Purple on silk.
This color on fine wool was the most famous in ancient times, and the city of Tyre was distinguished for dyeing it. It was a badge of power and wealth, as monarchs and rich men only could buy it. It woe, however, somewhat different from what is now known by the name of purple, it being a deep crimson, like clotted blood, while the modern purple is a blue tinged with red. It is dyed on silk in the plum vat, just in the same manner as upon cotton, and as described on page 218. All the shades of lavender can also be done in the same manner the plum colors on cotton. But there are other methods of dyeing purple on silk, very different from the processes of cotton dyeing.
Alum Purple.
This is the most simple method of dyeing purple on silk. It consists in preparing the silk in an alum tub or mordant, at about 3° Twad., for an hour, then dripping them, and washing in two tubs of clean water, after which they are handled in hot logwood liquor (about 5 lbs. of dyewood to ten of silk) for half an hour, and lifted.
Into the logwood liquor about a wine glassful of the muriate of tin is added for every ten pounds, the liquor stirred up, and the goods again catered. Five turns will finish, when they may he lifted up, washed, and made ready for drying. The redder the shade desired, the more spirits are added for railing. The old plan of dyeing simple logwood purple on silk, was to use spirits, cream of tartar, and logwood all together, heated up in a copper kettle to a sealding heat, and handle in this till the color was full. It is not to sure, cheap, nor quick a method as to use an alum mordant, the logwood by itself, and then raise with the spirits.
Cochineal Purple.
A beautiful purple can be dyed on silk by dyeing a good cochineal red on it, as described on page 154, then bluing on the top, by a bath of cudbear and pure liquid ammonia. Dyers use urine in place of pure ammonia, for cheapness. One pound of cudbear will answer for ten pounds of goods. The ammonia must be pretty strong, and the goods handled at a good heat until the desired shade is obtained. This is a very rich color, but expensive. The goods must be well washed before they are dried.
Peach Blossom Color.
This color it dyed on silk with cudbear and ammonia liquid, or urine. The quantity of cudbear must just be proportioned to the depth of shade desired. Four ounces will color one pound of silk a full shade.
Archil Shades.
Beautiful shades, between a ruby and purple, are dyed with archil.
They are dyed at one dip, in liquor kept at a scalding heat. Neither cudbear nor archil colors are fast, although they will stand washing in cold soap suds. By exposure to the sun and air, they soon fade and become rusty.
Claret.
This color is simply a deep purple. It is dyed by preparing the silk in an alum mordant, as for simple purple, dyeing a good full red with peachwood on it, and then darkening with logwood to the desired shade. The logwood should never be added until the goods have obtained a deep red color. It has been discovered, that it takes twice as much peachwood to produce the same effect when the logwood is given before the peechwood, as afterwards.
Maroon.
This is simply a peachwood red slightly darkened by adding a little logwood to the red liquor. To make a rich maroon, and a rich claret, a full red is positively necessary, as the base of the color. Brazil wood is more economical for use than common hypernie wood, although the price is higher. It yields a greater quantity of, and a superior color.
Lilac.
A very simple lilac can be colored by preparing the silk in alum for about twenty minutes,then giving a very weak logwood liquor. All shades of lilac, however, can be colored with archil and cudbear. The goods must be white for all these colors, except claret.
The purples that are dyed in the plum tub may be blued deep, by running them afterwards through a dilute solution of chemic (sulphate of indigo).
Archil and Cudbear.
These dye drugs are made from the lichen rocella, a species of sea weed. The best comes from the Cape de Verd Islands, but it is found in many other countries. It is steeped for about a smooth in a close cask, in a solution of urine, when it ferments, after which it may be used, and in this state is called "archil." Cudbear is a powder of these lichens. Archil and cudbear colors require no mordant. Many experiments have been tried with archil in order to color cotton with it, but hitherto they have all proved abortive. If it could be dyed on cotton, and rendered permanent, it would be a grand triumph for practical chemistry.
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