Sodium Naphthalene Formaldehyde: SNF-20 is a naphthalene based superplasticizer. This product is made by industrial Naphthalene, Beta-sulphonate, Formaldehyde and Alkali via sulphuration, hydrolyzation, condensation and neutralization reactions. It belongs to non-air-entraining superplasticizer. SNF-20 is non-poisonous, odorless, non-flammable and non-corrosive to steel bars.