ANILINE YELLOWS.-Ill 1864, Simpson, Maule, and Nicholson offered a yellow dye stuff under the name of " Aniline Yellow," which is an oxalate of the produet obtained by the aetion of nitrous acid on aniline (ace Amido-azo-benzol). Aniline is dissolved in three timea its weight of aleohol, and nitrous acid is paased into the solution until the liquid becomes deep red; thia is afterwards raised with a large excess of slightly dilute hydrochloric acid, to separate the eolouring matter ; the crystalline product is filtered, washed with very weak alcohol, and boiled several times in water ; the solution is mixed with ammonia, and the product is purified by recrystallization ; its solution in aleohol is used for dyeing. By heating the aeid, a shade between garnet-red and brown is produced.
Schiff's yellow is met with in eommerce as a paste ; dissolved in weak acids, it dyes a yellow, which is rendered more solid by passing through a solution of carbonate of soda ; 3 parts stannate soda, 1 nitrate aniline, in 10 of water to which a little carbonate soda is added, are heated to 100° (212° F.) ; a strong reaction sets in ; as soon as acids produce a red coloration, the procesa is
eomplete. On adding strong hydroehloric aeid, the colour is deposited as a resinous mass.
Zinaline.—This is obtained by acting with nitrous acid on solutions of. rosaniline, Hofmann's and ordinary violets, Usebe's green, and Girard's aniline brown. Different tints are developed according to the amount of gas passed through, the highest shade being a yelloatish red. Evapo ration in a salt-water bath produces a red powder. Its solution in alcohol with a little ammonia gives, on silk and wool, bright shades of orange. With indigo-dyed goods it gives a green.
Sopp's yellow, or jaune de Lyon.—(See Cerise).