Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by function]
6. additive (material)

Anotations

Scope note:

Treatment added to laundered fabrics to make them softer. Historical softeners were typically based on water emulsion of soap and oils. Contemporary softeners are primarily based on quaternary ammonium salts.