1-Hydroxy-4-sulphonatonaphthalene-2-diazonium, sodium salt 1-Naphthalenesulfonic acid, 3-diazo-3,4-dihydro-4-oxo-, sodium salt 17427-62-2 64173-96-2 EINECS 241-453-6 EINECS 264-719-3 Sodium 3-diazo-3,4-dihydro-4-oxonaphthalene-1-sulphonate