Manufacturer and builder 11, 1869
Two German chemists, Messrs. Graebe and Liebermann, have succeeded in manufacturing " alizarin," which does not differ from the pigment extracted from the root of madder either in its chemical or physical properties. The method of manufacture is a secret as yet; all that the above gentlemen have made public is the fact of its being made out of "anthracene." This is a body consisting of carbon and hydrogen, closely resembling "naphthaline," and occurring together with the latter hydro-carbon in coal-tar. It has a high fusing point, (210° C.,) and a higher boiling point than quicksilver. It is, therefore, obtained from the heavy carbons of tar, while the lighter oils yield the material for the manufacture of "aniline colors." Up to the present time the heavy constituents of tar have bad no other value except for manufacturing asphaltum or being used as fuel. It is to be hoped that the utilization of this class of tar-oils will be developed on a commercial scale. The patent right for different countries is already secured by the above gentlemen, and will most likely be a source of ample remuneration to them. "Alizarine" is the stuff extracted from the root of madder, which furnishes the purest colors. Their superiority consists in their great resistance to the changing influence of sunlight, to which the aniline colors are unfortunately subject. Therefore a great gain in chemistry has been achieved, if the basis of this class of pigments can be artifically manufactured. But the importance of this discovery does not end here; much will be gained for national wealth in an indirect way. All the lands required for the cultivation of the madder will now be rescued for the production of food.
One important feature of this new industry is the fact that its raw material is a waste product of another manufacture. The coal-tar produced in the manufacture of illuminating gas, and formerly considered worthless, furnishes the raw oils for the brilliant aniline red, blue, violet, brown, yellow, black, white, etc., and the refure of this industry will now yield the raw material for the manuvature of madder colors. Who will now doubt the possibility of manufacturing in our laboratories at no distant day, from the fossil vegetation of geologic ages, even such coloring matters as indigo, hitherto the exclusive property of the living vegetable kingdom?
- Berlin corr. of Liepzig Maschinen Constructeur.