For 10 lbs. cotton boil 3 lbs. Sumach, let the cotton steep in this over night: wring out and work in red spirits (1 gill to a gallon of water). Wring out and wash well. Boil up 3 lbs. limawood (or Brazil or Peach wood) and 1 lb. fustic. Work the cotton in this ½ hour, as warm as the hand can bear; add 1 gill red spirits and work 15 minutes longer. Wash.
CHAPTER VIII.
YELLOW.
WELD. OLD FUSTIC. TURMERIC. QUERCITRON. DYER'S BROOM. HEATHER, AND OTHER YELLOW DYES.
"There are ten species of drugs for dyeing yellow, but we find from experience that of these ten there are only five fit to be used for the good dye—viz. Weld, savory, green wood, yellow wood and fenugrec". "Weld or wold yields the truest yellow, and is generally preferred to all the others. Savory and green wood, being naturally greenish, are the best for the preparation of wool to be dyed green: the two others yield different shades yellow."—Hellot.
WELD
Weld, Reseda luteola, an annual plant growing in waste sandy places. The whole plant is used for dyeing except the root. It is the best and fastest of the yellow natural dyes.
Hellot's directions for dyeing with weld are the following:—"Allow 5 or 6 lbs. of weld to every pound of stuff: some enclose the weld in a clean woollen bag, to prevent it from mixing in the stuff; and to keep the bag down in the copper, they put on it a cross of heavy wood. Others hold it in the liquor till it has communicated all its colour, and till it falls to the bottom: the stuff is then suspended in a net, which falls into the liquor, but others, when it has boiled, take out the weld with a rake and throw it away."
The plant is gathered in June and July, it is then carefully dried in the shade and tied up into bundles. When needed for dyeing it is broken up into pieces or chopped finely, the roots being discarded and a decoction is made by boiling it up in water for about ¾ hour. It gives a bright yellow with alum and tartar as mordant. With chrome it yields an old gold shade; with tin it produces more orange coloured yellows; with copper and iron, olive shades. The quantity of weld used must be determined by the depth of colour required. The dye bath is prepared just before dyeing, the chopped weld being put into weighted bags and boiled in soft water for ½ to 1 hour. 2% of Stannous chloride added to the mordant gives brilliancy and fastness to the colour. Bright and fast orange yellows are got by mordanting with 8% Stannous chloride instead of alum. With 6% copper sulphate and 8% chalk, weld gives a good orange yellow. Wool mordanted with 4% of ferrous sulphate and 10% tartar and dyed in a separate bath with weld with 8% chalk, takes a good olive yellow. 8% of alum is often used for mordant for weld. The dye bath should not be above 90°C. It is good to add a little chalk to the dye bath as it makes the colour more intense, while common salt makes the colour richer and deeper.
"Woollen dyers frequently add a little stale urine or lime and potash to the water in which it is boiled. They commonly employ 3 or 4 oz. of alum and one of tartar for each pound of the wool. Tartar is supposed to render the yellow colour a little more clear and lively."—Bancroft.
Weld is of greater antiquity than most, if not all other natural yellow dyes. It is cultivated for dyeing in France, Germany and Italy. It is important for the silk dyer, as it dyes silk with a fast colour. The silk is mordanted in the usual way with alum, washed and dyed in a separate bath of 20 to 40% weld, with a small quantity of soap added. After dyeing, the colour is brightened by working the silk for 10 minutes in a fresh soap bath with a little weld added to it. Wring out without washing.
Recipes for Dyeing with Weld.