Sodium saccharin is also known as saccharin, the scientific name is o-sulfonyl benzene imide sodium salt. White prismatic crystals. Molecular weight 205.17. Melting point 226 ~ 231 ℃. Odorless or slightly fragrant, the taste is very sweet and bitter, it slowly weathers in the air, loses about half of its crystal water and becomes a white powder. The sweetness of the dilute aqueous solution is about 300 to 500 times that of sugar, and the sweetness threshold Chemicalbook value is about 0.00048%. Soluble in water, slightly soluble in ethanol. Its thermal stability in aqueous solution is better than that of saccharin, and there is no change when heated at 100 °C for 2 hours. When the aqueous solution is left for a long time, the sweetness gradually decreases. Mainly used as edible sweetener. It is not decomposed in the human body, and is excreted with urine without nutritional value. It is prepared from phthalic anhydride or toluene as raw materials.