332 CHEMICAL DISCOVERY AND INVENTION 



MODERN OR SYNTHETIC DYES 



Class I. Dyes with a basic character. These colours are 

 applied directly to wool and silk. They are fixed on cotton by 

 means of an acidic mordant. 



Mauve discovered 1856 



Magenta 1860 



Bismarck Brown 1865 



Chrysoidine ,, 1875 



Methylene Blue 1876 



Malachite Green ,, 1878 



Victoria Blue ,, 1883 



Auramine Yellow 



Class II. Dyes with an acidic character. These colours are 

 applied directly to wool and silk from an acid bath. 



Picric acid discovered 1771 



applied 1855 



Aniline Blue discovered 1862 

 Azo-scarlets ,, 1876 



Naphthol Yellow 1879 



Acid Green ,, ,, 



Tartrazine Yellow 1884 



Wool Blacks 1885 



Acid Magenta 1887 



Class III. Acidic dyes requiring a metallic mordant. These 

 dyes are fixed to mordanted fabrics, the colour produced being 

 due to an insoluble salt. (Dy e+ mordant = lake.) 



Alizarin Red discovered 1868 



and other dyes of the alizarin group, including Alizarin Blue and 

 Alizarin Green, Gambine Yellow, and certain other Azo-dyes. 



Quinone-oxime Dyes discovered 1875 



Class IV. Dyes with a saline character. Colours dyeing un- 

 mordanted cotton or linen directly in neutral or alkaline baths. 



Congo Red Series discovered 1884 



Primulin 1887 



Cotton Black (Diamine Black) 1889 



Chlorazol Blue 1898 



