Thiourea dioxide, also known as formamidine sulfinic acid, is a white crystalline powder. Purely crushed thiourea dioxide is a stable compound with neither oxidizing nor reducing properties. The solubility in water is 26.7 g/L (20°C), The pH value of the saturated aqueous melt was 5.0. It is very stable even in an aqueous solution of 20-30 °C, but when the alkaline solution dissolved in thiourea dioxide is heated, it has a high reduction potential (-1230Mv), which will decompose and release the reducing sulfinic acid. , thus reflecting a strong reduction activity.

Thiourea dioxide is a new and environmentally friendly product that replaces hydrosulfite. It has the characteristics of high reduction potential, good thermal stability, non-toxic and tasteless, easy operation, safe storage, convenient transportation, environmental protection and no pollution during use, etc. It has been widely used. It is used in the dyeing of vat dyes and sulfur dyes, the bleaching of wool and silk, the reduction and cleaning of disperse dyes, the stripping of direct or reactive dyes, and the cleaning of dye tanks. In addition, this product is used as reducing agent, bleaching and decolorizing agent, plastic stabilizer, organic synthetic antioxidant, organic synthetic antioxidant and sensitizer for photosensitive materials, etc. ; Catalysts and stabilizers for synthetic resins in the polymer material industry; organic synthetic photosensitive materials, fine chemicals such as pharmaceuticals, pharmaceuticals, fragrances, and the recovery and separation of precious metals have been widely used in industries.