Animalization of Vegetable Fabrics.

Scientific American 19, 8.5.1869

In the older theories of dyeing, it was held tha[t] the animal tissues of wool and silk absorbed and retained colors more readily than the vegetable tissues of cotton and linen, by virtue of some peculiar animal substance they contained. As a a consequence of this theory, attempts were made to communicate some animal principles to vegetable fabrics, with a view to improving their powers of receiving colors. The use of cow dung in dyeing madder goods; the use of sheep's dung and bullocks' blood, and urine in turkey-red dyeing, were explained, upon the supposition that they animalized the fabric in some way or other. The present view of animalization is, that it is not possible to animalize a fabric in any other way than by actually depositing upon it the animal matter in question, and that any increased facility for taking colors thus communicated, is effected by the animal matter itself held on the fabric, and not by any new property of the fabric itself. Thus, if a piece of calico is steeped in a solution of albumen, dried, and then steamed or plunged into boiling water, the albumen is fastened upon the cloth, and such cloth is then capable of receiving colors from picric acid, sulphate of indigo, magenta, archil, and other coloring matters, which previously had no affinity for the cloth. But it is impossible to look upon the albumen in any other light than as a kind of mordant acting as an intermediary between the color and the calico, differing, however, from ordinary mordants in some essential particulars. Beside albumen, the animal matters called casine and lactarine, possess similar properties, and have been tried on a large scale, but without any marked success, as mordants or bases for some of the colors, which are not attracted by the ordinary metallic mordants. The increased affinity for colors given to calico by oil, could not correctly, under any view, be called animalization, since the oils are all vegetable oils; but in fact there appears to be a considerable analogy between this case of mordanting and that by coagulable animal matters.

— Dictionary of Dyeing and Calico Printing.

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