The Art of Dyeing - No. 16.

Scientific American 31, 14.4.1855

Purple on Wool. - The process of woolen dyeing differs from the silk process n a very simple but very important point, viz., in boiling the former, whereas silk is never boiled. This is the grand and leading distinction between silk and woolen dyeing.

Common purple is dyed on woolen goods with logwood, muriate of tin, alum, and tartar - all oiled together in a clean copper kettle. About four pounds of logwood will dye ten pounds of wool; this requires six ounces of tartar, six of the muriate of tin, and three of alum. The logwoods for purples sould be boiled and left to settle for a few days, in a large cask before it is used. Dyers generally keep a large cask of boiled logwood always on hand. Two such casks should be kept in every dye-house, so as to fill up one and allow its contents to be settling while the other is being used. A brownish color is ectracted from chip logwood, which injures the peculiar shade of purple. When the alum and tartar are dissolved in the kettle, the logwood liquor is put in, and suffered to boil for five minutes, when the goods are then entered and boiled for three-fourths of an hour, then lifted, washed and dried.

Cochnineal Purple. This color is imparted to wool by dyeing it first a light red as described on page 146, then washing and bluing on the top with cudbear in a clean boiler, at a scalding hat - about two ounces of cudbear to the pound of goods. Urine or liquid ammonia is used in the boiler to extract the cudbear color, and impart it to the goods. This is a very rich and beautiful color.

Various shades of puce and lavender are dyed on wool, by dyeing the goods a cochineal red or pink, and bluing on the top with suplhate of indigo (chemic) in a clean vessel.

Ruby. - This color may be dyed on wool with cudbear and ammonia. Two pounds of cudbear and a gill of aqua ammonia, will dye ten pounds of wool.

Wine Color, Chrome. - By preparing woollen goods by boiling them in the bichromate of potash - two ounces to the pound of goods - then finishing in a clean kettle with half a pound of cudbear, and a very little logwood liquor, a good wine color will be produced.

The same process for dyeing wool will dye woolen yarn, worsted, cloth, and every fabric made of wool. Some authors on dyeing divide these kinds of goods into classes, and give different receipts (prescribing different substances.) This is all nonsense. The same stuffs will dye the same colors on all, but not with the same uantity of them, in this consists the difference. Wool requires about one-sixth more dye-stuffs than yarn, and nearly one half more than fine cloth. coarse wool requires about one-fourth more dye stuffs than fine wool.

Purple, puce, ruby, &c., can be dyed on goods having a red lac base, as well as on those with a cochineal red base.

Peachwood Purple. - This color is dyed with peachwood, logwood, and alum. About half a pound of peachwood, two ounces of logwood, and one of alum, will dye a pound of wool. These are all boiled together, (goods and stuffs) for an hour. The old plan was to prepare the goods in an alum mordant first, then to dye in a clean kettle. This color can be blued down to a wine shade, with urine, in warm water.

Claret Color. - This is a deep purple inclining to a brownish shade. It is dyed by giving the goods about double the quantity of logwood, as the common purple, and adding one pound of peachwood for every ten pounds of goods.

Camwood Claret. - This color is dyed with camwood, by using about ten pounds of the camwood, to ten pounds of wool, and half a pound of logwood. It is darkened to the shade desired (after the goods have been boiled for an hour and lifted) wth the sulphate of iron. Great care is required in the use of the iron, as the goods are liable to be spotted. To make the iron (usually called saddening) work level, a little sumac is added to the camwood, and the froth skimmed off the boiler, before the goods are entered. This color will stand exposure to the sun. None of the spirit clarets do this. The beautiful wine colored broadcloth which has been noticed to become of a greenish color by exposure, on the shoulders of gentleman's coats, is dyed by the process described above for common purple. No mordant is used for camwood claret. Every shade of claret can be dyed with redwood, logwood, and alum, at one dip. The redwood may be common hypernic or Brazil wood. It is difficult to give the exact weight of dyestuffs for a particular shade of color because there is such a difference in the quality of dye stuffs, and in the quality of goods, all of which make a great difference to the dyer. All that can be said on this head, is to tell what stuffs, and about the quantities that will dye a certain color, and by using less or more these stuffs, so will the shades be lighter or darker.

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