Embedded Files
Alizarin was the first laboratory synthetic of a complex, naturally-occuring organic chemical product This important red dye is naturally obtained from the root of the madder plant. The madder red, second in importance only to indigo blue, had been used as a versatile dye for hundreds of years and is best known for its application in production of the famous Turkey red cloth. By clever application of the agents used to fix the dye to cloth, various shades and hues could be achieved from the same dye.
In 1856 the first commercially successful synthetic dye, mauve, was serendipitously discovered by British chemist William H. Perkin, who recognized and quickly exploited its commercial significance.
The chemical synthesis of alizarin was achieved in early 1868 by Carl Graebe and Carl Liebermann , who were research assistants of the chemist Adolf Baeyer. The significance of this achievement lay in the tremendous industrial importance of the natural dye, which was often applied using high-speed printing machines that colored millions of yards of cloth. As an outcome of the synthesis, alizarin was manufactured on vast scales in Britain and Germany, which in a flash, almost wiped out much of the cultivation and trade in the natural dye. This success was the main stimulus for the emergence of the synthetic dye industry, which transformed coal tar waste into alizarin and a myriad of other colored textile dyes. The early dyes were based on the chemical known as aniline, which gave its name to the industry.
The synthesis of alizarin stimulated scientific studies into the chemical constitutions and molecular structures of both natural products such as alizarin and indigo, and others without analogous colors in nature. In 1868, only a partial structure could be drawn for alizarin. Six years later, the modern structure of alizarin was published by Adolf Baeyer and the industrial chemist Heinrich Caro at BASF, a chemical company based in Ludwigshafen, Germany.
This advance drew on, and in many ways reinforced, the acceptance of Kekulé’s famous six membered benzene ring (used as a solvent for organic reactions) of 1865. It also led to scientific studies into all novel colorants, such that within a few years it was possible to create color by design. Synthetic dyes represented the very first high-tech science-based industry.
This revolution in the production of textile dyes, which began with synthetic alizarin, and its implications for global industries and economies, as well as for progress in science and technology
Early commercial dyes.
Page updated
Report abuse