Fustic, also known as Cuba wood and yellow wood, is obtained from the Morus tint Soria, a tree growing in the West Indies, Central America and tropical South America. The best quality comes from Cuba and Mexico. The i wood is marketed in chips or ground, and an extract also is prepared which is sometimes re duced to a soft paste or solid form — often adulterated with glucose and quercitron. Fustic yields to two color principles, 'florin and maclurin, and gives bright yellow with an alum mordant, olive yellow with chrome and bright orange-yellow with tin. It is used more on wool than on cotton. At its best it is not fast to light. Its largest use is with logwood to produce a dead black and with cutch to produce catechu shades.
Indigo is obtained by fermentative steeping of the stems and foliage of several species of the Indigofera family, and to a less extent of some others. Its characteristic blue color prin ciple is indigotin, but indigo contains also an other dye principle, indirubin or indigo red. It is used very extensively in dyeing both wool and cotton, and is employed also as a Thottomp for compound shades— olives, browns and blacks. Indigo extracts are produced by the action of sulphuric acid on indigo. They are, chemically, indigotin sulpho-acids, and are freely soluble in water, and dye wool with rapidity, and a brighter color than ordinary indigo; but the color fades on exposure to light.
Logwood or Campeachy wood is the prod uct of the large and rapidly growing tree, Thrmatoxylon Campechianum, a native of tropi cal and subtropical America, Cuba, Haiti and the West Indies. The best qualities now come from Jamaica and Honduras, the Campeche (Mexico) supply being practically exhausted. Logwood is white in color when first cut, the brown-red hue being developed by exposure to the air. It is marketed in the form of a concentrated extract made from the chips or raspings after ageing and fermenting. The coloring principle is halnatein. It is used in the dyeing of silk, as it renders the fibre opaque, a quality lacking in coal-tar dyes. It is employed also in the production of cheap blacks on wool and cotton. On wool it is used with a chrome mordant, producing a bluisb-black, and with a tin mordant, producing a violet tone. In con junction with other dyes it produces blues, greens, olives and browns.
Madder, as marketed, is the ground cortex of the root of the madder plant, Rubio tint- torum, a native of Asia Minor. It has been cul tivated many years in Italy, France and Hol land. It yields the dye principles, alizarin, pur
purin, pseudo-purpurin, xanthin and chlorogenin. Madder is used in dyeing woolen cloth and carpet yarns, but for few other purposes. With chromium it gives bluish-red to crimson; with iron, reddish-brown to maroon ; with aluminum, scarlet to pink; with copper, yellow-brown; with tin, reddish-orange.
Persian Berries are the dried fruits of several species of Rhamnus (buckthorn) growing wild in Asia Minor. They are also cultivated in southern Europe and the East. They yield two color principles, rhamnetin and rhamnazin. They are used chiefly in printing cotton fabrics, with aluminum mordant for bright yellow, tin mordant for orange and chromium mordant for brown. With cochineal, they produce orange and scarlet, giving redder and deeper shades than fustic or quercitron —but at increased cost.
Quercitron is the inner bark of the Quercus tinctoria, an oak native to America, and grow ing in large numbers in Pennsylvania and the South Atlantic States. It appears in commerce as the ground bark, and its extract. It con tains two color principles, quercetin and quer citrin. A purified or concentrated dry extract in powdered form has the trade name of Quercitron imparts a bright yellow to wool and mordanted cotton and silk. With cochineal it produces bright orange shades, and with logwood gives blacks. With aluminum it produces greenish yellow; with chromium, dull yellow; with tin, bright orange; and with iron, olive to greenish black.
Robinia, a new natural dyestuff, was dis covered in 1915, in the Yellow Locust, Robinia pseudacacia. The extract is similar to that of quercitron. It is still in the experimental stage.
Safflower, the dried flower head of Cartha mus tinctoria, cultivated in India and Egypt. Its active principle is carthamin, which produces shades of pink on bleached cotton. The color is not fast either to light or the laundry.
or Sandalwood, see Cans wood.
Turmeric or Indian Saffron, is the ground root of the Curcuma tinctoria, a plant growing abundantly in China and the East Indies. The coloring principle is known as curcumin, and dissolves out of the turmeric freely with alcohol, and less freely with hot water. It imparts yellow to cotton, wool and silk, but is used prin cipally in combination, as its color is not fast. Although mordants are not necessary, their use produces modified shades of yellow, orange and olive.