Chay Root
(CHAPTER I. The Anthraquinone Group.)
(Osa artikkelista)

The Natural Organic Colouring Matters
Arthur George Perkin, F.R.S., F.R.S.E., F.I.C., professor of colour chemistry and dyeing in the University of Leeds
Arthur Ernest Everest, D.Sc., Ph.D., F.I.C., of the Wilton Research Laboratories; Late head of the Department of Coal-tar Colour Chemistry; Technical College, Huddersfield
Longmans, Green and Co.
39 Paternoster Row, London
Fourth Avenue & 30th Street, New York
Bombay, Calcutta, and Madras

(Tekstiin lisätty kappaleita lukemisen helpottamiseksi. // Some paragraphs added to the original text for making reading easier.)

Kaikki kuvat (kemialliset kaavat) puuttuvat // None of the illustrations (of chemical formulas) included.

Chay Root or Chay-aver (from chaya = which fixes colours, and ver = root), also called Indian madder, is the root of Oldenlandia umbellata (Linn.), Rubiaceæ. It bears the following Indian vernacular names: turbuli (Bengali); cheri-vello (Telugu), ché or chay, sayawer, imburel (Tamil). The plant is a small bush or herb found on sandy soils, chiefly near the sea-coast. It occurs in North Burma and Ceylon, but is most abundant in certain tracts of the Madras Presidency, from Orissa southward. It does not appear to be used in Bengal, but on the Malabar and Coromandel coasts, especially the latter, it is or was extensively cultivated, and employed in dyeing a colour analogous to Turkey-red. The chief market is Madras, where it was sold in small bundles at about 4d. a lb. The roots are usually about 10-12 inches long and ¼ inch thick, somewhat straight and stiff, tough and wiry, and with few or no lateral fibres. When freshly gathered, they have an orange colour; but when dried and kept, they assume a yellowish-grey hue. Boiling water gives merely a pale yellow extract, but if alkali is added, a blood-red decoction is soon obtained. The colouring principles seem to reside chiefly, if not entirely, in the bark of the root.

The older literature connected with chay root is extremely meagre, and is for the most part contained in the following publications: "Philosophy of Permanent Colours," 2282, 1813, Bancroft; "Bulletin de la Societe industrielle de Mulhouse," 5302, 1832, E. Schwartz and D. Koechlin; "L'Art de la Teinture des Laines," 475, 1849, Gonfreville. Quantities of the root were imported into Europe in 1774 and at later periods, and its dyeing properties were examined by the abovementioned experts. It met with little practical application, however, as it was not found to possess any advantage over madder; indeed, it was considered to have but one-half or even a fourth of the colouring power of madder; further, it was found to contain certain undefined yellow substances of an acid character, which interfered somewhat with its dyeing power. Still, it was recognised as a good dyestuff, giving the usual madder colours, and equally fast to soap. It is evident that the yellow substances referred to are not the same as those described in this chapter, as Schwartz states that they were present in larger quantity in "nona" (Morinda citrifolia) than in chay root, whereas the yellow substances described later exist in much larger quantity in chay root than in morinda root. Very probably they refer to Rochleder's "rubichloric acid," as this is contained in morinda root in larger amount than in chay root. Schützenberger, in his "Traite des matieres colorantes," 2, 291, 1867, states that he found chay root to contain alizarin and chlorogenin (rubichloric acid) and that it was easy to exhaust the root by extraction with alcohol.

In many respects chay root resembles madder, as both contain ruberythric acid, alizarin, rubichloric acid, and cane sugar, but there are very marked differences in the nature of the other constituents of the two roots. Madder, as is well known, contains purpurin, purpurin- and purpuroxanthin-carboxylic acids, etc., and but traces of yellow crystalline substances, forming barium compounds soluble in water, which have not been fully investigated. In chay root the former substances are entirely absent, but, on the other hand, although the root contains considerable quantities of yellow crystalline substances, they are quite distinct from those contained in madder.


Dyeing properties.

Although chay root contains acid principles which tend to dissolve the mordants, its employment as a dyestuff presents no difficulty. The only precautions necessary to be observed are to add 2 per cent, of chalk to the dye-bath, and to raise the temperature gradually to the boiling-point.

Dyeing experiments on ordinary stripe-printed calico, containing alumina and iron mordants, have shown that the dyeing power of chay root is equivalent to the presence of a percentage of 0,33-0,35 alizarin. Compared with ground madder root of good quality, it seems to have about half its dyeing power when the comparison is made before soaping, but after soaping it appears to be quite equal to madder. The reds, pinks, and chocolates have a distinctly bluer shade than those given by madder, and the lilacs are much fuller and brighter and very similar to those obtained from alizarin. This last feature alone ought to have secured a ready market for chay root among the European dyers, previous to the introduction of artificial alizarin, and it is somewhat strange that its marked suitability for lilacs should have escaped the observation of those who formerly made dyeing experiments with this root.

On oil-prepared calico, mordanted with alumina, chay root gives an excellent blue shade of Turkey- red, withstanding the operation of clearing with soap and stannous chloride better even than a madderdyed red, and quite equal to one obtained by means of artificial alizarin. Good brown, red, orange, and purple colours are readily obtained on wool, and also on silk, suitably mordanted with chromium, aluminium, tin, and iron, according to the ordinary method usual with dyers. On wool, the colours not being submitted to any soaping operation, chay root appears to possess about half the dyeing power of madder.

Boiled with dilute sulphuric acid, chay root yields a "garancine" of a very dark green colour and possessing about three times the dyeing power of the original root.


A. G. Perkin and J. J. Hummel, Chem. Soc. Trans., 1893, 63, 1160
ibid., 1895, 817
A. G. Perkin, ibid., 1907, 91, 2066
J. J. Hummel and A. G. Perkin, J. Soc. Chem. Ind., 1894, 13. 346.

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