Art Chowder May | June, Issue 27 | Page 35

While the mystery of how the craft of dyeing came about remains lost 3 , there is more to it than finding out which colors or dyestuffs may have been used first. Few dyes, with the most notable exception of indigo, inherently stick to the fabric fibers without an intermediary agent known as a mordant, which bonds to both the dye and the fiber, like a sort of glue. The puzzle then would involve how the first dyers discovered what would work as mordants. There are spotty references to dyes among some classical authors and in medieval manuscripts. During the Middle Ages and Renaissance a thriving textile industry flourished throughout Europe. The craft guilds reigned and the secrets of their know-how were guarded against interlopers. The first printed practical guidebook on dyeing, published in Venice in 1548, was the Plictho of Giovanventura Rosetti, subtitled Instructions in the Art of the Dyers Which Teaches the Dyeing of Woolen Cloths, Linens, Cottons, and Silks by the Great Arts as Well as by the Common. This “great art” of dyeing can be witnessed in paintings of the aristocracy in their sumptuous attire and the magnificent tapestries of the period. The common method practiced by the peasants who spun and wove their own clothes depended on the sources they grew in gardens or gathered from open fields and woods. Even as the Industrial Revolution was taking hold in the mid-19th century, the dye trade continued very much as it always had with natural dyes, 4 but this was about to change. In 1856 young English chemist (he was 18) William Henry Perkin was trying to synthesize the natural anti-malarial drug quinine in his London home lab when he discovered by accident that the coal tar derivative aniline could, by a certain process, be made to produce an intensely purple color: mauve (from the French word for the color of the purplish mallow flower). In no time he was able to put the dye into industrial production. There had been nothing like it since the immensely expensive Tyrian purple of the Roman Caesars, 5 but now it was available to the masses. Mauve became a sensation, not only making its discoverer wealthy but also giving his name a sure place in the annals of chemistry. The Triumph of Fame ca. 1502–4  Tapestry Wool, silk (6-7 warp threads per cm.)  141 1/2 x 132” (359.4 x 335.3 cm)  Metropolitan Museum, New York The Annenberg Foundation Gift, 1998  Accession Number: 1998.205  The beautiful blue here is very likely woad, very similar to indigo, which was widely cultivated in Europe in the Middle Ages. Its use required considerable care and expertise. In 1869 Perkin took the industry a step further when, using the coal tar derivative anthracene, he synthesized the red coloring agent from the traditional dye from the root of the madder plant: alizarin. Because this could be done more cheaply on a coal based industrial scale instead of an agricultural one, the madder growing industry, with few exceptions, came to an end. With ever increasing understanding of organic chemistry, the replacement of natural dyes by synthetic ones came about rapidly. Coal tar is made available mainly as a byproduct of the coke industry, essential for making steel. A ton of coal yields 70-100 lbs. of tar, but the massive scale of the industry means that there is a great deal of it to work with. Coal tar is made up of various organic compounds that are processed to make molecular building blocks for use in all sorts of things: pharmaceutics (like ordinary aspirin), insecticides, solvents, synthetic resins, explosives (TNT), and much more. May | June 2020 35