in 1853 where he attended the lectures of the German chemist AW Hofmann (1818-92), renowned for his research and teaching abilities. |
By the middle of the nineteenth century quinine was much in demand for the fight against malaria, but it was expensive. As a result Hofinann and a number of other chemists were investigating alternatives. From their very limited knowledge of the relationship between chemical composition and molecular structure it was not unreasonable for Hofinann to speculate in 1849 that quinine might be synthesised by the addition of water to naphthylamine, a substance obtainable from coal tar. |
In 1856 Hofmann's young research assistant, Perkin, resolved to attempt a synthesis based upon the addition of oxygen rather than water, selecting as his starting material allyltoluidine, which can also be obtained from coal tar.  Perkin undertook the oxidation at home, having in his enthusiasm for research equipped part of a room in his father's house for this purpose soon after beginning his studies under Hofmann. Working during the Easter vacation of 1856 his oxidation yielded none of the desired colourless quinine but only a dirty reddish-brown sludge. Accordingly he repeated the oxidation with the simplest base available from coal tar, aniline. The product this time was a black precipitate, which upon drying and treatment with methylated spirit, yielded an intense purple solution. Perkin found to his surprise that it dyed silk a beautiful colour and better resisted the fading effects of light than existing dyes used at that time. |
The 18-year-old pursued his discovery with the vigour of youth and the wise counsel of those in the dyeing industry with whom he was put in contact.  A provisional patent was deposited in London by 26 August of the same year and the final version sealed the following 20 February. His resignation from his post at the Royal College of Chemistry in October 1856, which Hofmann regarded as foolhardy, further testified to Perkin's commitment to make money from his synthetic dye. To produce the dye on a commercial scale required Perkin's father to recognize that his son's interest in chemistry had not been in vain, as he once had feared, and that the necessary capital expenditure would be a sound family investment. This proved to be a wise judgement. |
Perkin's discovery gave impetus to a new coal tar dyestuffs industry in which the level of protection afforded by patents was much less than it is today.  Fortunately whilst slight modifications of the original process became rife, none outdid the economy of the original method. In addition Perkin kept up his research activities and introduced new colouring materials himself, notably Britannia Violet in 1864, derived from magenta. This helped to keep the Greenford factory operating at a profit as more brilliant dyes displaced mauve from the market after a span of less than ten years. |
In 1869 Perkin devised two new methods which allowed the economic manufacture of alizarin, the natural colouring matter of madder, the prime red dye of the period, the synthesis of which had been reported by Graebe and Liebermann in 1868 but by a process too expensive to be of commercial interest. By the end of 1869 Perkin's company had made its first ton of alizarin, expanding output to over 200 tons per annum by 1871. |
Perkin had however always hoped to devote himself completely to pure research and by 1873. at the age of thirty-five, he found that his factory and patents could guarantee his 'retirement'. He sold his interests the following year. This early work was the foundation of the artificial dyestuffs industry we know today. However, British industrialists failed to build on Perkin's work. As a result, Germany, whose scientists were in the forefront of new branches of chemistry, soon took the lead in the production of artificial dyes. |
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