Sulphur Brown 5

Preparation

(1) 4-(2,4-Dinitrophenylamino)phenol and Sodium hydroxide and water is heated to 105 ℃, then add glucose, Sodium sulfide, sulphur and a small amount of Copper sulfate monohydrate, short time boiling, in 20 hours heating to 260 ~ 270 ℃ and roasting 6 hours; (2) (1) the improvement and Sodium hydroxide solution after boiling, with acid precipitation generated degradation products and filtering, will the paste which add to the above Sodium polysulfide solution. Molten material of save glucose also can get similar dye. Further change the above operation process is to use ?4-(2,4-Dinitrophenylamino)phenol?(by 2-Aminophenol and 1-Chloro-2,4-dinitrobenzene obtained) instead of 4-(2,4-Dinitrophenylamino)phenol.

Properties and Applications

dark brown. Black gray powder. Part of the soluble in water, moderate soluble in sodium sulfide solution, for the red light brown. In concentrated sulfuric acid to dark brown. Dyeing content in alkaline insurance powder solution for yellow brown, oxidation to recover to the original colour and lustre; Sodium hypochlorite solution in almost all fade, join concentrated sulfuric acid color darker.