MFR OF DYES AND DIAMINOPHENOL; WOOD PRESERVATIVE; INSECTICIDE; AS INDICATOR; AS REAGENT FOR DETECTION OF POTASSIUM & AMMONIUM IONS. CHEM INT FOR CI SULFUR BLACK 1, CI SULFUR BLACK 2, PHOTOCHEMICALS & EXPLOSIVES; ACID-BASE INDICATOR; FUNGICIDE FOR PROTECTION OF METAL-CUTTING OIL EMULSIONS. POLYMERIZATION INHIBITOR IN STYRENE PRODUCTION. 2,4-Dinitrophenol is used primarily as a chemical intermediate for the production of azo dyes. Use in manufacturing of photographic developers. /SRP: Former use Medication, as dieting aid. Used as a fungicide on railroad ties, wood poles/posts, wood pilings, and in wood pressure treatment to prevent wood rot/decay fungi. Used as an insecticide and miticide for domestic dwellings (outdoor) to control mosquitos.