BROWN DYE

Upon this subject some general views are given in the article Dyeing , explanatory of the nature of this colour, to which I may in the first place refer. This dye presents a vast variety of tints, from yellow and red to black brown, and is produced either by mixtures of red, yellow, and blue with each other, or of yellow or red with black, or by substantive colours, such as catechu or oxide of manganese, alone. We shall here notice only the principal shades; leaving their modifications to the caprice or skill of the dyer. 1. Brown from mixture of other colours. Wool and woollen cloths must be boiled with one eighth their weight of alum and sulpho-tartrate of iron (see this article); afterwards washed, and winced through the madder bath, which dyes the portion of the stuff imbued with the alum red, and that with the salt of iron black; the tint depending upon the proportion of each, and the duration of the madder bath. alum, and one ounce of common salt, and then dyeing it in a bath of logwood containing either sulphotartrate, acetate, or sulphate of iron. Or the stuff may be boiled with alum and tartar, dyed up in a madder bath, and then run through a black bath of iron mordant and galls or sumach. Here the black tint is added to the red till the proper hue be hit. The brown may be produced also by adding some iron liquor to the madder bath, after the stuff has been dyed up in it with alum and tartar. A better brown of this kind is obtained by boiling every pound of wool with 2 ounces of alum, dyeing it up in cochineal, then changing the crimson thus given into brown, by turning the stuff through the bath after acetate of iron has been added to it. Instead of the cochineal, archil or cutbear, with a little galls or sumach, may be used. Wool or silk may also receive a light blue ground from the indigo vat, then be mordanted with alum, washed, and turned through a madder bath till the wished-for brown be brought out. For the deeper shades, galls or sumach may be added to the paler Brazil-wood, with more or le iron mordant. Instead of the indigo vat, Saxon blue may be employed to ground the stuff before dyeing it with madder, or 5 pounds of madder, with 1 pound of alum, a solution of one tenth of a pound of indigo in sulphuric acid, may be used with the proper quantity of water for 20 pounds of wool; for dark shades some iron mordant may be added. Or we may combine a bath of cochineal or cutbear, fustic, and galls, and add to it sulphate of iron and sulphate of indigo, blunted with a little potash. If we boil woollen cloth with alum and tartar, then pa it through a madder bath, and afterwards through one of weld or fustic, containing more or le iron mordant, we obtain shades variable, according to the proportions of the materials, from mordoré and cinnamon to chesnut brown. After the same manner, bronze colours may be obtained from the union of olive dyes with red. For 25 pounds of cloth, we take 4 pounds of fustic chips, boil them for 2 hours, turn the cloth in this bath for an hour, and drain it; then add to the bath from 4 to 6 ounces of sulphate of iron, and 1 pound of ordinary madder, or 2 pounds of sandal wood; put the cloth again in this compound bath, and turn it through, till the desired shade be obtained. By changing the proportions, and adding an iron mordant, other tints may be produced. This mode of dyeing is suitable for silk, but with three different baths, one of logwood, one of Brazil-wood, and one of fustic. The silk, after being boiled with soap, is to be alumed, and then dyed up in a bath compounded of these three decoctions, mixed in the requisite proportions. By the addition of walnut peels, sulphate of copper, and a little sulphate of iron, or by pa ing the silk through a bath of an not to, a variety of brown shades may be had. Or the silk may receive an an not to ground, and then be pa ed through a bath of logwood or Brazil-wood. For 10 pounds of silk, 6 ounces of an not to are to be taken, and di olved with 18 ounces of potashes in boiling water. The silk must be winced through this solution for 2 hours, then wrung out, dried, next alumed, pa ed through a bath of Brazil-wood, and finally through a bath of logwood containing some sulphate of iron. It is to be wrung out and dried. Brown of different shades is imparted to cotton and linen, by impregnating them with a mixed mordant of acetates of alumina and iron, and then dyeing them up, either with madder alone, or with madder and fustic. When the aluminous mordant predominates, the madder gives an amaranth tint. For horse-chesnut brown, the cotton must be galled, plunged into a black bath, then into a bath of sulphate of copper, next dyed up in a decoction of fustic, wrung out, pa ed through a strong madder bath, then through the sulphate of copper solution, and finished with a soap boil. Different shades of cinnamon are obtained, when cottons first dyed up with madder get an olive cast with iron liquor in a fustic bath. of weld and verdigris, pa ing them through a solution of sulphate of iron, wringing and drying them; next putting them through a bath containing 1 pound of galls for 10 pounds of stuff, again drying, next aluming, and madder ing. They must be brightened by a boil in soap water. the oiling proce of the Turkey red dye. Such stuffs must be galled, mordanted with alum (see Madder ), sulphate of iron, and acetate of lead (equal to 2 ⁄ 3 of the alum); after washing and drying, dyed in a madder bath, and cleared with a soap boil. The tint of brown varies with the proportion of alum and sulphate of iron. We perceive from these examples, in how many ways the browning of dyes may be modified, upon what principles they are founded, and how we have it in our power to turn the shade more or le towards red, black, yellow, blue, . fast brown of different shades, according to the concentration of the bath. The colour is more lively with the addition of alum. The decoction of bastard marjoram ( Origanum vulgare ) dyes cotton and linen a reddish brown, with acetate of alumina. Wool takes from it a dark brown. The bark of the mangrove tree ( Rizophora mangle ) affords to wool boiled with alum and tartar a fine red brown colour, which, with the addition of sulphate of iron, pa es into a fast chocolate. The Bablah , the pods of the East Indian Mimosa cineraria , and the African Mimosa nilotica , gives cotton a brown with acetate or sulphate of copper. The root of the white sea rose ( Nymphæa alba ) gives to cotton and wool beautiful shades of brown. A mordant of sulphate of iron and zinc is first given, and then the wool is turned through the decoction of the root, till the wished-for shade is obtained. The cotton must be mordanted with a mixture of the acetates of iron and zinc. Walnut peels ( Juglans regia ), when ripe, contain a dark brown dye stuff, which communicates a permanent colour to wool. The older the infusion or decoction of the peels, the better dye does it make. The stuff is dyed in the lukewarm bath, and needs no mordant, though it becomes brighter with alum. Or this dye may be combined with the madder or fustic bath, to give varieties of shade. For dyeing silk, this bath should be hardly lukewarm, for fear of causing inequality of colour. The peelings of horse-chesnuts may be used for the same purpose. With muriate of tin they give a bronze colour, and with acetate of lead a reddish brown. Catechu gives cotton a permanent brown dye, as also a bronze, and mordoré, when its solution in hot water is combined with acetate or sulphate of copper, or when the stuff is previously mordanted with the acetates of copper and alumina mixed, sometimes with a little iron liquor, rinsed, dried, and dyed up, the bath being at a boiling heat. Ferrocyanate of copper gives a yellow brown or a bronze to cotton and silk. to four ounces of verdigris, with five ounces of muriate of ammonia.—The bronze ( solitaire ) is given by pa ing the stuff through a solution of muriate or sulphate of manganese, with a little tartaric acid, drying, pa ing through a potash lye at 4° Baumé, brightening and fixing with solution of chloride of lime.