This ingredient helps incorporate mica in bath bombs so a powder ring is not left around the bathtub. Added at up to 6%, polysorbate 80 can take the place of witch hazel or oil as the wetting ingredient. Add polysorbate 80 to the liquid stage when making bath bombs.
When using micas with bath bombs it is a must-have ingredient and it will make the color much easier to work with. Micas are oil soluble and polysorbate 80 helps disperse the color in water so the powder color does not cling to the tub.