High-purity thiourea

Thiourea is an organic sulfur-containing compound with the molecular formula CH.₄N₂S, white lustrous crystals, bitter taste, density 1.41 g/cm³, melting point 176–178°C. Used as a raw material in the manufacture of pharmaceuticals, dyes, resins, molding powders, etc., and also as a vulcanization accelerator for rubber and a flotation agent for metal ores. Produced by reacting hydrogen sulfide with lime slurry to form calcium hydrosulfide, which is then reacted with calcium cyanamide. It can also be prepared by melting ammonium thiocyanate or by reacting cyanamide with hydrogen sulfide.

On October 27, 2017, the International Agency for Research on Cancer (IARC) of the World Health Organization published a preliminary compilation of carcinogen lists, in which thiourea was classified as a Group 3 carcinogen.