Explanatory notes
… (1) Nitroso or nitro compounds. (2) Mono- or polyazo compounds. (3) Stilbenes. (4) Thiazoles (e.g., … thioflavine). (5) Carbazoles. (6) Quinoneimines, e.g., azines (indulines, nigrosines, eurhodines, safranines, … not used for their dyeing properties are excluded , e.g., azulenes ( heading 29.02 ); trinitrophenol (picric acid) and …