Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by function]
6. colorant (material)
7. [colorant for dye and pigment]

Anotations

Scope note:

Synthetic colorant made from anthranilic acid and chemically identical to natural indigo. Synthetic indigo was first produced in 1880 by Adolf von Baeyer. It has almost entirely replaced the natural dyestuff.