In Britain, the Dyestuffs (Import Regulation) Act of 1920 had conme into force on 15 January 1921. This cut off many German products in an attempt to promote their production in Britain. However, British dye-makers needed German assistance to control several important markets. The British Dyestuffs Corporation and the Germans immediately began discussions over cooperation in dyestuffs and other sectors, and market division. Despite opposition from British professional chemists, many industrialists, and members of Parliament, negotiations were revived in 1927. ICI was anxious to retain the Empire market, and also to acquire control of Clayton Aniline, then in Swiss hands. The link up did not materialize, partially as a result of government pressure. In 1927, also, the British government introduced a tariff of 33 1/3 on imported synthetic organic products.
Aniline became popular as a mourning color, and the era eventually earned the moniker the Mauve Decade. However, the 19th century’s contributions to color were far from over.
reaction between Aniline, an Amine, acting as the Nucleophile, ..
The study of coal tar products that transformed the world of dye-making was spearheaded by August Wilhelm Hofmann, an assistant of Liebig. During the early 1840s, Hofmann demonstrated the identity of a basic compound obtained from various sources, including indigo and coal tar. It was soon named aniline from anil, the Arabic for indigo. After 1845 Hofmann and others prepared this aromatic amino compound in two steps from the coal tar hydrocarbon benzene. There were other coal tar hydrocarbons, such as toluene, naphthalene and anthracene. These were studied because their amino compounds appeared to be related to the alkaloids, above all the important drug quinine.
Consisting of a phenyl group attached to an amino group, ..
By 1864, the price of aniline red had fallen to about ten per cent of the 1860 levels, which reflected both the improved methods of large scale production and the high level of competition. A wide range of colors, including yellows, brown, and grey were available from commercial aniline.
The first azo dye was aniline yellow.
Since the Renards retained exclusive control over the production of aniline red, blue and violet, chemists in Paris and Lyon also sought out new reactions on coal tar products. In addition, the Renards, which became Societe La Fuchsine in 1864 (backed by the Credit Lyonnais bank), had problems with pollution from large scale arsenic acid oxidation (from around 1862). For these reasons, amino group hydrogens of aniline and toluidine were replaced by phenyl and alkyi groups prior to oxidation. This work, inspired by Hofmann’s publications on the constitutions of aniline colors, led to the introduction of reactions carried out at high pressures and temperatures by Poirrier in Paris (alkylation, 1866), which enabled the Renards’ patents to be circumvented. It also led to the introduction of less poisonous oxidants. In Britain, Levinstein and Holliday used the substitution reactions to bypass the blue and violet processes licensed to Simpson, Maule & Nicholson.
Aniline Yellow | C12H11N3 | ChemSpider
In 1864 Charles Lauth in Paris came out with the first of the improvements that were to make aniline black printing possible with machinery. This was through the use of insoluble copper salts. For the remainder of the nineteenth century, aniline black printing and dyeing was carried out on a vast scale.
While we call the modern chemical dyes we use aniline dyes, ..
I. Basic Dyes.The basic dyes are salts. usually hydrochlorides of coloured bases containing amino or substituted amino-groups, such as etc. They dye animal materials wool, silk, leather, feathers, etc.directly from a neutral bath, but possess for vegetable fibres, jute excepted, only a small affinity. They are applied to cotton and linen by mordanting these fibres with tannin and a metallic salt, such as a salt of anti mony, which produce insoluble compounds with the dye base. In calico printing, for which dye-stuffs of the basic class find their chief application, a thickened mixture of the dye-stuff with acetic acid and tannin is printed upon the cotton. This is then steamed to drive off acetic acid, leaving the insoluble dye tannate, the fixation of which is completed by passing through a bath of anti mony potassium tartrate. The basic dyes can be applied to jute, hemp and cocoanut fibre without a mordant and are frequently used for dyeing these materials. Some are used for lake pigments for wall-paper printing, while the salts of certain dye bases with the higher fatty acids, oleic, linoleic, stearic or resin acids, are used for colouring oils, varnishes, etc.