Artificial naphthol-scarlet is abolishing the culture of the cochineal insect.
"An Introduction to Chemical Science"
R.P. Williams
The mixture is stirred one hour longer at the low temperature and then the nitroso-b-naphthol, which has gradually separated out during the reaction, is filtered with suction and washed thoroughly with water.
"Organic-Syntheses"
Conant, James Bryant
A large vessel is needed for the reaction, as the nitroso-b-naphthol separates in a finely divided condition and there is some tendency to foam.
"Organic-Syntheses"
Conant, James Bryant