Category:Coal tar

Coal" tar`.

Defn: A thick, black, tarry liquid, obtained by the distillation of bituminous coal in the manufacture of illuminating gas; used for making printer's ink, black varnish, etc. It is a complex mixture from which many substances have been obtained, especially hydrocarbons of the benzene or aromatic series.

Note: Among its important ingredients are benzene, aniline, phenol, naphtalene, anthracene, etc., which are respectively typical of many dye stuffs, as the aniline dyes, the phthaleïns, indigo, alizarin, and many flavoring extracts whose artificial production is a matter of great commercial importance.