The Art of Dyeing - No. 1

Scientific American 16, 30.12.1854

Every nation - the most savage and civilized - have been acquainted with this art, in some measure, from the remotest ages of antiquity. Tyre was famous for coloring purple, and ancient India for cotton prints. - Among the modern nations, France, Germany, and Britain maintain a superior claim to an acquaintance with dyeing. The nature of this art consists in imparting to fabrics various colors, by the application of certain substances to them, in water baths. The art is a chemical one entirely; but little known to the professors of chemistry, as its secrets have been confined to the practical workman. It shall be out endeavor to reveal these in plain tems, so that all may understand them. We will conduct the subject in chapters relating to classes of colors, and will first commence with the primary colors, and will take "yellow" or the luminous ray first.

Yellow on Cotton. - All cotton yarn must be first boiled in clean water before it is dyed. It is first made up in bundles of ten pounds each, by tying a strong thread loosely round each hank, and strapping each bundle with two of its own hanks, to keep all from being entanglend when boiling. In some large dye shops, there are boilers which will hold 2000 pounds, or 200 ten pound bundles. These bundles are boiled for about three hours, until all the air is expelled from the minute cells of the cotton. The water is then run off, and the bundles put on straight sticks, about one inch in diameter and two feet long - six sticks for each ten pounds. The yarn is wrung on arms, called pegs, and scutched out evenly by the workmen. It requires practice to do this, and could no more be taught by words than blacksmithing.

Yellow can be dyed with various substances; the most common on cotton at the present time, is produced by the bi-chromate of potash and the acetate or nitrate of lead. To dye ten pounds of cotton yarn a good yellow, dissolve three ounces of the bi-chromate of potash in a small clean dish, and nine ounces of the acetate of lead in another, and then place about ten common pailsfull of clean milk-warm water into each of two separate tubs, and into each of two separate tubs, and into one pour the dissolved acetate of lead, and enter the yarn, giving each hank five turns, one after another, - over the pins, and then wring and scutch them out. Pour now the dissolved bi-chromate of potash into the other clean tub of water, and give the leaded yarn five like turns in this, when it will assume a beautiful yellow color. After every dip the yarn is aired in a frame, and is lastly run through the tub of acetate of lead, washed, wrung or pressed, and is ready to be dried. Any depth of shade can be produced by giving a number of dips to the yarn, wringing and airing after each dip. It is always best to give two dips to every shade, in order to make the color level. If the yarn was not finished out of the lead solution, it would dry in reddish spots.

Straw Colors are produced on cotton yarn by first bleaching the yarn, washing it well, and treating it as for yellow, only giving less dye stuff. One ounce of the bichromate of potash will dye ten pounds of yarn this shade. Three ounces of the acetate of lead are required as a mordant for every ounce of the bi-chromate of potash that is used as a dye. The nitrate of lead is employed for deep shades of yellow; it gives the yarn a rich reddish tint; the acetate of lead produced a lemon tinted yellow. If some dissolved sulphate of zinc is employed (about one ounce to the ten pounds of yarn,) in a clean tub of water, after the last leading, and the cotton run through this, giving five turns, the color is rendered more permanent.

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