The Art of Dyeing - No. 3. Red Color on Cotton.

Scientific American 18, 13.1.1855

Red Color on Cotton - This color is temed the "calorific ray," and imparts a cheerful aspect to rooms looking to the north. It is a striking and gaudy color, by some called vulgar, but it is wrong to apply such a term to any color.

A common red color is dyed on a cotton, with two different kinds of vegetable dyewoods, namely, peachwood and barwood. The latter makes a more permanent color than the former. The cotton being boiled and prepared for opetarion, is first steeped for about eight or ten hours in a string decoction of sumac - about three pounds to the ten pounds of cotton, either in yarn or the piece. The goods must never be crowded too close in the vessels in which they are steeped, and no part of them should be suffered to rise above the liquor. This preparation is the same for both kinds of dyewoods. After the goods are lifted out of the sumac (if yarn, they are wrung, if pieces, they are suffered to drip well,) and then entered into the "spirit tub." This is a standing tub of the nitro murate of tin, described on the page 130; in which they receive five turns or handlings, and are then sunk under the liquor for about one hour and a half. They are then lifted, suffered to drip for a few minutes, wrung (if yarn,) and afterwards washed in clean water. If for bar-wood, great care must be exercised that no free acid is left in them; this can easily be detected by tasting them - the usual way. It requires about one pound of bar-wood to color one pound of cotton, and this is always done in a boiler bath. The yarn is wrung up, when washed out of the spirits, or if pieces, they are well dripped and run upon a winch. The bath should be a long rectangular copper kettle for yarn, if heated with a fire underneath, or it should be a water-tight long wooden box if heated with steam. The bar-wood is fisrt introduced, and allowed to boil for about fifteen minutes, then it is put off the boil with a pailfull of cold water, and the goods are entered and handled well over pins, or the winch, for about a quarter of an hour, when the liquor is brought to the boil and kept boiling for half an hour, when the goods will have attained to a good full color. Some enter the goods into the bar-wood liquor when cold, and bring it gradually up to the boil in half an hour, and keep it at this heat for half an hour longer. If the goods are to be dyed with peach wood, about six pounds are used for every ten of the goods. This wood is simply boiled for about fifteen minutes (if finely ground,) then put off the boil, and the clear liquor lifted out into a tub or tubs and equally divided for the quantity of goods to be dyed. The goods are then entered and handled quickly for fifteen minutes, then lifted, and about a small tea cupfull of spirits from the standing tub is added to the liquor., and well stirred. The goods are then re-entered, handled for ten minutes, and being raised, as it is termed, are then lfited,washed, and wrung for drying. Bar-wood reds require much washing if the goods are boiled in the liquor; peach-wood reds require but little washing. Some add two pounds of cam-wood to every eight of bar-wood, but use so much less of the latter dye wood. - Unless the bar-wood is good, and it is easy to deceive the eye with its appearance, a good full color cannot be produced.

Madder is employed for dyeing two kinds of reds on cotton, one a dull brownish red called "indian," and another the most brilliant of all, "named Turkey red." The former is dyed by preparing cottong with a very light sumac, one pound to ten of cotton in yarn, in the same way as for bar-wood red; then giving it a strong mordant of the acetate of alum. This latter is prepared by dissolving one pound of alum for every ten pounds of cotton, to be dyed in a clean vessel, then adding, in a dissolved state, one ounce of the acetate of lead, stirring all up, and allowing the sediment to fall to the bottom. The clear is then used as a mordant, at a temperature of 160°. The goods are handled in this for about ten minutes, then sunk under the liquor for six hours, after which they are lifted, dripped, and washed thoroughly. They are then fit to receive the madder dye. This is done in a copper kettle gradually brought up to a boil, and then boiled for half an hour. It takes about 1½ pounds of ground madder roots to dye one pound of cotton (a little sumac is added to the madder). This is an expensive color but very fast. No Turkey reds are dyed in our country; the process is tedious and expensive, and it would perhaps be a waste of space to describe it. A description of the process is to be found in Dr. Ure's old Chemical Dictionary, furnished by M. Papillon, the French gentleman who introduced the art into Britain, but the whole details of the process, as now practiced by the best Turkey-red dyers, is totally different, and the manipulations are much reduced in number.

Madder is the best vegetable coloring matter yet discovered for dyeing red, and were it more generally cultivated in our country, so as to reduce its price, and were the advice of Mr. Partridge, as given in former numbers of the Scientific American, followed, our country might soon rival, if nor surpass, all others in dyeing red colors on cotton. As it is, Scotland supplies us with Turkey red yarn and plain red pieces, and France (if we are not imposed upon,) with Turkey red calicoes. Speaking correctly, Turkey-red is the only pure red dyed on cotton, all the other reds - bar-wood and peach-wood - are dull and brownish when compared with it.

Alizarin is the red coloring matter od madder. Garancine is a product of madder, obtained by submitting it (the madder) for a short time to strong sulphuric acid, washing the latter well out, and then drying the madder so treated for market. Alum is the mordant used for this substance, which only yields its color at a boiling temperature. A little sumac is added in the bath, and the process is about the same as for Indian madder red. We believe its use is confined to calico print works entirely. It gives a more lively color than common madder, and it is not so liable to run upon the white parts of calicoes. Colorine is another product of madder, now extensively used in French calico printworks.

Brazil wood and sapan wood are used for dyeing red in the same manner as peachwood (Nicaragua). They are finer in quality, and superior, but not much used because they are dearer. None of the stand exposure to the sun for any lenght of time, hence they are set down as fugitive colors.

In out next we will describe the modes of coloring silk and wool, red.

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