[15] This preparation is made by adding 3 libs. of sal ammoniac to 1 gallon of solution of tin (see [Scarlet Dye], and [Tin]), evaporating, and crystallizing. The sal ammoniac seems to counteract the separation of the tin by peroxidizement.
Cochineal pink.—Acetate of alumina is mixed with decoction of cochineal, a little tartaric acid and solution of tin; then thickened with starch, dried, and steamed.
Steam brown.—A mixed infusion of logwood, cochineal, and Persian berries, with cream of tartar, alum (or acetate of alumina), and a little tartaric acid, thickened, dried, and steamed.
Green, blue, chocolate, with white ground, by steam.—Prussiate of potash and tartaric acid, thickened, for the blue; the same mixture with berry-liquor and acetate of alumina, thickened, for the green; extract of logwood with acetate of alumina and cream of tartar, thickened, for the chocolate. These three topical colours are applied at once by the three-colour cylinder machine; dried and steamed. Though greens are fixed by the steam, their colour is much improved by passing the cloth through solution of bichromate of potash.
In France, solution of tin is much used for steam colours.
VIII. Spirit or Fancy colours.—These all owe their vivacity, as well as the moderate degree of permanency they possess, to their tin mordant. After printing-on the topical colour, the goods must be dried at a gentle heat, and passed merely through the rinsing machine. Purple, brown, or chocolate, red, green, yellow, blue, and white discharge; any five of these are printed on at once by the five-colour cylinder machine. See [Rinsing Machine].
Chocolate, is given by extract of Brazil-wood, extract of logwood, nitromuriate of tin, with a little nitrate of copper; all mixed, thickened, and merely printed-on.
Red, by extract of Brazil-wood and tin, with a little nitrate of copper.
Green, by prussiate of potash, with muriate of tin and acetate of lead, dissolved, thickened, and printed-on.
The goods after rinsing must be passed through solution of bichromate of potash, to convert the Prussian blue colour into green, by the formation of chrome yellow upon it.